NEUROPACE INC, 10-K filed on 3/4/2025
Annual Report
v3.25.0.1
Cover - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2024
Feb. 28, 2025
Jun. 30, 2024
Cover [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2024    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity File Number 001-40337    
Entity Registrant Name NEUROPACE, INC.    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 22-3550230    
Entity Address, Address Line One 455 N. Bernardo Avenue    
Entity Address, City or Town Mountain View    
Entity Address, State or Province CA    
Entity Address, Postal Zip Code 94043    
City Area Code 650    
Local Phone Number 237-2700    
Title of 12(b) Security Common Stock, $0.001 par value per share    
Trading Symbol NPCE    
Security Exchange Name NASDAQ    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Non-accelerated Filer    
Entity Small Business true    
Entity Emerging Growth Company true    
Entity Ex Transition Period false    
ICFR Auditor Attestation Flag false    
Document Financial Statement Error Correction [Flag] false    
Entity Shell Company false    
Entity Public Float     $ 135.5
Entity Common Stock, Shares Outstanding   32,560,130  
Documents Incorporated by Reference
Portions of the registrant's definitive proxy statement for the 2025 Annual Meeting of Stockholders, or the Proxy Statement, are incorporated by reference into Part III of this Annual Report on Form 10-K to the extent stated herein. The Proxy Statement will be filed with Securities and Exchange Commission within 120 days of the registrant's fiscal year ended December 31, 2024.
    
Entity Central Index Key 0001528287    
Document Fiscal Year Focus 2024    
Document Fiscal Period Focus FY    
Amendment Flag false    
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Audit Information
 12 Months Ended
Dec. 31, 2024
Audit Information [Abstract]  
Auditor Name PricewaterhouseCoopers
Auditor Location San Jose, California
Auditor Firm ID 238
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Balance Sheets - USD ($)
$ in Thousands
Dec. 31, 2024
Dec. 31, 2023
Current assets    
Cash and cash equivalents $ 13,430 $ 18,058
Short-term investments 39,325 48,396
Accounts receivable 12,851 12,314
Inventory 13,381 11,214
Prepaid expenses and other current assets 2,352 2,737
Total current assets 81,339 92,719
Property and equipment, net 1,052 1,003
Operating lease right-of-use asset 11,843 13,405
Restricted cash 122 122
Deferred offering costs 276 387
Other assets 15 15
Total assets 94,647 107,651
Current liabilities    
Accounts payable 2,954 2,332
Accrued liabilities 9,787 11,180
Operating lease liability 1,860 1,627
Deferred revenue 555 1,090
Total current liabilities 15,156 16,229
Long-term debt 59,525 56,954
Operating lease liability, net of current portion 11,953 13,814
Total liabilities 86,634 86,997
Commitments and contingencies (Note 5)
Stockholders’ equity    
Preferred stock, $0.001 par value, 10,000,000 shares authorized and no shares issued and outstanding as of December 31, 2024 and December 31, 2023 0 0
Common stock, $0.001 par value, 200,000,000 shares authorized as of December 31, 2024 and December 31, 2023; 30,145,039 and 27,823,465 shares issued and outstanding as of December 31, 2024 and December 31, 2023, respectively 30 28
Additional paid-in-capital 538,933 524,435
Accumulated deficit (530,950) (503,809)
Total stockholders’ equity 8,013 20,654
Total liabilities and stockholders’ equity $ 94,647 $ 107,651
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Balance Sheets (Parenthetical) - $ / shares
Dec. 31, 2024
Dec. 31, 2023
Statement of Financial Position [Abstract]    
Preferred stock, par value (in dollars per share) $ 0.001 $ 0.001
Preferred stock shares authorized (in shares) 10,000,000 10,000,000
Preferred stock issued (in shares) 0 0
Preferred stock outstanding (in shares) 0 0
Common stock par value (in dollars per share) $ 0.001 $ 0.001
Common stock shares authorized (in shares) 200,000,000 200,000,000
Common stock issued (in shares) 30,145,039 27,823,465
Common stock outstanding (in shares) 30,145,039 27,823,465
v3.25.0.1
Statements of Operations and Comprehensive Loss - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Income Statement [Abstract]    
Revenue $ 79,906 $ 65,421
Cost of goods sold 20,821 17,299
Gross profit 59,085 48,122
Operating expenses    
Research and development 23,653 20,778
Selling, general and administrative 57,103 54,518
Total operating expenses 80,756 75,296
Loss from operations (21,671) (27,174)
Interest income 3,024 3,050
Interest expense (8,798) (8,517)
Other income (expense), net 304 (315)
Net loss and comprehensive loss $ (27,141) $ (32,956)
Net loss per share attributable to common stockholders, basic (in dollars per share) $ (0.93) $ (1.27)
Net loss per share attributable to common stockholders, diluted (in dollars per share) $ (0.93) $ (1.27)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic (in shares) 29,126,314 25,851,813
Weighted-average shares used in computing net loss per share attributable to common stockholders, diluted (in shares) 29,126,314 25,851,813
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Statements Stockholders’ Equity - USD ($)
$ in Thousands
Total
Common Stock
Additional Paid-In Capital
Accumulated Other Comprehensive Loss
Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2022   25,045,751      
Beginning balance at Dec. 31, 2022 $ 34,777 $ 25 $ 506,713 $ (1,108) $ (470,853)
Increase (Decrease) in Stockholders' Equity [Roll Forward]          
Net loss (32,956)       (32,956)
Unrealized loss adjustment for short-term investment $ 1,108     1,108  
Issuance of common stock pursuant to stock option exercises (in shares) 889,968 889,968      
Issuance of common stock pursuant to stock option exercises $ 149 $ 1 148    
Issuance of common stock pursuant to Employee Stock Purchase Plan (in shares)   280,599      
Issuance of common stock pursuant to Employee Stock Purchase Plan 654   654    
Issuance of common stock as part of At-the-Market offering, net of sales commission and offering expenses (in shares)   933,500      
Issuance of common stock as part of At-the-Market offering, net of sales commission and offering expenses 7,622 $ 1 7,621    
Issuance of common stock upon vesting of restricted stock units (in shares)   728,986      
Issuance of common stock upon vesting of restricted stock units 0 $ 1 (1)    
Shares withheld for taxes (in shares)   (53,999)      
Shares withheld for taxes (259)   (259)    
Repurchase of common stock (in shares)   (1,340)      
Change in early exercise liability 1   1    
Stock-based compensation $ 9,558   9,558    
Ending balance (in shares) at Dec. 31, 2023 27,823,465 27,823,465      
Ending balance at Dec. 31, 2023 $ 20,654 $ 28 524,435 0 (503,809)
Increase (Decrease) in Stockholders' Equity [Roll Forward]          
Net loss $ (27,141)       (27,141)
Issuance of common stock pursuant to stock option exercises (in shares) 556,718 556,718      
Issuance of common stock pursuant to stock option exercises $ 810 $ 1 809    
Issuance of common stock pursuant to Employee Stock Purchase Plan (in shares)   202,616      
Issuance of common stock pursuant to Employee Stock Purchase Plan 1,121   1,121    
Issuance of common stock as part of At-the-Market offering, net of sales commission and offering expenses (in shares)   444,555      
Issuance of common stock as part of At-the-Market offering, net of sales commission and offering expenses 3,167   3,167    
Issuance of common stock upon vesting of restricted stock units (in shares)   1,184,284      
Issuance of common stock upon vesting of restricted stock units 0 $ 1 (1)    
Shares withheld for taxes (in shares)   (65,317)      
Shares withheld for taxes (881)   (881)    
Repurchase of common stock (in shares)   (1,282)      
Change in early exercise liability 1   1    
Stock-based compensation $ 10,282   10,282    
Ending balance (in shares) at Dec. 31, 2024 30,145,039 30,145,039      
Ending balance at Dec. 31, 2024 $ 8,013 $ 30 $ 538,933 $ 0 $ (530,950)
v3.25.0.1
Statements of Stockholders’ Equity (Parenthetical) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Statement of Stockholders' Equity [Abstract]    
Issuance costs $ 212 $ 509
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Statements of Cash Flows - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Cash flows from operating activities    
Net loss $ (27,141) $ (32,956)
Adjustments to reconcile net loss to net cash used in operating activities    
Stock-based compensation expense 10,282 9,558
Depreciation 207 172
Amortization of debt discount and issuance costs 228 283
Non-cash interest expense 954 1,075
PIK interest incurred but not paid on term loan 1,389 2,683
Amortization of right-of-use asset 1,562 1,433
(Gain) loss on short-term investments (229) 315
Inventory write-downs 251 196
Other 1 24
Changes in operating assets and liabilities    
Accounts receivable (537) (4,850)
Inventory (2,418) (1,698)
Prepaid expenses and other assets 384 381
Accounts payable 671 240
Accrued liabilities (1,392) 3,768
Deferred revenue (534) 1,090
Operating lease liabilities (1,627) (1,415)
Net cash used in operating activities (17,949) (19,701)
Cash flows from investing activities    
Acquisition of property and equipment (306) (173)
Proceeds from sale of short-term investments 9,300 23,200
Net cash provided by investing activities 8,994 23,027
Cash flows from financing activities    
Proceeds from issuance of common stock under employee plans 1,931 803
Taxes withheld and paid related to net share settlement of equity awards (881) (259)
Proceeds from At-the-Market offering, net of sales commission 3,277 7,888
Payment of deferred offering costs 0 (305)
Net cash provided by financing activities 4,327 8,127
Net (decrease) increase in cash and cash equivalents (4,628) 11,453
Cash, cash equivalents and restricted cash    
Beginning of year 18,180 6,727
End of year 13,552 18,180
Reconciliation of cash, cash equivalents and restricted cash to balance sheets:    
Cash and cash equivalents 13,430 18,058
Restricted cash 122 122
Total cash, cash equivalents and restricted cash 13,552 18,180
Supplemental disclosure of cash flow information:    
Cash paid for interest 6,226 4,476
Supplemental disclosures of non-cash investing and financing information:    
Net change in accrued liabilities from early exercise of options (1) (1)
Purchase of property and equipment included in accounts payable 19 69
Deferred offering costs offset against additional paid-in capital $ 110 $ 265
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The Company
 12 Months Ended
Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
The Company The Company
NeuroPace, Inc., or the Company, was incorporated in the state of Delaware on November 19, 1997. The Company is a medical device company that has developed the RNS System, the only commercially available brain-responsive neuromodulation system designed for treating drug-resistant focal epilepsy by delivering personalized, real-time treatment at the seizure source. The Company began commercializing its products in the United States in 2014.
At-the-Market Equity Offering
In November 2022, the Company filed a Registration Statement on Form S-3, or Shelf, with the Securities and Exchange Commission, or the SEC, in relation to the registration of common stock, preferred stock, debt securities, warrants or any combination thereof for up to an aggregate of $150.0 million, of which $50.0 million may be issued and sold pursuant to an at-the-market, or ATM, offering program for sales of the Company’s common stock under a sales agreement, or Sales Agreement, with Leerink Partners LLC, or Leerink (formerly SVB Securities LLC). The Company agreed to pay Leerink up to 3.0% of the gross proceeds of sales of common stock made through the Sales Agreement. The Company’s common stock would be sold at prevailing market prices at the time of the sale and, as a result, prices may vary. During the year ended December 31, 2023, the Company sold 933,500 shares of common stock under the Sales Agreement for gross proceeds of $8.1 million, or $7.6 million after deducting sales commissions and offering expenses. During the year ended December 31, 2024, the Company sold 444,555 shares of common stock under the Sales Agreement for gross proceeds of $3.4 million, or $3.2 million after deducting sales commissions and offering expenses. As of December 31, 2024, the Company has $38.5 million remaining under its ATM program. Refer to Note 12 for information on the termination of the ATM program in February 2025.
Liquidity and Capital Resources
The Company has incurred operating losses and negative cash flows from operations since its inception and has an accumulated deficit of $531.0 million as of December 31, 2024. For the years ended December 31, 2024 and 2023, the Company used $17.9 million and $19.7 million, respectively, of cash in its operating activities. As of December 31, 2024, the Company had cash, cash equivalents and short-term investments of $52.8 million. Historically, the Company has funded its operations principally through the sales of its products, issuance of equity securities and debt financing.
The Company’s financial statements have been prepared on the basis of the Company continuing as a going concern for the next 12 months. Management believes that the Company’s cash, cash equivalents and short-term investments will allow the Company to continue its planned operations for at least the next 12 months from the date of the issuance of these financial statements.
In connection with the Term Loan described in Note 6, the Company will need to be in compliance with a minimum annual net revenue covenant determined in accordance with generally accepted accounting principles of $70.0 million in each of the years ending December 31, 2024 and December 31, 2025 and maintain a minimum cash and cash equivalents balance of $5.0 million. If the Company cannot generate sufficient revenue in the future, the Company may not be in compliance with the annual net revenue covenant and the lender may call the debt resulting in the Company immediately needing additional capital, and resulting in a going concern. The Company’s ability to raise additional capital may be adversely impacted by global economic conditions and disruptions to, and volatility in, the financial markets in the United States and worldwide. If the Company is unable to raise capital when needed, it will need to delay, limit, reduce or terminate planned commercialization or product development activities in order to reduce costs. As of December 31, 2024, the Company was in compliance with all covenants of the Term Loan.
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Summary of Significant Accounting Policies
 12 Months Ended
Dec. 31, 2024
Accounting Policies [Abstract]  
Summary of Significant Accounting Policies Summary of Significant Accounting Policies
Basis of Presentation
The financial statements have been prepared in conformity with generally accepted accounting principles in the United States, or GAAP, as defined by the Financial Accounting Standards Board, or the FASB.
Use of Estimates
The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the amounts and disclosures reported in the financial statements. The Company uses significant judgment when making estimates related to the provision for excess and obsolete inventories. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may ultimately materially differ from these estimates and assumptions.
Revenue Recognition
The Company derives most of its revenue from sales of RNS Systems to hospital facilities (typically comprehensive epilepsy centers, or Level 4 CECs) that implant its products. Beginning in the fourth quarter of 2022, the Company also derives revenue from sales of DIXI Medical products, primarily to its current customer base. Beginning in the fourth quarter of 2023, the Company also derives revenue from services provided to Rapport Therapeutics, Inc., or Rapport.
The Company recognizes revenue in accordance with ASC 606, Revenue from Contracts with Customers. Under ASC 606, revenue is recognized when a customer obtains control of promised goods or services, in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the Company performs the following five steps:
i.identify the contract(s) with a customer;
ii.identify the performance obligations in the contract;
iii.determine the transaction price;
iv.allocate the transaction price to the performance obligations in the contract; and
v.recognize revenue when (or as) the entity satisfies a performance obligation.
At contract inception, the Company assesses the products or services promised within each contract and determines those that are performance obligations. The Company’s contracts with customers for the RNS System often include a promise to transfer products, as well as an implied promise to provide a service to the customer, which is access to the Company’s Patient Data Management System, or PDMS, and nSight Platform. The Company has concluded that the RNS System and its related products represent a single performance obligation, as the customer cannot benefit from the products individually, and that access to the PDMS and nSight Platform represent separate performance obligations, as the clinicians can utilize them with other components of the RNS System that are readily available.
The Company determines the transaction price based on the amount it expects to be entitled to in exchange for transferring the promised product or service to the customer, which is based on the invoiced price for the products or services. All prices are at fixed amounts per the sales agreement with the customer and there are no discounts, rebates or other price concessions.
When a contract contains multiple performance obligations, the Company allocates the transaction price to each performance obligation based on its relative standalone selling price. Standalone selling prices are based on observable prices at which the Company separately sells its products or services. If a standalone selling price is not directly observable, the Company estimates the standalone selling price considering market data, cost, gross margin, and other available information.
The Company typically delivers its RNS System and related products to a hospital on the date of the scheduled procedure. There is no commitment or contract until the delivery of the product and the procedure may be canceled
at any time. Once the device has been implanted in or otherwise provided to a patient, the customer is considered to have accepted the delivery (i.e., has approved the contract) and both parties are committed to perform their respective obligations. Assuming all other revenue recognition criteria are met, the Company recognizes revenue from the sale of its RNS System and related products at a point in time when the procedure is completed and the device is implanted in a patient.
