FORTE BIOSCIENCES, INC., 10-Q filed on 4/23/2020
Quarterly Report
v3.20.1
Document and Entity Information - shares
3 Months Ended
Mar. 31, 2020
Apr. 17, 2020
Cover [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Mar. 31, 2020  
Document Fiscal Year Focus 2020  
Document Fiscal Period Focus Q1  
Entity Interactive Data Current Yes  
Trading Symbol TOCA  
Entity Current Reporting Status Yes  
Entity Registrant Name Tocagen Inc  
Entity Central Index Key 0001419041  
Current Fiscal Year End Date --12-31  
Entity Filer Category Accelerated Filer  
Entity Shell Company false  
Entity Small Business true  
Entity Emerging Growth Company true  
Entity Ex Transition Period true  
Title of 12(b) Security Common Stock, par value $0.001 per share  
Security Exchange Name NASDAQ  
Entity File Number 001-38052  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 26-1243872  
Entity Address, Address Line One 4445 Eastgate Mall  
Entity Address, Address Line Two Suite 200  
Entity Address, City or Town San Diego  
Entity Address, State or Province CA  
Entity Address, Postal Zip Code 92121  
City Area Code 858  
Local Phone Number 412-8400  
Document Quarterly Report true  
Document Transition Report false  
Entity Common Stock, Shares Outstanding   23,914,723
v3.20.1
Condensed Balance Sheets (Unaudited) - USD ($)
Mar. 31, 2020
Dec. 31, 2019
Current assets:    
Cash and cash equivalents $ 14,232,000 $ 8,986,000
Marketable securities 0 12,835,000
Prepaid expenses and other current assets 277,000 1,135,000
Total current assets 14,509,000 22,956,000
Property and equipment, net 694,000 1,689,000
Operating lease right-of-use asset 3,429,000 3,515,000
Total assets 18,632,000 28,160,000
Current liabilities:    
Accounts payable 1,627,000 3,218,000
Accrued liabilities 6,030,000 5,242,000
Notes payable, current portion 4,981,000 4,744,000
Total current liabilities 12,638,000 13,204,000
Operating lease liability, net of current portion 3,912,000 4,027,000
Other long term liabilities   81,000
Total liabilities 16,550,000 17,312,000
Commitments and contingencies
Stockholders’ equity:    
Common stock, $0.001 par value; 200,000,000 shares authorized at March 31, 2020 and December 31, 2019; 23,914,723 and 23,899,261 shares issued and outstanding at March 31, 2020 and December 31, 2019, respectively 23,000 23,000
Additional paid-in capital 291,739,000 290,215,000
Accumulated deficit (289,680,000) (279,400,000)
Accumulated other comprehensive income   10,000
Total stockholders’ equity 2,082,000 10,848,000
Total liabilities and stockholders’ equity $ 18,632,000 $ 28,160,000
v3.20.1
Condensed Balance Sheets (Parenthetical) (Unaudited) - $ / shares
Mar. 31, 2020
Dec. 31, 2019
Statement Of Financial Position [Abstract]    
Common stock, par value $ 0.001 $ 0.001
Common stock, shares authorized 200,000,000 200,000,000
Common stock, shares issued 23,914,723 23,899,261
Common stock, shares outstanding 23,914,723 23,899,261
v3.20.1
Condensed Statements of Operations and Comprehensive Loss (Unaudited) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Income Statement [Abstract]    
License revenue   $ 9
Type of Revenue [Extensible List] us-gaap:LicenseMember us-gaap:LicenseMember
Operating expenses:    
Research and development $ 3,141 $ 12,434
General and administrative 5,556 4,446
Total operating expenses 8,697 16,880
Loss from operations (8,697) (16,871)
Other income (expense), net:    
Interest income 58 541
Interest expense (756) (754)
Loss on disposal of assets (885)  
Total other expense, net (1,583) (213)
Net loss (10,280) (17,084)
Other comprehensive income (loss):    
Net unrealized (loss) gain on investments (10) 41
Comprehensive loss $ (10,290) $ (17,043)
Net loss per common share, basic and diluted $ (0.43) $ (0.74)
Weighted-average number of common shares outstanding, basic and diluted 23,902,889 23,040,951
v3.20.1
Condensed Statements of Changes in Stockholders' Equity (Unaudited) - USD ($)
$ in Thousands
Total
Common Stock
Additional Paid-In Capital
Accumulated Deficit
Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2018 $ 58,145 $ 23 $ 274,029 $ (215,884) $ (23)
Beginning balance, shares at Dec. 31, 2018   23,000,151      
Exercise of stock options 248   248    
Exercise of stock options, shares   64,313      
Issuance of common stock, net of offering costs 1,504   1,504    
Issuance of common stock, net of offering costs, shares   146,398      
Stock-based compensation 2,000   2,000    
Other comprehensive income (loss) 41       41
Net loss (17,084)     (17,084)  
Ending balance at Mar. 31, 2019 44,854 $ 23 277,781 (232,968) 18
Ending balance, shares at Mar. 31, 2019   23,210,862      
Beginning balance at Dec. 31, 2019 10,848 $ 23 290,215 (279,400) 10
Beginning balance, shares at Dec. 31, 2019   23,899,261      
Exercise of stock options 10   10    
Exercise of stock options, shares   15,462      
Stock-based compensation 1,514   1,514    
Other comprehensive income (loss) (10)       $ (10)
Net loss (10,280)     (10,280)  
Ending balance at Mar. 31, 2020 $ 2,082 $ 23 $ 291,739 $ (289,680)  
Ending balance, shares at Mar. 31, 2020   23,914,723      
v3.20.1
Condensed Statements of Cash Flows - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
OPERATING ACTIVITIES    
Net loss $ (10,280) $ (17,084)
Adjustments to reconcile net loss to net cash used in operating activities:    
Stock-based compensation 1,514 2,000
Depreciation 57 216
Loss on disposal of property and equipment 916  
Noncash interest expense 654 142
Accretion of discount on investments, net 103 (41)
Changes in operating assets and liabilities:    
Prepaid expenses and other assets 877 110
Accounts payable (1,591) (490)
Accrued liabilities 353 (2,777)
Deferred license revenue   (9)
Other 328 251
Net cash used in operating activities (7,069) (17,682)
INVESTING ACTIVITIES    
Proceeds from the sale/maturity of marketable securities 12,722 27,836
Purchases of marketable securities   (21,606)
Purchases of property and equipment   (133)
Net cash provided by investing activities 12,722 6,097
FINANCING ACTIVITIES    
Principal payments on notes payable (417)  
Proceeds from issuance of common stock 10 248
Proceeds from issuance of common stock under the ATM facility, net of issuance cost   1,522
Net cash (used in) provided by financing activities (407) 1,770
Net increase (decrease) in cash and cash equivalents 5,246 (9,815)
Cash and cash equivalents, beginning of period 8,986 40,813
Cash and cash equivalents, end of period 14,232 30,998
NONCASH INVESTING AND FINANCING ACTIVITIES    
Cash paid for interest $ 101 606
Property and equipment purchases included in accounts payable and accrued liabilities   $ 26
v3.20.1
Organization and Basis of Presentation
3 Months Ended
Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]  
Organization and Basis of Presentation