The Company also ships the RNS System and related products to customers who place orders ahead of scheduled procedures. Such orders or contracts generally include a promise to transfer products only. As such, the Company recognizes revenue from these orders or contracts at a point in time when the customer obtains control of the products.
The Company recognizes service revenue related to the PDMS and the nSight Platform on a ratable basis over the period in which the Company expects to provide access to clinicians. The Company has concluded that such service revenue is immaterial.
The Company’s contracts with customers for DIXI Medical products generally include a promise to transfer products only. As such, the Company recognizes revenue from the sale of DIXI Medical products at a point in time when the customer obtains control of the products.
The Company recognizes revenue under its contract with Rapport to provide biomarker monitoring and data analysis services. Revenue from biomarker monitoring is recognized ratably over the two-year contractual support period, as the benefits provided by the Company’s performance are simultaneously consumed by the customer. Revenue related to data analysis is recognized upon completion of the services. The Company’s contract with Rapport commenced during the fourth quarter of 2023. The related revenue recognized for the years ended December 31, 2024 and 2023 were $1.2 million and $0.4 million, respectively.
The Company recognizes revenue for arrangements where it has satisfied its performance obligations but has not issued invoices. These amounts are recorded as unbilled receivables, which are included in accounts receivable on the balance sheet, as the Company has an unconditional right to payment at the end of the applicable period.
Payment terms are typically 30 days from the fulfillment of the orders and fall within the one-year guidance for the practical expedient which allows the Company to forgo adjustment of the promised amount of consideration for the effects of a significant financing component. Sales taxes that are collected from customers and remitted to governmental authorities are accounted for on a net basis and therefore are excluded from net sales, however, most of the Company’s sales are tax exempt. The Company believes that collection is probable as it has no history of uncollectible accounts and the customers are large, creditworthy institutions.
As allowed under the practical expedient, the Company does not disclose the value of unsatisfied performance obligations for contracts with an original expected length of one year or less. Costs associated with product sales include commissions, where the Company applies the practical expedient and recognizes commissions as expense when incurred because the expense is incurred over a period of time of less than one year. Commissions are reported in selling, general and administrative expense in the statements of operations and comprehensive loss.
The Company’s contract balances were accounts receivable of $12.9 million and $12.3 million as of December 31, 2024, and December 31, 2023, respectively.
The Company’s contract liabilities consist of deferred revenue of $0.6 million and $1.1 million as of December 31, 2024 and 2023, respectively. The Company’s deferred revenue balance was $0.6 million as of December 31, 2024, which is expected to be recognized as revenue in 2025. Revenue recognized during the year ended December 31, 2024 that was included in the deferred revenue balance at the beginning of the year was $1.1 million.
As of December 31, 2024, the aggregate amount of the transaction price allocated to the remaining performance obligations that are unsatisfied or partially unsatisfied was $1.7 million, which the Company expects to recognize as revenue by December 2025.
Fair Value of Financial Instruments
Carrying amounts of certain of the Company’s financial instruments, including cash equivalents, accounts receivable, accounts payable and accrued liabilities, approximate fair value because of the short-term nature of these instruments. The Company has a short-term investment in a fixed income mutual fund, which is classified as equity security and carried at fair value based on quoted market prices. Changes in the fair value of the short-term investment are recorded in income or loss. The Company believes that its borrowings bear interest at the prevailing market rates for instruments with similar characteristics; accordingly, the carrying value of this instrument approximates its fair value. The Company determines the fair value of financial and non-financial assets and liabilities using the fair value hierarchy which establishes three levels of inputs that may be used to measure fair value (see Note 3).
Cash and Cash Equivalents
The Company considers all highly liquid investments with original maturities of three months or less at the time of purchase to be cash equivalents. Cash equivalents that are available-for-sale investments are recorded at fair value, based on quoted market prices. As of December 31, 2024 and December 31, 2023, the Company’s cash equivalents are entirely comprised of investments in money market funds.
Restricted Cash
Restricted cash is comprised of cash that is restricted as to withdrawal or use under the terms of certain contractual agreements. Restricted cash for the years ended December 31, 2024 and December 31, 2023 consists of collateral for the amended letter of credit that was issued in connection with the Company’s facility lease (see Note 5).
Concentration of Credit Risk, and Other Risks and Uncertainties
Financial instruments that potentially subject the Company to credit risk consist of cash and cash equivalents, short-term investments and accounts receivable to the extent of the amounts recorded on the balance sheets. The Company’s cash is invested in major financial institutions in the United States. Deposits in these financial institutions may exceed federally insured limits, and the Company is exposed to credit risk on deposits in the event of default of the financial institutions to the extent account balances exceed the amount insured by the Federal Deposit Insurance Corporation. The Company’s cash equivalents are invested in money market funds.
The Company’s accounts receivable, with the exception of $0.1 million, are due from a variety of health care organizations in the United States. For the years ended December 31, 2024 and December 31, 2023, there were no customers that represented 10% or more of revenue. As of December 31, 2024 and December 31, 2023, no customer represented 10% or more of the Company’s accounts receivable.
Accounts Receivable
Accounts receivable are recorded at the invoiced amount and do not bear interest. The Company makes estimates on the collectability of customer accounts based primarily on analysis of historical trends and experience, the age of the receivable and changes in customers’ financial condition. The Company uses its judgment, based on the best available facts and circumstances, and records an allowance against amounts due to reduce the receivable to the amount that is expected to be collected. The Company determined that no allowance was required as of December 31, 2024 and December 31, 2023. To date, the Company has not experienced any material credit-related losses.
Inventories
Inventories are valued at the lower of cost or net realizable value. Cost is determined using the first-in, first-out method for all inventories. Net realizable value is determined as the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal and transportation. The Company regularly reviews inventory quantities in consideration of actual loss experiences, projected future demand, and remaining shelf life to record a provision for excess and obsolete inventory when appropriate. The Company’s policy is to
write down inventory that has become obsolete, inventory that has a cost basis in excess of its expected lower of cost or net realizable value, and inventory in excess of expected requirements. The estimate of excess quantities is judgmental and primarily dependent on the Company’s estimates of future demand for a particular product. If the estimate of future demand is too high, the Company may have to increase the reserve for excess inventory for that product and record a charge to the cost of goods sold. Inventory write-downs were $0.3 million and $0.2 million for the years ended December 31, 2024 and December 31, 2023, respectively.
Property and Equipment, net
Property and equipment, net is stated at cost less accumulated depreciation. Depreciation is calculated using the straight-line method over the estimated useful lives of the assets, generally three to five years. Leasehold improvements are amortized using the straight-line method over the shorter of the assets’ estimated useful lives or the remaining term of the lease. When assets are retired or otherwise disposed of, the cost and accumulated depreciation are removed from the balance sheet, and any resulting gain or loss is reflected in operations in the period realized. Maintenance and repairs are charged to operations as incurred.
Impairment of Long-Lived Assets
The Company reviews long-lived assets, including property and equipment, for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If indicators of impairment exist, an impairment loss would be recognized when estimated undiscounted future cash flows expected to result from the use of the assets and their eventual disposition are less than their carrying amount. Impairment, if any, is measured as the amount by which the carrying amount of the long-lived assets exceeds their fair value. The Company did not record any impairment of long-lived assets for the years ended December 31, 2024 and December 31, 2023.
Leases
The Company determines if an arrangement is a lease, or contains a lease, at inception. Operating leases are included in operating lease right-of-use, or ROU, assets, operating lease liability, and operating lease liability, net of current portion on the Company’s balance sheets.
ROU assets and lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. Since the Company’s lease does not provide an implicit rate, the Company uses its incremental borrowing rate based on the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term and in a similar economic environment at commencement date in determining the present value of future payments. The ROU asset also includes any lease payments made to the lessor at or before the commencement date, minus lease incentives received, and initial direct costs incurred. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. The Company elected certain practical expedients under ASC 842, Leases, including the package of practical expedients, which among other things, allowed the Company to carry forward prior conclusions about lease identification and classification, as well as elections to not record leases with an initial term of twelve months or less on the balance sheet, and to combine the lease and non-lease components in determining the lease liabilities and ROU assets.
Deferred Offering Costs
The Company capitalizes, within other assets, certain legal, accounting and other third-party fees that are directly related to the Company’s in-process equity financings, including its ATM offering, until such financings are consummated. After consummation of the equity financing, these costs are recorded as a reduction of the proceeds received as a result of the offering. Should a planned equity financing be abandoned, terminated or significantly delayed, the deferred offering costs are immediately written off to operating expenses. Upon issuing shares under the ATM offering during the years ended December 31, 2024 and 2023, $0.1 million and $0.3 million, respectively, of deferred offering costs were recorded against the proceeds from the ATM offering and recorded in stockholders
equity as a reduction of additional paid-in capital. As of December 31, 2024 and 2023, $0.3 million and $0.4 million of deferred offering costs related to the ATM offering were recorded on the balance sheets, respectively.
Government Programs
In May 2021, the Company was awarded a grant by the National Institutes of Health, or NIH, to support research of thalamocortical responsive neurostimulation for the treatment of Lennox-Gastaut Syndrome, a type of epilepsy. The award was issued for a five-year period and has a total budget of over $9.3 million, which includes approximately $5.5 million in funding for subawards to third-party academic epilepsy centers that are collaborating on the study and are subinvestigators on the study funded by NIH. The subawardees are determined by NIH. The Company’s responsibility for the subawards is to submit the funding requests on behalf of the subawardees. The funding of subawards does not have any impact on the Company’s financial statements. Initially funding was approved for the first year beginning June 1, 2021 and provides for reimbursement of qualified direct and indirect expenses in the amount of $0.8 million, including $0.4 million for subawards. Approvals of funds for years two through five are subject to the completion of certain milestones. On July 30, 2022, the Company received funding approval for year two in the amount of $2.6 million, which includes $1.6 million for subawards. On May 25, 2023, the Company received funding approval for year three in the amount of $3.0 million, which includes $1.5 million for subawards. On July 22, 2024, the Company received funding approval for year four in the amount of $1.7 million, which includes $1.0 million for subawards.
For funds received under the NIH funding agreement, the Company recognizes a reduction in research and development expenses in an amount equal to the qualifying expenses incurred in each period up to the amount awarded by the NIH. The Company received $1.7 million and $1.4 million in funding during the years ended December 31, 2024 and 2023, respectively. Through December 31, 2024, $3.8 million of qualifying expenses have been incurred and funded by the NIH related to the first to fourth year of funding.
Qualifying expenses incurred by the Company in advance of funding by the NIH are recorded within prepaid expenses and other current assets on the balance sheets. As of December 31, 2024, the Company recorded prepaid expenses and other current assets of less than $0.1 million related to the fourth year of funding.
Warranty
Warranty costs are accrued based on the Company’s best estimates when management determines that it is probable a charge or liability has been incurred and the amount of loss can be reasonably estimated. While the Company believes that historical experience provides a reliable basis for estimating such warranty cost, unforeseen quality issues or component failure rates could result in future costs in excess of such estimates. The warranty liability as of December 31, 2024 and December 31, 2023 was immaterial.
Cost of Goods Sold
The Company manufactures its products at its facility. Cost of goods sold consists primarily of costs related to materials, components and subassemblies, manufacturing overhead, direct labor, and reserves for excess and obsolete inventories. A significant portion of the Company’s cost of goods sold currently consists of manufacturing overhead costs. These overhead costs include the cost of facilities, material procurement, inventory control, quality assurance, equipment and operating supervision and management. Cost of goods sold also includes depreciation expense for production equipment and certain direct costs such as shipping costs. Shipping and handling costs are considered a fulfillment activity and are included in cost of goods sold as incurred.
Research and Development Expenditures
The Company expenses research and development costs as incurred. Research and development expenses consist primarily of engineering, product development, clinical studies to develop and support the Company’s products, regulatory expenses, medical affairs and other costs associated with products and technologies that are in development, including quality assurance. Research and development expenses include employee compensation, including stock-based compensation, supplies, consulting, prototyping, testing, materials, travel expenses, depreciation and an allocation of facility overhead expenses. Additionally, research and development expenses
include costs associated with clinical studies including clinical trial design, clinical site reimbursement, data management, travel expenses, the cost of products used for clinical trials and costs associated with regulatory compliance and submitting and maintaining regulatory filings.
Advertising Costs
The Company expenses advertising costs as incurred. Advertising costs include design and production costs, including website development, physician and patient testimonial videos, written media campaigns, and other items. Advertising costs of $0.7 million and $0.7 million were expensed during the years ended December 31, 2024 and December 31, 2023, respectively.
Stock-Based Compensation
The Company accounts for stock-based employee compensation in accordance with ASC 718, Stock Compensation. ASC 718 requires the measurement of compensation based on the grant date fair value of the stock option or restricted stock unit (see Note 8). The Company amortizes the fair value of each award on a straight-line basis over the requisite service period of the award.
Income Taxes
The Company accounts for income taxes under the asset and liability method. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to affect taxable income. Valuation allowances are established when necessary to reduce deferred tax assets to the amounts expected to be realized.
The Company assesses all material positions taken in any income tax return, including all significant uncertain positions, in all tax years that are still subject to assessment or challenge by relevant taxing authorities. Assessing an uncertain tax position begins with the initial determination of the position’s sustainability and is measured at the largest amount of benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement. As of each balance sheet date, unresolved uncertain tax positions must be reassessed, and the Company will determine whether (i) the factors underlying the sustainability assertion have changed and (ii) the amount of the recognized tax benefit is still appropriate. The recognition and measurement of tax benefits requires significant judgment. Judgments concerning the recognition and measurement of a tax benefit might change as new information becomes available.
Net Loss per Share Attributable to Common Stockholders
Basic net loss per common share is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period, without consideration of potentially dilutive securities. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. For purposes of the diluted net loss per share calculation, stock options, common stock subject to repurchase related to early exercise of stock options, and restricted stock units are considered to be potentially dilutive securities. Basic and diluted net loss attributable to common stockholders per share is presented in conformity with the two-class method required for participating securities. The Company considers the shares issued upon the early exercise of stock options subject to repurchase to be participating securities, because holders of such shares have non-forfeitable dividend rights in the event a dividend is paid on common stock. The holders of the shares issued upon early exercise of stock options subject to repurchase do not have a contractual obligation to share in the Company’s losses. As such, the net loss was attributed entirely to common stockholders. Because the Company has reported a net loss for all periods presented, diluted net loss per common share is the same as basic net loss per common share for those periods.
JOBS Act Accounting Election
The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012, or the JOBS Act. Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date the Company (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these financial statements may not be comparable to companies that comply with new or revised accounting pronouncements as of public company effective dates.
Recent Accounting Pronouncements
Recently Adopted Accounting Pronouncements
In accordance with Accounting Standards Codification, or ASC, 280, Segment Reporting, the Company operates as one operating and reportable segment. In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The amended guidance requires all public entities, including public entities with a single reportable segment, to disclose in interim and annual periods significant segment expenses that are regularly provided to the chief operating decision maker, or CODM, to allocate resources and assess performance, as well as the aggregate amount of other segment items included in the reported measure of segment profit or loss. The Company adopted this ASU effective for the fiscal year ended December 31, 2024 on a retrospective basis. Refer to Note 11 for further information on the Company’s reportable segment.
Recent Accounting Pronouncements Not Yet Adopted
In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures. This ASU requires greater disaggregation of information about a reporting entity's effective tax rate reconciliation as well as information on income taxes paid. This ASU applies to all entities subject to income taxes and is intended to help investors better understand an entity’s exposure to potential changes in jurisdictional tax legislation and assess income tax information that affects cash flow forecasts and capital allocation decisions. This ASU is effective for annual periods beginning after December 15, 2024, with early adoption permitted, and should be applied on a prospective basis although retrospective application is permitted. The Company is currently evaluating the impact this standard will have on its financial statement disclosures.
In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40). This ASU is intended to provide more detailed information about specified categories of expenses (including employee compensation, depreciation, and amortization) included in certain expense captions presented on the face of the income statement. This ASU is effective for fiscal years beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. This ASU may be applied either prospectively to financial statements issued for reporting periods after its effective date or retrospectively to all prior periods presented in the financial statements. The Company is currently assessing the impact this standard will have on its financial statement disclosures.
v3.25.0.1
Fair Value Measurements
 12 Months Ended
Dec. 31, 2024
Fair Value Disclosures [Abstract]  
Fair Value Measurements Fair Value Measurements
The Company measures certain financial assets and liabilities at fair value on a recurring basis. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. A three-tier fair value hierarchy is established as a basis for considering such assumptions and for inputs used in the valuation methodologies in measuring fair value:
Level 1Quoted prices in active markets for identical assets or liabilities.
Level 2Observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.
Level 3Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.
The Company utilizes the market approach to measure fair value for its financial assets and liabilities. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets or liabilities.
The following table summarizes the Company’s financial assets (cash equivalents and marketable securities) at fair value as of December 31, 2024 (in thousands):
Fair Value as of December 31, 2024
Basis for Fair Value Measurements
(Level 1)(Level 2) (Level 3)
Assets:
Money market funds, included in cash and cash equivalents$13,349 $13,349 $— $— 
Fixed income mutual funds, included in short-term investments39,325 39,325 — — 
Total$52,674 $52,674 $— $— 
The following table summarizes the Company’s financial assets (cash equivalents and marketable securities) at fair value as of December 31, 2023 (in thousands):
Fair Value as of December 31, 2023
Basis for Fair Value Measurements
(Level 1)(Level 2) (Level 3)
Assets:
Money market funds, included in cash and cash equivalents$16,125 $16,125 $— $— 
Fixed income mutual funds, included in short-term investments48,396 48,396 — — 
Total$64,521 $64,521 $— $— 
There were no liabilities measured at fair value on a recurring and non-recurring basis as of December 31, 2024 and December 31, 2023.
The money market funds are highly liquid and primarily invest in short-term fixed income securities issued by the U.S. government and U.S. government agencies.
The Company’s available-for-sale investment comprises a short-term investment in a fixed income mutual fund, which primarily invests in debt securities issued by the U.S. government and U.S. government agencies and corporate bonds and notes. Interest income from short-term investment is recorded in interest income. During the years ended December 31, 2024 and 2023, the Company recognized $0.2 million and $1.0 million in unrealized gains from its short-term investment, respectively. As of December 31, 2024, the Company’s short-term investment had a cumulative unrealized net gain of $0.1 million. As of December 31, 2023, the Company’s short-term investment had a cumulative unrealized net loss of $0.1 million, which included an adjustment of $1.1 million unrealized loss recorded in other income (expense), net in the year ended December 31, 2023. The adjustment was not material to any previously issued financial statements.
v3.25.0.1
Balance Sheet Components
 12 Months Ended
Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Balance Sheet Components Balance Sheet Components
Inventory
Inventories consist of the following (in thousands):
December 31,
2024
2023
Raw materials$4,248 $4,090 
Work-in-process1,778 627 
Finished goods7,355 6,497 
Total$13,381 $11,214 
Property and Equipment, net
Property and equipment, net consists of the following (in thousands):
December 31,
2024
2023
Machinery, equipment, furniture and fixtures$4,659 $4,522 
Computer equipment and software1,932 1,822 
Leasehold improvements2,435 2,426 
9,026 8,770 
Less: Accumulated depreciation(7,974)(7,767)
Property and equipment, net $1,052 $1,003 

Depreciation expense for the years ended December 31, 2024 and December 31, 2023 was $0.2 million and $0.2 million, respectively.
Accrued Liabilities
Accrued liabilities consist of the following (in thousands):
December 31,
2024
2023
Payroll and related expenses $8,178 $9,655 
Inventory purchases575 588 
Professional fees50 30 
Other984 907 
$9,787 $11,180 
v3.25.0.1
Commitments and Contingencies
 12 Months Ended
Dec. 31, 2024
Commitments and Contingencies Disclosure [Abstract]  
Commitments and Contingencies Commitments and Contingencies
Facility Lease
In August 2011, the Company entered into a non-cancelable operating lease for combined office and manufacturing facilities in Mountain View, California. The lease was scheduled to expire in April 2019 and was amended in May 2018 to extend it through June 2024. In August 2022, the Company amended the lease to extend it through June 2030. The second amendment contained a rent-free period from September 2022 through December 2022. The Company has an option to extend the lease for a period of five years, commencing on July 1, 2030 and expiring on June 30, 2035. In conjunction with the original lease agreement, the Company obtained a letter of credit for $0.9 million in lieu of a security deposit. In May 2019, the letter of credit was amended and reduced to $0.7 million. In June 2021, the letter of credit was amended and further reduced to $0.2 million.
The terms of the facility lease provide for rental payments on a graduated scale; however, rent expense is recognized on a straight-line basis over the lease term. Rental payments range from $2.8 million to $3.3 million per year over the extended term of the lease.
The maturities of operating lease liabilities as of December 31, 2024 are as follows (in thousands):
2025$2,942 
20263,031 
20273,122 
20283,215 
20293,312 
Thereafter1,704 
Total undiscounted lease payments17,326 
Less: imputed interest3,513 
Total operating lease liability13,813 
Less: current portion1,860 
Operating lease liability, net of current portion$11,953 
Operating lease cost was $2.8 million and $2.8 million for the years ended December 31, 2024 and 2023, respectively. As of December 31, 2024, the remaining term for the operating lease in Mountain View, California was 5.5 years, and the discount rate used to measure the lease liability for such operating lease upon recognition was 8.5%.
During the years ended December 31, 2024 and 2023, cash paid for amounts included in operating lease liabilities of $2.9 million and $2.8 million, respectively, was included in cash flows from operating activities on the statements of cash flows.
Distribution Agreement
In August 2022, the Company entered into an exclusive distribution agreement, or the Distribution Agreement, with DIXI Medical USA Corp, or DIXI Medical, pursuant to which the Company became the exclusive U.S. distributor of DIXI Medical’s stereo electroencephalography product line. The Distribution Agreement has an initial term of three years, which expires September 30, 2025. The Distribution Agreement automatically renews for additional one-year terms, unless either party provides written notice to the other party of its intention to not renew at least 180 days prior to the expiration of the then-current term. The current Distribution Agreement will automatically renew unless either party provides notice of intent not to renew by April 3, 2025.
To maintain the distribution rights, the Company is required to purchase a minimum of $2.4 million of DIXI Medical’s products during the twelve months beginning October 2022, and to increase the minimum purchase by 10% for each of the two subsequent years. The Company met the purchase commitment for the first two years and expects to meet the purchase commitment for the third year, which is through September 2025.
Indemnifications
In the normal course of business, the Company enters into contracts and agreements that contain a variety of representations and warranties and may provide for indemnification of the counterparty. The Company’s exposure under these agreements is unknown because it involves claims that may be made against it in the future but have not yet been made. The Company may, from time to time, be subject to claims or be required to defend actions related to its indemnification obligations.
The Company indemnifies each of its directors and officers for certain events or occurrences, subject to certain limits, while the director or officer is or was serving at the Company’s request in such capacity, as permitted under Delaware law and in accordance with its certificate of incorporation and bylaws. The term of the indemnification period lasts as long as the director or officer may be subject to any proceeding arising out of acts or omissions of
such individual in such capacity. The maximum amount of potential future indemnification is unlimited. The Company believes that the fair value of these indemnification obligations is minimal. Accordingly, the Company has not recognized any liabilities relating to these obligations as of December 31, 2024 and December 31, 2023.
Contingencies
From time to time, the Company may have certain contingent liabilities that arise in the ordinary course of business activities. The Company accrues a liability for such matters when it is probable that future expenditures will be made and such expenditures can be reasonably estimated. The Company determined that no accrual related to contingencies was required as of December 31, 2024 and December 31, 2023.
Legal Proceedings
The Company is not involved in any pending legal proceedings that it believes could have a material adverse effect on its business, results of operations, financial condition, or cash flows. From time to time, the Company may pursue litigation to assert its legal rights and such litigation may be costly and divert the efforts and attention of its management and technical personnel which could adversely affect its business. The Company regularly evaluates current information to determine whether any accruals should be adjusted and whether new accruals are required. Such accruals, if any, reflect the estimable and probable costs that the Company may incur from the outcomes of its legal proceedings. Legal costs are expensed as incurred. There were no contingent liabilities requiring accrual as of December 31, 2024 and 2023.
v3.25.0.1
Debt
 12 Months Ended
Dec. 31, 2024
Debt Disclosure [Abstract]  
Debt Debt
Term Loan
In September 2020, the Company entered into a Term Loan Agreement with CRG Partners IV L.P. and its affiliates for total borrowings of up to $60.0 million, or the Term Loan, and borrowed $50.0 million. The remaining $10.0 million of the Term Loan was available to the Company for borrowing until March 31, 2022 if the Company achieved a revenue-based milestone in 2021. The revenue-based milestone was not achieved, and the remaining $10.0 million of the Term Loan expired without being drawn.
The Term Loan initially bore interest at a rate of 12.5% per year. In February 2023, the Term Loan was amended which increased the annual interest rate from 12.5% to 13.5% effective March 1, 2023. The amendment was accounted for as a debt modification in accordance with ASC 470, Debt and the Term Loan’s effective interest rate increased from 15.7% to 16.8%. Payments under the Term Loan are made quarterly with payment dates fixed at the end of each calendar quarter. Through December 2020, the Company had the option to pay the entire interest paid-in-kind, or PIK, by increasing the principal of the Term Loan. From January 2021 through December 2022, the Company had the option to pay interest as follows: 7.5% per annum paid in cash and 5.0% per annum PIK by increasing the principal of the Term Loan. From January 2023 through June 2025, the Company had the option to pay interest as follows: 8.5% per annum paid in cash and 5.0% per annum PIK by increasing the principal of the Term Loan. For each payment date from April 2022 through June 2024, the Company elected the PIK option, increasing the principal of the Term Loan by $6.0 million.
The Term Loan was interest-only through September 2023, which could be extended through September 2025 at the Company’s option if the Company completed its initial public offering, or IPO, on or prior to September 30, 2023. In connection with closing the IPO in April 2021, the Company extended the interest-only period to September 30, 2025. Following the interest-only period, principal payment was to be due in one installment on September 30, 2025. In May 2024, the Term Loan was amended to extend the final maturity by one year to September 30, 2026 and eliminate the PIK interest option after June 30, 2024. The amendment was accounted for as a troubled debt restructuring in accordance with ASC 470 and no gain or loss was recognized. The Term Loan includes a fee upon repayment of the loan equal to 10% of the aggregate principal amount being prepaid or repaid, or the backend fee. As of December 31, 2024, the Term Loan had an annual effective interest rate of 15.5% per year.
The Term Loan is collateralized by substantially all of the Company’s assets. The Term Loan Agreement contains customary representations and warranties, covenants, events of default and termination provisions. The
financial covenants require that the Company achieve minimum annual revenue thresholds commencing in 2021 and maintain a minimum balance of cash and cash equivalents (see Note 1). In February 2023, the Term Loan was amended to reduce the minimum annual net revenue covenant to $45.0 million for the year ended December 31, 2023.
The Company paid $1.0 million in fees to the lender and third parties which is reflected as a discount on the loan and is being accreted over the life of the loan using the effective interest method. Also, the Company issued warrants to the lender for a total of 346,823 shares of Series B’ redeemable convertible preferred stock. The warrants had a fair value of $0.6 million as of the issuance date, which was accounted for as debt issuance costs.
During the years ended December 31, 2024 and December 31, 2023, the Company recorded interest expense related to debt discount and debt issuance costs of the Term Loan of $0.2 million and $0.3 million, respectively.
Interest expense on the Term Loan was $8.8 million and $8.5 million during the years ended December 31, 2024 and December 31, 2023, respectively.
As of December 31, 2024, future minimum payments for the Term Loan are as follows (in thousands):
Term Loan
2025
$7,666 
2026
67,341 
Total75,007 
Less: Unamortized debt discount and issuance cost(392)
Less: Unaccreted backend fee(1,690)
Less: Interest(13,400)
Term Loan$59,525 
v3.25.0.1
Common Stock
 12 Months Ended
Dec. 31, 2024
Equity [Abstract]  
Common Stock Common Stock
The Company’s Amended and Restated Certificate of Incorporation authorizes the Company to issue 200,000,000 shares of $0.001 par value common stock.
The holders of common stock are entitled to receive dividends whenever funds and assets are legally available and when declared by the Board of Directors. As of December 31, 2024 and December 31, 2023, no dividends had been declared.
As of December 31, 2024 and December 31, 2023, the Company had reserved common stock for future issuance as follows:
Year Ended December 31,
2024
2023
Outstanding options under the 2021 Plan1,987,784 2,208,341 
Shares available for future grant under the 2021 Plan2,201,012 1,314,502 
Outstanding options under the 2023 Inducement Plan380,424 380,424 
Outstanding restricted stock units under the 2021 Plan1,480,338 2,430,803 
Common stock available for ESPP475,416 399,798 
Total6,524,974 6,733,868 
v3.25.0.1
Stock Plans
 12 Months Ended
Dec. 31, 2024
Share-Based Payment Arrangement [Abstract]  
Stock Plans Stock Plans
2020 Stock Plan
In August 2020, the Company adopted the 2020 Stock Plan, or the 2020 Plan, which provides for the granting of stock options to employees, directors and consultants of the Company. Stock options granted under the 2020 Plan may be either incentive stock options, or ISOs, nonqualified stock options, or NSOs, stock appreciation rights, restricted stock awards, restricted stock unit awards or other stock awards. ISOs may only be granted to Company employees (including officers and directors who are also employees). Stock awards other than ISOs may be granted to company employees, directors and consultants.
The maximum term of each stock option grant is ten years. The exercise price of ISOs and NSOs granted to a 10% stockholder shall not be less than 110% of the estimated fair value of the shares on the date of grant as determined by the Company’s board of directors.
2021 Equity Incentive Plan
In April 2021, prior to the IPO closing, the Company’s board of directors and stockholders approved the 2021 Equity Incentive Plan, or the 2021 Plan, which became effective upon the IPO closing. The Company initially reserved 2,900,000 shares of common stock for issuance of share-based compensation awards, including ISOs, NSOs, stock appreciation rights, restricted stock units and other stock-based awards. ISOs may be granted only to Company employees (including officers and directors who are also employees). Shares of common stock subject to awards granted under the 2020 Plan that are forfeited or lapse unexercised will be available for issuance under the 2021 Plan. Once the 2021 Plan became effective, no further grants were made under the 2020 Plan.
Options under the 2021 Plan may be granted for periods of up to 10 years at exercise prices no less than the fair market value of the Company’s common stock on the date of grant; provided, however, that the exercise price of an ISO granted to a 10% stockholder may not be less than 110% of the fair market value of the shares on the date of grant and such option may not be exercisable after the expiration of five years from the date of grant. Vesting conditions determined by the plan administrator may apply to stock options and other stock-based awards and may include continued service, performance and/or other conditions. Generally, options and restricted stock units vest over a three or four-year period.
In January 2025, the number of shares of common stock available for issuance under the 2021 Plan was increased by 1,507,251 shares as a result of the automatic increase provision in the 2021 Plan.
A summary of shares available for grant under the 2021 Plan is as follows:
Shares Available for Grant
Shares available for grant as of January 1, 20231,443,946 
Authorized1,252,287 
Granted/Awarded(2,758,399)
Canceled1,322,669 
Withheld for taxes53,999 
Shares available for grant as of December 31, 2023
1,314,502 
Authorized1,391,173 
Granted/Awarded(1,157,793)
Canceled587,813 
Withheld for taxes65,317 
Shares available for grant as of December 31, 2024
2,201,012 
2023 Inducement Plan
In July 2023, the Company’s Compensation Committee of the Board of Directors approved the 2023 Inducement Plan, or the Inducement Plan. The terms of the Inducement Plan are similar to the terms of the 2021 Plan with the exception that incentive stock options may not be issued under the Inducement Plan and awards under the Inducement Plan may only be issued to eligible recipients under the applicable Nasdaq rules. The Inducement Plan was adopted by the Compensation Committee without stockholder approval pursuant to Rule 5635(c)(4) of the Nasdaq Listing Rules. The Company has initially reserved 380,424 shares of its common stock for issuance pursuant to awards granted under the Inducement Plan, and granted an option to purchase 380,424 shares of its common stock to its Chief Executive Officer, or CEO, as a material inducement for the CEO to join the Company.
A summary of stock option activity for the years ended December 31, 2024 and 2023 is set forth below:
Options Outstanding
Number of SharesWeighted-Average Exercise PriceWeighted Average Remaining Contractual Term (in Years)
Balances as of January 1, 20233,446,583 $3.61 8.06
Granted695,225 $3.85 
Exercised(889,968)$0.17 
Canceled(663,075)$5.00 
Balances as of December 31, 2023
2,588,765 $4.51 7.17
Granted510,654 $12.04 
Exercised(556,718)$1.45 
Canceled(174,493)$15.89 
Balances as of December 31, 2024
2,368,208 $6.01 7.27
Vested and exercisable at December 31, 2024
1,568,345 $4.51 6.49
Vested and expected to vest at December 31, 2024
2,368,208 $6.01 7.27
The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying stock options and the fair value of the Company’s common stock for stock options that were in-the-money at period end. The total intrinsic value of stock options exercised was $6.0 million and $5.3 million during the years ended December 31, 2024 and December 31, 2023, respectively, determined at the date of each stock option exercise.
Early Exercise of Stock Options
The terms of the Company’s 2020 Plan and 2021 Plan permit the exercise of options granted under the plans prior to vesting, subject to required approvals. The shares of common stock issued from the early exercise of unvested stock options are restricted and continue to vest over the original implied service period. The Company has the option to repurchase any unvested shares at the original purchase price upon any voluntary or involuntary termination. The shares purchased by the employees and non-employees pursuant to the early exercise of stock options are not deemed, for accounting purposes, to be outstanding until those shares vest. The cash received in exchange for exercised and unvested shares related to stock options granted is recorded as a liability for the early exercise of stock options in accrued liabilities on the accompanying balance sheet and will be transferred into common stock and additional paid-in capital as the shares vest. As of December 31, 2024 and December 31, 2023 there were 0 and 30,211 shares of common stock, respectively, issued pursuant to early exercised options and subject to repurchase.
Employee Stock Purchase Plan
In April 2021, the Company adopted the 2021 Employee Stock Purchase Plan, or ESPP. The Company allows eligible employees to purchase shares of the Company's common stock through payroll deductions at a price equal to 85% of the lesser of the fair market value of the stock as of the first date or the ending date of each offering period, which is typically six months. There were 580,000 shares of common stock initially reserved for issuance
under the ESPP. In January 2025, the number of shares of common stock available for issuance under the ESPP was increased by 301,450 shares as a result of the automatic increase provision in the ESPP.
The Company issued 202,616 and 280,599 shares under the ESPP for the years ended December 31, 2024 and December 31, 2023, respectively. As of December 31, 2024, 475,416 shares under the ESPP remain available for purchase. The offering period and purchase period is determined by the board of directors. A new offering period of six months has been authorized beginning December 7, 2024 through June 6, 2025.
Compensation expense is calculated using the fair value of the employees' purchase rights under the Black-Scholes model, which was estimated using the following assumptions:
Year Ended December 31,
2024
2023
Expected term (in years)0.50.5
Expected volatility
76% - 78%
63% - 90%
Weighted average risk-free interest rate
4.34% - 5.40%
5.36% - 5.43%
Fair value of common stock
$6.47 - $10.95
$4.20 - $8.49
Dividend yield—%—%

Restricted Stock Units
Activity with respect to restricted stock units, or RSUs, was as follows:
Number of Shares Underlying Outstanding Restricted Stock UnitsWeighted Average Grant Date Fair Value
Unvested, January 1, 20231,756,209 $10.15 
Granted2,063,174 $4.77 
Vested(728,986)$9.76 
Canceled(659,594)$7.14 
Unvested, December 31, 2023
2,430,803 $6.52 
Granted647,139 $13.00 
Vested(1,184,284)$6.65 
Canceled(413,320)$7.68 
Unvested, December 31, 2024
1,480,338 $8.92 
The fair value of RSUs is based on the Company’s closing stock price on the date of grant.
Stock-Based Compensation
The Company recognized stock-based compensation as follows (in thousands):
Year Ended December 31,
2024
2023
Cost of goods sold$723 $606 
Research and development3,270 2,749 
Selling, general and administrative6,289 6,203 
Total stock-based compensation$10,282 $9,558 
The above stock-based compensation expense related to the following equity-based awards (in thousands):
Year Ended December 31,
2024
2023
Stock options and restricted stock units$9,745 $9,271 
ESPP537 287 
Total stock-based compensation$10,282 $9,558 
As of December 31, 2024, the total unrecognized stock-based compensation expense related to unvested stock options and restricted stock units was $15.0 million, which will be amortized on a straight-line basis over a weighted average remaining period of 2.1 years.
As of December 31, 2024, the Company had unrecognized stock-based compensation expense relating to the ESPP awards of approximately $0.2 million, which is expected to be recognized over a weighted-average period of 0.4 years.
The total fair value of options that vested during the years ended December 31, 2024 and December 31, 2023 was $8.8 million and $7.8 million, respectively. The options granted during the years ended December 31, 2024 and December 31, 2023 had a weighted average grant date fair value of $8.13 per share and $3.85 per share, respectively.
The Company estimated the fair value of stock options using the Black-Scholes option pricing model. The fair value of employee stock options is being amortized on a straight-line basis over the requisite service period of the awards. The fair value of employee stock options was estimated using the following assumptions for the years ended December 31, 2024 and December 31, 2023:
Year Ended December 31,
2024
2023
Expected term (in years)
5.27 - 6.25
5.27 - 6.25
Expected volatility
71% - 78%
60% - 63%
Weighted average risk-free interest rate
3.62% - 4.64%
3.74% - 3.94%
Fair value of common stock
$6.00 - $17.11
$1.54 - $4.50
Dividend yield—%—%

The expected term of stock options represents the weighted-average period the stock options are expected to remain outstanding. The Company does not have sufficient historical exercise and post-vesting termination activity to provide accurate data for estimating the expected term of options and has opted to use the “simplified method,” whereby the expected term equals the arithmetic average of the vesting term and the original contractual term of the option. The expected stock price volatility assumption was determined by a combination of the Company’s historical stock trading volatility and the historical volatilities of industry peers, as the Company does not have sufficient trading history to solely rely on the volatility of its common stock. The Company will continue to analyze the historical stock price volatility and expected term assumptions as more historical data for the Company’s common stock becomes available. The risk-free interest rate assumption is based on the U.S. Treasury instruments whose term was consistent with the expected term of the Company’s stock options. The expected dividend assumption is based on the Company’s history and expectation of not to declare and pay dividends.
The fair value of the Company’s common stock is determined based on its closing market price on the date of grant.
The Company accounts for forfeitures as they occur.
v3.25.0.1
Income Taxes
 12 Months Ended
Dec. 31, 2024
Income Tax Disclosure [Abstract]  
Income Taxes Income Taxes
The Company’s operations and income tax components are solely in the United States. From inception through 2024, the Company has only generated pretax losses in the United States and has not generated any pretax income or
loss outside of the United States. The Company did not record a provision (benefit) for income taxes for the years ended December 31, 2024 and 2023. The Company accounts for income taxes in accordance with ASC 740, Income Taxes, which requires that the tax benefit of net operating losses, temporary differences and credit carryforwards be recorded as an asset to the extent that management assesses that realization is "more likely than not." Realization of the future tax benefits is dependent on the Company's ability to generate sufficient taxable income within the carryforward period. Because of the Company's recent history of operating losses, management believes that recognition of the deferred tax assets arising from the above-mentioned future tax benefits is currently not likely to be realized and, accordingly, has provided a full valuation allowance.
A reconciliation of the statutory U.S. federal rate to the Company’s effective tax rate is as follows:
December 31,
2024
2023
Tax at federal statutory rate21.0 %21.0 %
State taxes, net of federal benefit6.4 %4.5 %
Research and development tax credit5.1 %1.8 %
Stock-based compensation5.5 %(0.8)%
Nondeductible interest expense
(2.0)%(0.5)%
FIN 48 reserve(1.2)%(0.3)%
Change in valuation allowance(21.8)%(23.3)%
Federal net operating loss expiration(10.2)%— %
Other(2.8)%(2.4)%
Total — %— %
The tax effects of temporary differences that give rise to significant components of the deferred tax assets and liabilities are as follows (in thousands):
December 31,
2024
2023
Deferred tax assets:
Net operating loss carryforwards$42,043 $41,864 
Research and development credits14,903 13,069 
Research and development expenditures, capitalized for tax12,283 8,271 
Fixed assets and inventory28 151 
Accruals and reserves1,399 1,633 
Interest expense carryforward5,747 5,033 
Operating lease liability3,515 3,958 
Other1,281 1,718 
Gross deferred tax assets81,199 75,697 
Deferred tax liabilities:
Operating lease right-of-use asset(3,014)(3,436)
Total deferred tax liabilities(3,014)(3,436)
Valuation allowance(78,185)(72,261)
Net deferred tax assets$— $— 
Beginning January 1, 2022, the Tax Cuts and Jobs Act, or the Tax Act, eliminated the option to deduct research and development expenditures in the current year and requires taxpayers to capitalize such expenses pursuant to Internal Revenue Code Section 174. The capitalized expenses are amortized over a 5-year period for domestic expenses and a 15-year period for foreign expenses. As a result of this provision of the Tax Act, deferred tax assets related to capitalized research expenses increased by $12.3 million.
We recognize deferred income taxes for temporary differences between the basis of assets and liabilities for financial statement and income tax purposes, as well as for tax attribute carryforwards. We regularly evaluate the
positive and negative evidence in determining the realizability of our deferred tax assets. Based upon the weight of available evidence, which includes our historical operating performance and reported cumulative net losses since inception, we maintained a full valuation allowance on the net deferred tax assets as of December 31, 2024 and 2023. We intend to maintain a full valuation allowance on our deferred tax assets until sufficient positive evidence exists to support reversal of the valuation allowance. The valuation allowance increased by $5.9 million during the year ended December 31, 2024 primarily resulting from $5.5 million increase in gross deferred tax assets net of a $0.4 million decrease in deferred tax liabilities. The valuation allowance increased by $7.5 million during the year ended December 31, 2023 primarily resulting from $7.0 million increase in gross deferred tax assets net of a $0.5 million decrease in deferred tax liabilities.
As of December 31, 2024, the Company had net operating loss, or NOL, carryforwards of $152.5 million and $162.7 million available to reduce future taxable income, if any, for federal and state income tax purposes, respectively. The federal and state NOL carryforwards begin expiring in 2026 and 2029, respectively. As of December 31, 2024, the amount of federal NOL carryforwards that does not expire is $114.0 million (subject to certain utilization limitations).
As of December 31, 2024, the Company had research and development credit carryforwards of $5.4 million and $14.2 million available to reduce future taxable income, if any, for federal and state income tax purposes, respectively. The federal credit carryforwards begin expiring in 2037 and the state credits carryforward indefinitely.
Utilization of the Company’s NOL and tax credit carryforwards may be subject to a substantial annual limitation due to the ownership change provisions included in the Internal Revenue Code, or Section 382, and similar state provisions. An annual limitation may result in the expiration of NOL and credit carryforwards before utilization. The Company conducted Section 382 studies as of 2016, 2021, and 2024, and has determined that it experienced Section 382 ownership changes in 2016 and in 2021, and no change in 2024. The 2016 ownership change resulted in permanent limitations of its NOL and credit carryforwards. The 2021 ownership change did not result in permanent limitations of its NOL or credit carryforwards. It has been determined that $226.8 million and $150.7 million of federal and state NOL carryforwards, respectively, have been permanently limited and will expire unutilized. It has also been determined that $10.4 million of federal research and development credits have been permanently limited and will expire unutilized. The gross deferred tax assets disclosed above exclude NOL and credit carryforwards that are expected to expire due to the Section 382 limitation.
The American Rescue Plan Act of 2021 was signed into law on March 11, 2021 expanding the definition of covered employees as defined under Section 162(m). The provisions under the expanded definition of covered employees did not have a material impact on the Company’s tax positions for the year ended December 31, 2023 or 2024.
California Assembly Bill 85 (AB 85) was signed into law by Governor Gavin Newsom on June 29, 2020. The legislation suspends the California NOL deductions for 2020, 2021, and 2022 for certain taxpayers and imposes a limitation on certain California tax credits for 2020, 2021, and 2022. The legislation disallows the use of California NOL deductions if the taxpayer recognizes business income and its adjusted gross income is greater than $1,000,000. The carryover periods for NOL deductions disallowed by this provision will be extended. Additionally, any business credit will only offset a maximum of $5,000,000 of California tax. Given the Company’s taxable loss position, this legislation did not impact the tax provision for the years ended December 31, 2023 or 2024.
California Senate Bill 113 (SB 113), was signed into law by Governor Newsom on February 9, 2022. The legislation contains important California tax law changes, including reinstatement of business tax credits and net NOL deductions limited by AB 85 mentioned above. The new tax law should be accounted for under ASC 740 in the period of enactment (2022) but is not expected to have a material impact on the Company’s tax provision due to its taxable loss position.
On August 16, 2022, the President signed into law H.R. 5376, or the Inflation Reduction Act of 2022. The primary tax provisions in the new law include an alternative minimum tax on certain large corporations, a tax on stock buybacks and certain energy-related tax credits, each of which become effective after December 31, 2022. The
provisions of the Inflation Reduction Act of 2022 does not have a material impact on the Company’s financial statements and related disclosures.
As of December 31, 2024, the Company had unrecognized tax benefits of $2.1 million related to $5.4 million and $14.2 million of federal and state research and development tax credit carryforwards, respectively. The unrecognized tax benefits, if recognized, would not have an impact on the Company's effective tax rate, due to the valuation allowance. It is unlikely that the amount of unrecognized tax benefits will significantly change over the next twelve months. No liability related to uncertain tax positions is recorded in the financial statements.
A reconciliation of the beginning and ending unrecognized tax benefit amount is as follows (in thousands):
Year Ended December 31,
2024
2023
Beginning balance$1,730 $1,601 
Increase in balance related to tax positions taken during the current year355 136 
Decrease in balance related to tax positions taken during prior years— (7)
Ending balance$2,085 $1,730 
It is the Company’s policy to include penalties and interest expense related to income taxes as a component of other expense and interest expense, respectively, as necessary. The Company determined that no accrual for interest and penalties related to unrecognized tax benefits was required as of December 31, 2024 and December 31, 2023.
All of the Company’s tax years will remain open for examination by the federal and state authorities for 3 and 4 years, respectively, from the date of utilization of its tax attributes.
v3.25.0.1
Net Loss per Share Attributable to Common Stockholders
 12 Months Ended
Dec. 31, 2024
Earnings Per Share [Abstract]  
Net Loss per Share Attributable to Common Stockholders Net Loss per Share Attributable to Common Stockholders
The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders (in thousands, except for share and per share amounts):
Year Ended December 31,
2024
2023
Numerator:
Net loss attributable to common stockholders$(27,141)$(32,956)
Denominator:
Weighted-average common stock outstanding used to compute basic and diluted net loss per share29,126,314 25,851,813 
Net loss per share attributable to common stockholders, basic and diluted$(0.93)$(1.27)
The following potentially dilutive securities outstanding have been excluded from the computation of diluted weighted average shares outstanding because such securities have an antidilutive impact due to the Company’s net loss, in common stock equivalent shares:
December 31,
2024
2023
Options to purchase common stock2,368,208 2,588,765 
Unvested restricted stock units1,480,338 2,430,803 
Shares committed under ESPP68,138 81,102 
Unvested early exercised common stock options— 30,211 
Total Shares3,916,684 5,130,881 
v3.25.0.1
Segment Information
 12 Months Ended
Dec. 31, 2024
Segment Reporting [Abstract]  
Segment Information Segment Information
The Company operates as one operating and reportable segment. All of the Company’s long-lived assets, comprised of property and equipment, are based in the United States. All of the Company’s revenue, with the exception of $0.2 million and less than $0.1 million, was in the United States for the years ended December 31, 2024 and 2023, respectively, based on the shipping location of the external customer.
The Company’s CODM is our Chief Executive Officer. Our CODM makes decisions on resource allocation, evaluates operating performance, and monitors budget versus actual results using net loss. In addition to the significant expense categories included within net loss presented on the Company’s Statements of Operations and Comprehensive Loss, disaggregated amounts that comprise selling, general and administrative expenses are as follows (in thousands):
Year Ended December 31,
2024
2023
Sales and marketing expense$39,669 $35,487 
General and administrative expense17,434 19,031 
Total selling, general and administrative expense$57,103 $54,518 
Other segment items within net loss include interest income, interest expense, and other income (expense), net.
v3.25.0.1
Subsequent Events
 12 Months Ended
Dec. 31, 2024
Subsequent Events [Abstract]  
Subsequent Events Subsequent Events
In February 2025, the Company completed a follow-on offering of 7,475,000 shares of the Company’s common stock, including 975,000 shares from the exercise of the underwriters’ option to purchase additional shares, at an offering price of $10.00 per share. The aggregate net proceeds to the Company from the follow-on offering were approximately $69.8 million after deducting underwriting discounts and commissions and estimated offering expenses. The Company used $49.5 million of the net proceeds to repurchase all of the 5,270,845 shares held by our significant stockholder, KCK Ltd., at $9.40 per share. The repurchased shares became authorized but unissued shares.
In February 2025, the Company terminated its Sales Agreement with Leerink and closed the ATM program. On the date of termination, the Company had $38.3 million remaining under the ATM program.
v3.25.0.1
Pay vs Performance Disclosure - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Pay vs Performance Disclosure    
Net loss $ (27,141) $ (32,956)
v3.25.0.1
Insider Trading Arrangements
 3 Months Ended
Dec. 31, 2024
Trading Arrangements, by Individual  
Rule 10b5-1 Arrangement Adopted false
Non-Rule 10b5-1 Arrangement Adopted false
Rule 10b5-1 Arrangement Terminated false
Non-Rule 10b5-1 Arrangement Terminated false
v3.25.0.1
Insider Trading Policies and Procedures
 12 Months Ended
Dec. 31, 2024
Insider Trading Policies and Procedures [Line Items]  
Insider Trading Policies and Procedures Adopted true
v3.25.0.1
Cybersecurity Risk Management and Strategy Disclosure
 12 Months Ended
Dec. 31, 2024
Cybersecurity Risk Management, Strategy, and Governance [Line Items]  
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]
We have implemented and maintain various information security processes designed to identify, assess, and manage material risks from cybersecurity threats to our critical computer networks, third-party hosted services, communications systems, hardware and software, and our critical data, including intellectual property, confidential information that is proprietary, strategic or competitive in nature, client data and patient data, or, collectively, Information Systems and Data.
Our information security function is overseen by our Privacy and Security Officer and is supported by our Director of Information Technology and Chief of Operations and Development, as well as our engineering operations and third-party service providers. This function helps to identify, assess, and manage our cybersecurity threats and risks, including through the use of our risk register. Our information security function helps identify and assess risks from cybersecurity threats by monitoring and evaluating our threat environment using various methods including, for example: evaluating our industry’s risk profile, deploying manual and automated tools in certain environments, subscribing to reports and services that identify certain cybersecurity threats, evaluating certain threats reported to us, engaging third parties to conduct threat assessments, conducting internal and external vulnerability and threat scans and assessments of certain environments, conducting internal audits, and penetration testing of certain systems.
Depending on the environment, we implement and maintain various technical, physical, and organizational measures, processes, standards, and policies designed to manage and mitigate material risks from cybersecurity threats to our Information Systems and Data, including, for example: incident detection and response, vulnerability management and disaster recovery policies, risk assessments, data encryption and data segregation of certain data, access controls and network security controls in certain environments, physical security controls, employee training, phishing simulation exercises, penetration testing, systems monitoring, cybersecurity insurance and asset and vendor management programs.
Our assessment and management of material risks from cybersecurity threats are integrated into our overall risk management processes. For example, our Privacy and Security Officer works with Information Technology, Legal, and other NeuroPace leadership to prioritize our risk management processes and mitigate cybersecurity threats that are more likely to lead to a material impact to our business.
We use third-party service providers to assist us from time to time to identify, assess, and manage material risks from cybersecurity threats, including for example: professional service firms, including outside legal counsel, threat intelligence service providers, cybersecurity consultants, cybersecurity service provider, and penetration testing firms.
We use third-party service providers to perform a variety of functions throughout our business, such as application providers and hosting companies. We have a vendor management program to manage cybersecurity risks associated with our use of these providers. The program includes security questionnaires and risk assessments for certain vendors, vulnerability scans for certain vendors, security assessment calls with certain vendor’s security personnel, imposition of information security contractual obligations on certain vendors, verification of relevant industry standard security certifications for certain vendors, and other vendor management program elements. Depending on the nature of the services provided, the sensitivity of the Information Systems and Data at issue, and the identity of the provider, our vendor management process may involve different levels of assessment designed to help identify cybersecurity risks associated with a provider and impose contractual obligations related to cybersecurity on the provider.
For a description of the risks from cybersecurity threats that may materially affect us and how they may do so, see our risk factors under the section titled “Risks related to privacy, information technology and cybersecurity” located in Part 1. Item 1A. Risk Factors in this Annual Report on Form 10-K.
Cybersecurity Risk Management Processes Integrated [Flag] true
Cybersecurity Risk Management Processes Integrated [Text Block] We have implemented and maintain various information security processes designed to identify, assess, and manage material risks from cybersecurity threats to our critical computer networks, third-party hosted services, communications systems, hardware and software, and our critical data, including intellectual property, confidential information that is proprietary, strategic or competitive in nature, client data and patient data, or, collectively, Information Systems and Data.
Cybersecurity Risk Management Third Party Engaged [Flag] true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag] true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag] false
Cybersecurity Risk Board of Directors Oversight [Text Block]
Governance
Our board of directors addresses our cybersecurity risk management as part of its general oversight function. The board of directors’ audit committee is responsible for overseeing our cybersecurity risk management processes, including oversight and mitigation of risks from cybersecurity threats.
Our cybersecurity risk assessment and management processes are implemented and maintained by certain NeuroPace management, including our Privacy and Security Officer, who has more than 20 years of experience in healthcare privacy and security, in coordination with our Director of Information Technology, who has more than 30 years of experience with information technology operations and seventeen years as a corporate privacy and security officer.
Our Privacy and Security Officer, Director of Information Technology, and NeuroPace leadership are responsible for hiring appropriate personnel, helping to integrate cybersecurity risk considerations into our overall risk management strategy, and communicating key priorities to relevant personnel. Our Privacy and Security Officer in coordination with our Director of Information Technology is responsible for approving budgets, helping prepare for cybersecurity incidents, approving cybersecurity processes, and reviewing security assessments and other security-related reports.
Our incident response and vulnerability management policies are designed to escalate certain cybersecurity incidents to members of management depending on the circumstances, including our Privacy and Security Officer, Director of Information Technology, Chief of Operations and Development and other designated individuals. Our Privacy and Security Officer works with our incident response team to help us mitigate and remediate cybersecurity incidents of which they are notified. In addition, our incident response and vulnerability management policies include reporting to the audit committee of the board of directors for certain cybersecurity incidents.
The board of directors receives periodic reports from our Privacy and Security Officer concerning significant cybersecurity threats to us and risk and the processes we have implemented to address them. The board of directors also has access to various reports, summaries or presentations related to cybersecurity threats, risk and mitigation.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]
The board of directors receives periodic reports from our Privacy and Security Officer concerning significant cybersecurity threats to us and risk and the processes we have implemented to address them. The board of directors also has access to various reports, summaries or presentations related to cybersecurity threats, risk and mitigation.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block] The board of directors receives periodic reports from our Privacy and Security Officer concerning significant cybersecurity threats to us and risk and the processes we have implemented to address them. The board of directors also has access to various reports,
Cybersecurity Risk Role of Management [Text Block]
Our board of directors addresses our cybersecurity risk management as part of its general oversight function. The board of directors’ audit committee is responsible for overseeing our cybersecurity risk management processes, including oversight and mitigation of risks from cybersecurity threats.
Our cybersecurity risk assessment and management processes are implemented and maintained by certain NeuroPace management, including our Privacy and Security Officer, who has more than 20 years of experience in healthcare privacy and security, in coordination with our Director of Information Technology, who has more than 30 years of experience with information technology operations and seventeen years as a corporate privacy and security officer.
Cybersecurity Risk Management Positions or Committees Responsible [Flag] true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]
Our board of directors addresses our cybersecurity risk management as part of its general oversight function. The board of directors’ audit committee is responsible for overseeing our cybersecurity risk management processes, including oversight and mitigation of risks from cybersecurity threats.
Our cybersecurity risk assessment and management processes are implemented and maintained by certain NeuroPace management, including our Privacy and Security Officer, who has more than 20 years of experience in healthcare privacy and security, in coordination with our Director of Information Technology, who has more than 30 years of experience with information technology operations and seventeen years as a corporate privacy and security officer.
Our Privacy and Security Officer, Director of Information Technology, and NeuroPace leadership are responsible for hiring appropriate personnel, helping to integrate cybersecurity risk considerations into our overall risk management strategy, and communicating key priorities to relevant personnel. Our Privacy and Security Officer in coordination with our Director of Information Technology is responsible for approving budgets, helping prepare for cybersecurity incidents, approving cybersecurity processes, and reviewing security assessments and other security-related reports.
Our incident response and vulnerability management policies are designed to escalate certain cybersecurity incidents to members of management depending on the circumstances, including our Privacy and Security Officer, Director of Information Technology, Chief of Operations and Development and other designated individuals. Our Privacy and Security Officer works with our incident response team to help us mitigate and remediate cybersecurity incidents of which they are notified. In addition, our incident response and vulnerability management policies include reporting to the audit committee of the board of directors for certain cybersecurity incidents.
The board of directors receives periodic reports from our Privacy and Security Officer concerning significant cybersecurity threats to us and risk and the processes we have implemented to address them. The board of directors also has access to various reports, summaries or presentations related to cybersecurity threats, risk and mitigation.
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]
Our cybersecurity risk assessment and management processes are implemented and maintained by certain NeuroPace management, including our Privacy and Security Officer, who has more than 20 years of experience in healthcare privacy and security, in coordination with our Director of Information Technology, who has more than 30 years of experience with information technology operations and seventeen years as a corporate privacy and security officer.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]
The board of directors receives periodic reports from our Privacy and Security Officer concerning significant cybersecurity threats to us and risk and the processes we have implemented to address them. The board of directors also has access to various reports, summaries or presentations related to cybersecurity threats, risk and mitigation.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag] true
v3.25.0.1
Summary of Significant Accounting Policies (Policies)
 12 Months Ended
Dec. 31, 2024
Accounting Policies [Abstract]  
Basis of Presentation
Basis of Presentation
The financial statements have been prepared in conformity with generally accepted accounting principles in the United States, or GAAP, as defined by the Financial Accounting Standards Board, or the FASB.
Use of Estimates
Use of Estimates
The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the amounts and disclosures reported in the financial statements. The Company uses significant judgment when making estimates related to the provision for excess and obsolete inventories. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may ultimately materially differ from these estimates and assumptions.
Revenue Recognition
Revenue Recognition
The Company derives most of its revenue from sales of RNS Systems to hospital facilities (typically comprehensive epilepsy centers, or Level 4 CECs) that implant its products. Beginning in the fourth quarter of 2022, the Company also derives revenue from sales of DIXI Medical products, primarily to its current customer base. Beginning in the fourth quarter of 2023, the Company also derives revenue from services provided to Rapport Therapeutics, Inc., or Rapport.
The Company recognizes revenue in accordance with ASC 606, Revenue from Contracts with Customers. Under ASC 606, revenue is recognized when a customer obtains control of promised goods or services, in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, the Company performs the following five steps:
i.identify the contract(s) with a customer;
ii.identify the performance obligations in the contract;
iii.determine the transaction price;
iv.allocate the transaction price to the performance obligations in the contract; and
v.recognize revenue when (or as) the entity satisfies a performance obligation.
At contract inception, the Company assesses the products or services promised within each contract and determines those that are performance obligations. The Company’s contracts with customers for the RNS System often include a promise to transfer products, as well as an implied promise to provide a service to the customer, which is access to the Company’s Patient Data Management System, or PDMS, and nSight Platform. The Company has concluded that the RNS System and its related products represent a single performance obligation, as the customer cannot benefit from the products individually, and that access to the PDMS and nSight Platform represent separate performance obligations, as the clinicians can utilize them with other components of the RNS System that are readily available.
The Company determines the transaction price based on the amount it expects to be entitled to in exchange for transferring the promised product or service to the customer, which is based on the invoiced price for the products or services. All prices are at fixed amounts per the sales agreement with the customer and there are no discounts, rebates or other price concessions.
When a contract contains multiple performance obligations, the Company allocates the transaction price to each performance obligation based on its relative standalone selling price. Standalone selling prices are based on observable prices at which the Company separately sells its products or services. If a standalone selling price is not directly observable, the Company estimates the standalone selling price considering market data, cost, gross margin, and other available information.
The Company typically delivers its RNS System and related products to a hospital on the date of the scheduled procedure. There is no commitment or contract until the delivery of the product and the procedure may be canceled
at any time. Once the device has been implanted in or otherwise provided to a patient, the customer is considered to have accepted the delivery (i.e., has approved the contract) and both parties are committed to perform their respective obligations. Assuming all other revenue recognition criteria are met, the Company recognizes revenue from the sale of its RNS System and related products at a point in time when the procedure is completed and the device is implanted in a patient.
The Company also ships the RNS System and related products to customers who place orders ahead of scheduled procedures. Such orders or contracts generally include a promise to transfer products only. As such, the Company recognizes revenue from these orders or contracts at a point in time when the customer obtains control of the products.
The Company recognizes service revenue related to the PDMS and the nSight Platform on a ratable basis over the period in which the Company expects to provide access to clinicians. The Company has concluded that such service revenue is immaterial.
The Company’s contracts with customers for DIXI Medical products generally include a promise to transfer products only. As such, the Company recognizes revenue from the sale of DIXI Medical products at a point in time when the customer obtains control of the products.
The Company recognizes revenue under its contract with Rapport to provide biomarker monitoring and data analysis services. Revenue from biomarker monitoring is recognized ratably over the two-year contractual support period, as the benefits provided by the Company’s performance are simultaneously consumed by the customer. Revenue related to data analysis is recognized upon completion of the services. The Company’s contract with Rapport commenced during the fourth quarter of 2023. The related revenue recognized for the years ended December 31, 2024 and 2023 were $1.2 million and $0.4 million, respectively.
The Company recognizes revenue for arrangements where it has satisfied its performance obligations but has not issued invoices. These amounts are recorded as unbilled receivables, which are included in accounts receivable on the balance sheet, as the Company has an unconditional right to payment at the end of the applicable period.
Payment terms are typically 30 days from the fulfillment of the orders and fall within the one-year guidance for the practical expedient which allows the Company to forgo adjustment of the promised amount of consideration for the effects of a significant financing component. Sales taxes that are collected from customers and remitted to governmental authorities are accounted for on a net basis and therefore are excluded from net sales, however, most of the Company’s sales are tax exempt. The Company believes that collection is probable as it has no history of uncollectible accounts and the customers are large, creditworthy institutions.
As allowed under the practical expedient, the Company does not disclose the value of unsatisfied performance obligations for contracts with an original expected length of one year or less. Costs associated with product sales include commissions, where the Company applies the practical expedient and recognizes commissions as expense when incurred because the expense is incurred over a period of time of less than one year. Commissions are reported in selling, general and administrative expense in the statements of operations and comprehensive loss.
Fair Value of Financial Instruments
Fair Value of Financial Instruments
Carrying amounts of certain of the Company’s financial instruments, including cash equivalents, accounts receivable, accounts payable and accrued liabilities, approximate fair value because of the short-term nature of these instruments. The Company has a short-term investment in a fixed income mutual fund, which is classified as equity security and carried at fair value based on quoted market prices. Changes in the fair value of the short-term investment are recorded in income or loss. The Company believes that its borrowings bear interest at the prevailing market rates for instruments with similar characteristics; accordingly, the carrying value of this instrument approximates its fair value. The Company determines the fair value of financial and non-financial assets and liabilities using the fair value hierarchy which establishes three levels of inputs that may be used to measure fair value
The Company measures certain financial assets and liabilities at fair value on a recurring basis. Fair value is an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or a liability. A three-tier fair value hierarchy is established as a basis for considering such assumptions and for inputs used in the valuation methodologies in measuring fair value:
Level 1Quoted prices in active markets for identical assets or liabilities.
Level 2Observable inputs other than Level 1 prices such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.
Level 3Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.
Cash and Cash Equivalents
Cash and Cash Equivalents
The Company considers all highly liquid investments with original maturities of three months or less at the time of purchase to be cash equivalents. Cash equivalents that are available-for-sale investments are recorded at fair value, based on quoted market prices. As of December 31, 2024 and December 31, 2023, the Company’s cash equivalents are entirely comprised of investments in money market funds.
Restricted Cash
Restricted Cash
Restricted cash is comprised of cash that is restricted as to withdrawal or use under the terms of certain contractual agreements. Restricted cash for the years ended December 31, 2024 and December 31, 2023 consists of collateral for the amended letter of credit that was issued in connection with the Company’s facility lease
Concentration of Credit Risk, and Other Risks and Uncertainties
Concentration of Credit Risk, and Other Risks and Uncertainties
Financial instruments that potentially subject the Company to credit risk consist of cash and cash equivalents, short-term investments and accounts receivable to the extent of the amounts recorded on the balance sheets. The Company’s cash is invested in major financial institutions in the United States. Deposits in these financial institutions may exceed federally insured limits, and the Company is exposed to credit risk on deposits in the event of default of the financial institutions to the extent account balances exceed the amount insured by the Federal Deposit Insurance Corporation. The Company’s cash equivalents are invested in money market funds.
The Company’s accounts receivable, with the exception of $0.1 million, are due from a variety of health care organizations in the United States. For the years ended December 31, 2024 and December 31, 2023, there were no customers that represented 10% or more of revenue. As of December 31, 2024 and December 31, 2023, no customer represented 10% or more of the Company’s accounts receivable.
Accounts Receivable
Accounts Receivable
Accounts receivable are recorded at the invoiced amount and do not bear interest. The Company makes estimates on the collectability of customer accounts based primarily on analysis of historical trends and experience, the age of the receivable and changes in customers’ financial condition. The Company uses its judgment, based on the best available facts and circumstances, and records an allowance against amounts due to reduce the receivable to the amount that is expected to be collected. The Company determined that no allowance was required as of December 31, 2024 and December 31, 2023. To date, the Company has not experienced any material credit-related losses.
Inventories
Inventories
Inventories are valued at the lower of cost or net realizable value. Cost is determined using the first-in, first-out method for all inventories. Net realizable value is determined as the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal and transportation. The Company regularly reviews inventory quantities in consideration of actual loss experiences, projected future demand, and remaining shelf life to record a provision for excess and obsolete inventory when appropriate. The Company’s policy is to
write down inventory that has become obsolete, inventory that has a cost basis in excess of its expected lower of cost or net realizable value, and inventory in excess of expected requirements. The estimate of excess quantities is judgmental and primarily dependent on the Company’s estimates of future demand for a particular product. If the estimate of future demand is too high, the Company may have to increase the reserve for excess inventory for that product and record a charge to the cost of goods sold. Inventory write-downs were $0.3 million and $0.2 million for the years ended December 31, 2024 and December 31, 2023, respectively.
Property and Equipment, net
Property and Equipment, net
Property and equipment, net is stated at cost less accumulated depreciation. Depreciation is calculated using the straight-line method over the estimated useful lives of the assets, generally three to five years. Leasehold improvements are amortized using the straight-line method over the shorter of the assets’ estimated useful lives or the remaining term of the lease. When assets are retired or otherwise disposed of, the cost and accumulated depreciation are removed from the balance sheet, and any resulting gain or loss is reflected in operations in the period realized. Maintenance and repairs are charged to operations as incurred.
Impairment of Long-Lived Assets
Impairment of Long-Lived Assets
The Company reviews long-lived assets, including property and equipment, for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If indicators of impairment exist, an impairment loss would be recognized when estimated undiscounted future cash flows expected to result from the use of the assets and their eventual disposition are less than their carrying amount. Impairment, if any, is measured as the amount by which the carrying amount of the long-lived assets exceeds their fair value.
Leases
Leases
The Company determines if an arrangement is a lease, or contains a lease, at inception. Operating leases are included in operating lease right-of-use, or ROU, assets, operating lease liability, and operating lease liability, net of current portion on the Company’s balance sheets.
ROU assets and lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. Since the Company’s lease does not provide an implicit rate, the Company uses its incremental borrowing rate based on the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term and in a similar economic environment at commencement date in determining the present value of future payments. The ROU asset also includes any lease payments made to the lessor at or before the commencement date, minus lease incentives received, and initial direct costs incurred. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. The Company elected certain practical expedients under ASC 842, Leases, including the package of practical expedients, which among other things, allowed the Company to carry forward prior conclusions about lease identification and classification, as well as elections to not record leases with an initial term of twelve months or less on the balance sheet, and to combine the lease and non-lease components in determining the lease liabilities and ROU assets.
Deferred Offering Costs
Deferred Offering Costs
The Company capitalizes, within other assets, certain legal, accounting and other third-party fees that are directly related to the Company’s in-process equity financings, including its ATM offering, until such financings are consummated. After consummation of the equity financing, these costs are recorded as a reduction of the proceeds received as a result of the offering. Should a planned equity financing be abandoned, terminated or significantly delayed, the deferred offering costs are immediately written off to operating expenses.
Government Programs and Research and Development Expenditures
Government Programs
In May 2021, the Company was awarded a grant by the National Institutes of Health, or NIH, to support research of thalamocortical responsive neurostimulation for the treatment of Lennox-Gastaut Syndrome, a type of epilepsy. The award was issued for a five-year period and has a total budget of over $9.3 million, which includes approximately $5.5 million in funding for subawards to third-party academic epilepsy centers that are collaborating on the study and are subinvestigators on the study funded by NIH. The subawardees are determined by NIH. The Company’s responsibility for the subawards is to submit the funding requests on behalf of the subawardees. The funding of subawards does not have any impact on the Company’s financial statements. Initially funding was approved for the first year beginning June 1, 2021 and provides for reimbursement of qualified direct and indirect expenses in the amount of $0.8 million, including $0.4 million for subawards. Approvals of funds for years two through five are subject to the completion of certain milestones. On July 30, 2022, the Company received funding approval for year two in the amount of $2.6 million, which includes $1.6 million for subawards. On May 25, 2023, the Company received funding approval for year three in the amount of $3.0 million, which includes $1.5 million for subawards. On July 22, 2024, the Company received funding approval for year four in the amount of $1.7 million, which includes $1.0 million for subawards.
For funds received under the NIH funding agreement, the Company recognizes a reduction in research and development expenses in an amount equal to the qualifying expenses incurred in each period up to the amount awarded by the NIH. The Company received $1.7 million and $1.4 million in funding during the years ended December 31, 2024 and 2023, respectively. Through December 31, 2024, $3.8 million of qualifying expenses have been incurred and funded by the NIH related to the first to fourth year of funding.
Qualifying expenses incurred by the Company in advance of funding by the NIH are recorded within prepaid expenses and other current assets on the balance sheets. As of December 31, 2024, the Company recorded prepaid expenses and other current assets of less than $0.1 million related to the fourth year of funding.
Research and Development Expenditures
The Company expenses research and development costs as incurred. Research and development expenses consist primarily of engineering, product development, clinical studies to develop and support the Company’s products, regulatory expenses, medical affairs and other costs associated with products and technologies that are in development, including quality assurance. Research and development expenses include employee compensation, including stock-based compensation, supplies, consulting, prototyping, testing, materials, travel expenses, depreciation and an allocation of facility overhead expenses. Additionally, research and development expenses
include costs associated with clinical studies including clinical trial design, clinical site reimbursement, data management, travel expenses, the cost of products used for clinical trials and costs associated with regulatory compliance and submitting and maintaining regulatory filings.
Warranty
Warranty
Warranty costs are accrued based on the Company’s best estimates when management determines that it is probable a charge or liability has been incurred and the amount of loss can be reasonably estimated. While the Company believes that historical experience provides a reliable basis for estimating such warranty cost, unforeseen quality issues or component failure rates could result in future costs in excess of such estimates.
Cost of Goods Sold
Cost of Goods Sold
The Company manufactures its products at its facility. Cost of goods sold consists primarily of costs related to materials, components and subassemblies, manufacturing overhead, direct labor, and reserves for excess and obsolete inventories. A significant portion of the Company’s cost of goods sold currently consists of manufacturing overhead costs. These overhead costs include the cost of facilities, material procurement, inventory control, quality assurance, equipment and operating supervision and management. Cost of goods sold also includes depreciation expense for production equipment and certain direct costs such as shipping costs. Shipping and handling costs are considered a fulfillment activity and are included in cost of goods sold as incurred.
Advertising Costs
Advertising Costs
The Company expenses advertising costs as incurred. Advertising costs include design and production costs, including website development, physician and patient testimonial videos, written media campaigns, and other items.
Stock-Based Compensation
Stock-Based Compensation
The Company accounts for stock-based employee compensation in accordance with ASC 718, Stock Compensation. ASC 718 requires the measurement of compensation based on the grant date fair value of the stock option or restricted stock unit (see Note 8). The Company amortizes the fair value of each award on a straight-line basis over the requisite service period of the award.
Income Taxes
Income Taxes
The Company accounts for income taxes under the asset and liability method. Under this method, deferred tax assets and liabilities are determined based on the difference between the financial statement and tax bases of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to affect taxable income. Valuation allowances are established when necessary to reduce deferred tax assets to the amounts expected to be realized.
The Company assesses all material positions taken in any income tax return, including all significant uncertain positions, in all tax years that are still subject to assessment or challenge by relevant taxing authorities. Assessing an uncertain tax position begins with the initial determination of the position’s sustainability and is measured at the largest amount of benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement. As of each balance sheet date, unresolved uncertain tax positions must be reassessed, and the Company will determine whether (i) the factors underlying the sustainability assertion have changed and (ii) the amount of the recognized tax benefit is still appropriate. The recognition and measurement of tax benefits requires significant judgment. Judgments concerning the recognition and measurement of a tax benefit might change as new information becomes available.
Net Loss per Share Attributable to Common Stockholders
Net Loss per Share Attributable to Common Stockholders
Basic net loss per common share is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period, without consideration of potentially dilutive securities. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. For purposes of the diluted net loss per share calculation, stock options, common stock subject to repurchase related to early exercise of stock options, and restricted stock units are considered to be potentially dilutive securities. Basic and diluted net loss attributable to common stockholders per share is presented in conformity with the two-class method required for participating securities. The Company considers the shares issued upon the early exercise of stock options subject to repurchase to be participating securities, because holders of such shares have non-forfeitable dividend rights in the event a dividend is paid on common stock. The holders of the shares issued upon early exercise of stock options subject to repurchase do not have a contractual obligation to share in the Company’s losses. As such, the net loss was attributed entirely to common stockholders. Because the Company has reported a net loss for all periods presented, diluted net loss per common share is the same as basic net loss per common share for those periods.
Jobs Act Accounting Election
JOBS Act Accounting Election
The Company is an emerging growth company, as defined in the Jumpstart Our Business Startups Act of 2012, or the JOBS Act. Under the JOBS Act, emerging growth companies can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date the Company (i) is no longer an emerging growth company or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these financial statements may not be comparable to companies that comply with new or revised accounting pronouncements as of public company effective dates.
Recent Accounting Pronouncements and Recent Accounting Pronouncements Not Yet Adopted
Recent Accounting Pronouncements
Recently Adopted Accounting Pronouncements
In accordance with Accounting Standards Codification, or ASC, 280, Segment Reporting, the Company operates as one operating and reportable segment. In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures. The amended guidance requires all public entities, including public entities with a single reportable segment, to disclose in interim and annual periods significant segment expenses that are regularly provided to the chief operating decision maker, or CODM, to allocate resources and assess performance, as well as the aggregate amount of other segment items included in the reported measure of segment profit or loss. The Company adopted this ASU effective for the fiscal year ended December 31, 2024 on a retrospective basis. Refer to Note 11 for further information on the Company’s reportable segment.
Recent Accounting Pronouncements Not Yet Adopted
In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures. This ASU requires greater disaggregation of information about a reporting entity's effective tax rate reconciliation as well as information on income taxes paid. This ASU applies to all entities subject to income taxes and is intended to help investors better understand an entity’s exposure to potential changes in jurisdictional tax legislation and assess income tax information that affects cash flow forecasts and capital allocation decisions. This ASU is effective for annual periods beginning after December 15, 2024, with early adoption permitted, and should be applied on a prospective basis although retrospective application is permitted. The Company is currently evaluating the impact this standard will have on its financial statement disclosures.
In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40). This ASU is intended to provide more detailed information about specified categories of expenses (including employee compensation, depreciation, and amortization) included in certain expense captions presented on the face of the income statement. This ASU is effective for fiscal years beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. This ASU may be applied either prospectively to financial statements issued for reporting periods after its effective date or retrospectively to all prior periods presented in the financial statements. The Company is currently assessing the impact this standard will have on its financial statement disclosures.
v3.25.0.1
Fair Value Measurements (Tables)
 12 Months Ended
Dec. 31, 2024
Fair Value Disclosures [Abstract]  
Schedule of Assets and Liabilities, Measured at Fair Value
The following table summarizes the Company’s financial assets (cash equivalents and marketable securities) at fair value as of December 31, 2024 (in thousands):
Fair Value as of December 31, 2024
Basis for Fair Value Measurements
(Level 1)(Level 2) (Level 3)
Assets:
Money market funds, included in cash and cash equivalents$13,349 $13,349 $— $— 
Fixed income mutual funds, included in short-term investments39,325 39,325 — — 
Total$52,674 $52,674 $— $— 
The following table summarizes the Company’s financial assets (cash equivalents and marketable securities) at fair value as of December 31, 2023 (in thousands):
Fair Value as of December 31, 2023
Basis for Fair Value Measurements
(Level 1)(Level 2) (Level 3)
Assets:
Money market funds, included in cash and cash equivalents$16,125 $16,125 $— $— 
Fixed income mutual funds, included in short-term investments48,396 48,396 — — 
Total$64,521 $64,521 $— $— 
v3.25.0.1
Balance Sheet Components (Tables)
 12 Months Ended
Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]  
Schedule of Inventory, Current
Inventories consist of the following (in thousands):
December 31,
2024
2023
Raw materials$4,248 $4,090 
Work-in-process1,778 627 
Finished goods7,355 6,497 
Total$13,381 $11,214 
Schedule of Property, Plant and Equipment
Property and equipment, net consists of the following (in thousands):
December 31,
2024
2023
Machinery, equipment, furniture and fixtures$4,659 $4,522 
Computer equipment and software1,932 1,822 
Leasehold improvements2,435 2,426 
9,026 8,770 
Less: Accumulated depreciation(7,974)(7,767)
Property and equipment, net $1,052 $1,003 
Schedule of Accrued Liabilities
Accrued liabilities consist of the following (in thousands):
December 31,
2024
2023
Payroll and related expenses $8,178 $9,655 
Inventory purchases575 588 
Professional fees50 30 
Other984 907 
$9,787 $11,180 
v3.25.0.1
Commitments and Contingencies (Tables)
 12 Months Ended
Dec. 31, 2024
Commitments and Contingencies Disclosure [Abstract]  
Schedule of Maturities of Operating Lease Liabilities
The maturities of operating lease liabilities as of December 31, 2024 are as follows (in thousands):
2025$2,942 
20263,031 
20273,122 
20283,215 
20293,312 
Thereafter1,704 
Total undiscounted lease payments17,326 
Less: imputed interest3,513 
Total operating lease liability13,813 
Less: current portion1,860 
Operating lease liability, net of current portion$11,953 
v3.25.0.1
Debt (Tables)
 12 Months Ended
Dec. 31, 2024
Debt Disclosure [Abstract]  
Schedule of Maturities of Long-term Debt
As of December 31, 2024, future minimum payments for the Term Loan are as follows (in thousands):
Term Loan
2025
$7,666 
2026
67,341 
Total75,007 
Less: Unamortized debt discount and issuance cost(392)
Less: Unaccreted backend fee(1,690)
Less: Interest(13,400)
Term Loan$59,525 
v3.25.0.1
Common Stock (Tables)
 12 Months Ended
Dec. 31, 2024
Equity [Abstract]  
Schedule of Stock by Class
As of December 31, 2024 and December 31, 2023, the Company had reserved common stock for future issuance as follows:
Year Ended December 31,
2024
2023
Outstanding options under the 2021 Plan1,987,784 2,208,341 
Shares available for future grant under the 2021 Plan2,201,012 1,314,502 
Outstanding options under the 2023 Inducement Plan380,424 380,424 
Outstanding restricted stock units under the 2021 Plan1,480,338 2,430,803 
Common stock available for ESPP475,416 399,798 
Total6,524,974 6,733,868 
v3.25.0.1
Stock Plans (Tables)
 12 Months Ended
Dec. 31, 2024
Share-Based Payment Arrangement [Abstract]  
Schedule of Available for Grant
A summary of shares available for grant under the 2021 Plan is as follows:
Shares Available for Grant
Shares available for grant as of January 1, 20231,443,946 
Authorized1,252,287 
Granted/Awarded(2,758,399)
Canceled1,322,669 
Withheld for taxes53,999 
Shares available for grant as of December 31, 2023
1,314,502 
Authorized1,391,173 
Granted/Awarded(1,157,793)
Canceled587,813 
Withheld for taxes65,317 
Shares available for grant as of December 31, 2024
2,201,012 
Schedule of Stock Option Activity
A summary of stock option activity for the years ended December 31, 2024 and 2023 is set forth below:
Options Outstanding
Number of SharesWeighted-Average Exercise PriceWeighted Average Remaining Contractual Term (in Years)
Balances as of January 1, 20233,446,583 $3.61 8.06
Granted695,225 $3.85 
Exercised(889,968)$0.17 
Canceled(663,075)$5.00 
Balances as of December 31, 2023
2,588,765 $4.51 7.17
Granted510,654 $12.04 
Exercised(556,718)$1.45 
Canceled(174,493)$15.89 
Balances as of December 31, 2024
2,368,208 $6.01 7.27
Vested and exercisable at December 31, 2024
1,568,345 $4.51 6.49
Vested and expected to vest at December 31, 2024
2,368,208 $6.01 7.27
Schedule of Employee Stock Purchase Plan
Compensation expense is calculated using the fair value of the employees' purchase rights under the Black-Scholes model, which was estimated using the following assumptions:
Year Ended December 31,
2024
2023
Expected term (in years)0.50.5
Expected volatility
76% - 78%
63% - 90%
Weighted average risk-free interest rate
4.34% - 5.40%
5.36% - 5.43%
Fair value of common stock
$6.47 - $10.95
$4.20 - $8.49
Dividend yield—%—%
Schedule of Restricted Stock Units
Activity with respect to restricted stock units, or RSUs, was as follows:
Number of Shares Underlying Outstanding Restricted Stock UnitsWeighted Average Grant Date Fair Value
Unvested, January 1, 20231,756,209 $10.15 
Granted2,063,174 $4.77 
Vested(728,986)$9.76 
Canceled(659,594)$7.14 
Unvested, December 31, 2023
2,430,803 $6.52 
Granted647,139 $13.00 
Vested(1,184,284)$6.65 
Canceled(413,320)$7.68 
Unvested, December 31, 2024
1,480,338 $8.92 
Schedule of Share-based Payment Arrangement, Expensed and Capitalized, Amount
The Company recognized stock-based compensation as follows (in thousands):
Year Ended December 31,
2024
2023
Cost of goods sold$723 $606 
Research and development3,270 2,749 
Selling, general and administrative6,289 6,203 
Total stock-based compensation$10,282 $9,558 
The above stock-based compensation expense related to the following equity-based awards (in thousands):
Year Ended December 31,
2024
2023
Stock options and restricted stock units$9,745 $9,271 
ESPP537 287 
Total stock-based compensation$10,282 $9,558 
Schedule of Employee Stock Options, Valuation Assumptions The fair value of employee stock options was estimated using the following assumptions for the years ended December 31, 2024 and December 31, 2023:
Year Ended December 31,
2024
2023
Expected term (in years)
5.27 - 6.25
5.27 - 6.25
Expected volatility
71% - 78%
60% - 63%
Weighted average risk-free interest rate
3.62% - 4.64%
3.74% - 3.94%
Fair value of common stock
$6.00 - $17.11
$1.54 - $4.50
Dividend yield—%—%
v3.25.0.1
Income Taxes (Tables)
 12 Months Ended
Dec. 31, 2024
Income Tax Disclosure [Abstract]  
Schedule of Effective Income Tax Rate Reconciliation
A reconciliation of the statutory U.S. federal rate to the Company’s effective tax rate is as follows:
December 31,
2024
2023
Tax at federal statutory rate21.0 %21.0 %
State taxes, net of federal benefit6.4 %4.5 %
Research and development tax credit5.1 %1.8 %
Stock-based compensation5.5 %(0.8)%
Nondeductible interest expense
(2.0)%(0.5)%
FIN 48 reserve(1.2)%(0.3)%
Change in valuation allowance(21.8)%(23.3)%
Federal net operating loss expiration(10.2)%— %
Other(2.8)%(2.4)%
Total — %— %
Schedule of Deferred Tax Assets and Liabilities
The tax effects of temporary differences that give rise to significant components of the deferred tax assets and liabilities are as follows (in thousands):
December 31,
2024
2023
Deferred tax assets:
Net operating loss carryforwards$42,043 $41,864 
Research and development credits14,903 13,069 
Research and development expenditures, capitalized for tax12,283 8,271 
Fixed assets and inventory28 151 
Accruals and reserves1,399 1,633 
Interest expense carryforward5,747 5,033 
Operating lease liability3,515 3,958 
Other1,281 1,718 
Gross deferred tax assets81,199 75,697 
Deferred tax liabilities:
Operating lease right-of-use asset(3,014)(3,436)
Total deferred tax liabilities(3,014)(3,436)
Valuation allowance(78,185)(72,261)
Net deferred tax assets$— $— 
Schedule of Unrecognized Tax Benefits Roll Forward
A reconciliation of the beginning and ending unrecognized tax benefit amount is as follows (in thousands):
Year Ended December 31,
2024
2023
Beginning balance$1,730 $1,601 
Increase in balance related to tax positions taken during the current year355 136 
Decrease in balance related to tax positions taken during prior years— (7)
Ending balance$2,085 $1,730 
v3.25.0.1
Net Loss per Share Attributable to Common Stockholders (Tables)
 12 Months Ended
Dec. 31, 2024
Earnings Per Share [Abstract]  
Schedule of Earnings Per Share, Basic and Diluted
The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders (in thousands, except for share and per share amounts):
Year Ended December 31,
2024
2023
Numerator:
Net loss attributable to common stockholders$(27,141)$(32,956)
Denominator:
Weighted-average common stock outstanding used to compute basic and diluted net loss per share29,126,314 25,851,813 
Net loss per share attributable to common stockholders, basic and diluted$(0.93)$(1.27)
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share
The following potentially dilutive securities outstanding have been excluded from the computation of diluted weighted average shares outstanding because such securities have an antidilutive impact due to the Company’s net loss, in common stock equivalent shares:
December 31,
2024
2023
Options to purchase common stock2,368,208 2,588,765 
Unvested restricted stock units1,480,338 2,430,803 
Shares committed under ESPP68,138 81,102 
Unvested early exercised common stock options— 30,211 
Total Shares3,916,684 5,130,881 
v3.25.0.1
Segment Information (Tables)
 12 Months Ended
Dec. 31, 2024
Segment Reporting [Abstract]  
Schedule of Segment Reporting Information, by Segment
The Company’s CODM is our Chief Executive Officer. Our CODM makes decisions on resource allocation, evaluates operating performance, and monitors budget versus actual results using net loss. In addition to the significant expense categories included within net loss presented on the Company’s Statements of Operations and Comprehensive Loss, disaggregated amounts that comprise selling, general and administrative expenses are as follows (in thousands):
Year Ended December 31,
2024
2023
Sales and marketing expense$39,669 $35,487 
General and administrative expense17,434 19,031 
Total selling, general and administrative expense$57,103 $54,518 
v3.25.0.1
The Company (Details) - USD ($)
$ in Thousands
 1 Months Ended 12 Months Ended
Nov. 30, 2022
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2025
Subsidiary, Sale of Stock [Line Items]        
Accumulated deficit   $ 530,950 $ 503,809  
Net cash used in operating activities   17,949 $ 19,701  
Cash, cash equivalents, and short-term investments   52,800    
Minimum annual net revenue   70,000    
Minimum cash and cash equivalents required after completion of IPO   $ 5,000    
Forecast        
Subsidiary, Sale of Stock [Line Items]        
Minimum cash and cash equivalents required after completion of IPO       $ 5,000
At-the-Market Equity Offering        
Subsidiary, Sale of Stock [Line Items]        
Proceeds from issuance of preferred stock, preference stock, and warrants $ 150,000      
Proceeds from issuance or sale by company of common stock $ 50,000      
Percentage of shares of common stock sold under sales agreement 3.00%      
Number of shares issued in transaction (in shares)   444,555 933,500  
Issuance of common stock   $ 3,400 $ 8,100  
Aggregate net proceeds   3,200 $ 7,600  
Amount remaining under ATM program   $ 38,500    
v3.25.0.1
Summary of Significant Accounting Policies (Details)
 1 Months Ended 12 Months Ended
Jul. 22, 2024
USD ($)
May 25, 2023
USD ($)
Jul. 30, 2022
USD ($)
Jun. 01, 2021
USD ($)
May 31, 2021
USD ($)
Dec. 31, 2024
USD ($)
segment
Dec. 31, 2023
USD ($)
Research and Development Arrangement, Contract to Perform for Others [Line Items]              
Revenue           $ 79,906,000 $ 65,421,000
Revenue recognized             1,100,000
Contract balances, account receivable           12,900,000 12,300,000
Deferred revenue           555,000 1,090,000
Remaining performance obligation           1,700,000  
Inventory write-downs           251,000 196,000
Impairment of long-lived assets           0 0
Issuance costs           212,000 509,000
Deferred offering costs           276,000 387,000
Grant period (in years)         5 years    
Research and development arrangement with federal government, total budget         $ 9,300,000    
Research and development arrangement with federal government, funding for subawards         $ 5,500,000    
Approved funding, first year       $ 800,000      
Approved funding, including subawards, first year       $ 400,000      
Approval for funding, year two $ 1,700,000 $ 3,000,000 $ 2,600,000        
Approval for funding, including subawards, year two $ 1,000,000 $ 1,500,000 $ 1,600,000        
Funding received for costs incurred           1,700,000 1,400,000
Prepaid expenses and other current assets           2,352,000 2,737,000
Advertising costs           $ 700,000 700,000
Number of operating segments | segment           1  
Number of reportable segments | segment           1  
At-the-Market Equity Offering              
Research and Development Arrangement, Contract to Perform for Others [Line Items]              
Issuance costs           $ 100,000 300,000
Non-Healthcare Organizations | Accounts Receivable | Customer Concentration Risk | UNITED STATES              
Research and Development Arrangement, Contract to Perform for Others [Line Items]              
Accounts receivable,with the exception of due           100,000  
Rapport              
Research and Development Arrangement, Contract to Perform for Others [Line Items]              
Revenue           $ 1,200,000 $ 400,000
Contractual support period           2 years  
Additional Funding Agreement Terms              
Research and Development Arrangement, Contract to Perform for Others [Line Items]              
Compensation earned           $ 3,800,000  
Prepaid expenses and other current assets           $ 100,000  
Minimum              
Research and Development Arrangement, Contract to Perform for Others [Line Items]              
Property, plant and equipment, useful life           3 years  
Maximum              
Research and Development Arrangement, Contract to Perform for Others [Line Items]              
Property, plant and equipment, useful life           5 years  
v3.25.0.1
Fair Value Measurements - Assets and Liabilities Measured at Fair Value (Details) - USD ($)
$ in Thousands
Dec. 31, 2024
Dec. 31, 2023
Assets:    
Money market funds, included in cash and cash equivalents $ 13,349 $ 16,125
Fixed income mutual funds, included in short-term investments 39,325 48,396
Total 52,674 64,521
(Level 1)    
Assets:    
Money market funds, included in cash and cash equivalents 13,349 16,125
Fixed income mutual funds, included in short-term investments 39,325 48,396
Total 52,674 64,521
(Level 2)    
Assets:    
Money market funds, included in cash and cash equivalents 0 0
Fixed income mutual funds, included in short-term investments 0 0
Total 0 0
(Level 3)    
Assets:    
Money market funds, included in cash and cash equivalents 0 0
Fixed income mutual funds, included in short-term investments 0 0
Total $ 0 $ 0
v3.25.0.1
Fair Value Measurements - Additional Information (Details) - USD ($)
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair value disclosure $ 0 $ 0
Unrealized gain 200,000 1,000,000.0
Cumulative unrealized gain $ 100,000  
Cumulative unrealized loss   100,000
Short-Term Investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cumulative unrealized loss   $ 1,100,000
v3.25.0.1
Balance Sheet Components - Inventory (Details) - USD ($)
$ in Thousands
Dec. 31, 2024
Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]    
Raw materials $ 4,248 $ 4,090
Work-in-process 1,778 627
Finished goods 7,355 6,497
Total $ 13,381 $ 11,214
v3.25.0.1
Balance Sheet Components - Property and Equipment (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Property, Plant and Equipment [Line Items]    
Property and equipment, gross $ 9,026 $ 8,770
Less: Accumulated depreciation (7,974) (7,767)
Property and equipment, net 1,052 1,003
Depreciation 207 172
Machinery, equipment, furniture and fixtures    
Property, Plant and Equipment [Line Items]    
Property and equipment, gross 4,659 4,522
Computer equipment and software    
Property, Plant and Equipment [Line Items]    
Property and equipment, gross 1,932 1,822
Leasehold improvements    
Property, Plant and Equipment [Line Items]    
Property and equipment, gross $ 2,435 $ 2,426
v3.25.0.1
Balance Sheet Components - Accrued Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2024
Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]    
Payroll and related expenses $ 8,178 $ 9,655
Inventory purchases 575 588
Professional fees 50 30
Other 984 907
Total accrued liabilities $ 9,787 $ 11,180
v3.25.0.1
Commitments and Contingencies - Additional Information (Details) - USD ($)
 1 Months Ended 12 Months Ended
Aug. 31, 2022
May 31, 2018
Dec. 31, 2024
Dec. 31, 2023
Jun. 30, 2021
May 31, 2019
Aug. 31, 2011
Loss Contingencies [Line Items]              
Renewal term 5 years            
Operating lease cost     $ 2,800,000 $ 2,800,000      
Operating lease term     5 years 6 months        
Operating lease percent     8.50%        
Operating lease, payments     $ 2,900,000 2,800,000      
Distribution agreement, initial term 3 years            
Distribution agreement, renewal term 1 year            
Distribution agreement intention to not renew 180 days            
Purchase obligation, to be paid in the next twelve months $ 2,400,000            
Percentage increase in purchase commitment 10.00%            
Purchase commitment, period 2 years            
Indemnification liability accrued for officers and directors     0 0      
Accrual for contingent liabilities     0 0      
Pending Litigation              
Loss Contingencies [Line Items]              
Accrual for contingent liabilities     $ 0 $ 0      
Minimum              
Loss Contingencies [Line Items]              
Annual rental payments   $ 2,800,000          
Maximum              
Loss Contingencies [Line Items]              
Annual rental payments   $ 3,300,000          
Lease Facility              
Loss Contingencies [Line Items]              
Face amount         $ 200,000 $ 700,000 $ 900,000
v3.25.0.1
Commitments and Contingencies - Operating Lease Maturity (Details) - USD ($)
$ in Thousands
Dec. 31, 2024
Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]    
2025 $ 2,942  
2026 3,031  
2027 3,122  
2028 3,215  
2029 3,312  
Thereafter 1,704  
Total undiscounted lease payments 17,326  
Less: imputed interest 3,513  
Total operating lease liability 13,813  
Less: current portion 1,860 $ 1,627
Operating lease liability, net of current portion $ 11,953 $ 13,814
v3.25.0.1
Debt - Additional Information (Details)
 1 Months Ended 12 Months Ended
May 31, 2024
Feb. 28, 2023
installment
Sep. 30, 2020
USD ($)
Dec. 31, 2024
USD ($)
Dec. 31, 2023
USD ($)
Mar. 01, 2023
Jan. 31, 2023
Dec. 31, 2022
Sep. 30, 2021
USD ($)
Sep. 24, 2020
USD ($)
shares
Debt Instrument [Line Items]                    
Principal payment number of installment | installment   1                
Term loan final maturity extension period 1 year                  
Minimum annual net revenue       $ 70,000,000.0            
Amortization of debt discount and issuance costs       $ 228,000 $ 283,000          
Term Loan                    
Debt Instrument [Line Items]                    
Face amount     $ 60,000,000.0              
Proceeds from long term debt     50,000,000.0              
Unused borrowing capacity     $ 10,000,000.0              
Interest rate     12.50%              
Effective percentage   12.50%   15.50%   13.50%        
Redemption fee, percent 10.00%                  
Minimum annual net revenue         45,000,000          
Backend fee       $ 1,690,000            
Amortization of debt discount and issuance costs       200,000 300,000          
Interest expense       8,800,000 $ 8,500,000          
Term Loan | Series B Redeemable Convertible Preferred Stock                    
Debt Instrument [Line Items]                    
Backend fee                 $ 1,000,000.0  
Warrants outstanding (in shares) | shares                   346,823
Warrant liability, noncurrent                   $ 600,000
Term Loan | Payment In Cash                    
Debt Instrument [Line Items]                    
Interest rate             8.50% 7.50%    
Term Loan | Payment in Kind (PIK) Note                    
Debt Instrument [Line Items]                    
Face amount       $ 6,000,000.0            
Interest rate             5.00% 5.00%    
Term Loan | Minimum                    
Debt Instrument [Line Items]                    
Effective percentage   15.70%                
Term Loan | Maximum                    
Debt Instrument [Line Items]                    
Effective percentage           16.80%        
v3.25.0.1
Debt - Maturities of Debt (Details) - Term Loan
$ in Thousands
Dec. 31, 2024
USD ($)
Debt Instrument [Line Items]  
2025 $ 7,666
2026 67,341
Total 75,007
Less: Unamortized debt discount and issuance cost (392)
Less: Unaccreted backend fee (1,690)
Less: Interest (13,400)
Term Loan $ 59,525
v3.25.0.1
Common Stock (Details) - $ / shares
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Class of Stock [Line Items]    
Common stock shares authorized (in shares) 200,000,000 200,000,000
Common stock par value (in dollars per share) $ 0.001 $ 0.001
Dividends declared cash (in dollars per share) $ 0 $ 0
Common stock reserved for future issuance (in shares) 6,524,974 6,733,868
Outstanding options under the 2021 Plan    
Class of Stock [Line Items]    
Common stock reserved for future issuance (in shares) 1,987,784 2,208,341
Shares available for future grant under the 2021 Plan    
Class of Stock [Line Items]    
Common stock reserved for future issuance (in shares) 2,201,012 1,314,502
Outstanding options under the 2023 Inducement Plan    
Class of Stock [Line Items]    
Common stock reserved for future issuance (in shares) 380,424 380,424
Outstanding restricted stock units under the 2021 Plan    
Class of Stock [Line Items]    
Common stock reserved for future issuance (in shares) 1,480,338 2,430,803
Common stock available for ESPP    
Class of Stock [Line Items]    
Common stock reserved for future issuance (in shares) 475,416 399,798
v3.25.0.1
Stock Plans - Additional Information (Details) - USD ($)
$ / shares in Units, $ in Millions
 1 Months Ended 6 Months Ended 12 Months Ended
Jan. 31, 2025
Jul. 31, 2023
Apr. 30, 2021
Apr. 20, 2021
Jun. 06, 2025
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Common stock reserved for future issuance (in shares)           6,524,974 6,733,868  
Options granted (in shares)           510,654 695,225  
Stock options exercised intrinsic value           $ 6.0 $ 5.3  
Options, subject to repurchase (in shares)           0 30,211  
ESPP discount percent     85.00%          
ESPP, length of offering period     6 months          
Unrecognized stock-based compensation expense           $ 15.0    
Period for recognition           2 years 1 month 6 days    
Minimum                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Vesting period (in years)     3 years          
Maximum                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Vesting period (in years)     4 years          
Stock option | Share-based Payment Arrangement, Employee                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Options vested fair value           $ 8.8 $ 7.8  
Options granted, weighted average grant date fair value (in dollars per share)           $ 8.13 $ 3.85  
2020 Stock Plan | Stock option                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Maximum term (in years)           10 years    
Minimum exercise price per share, percentage           110.00%    
2021 Equity Incentive Plan | Subsequent Event                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Shares authorized (in shares) 1,507,251              
2021 Equity Incentive Plan | Stock option                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Maximum term (in years)     5 years         10 years
Minimum exercise price per share, percentage       110.00%        
Common stock reserved for future issuance (in shares)       2,900,000        
Inducement Plan | Stock option                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Common stock reserved for future issuance (in shares)   380,424            
Inducement Plan | Stock option | Chief Executive Officer                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Options granted (in shares)   380,424            
2021 Employee Stock Purchase Plan                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Common stock reserved for future issuance (in shares)     580,000          
Shares authorized (in shares)     301,450          
Issuance of shares pursuant to Employee Stock Purchase Plan (in shares)           202,616 280,599  
Number of shares available for grant (in shares)           475,416    
Period for recognition           4 months 24 days    
Cost not yet recognized, amount           $ 0.2    
2021 Employee Stock Purchase Plan | Forecast                
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Offering period         6 months      
v3.25.0.1
Stock Plans - Available for Grant (Details) - 2021 Plan - shares
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Shares Available for Grant    
Shares available for grant, beginning balance (in shares) 1,314,502 1,443,946
Authorized (in shares) 1,391,173 1,252,287
Granted/Awarded (in shares) (1,157,793) (2,758,399)
Canceled (in shares) 587,813 1,322,669
Withheld for taxes (in shares) 65,317 53,999
Shares available for grant, ending balance (in shares) 2,201,012 1,314,502
v3.25.0.1
Stock Plans - Stock Option Activity (Details) - $ / shares
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Number of Shares      
Number of shares, beginning balance (in shares) 2,588,765 3,446,583  
Granted (in shares) 510,654 695,225  
Exercised (in shares) (556,718) (889,968)  
Canceled (in shares) (174,493) (663,075)  
Number of shares, ending balance (in shares) 2,368,208 2,588,765 3,446,583
Vested and exercisable (in shares) 1,568,345    
Vested and expected to vest (in shares) 2,368,208    
Weighted-Average Exercise Price      
Beginning balance (in dollars per share) $ 4.51 $ 3.61  
Granted (in dollar per share) 12.04 3.85  
Exercised (in dollar per share) 1.45 0.17  
Canceled (in dollar per share) 15.89 5.00  
Ending balance (in dollars per share) 6.01 $ 4.51 $ 3.61
Vested and exercisable (in dollars per share) 4.51    
Vested and expected to vest (in dollars per share) $ 6.01    
Weighted Average Remaining Contractual Term (in Years)      
Balance 7 years 3 months 7 days 7 years 2 months 1 day 8 years 21 days
Vested and exercisable 6 years 5 months 26 days    
Vested and expected to vest 7 years 3 months 7 days    
v3.25.0.1
Stock Plans - Employee Stock Options (Details) - $ / shares
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Stock option    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected volatility, minimum 71.00% 60.00%
Expected volatility, maximum 78.00% 63.00%
Weighted average risk-free interest rate, minimum 3.62% 3.74%
Weighted average risk-free interest rate, maximum 4.64% 3.94%
Dividend yield 0.00% 0.00%
Minimum | Stock option    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected term (in years) 5 years 3 months 7 days 5 years 3 months 7 days
Fair value of common stock (in dollars per share) $ 6.00 $ 1.54
Maximum | Stock option    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected term (in years) 6 years 3 months 6 years 3 months
Fair value of common stock (in dollars per share) $ 17.11 $ 4.50
2021 Employee Stock Purchase Plan    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected term (in years) 6 months 6 months
Expected volatility, minimum 76.00% 63.00%
Expected volatility, maximum 78.00% 90.00%
Weighted average risk-free interest rate, minimum 4.34% 5.36%
Weighted average risk-free interest rate, maximum 5.40% 5.43%
Dividend yield 0.00% 0.00%
2021 Employee Stock Purchase Plan | Minimum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Fair value of common stock (in dollars per share) $ 6.47 $ 4.20
2021 Employee Stock Purchase Plan | Maximum    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Fair value of common stock (in dollars per share) $ 10.95 $ 8.49
v3.25.0.1
Stock Plans - Restricted Stock Units (Details) - Unvested restricted stock units - $ / shares
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Number of Shares Underlying Outstanding Restricted Stock Units    
Unvested, beginning balance (in shares) 2,430,803 1,756,209
Granted (in shares) 647,139 2,063,174
Vested (in shares) (1,184,284) (728,986)
Canceled (in shares) (413,320) (659,594)
Unvested, ending balance (in shares) 1,480,338 2,430,803
Weighted Average Grant Date Fair Value    
Unvested, beginning balance (in dollars per share) $ 6.52 $ 10.15
Granted (in dollars per share) 13.00 4.77
Vested (in dollars per share) 6.65 9.76
Canceled (in dollars per share) 7.68 7.14
Unvested, ending balance (in dollars per share) $ 8.92 $ 6.52
v3.25.0.1
Stock Plans - Recognized Stock-based Compensation (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total stock-based compensation $ 10,282 $ 9,558
Stock options and restricted stock units    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total stock-based compensation 9,745 9,271
ESPP    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total stock-based compensation 537 287
Cost of goods sold    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total stock-based compensation 723 606
Research and development    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total stock-based compensation 3,270 2,749
Selling, general and administrative    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Total stock-based compensation $ 6,289 $ 6,203
v3.25.0.1
Income Taxes - Effective Income Tax Rate Reconciliation (Details)
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Income Tax Disclosure [Abstract]    
Tax at federal statutory rate 21.00% 21.00%
State taxes, net of federal benefit 6.40% 4.50%
Research and development tax credit 5.10% 1.80%
Stock-based compensation 5.50% (0.80%)
Nondeductible interest expense (2.00%) (0.50%)
FIN 48 reserve (1.20%) (0.30%)
Change in valuation allowance (21.80%) (23.30%)
Federal net operating loss expiration (10.20%) 0.00%
Other (2.80%) (2.40%)
Total 0.00% 0.00%
v3.25.0.1
Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2024
Dec. 31, 2023
Deferred tax assets:    
Net operating loss carryforwards $ 42,043 $ 41,864
Research and development credits 14,903 13,069
Research and development expenditures, capitalized for tax 12,283 8,271
Fixed assets and inventory 28 151
Accruals and reserves 1,399 1,633
Interest expense carryforward 5,747 5,033
Operating lease liability 3,515 3,958
Other 1,281 1,718
Gross deferred tax assets 81,199 75,697
Deferred tax liabilities:    
Operating lease right-of-use asset (3,014) (3,436)
Total deferred tax liabilities (3,014) (3,436)
Valuation allowance (78,185) (72,261)
Net deferred tax assets $ 0 $ 0
v3.25.0.1
Income Taxes - Additional Information (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Jan. 01, 2022
Operating Loss Carryforwards [Line Items]        
Deferred tax assets, deferred expense, capitalized research and development costs increase (decrease)       $ 12,300
Valuation allowance, deferred tax asset, increase (decrease), amount $ 5,900 $ 7,500    
Unrecognized tax benefits 2,085 1,730 $ 1,601  
Research Tax Credit Carryforward        
Operating Loss Carryforwards [Line Items]        
Tax credit carryforward 10,400      
Current Year        
Operating Loss Carryforwards [Line Items]        
Valuation allowance, deferred tax asset, increase (decrease), amount 5,500      
Valuation allowance, deferred tax liabilities, increase (decrease), amount 400      
Prior Year        
Operating Loss Carryforwards [Line Items]        
Valuation allowance, deferred tax asset, increase (decrease), amount   7,000    
Valuation allowance, deferred tax liabilities, increase (decrease), amount   $ 500    
Domestic Tax Jurisdiction        
Operating Loss Carryforwards [Line Items]        
Capitalized expenses, amortization period       5 years
Operating loss carryforwards 152,500      
Operating loss carryforwards, limitations on use 114,000      
Operating loss carryforwards amount permanently limited 226,800      
Unrecognized tax benefits 5,400      
Domestic Tax Jurisdiction | Research Tax Credit Carryforward        
Operating Loss Carryforwards [Line Items]        
Tax credit carryforward 5,400      
Foreign Tax Jurisdiction        
Operating Loss Carryforwards [Line Items]        
Capitalized expenses, amortization period       15 years
State and Local Jurisdiction        
Operating Loss Carryforwards [Line Items]        
Operating loss carryforwards 162,700      
Operating loss carryforwards amount permanently limited 150,700      
Unrecognized tax benefits 14,200      
State and Local Jurisdiction | Research Tax Credit Carryforward        
Operating Loss Carryforwards [Line Items]        
Tax credit carryforward $ 14,200      
v3.25.0.1
Income Taxes - Unrecognized Tax Benefits (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Unrecognized Tax Benefits [Roll Forward]    
Beginning balance $ 1,730 $ 1,601
Increase in balance related to tax positions taken during the current year 355 136
Decrease in balance related to tax positions taken during prior years 0 (7)
Ending balance $ 2,085 $ 1,730
v3.25.0.1
Net Loss per Share Attributable to Common Stockholders - Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($)
$ / shares in Units, $ in Thousands
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Numerator:    
Net loss attributable to common stockholders $ (27,141) $ (32,956)
Denominator:    
Weighted-average common stock outstanding used to compute basic net loss per share (in shares) 29,126,314 25,851,813
Weighted-average common stock outstanding used to compute diluted net loss per share (in shares) 29,126,314 25,851,813
Net loss per share attributable to common stockholders, basic (in dollars per share) $ (0.93) $ (1.27)
Net loss per share attributable to common stockholders, diluted (in dollars per share) $ (0.93) $ (1.27)
v3.25.0.1
Net Loss per Share Attributable to Common Stockholders - Schedule of Potentially Dilutive Securities Outstanding (Details) - shares
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Total shares (in shares) 3,916,684 5,130,881
Options to purchase common stock    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Total shares (in shares) 2,368,208 2,588,765
Unvested restricted stock units    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Total shares (in shares) 1,480,338 2,430,803
Shares committed under ESPP    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Total shares (in shares) 68,138 81,102
Unvested early exercised common stock options    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Total shares (in shares) 0 30,211
v3.25.0.1
Segment Information - Additional Information (Details)
$ in Thousands
 12 Months Ended
Dec. 31, 2024
USD ($)
segment
Dec. 31, 2023
USD ($)
Revenue, Major Customer [Line Items]    
Number of operating segments | segment 1  
Number of reportable segments | segment 1  
Revenue | $ $ 79,906 $ 65,421
Non-US    
Revenue, Major Customer [Line Items]    
Revenue | $ $ 200 $ 100
v3.25.0.1
Segment Information (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Segment Reporting Information [Line Items]    
Total selling, general and administrative expense $ 57,103 $ 54,518
Reportable Segments    
Segment Reporting Information [Line Items]    
Sales and marketing expense 39,669 35,487
General and administrative expense 17,434 19,031
Total selling, general and administrative expense $ 57,103 $ 54,518
v3.25.0.1
Subsequent Events (Details) - USD ($)
$ / shares in Units, $ in Millions
 1 Months Ended 12 Months Ended
Feb. 28, 2025
Dec. 31, 2024
Dec. 31, 2023
At-the-Market Equity Offering      
Subsequent Event [Line Items]      
Number of shares issued in transaction (in shares)   444,555 933,500
Subsequent Event      
Subsequent Event [Line Items]      
Shares repurchased, at cost $ 49.5    
Shares repurchases (in shares) 5,270,845    
Repurchase share price (in dollars per share) $ 9.40    
Subsequent Event | Follow-on Offering      
Subsequent Event [Line Items]      
Number of shares issued in transaction (in shares) 7,475,000    
Sale of stock (in dollars per share) $ 10.00    
Consideration received on transaction $ 69.8    
Subsequent Event | Over-Allotment Option      
Subsequent Event [Line Items]      
Number of shares issued in transaction (in shares) 975,000    
Subsequent Event | At-the-Market Equity Offering      
Subsequent Event [Line Items]      
Amount remaining under ATM program at termination $ 38.3