1.

Organization and Basis of Presentation

Historically, Tocagen Inc. (Tocagen or the Company) was a clinical-stage, cancer-selective gene therapy company developing broadly-applicable product candidates designed to activate a patient’s immune system against their own cancer. The Company’s cancer-selective gene therapy platform is built on retroviral replicating vectors which are designed to selectively deliver therapeutic genes into the DNA of cancer cells. The Company’s gene therapy approach is designed to fight cancer through immunotherapeutic mechanisms of action without the autoimmune toxicities commonly experienced with other immunotherapies. The Company views its operations and manages its business in one operating segment.

Since the Company’s inception in August 2007, it has devoted substantially all of its efforts to developing its gene therapy platform and its lead product candidate, Toca 511 & Toca FC. The Company has never been profitable and has incurred significant operating losses in each year since its inception. The Company has not generated revenues from its principal operations.

The accompanying unaudited condensed financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information and the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, these financial statements do not include all of the information and footnotes required by GAAP for complete financial statements. In management’s opinion, the accompanying financial statements reflect all adjustments, consisting of normal recurring adjustments, considered necessary for a fair presentation of the results for the interim periods presented. Interim financial results are not necessarily indicative of results anticipated for the full year. These unaudited condensed financial statements should be read in conjunction with the audited financial statements and footnotes included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2019, from which the balance sheet information herein was derived.

Liquidity

On February 19, 2020, the Company, Telluride Merger Sub, Inc., a Delaware corporation and wholly owned subsidiary of the Company (Merger Sub), and Forte Biosciences, Inc. (Forte) entered into an Agreement and Plan of Merger and Reorganization (the Merger Agreement). Upon the terms and subject to the satisfaction of the conditions described in the Merger Agreement, including approval of the transaction by the Company’s stockholders, Merger Sub will be merged with and into Forte, with Forte surviving as a wholly-owned subsidiary of the Company (the Merger).

The accompanying financial statements have been prepared on a basis which assumes the Company is a going concern, and do not include any adjustments to reflect the possible future effects on the recoverability and classification of assets or the amounts and classifications of liabilities that may result from any uncertainty related to the Company’s ability to continue as a going concern. The Company has experienced net losses and negative cash flows from operating activities since its inception. As of March 31, 2020, the Company had cash and cash equivalents of $14.2 million and accumulated deficit of $289.7 million.  

 

Based on the Company’s operating plans, its cash and cash equivalents may not be sufficient to fund operations for the next 12 months. As a result, there is substantial doubt about the Company’s ability to continue as a going concern.

To conserve our cash resources, the Company has substantially reduced its workforce and has wound down and suspended its research and development activities. The Company is continuing to provide study drug for patients who remain on therapy via investigator sponsored trials (principal investigator assumes responsibility) through single patient investigational new drug applications and is continuing its day-to-day business operations including the limited remaining activities required to wrap up the Toca 5 trial.

Use of Estimates

The Company’s financial statements are prepared in accordance with GAAP, which requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses and the disclosure of contingent assets and liabilities in the financial statements and accompanying notes. Significant estimates in the Company’s financial statements relate to clinical trial accruals and the valuation of equity awards. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Actual results may differ from these estimates under different assumptions or conditions.

v3.20.1
Summary of Significant Accounting Policies
3 Months Ended
Mar. 31, 2020
Accounting Policies [Abstract]  
Summary of Significant Accounting Policies

2.

Summary of Significant Accounting Policies  

Clinical Trial Accruals

Expenses related to clinical studies are based on estimates of the services received and efforts expended pursuant to the Company’s contract arrangements. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. There may be instances in which payments made to the Company’s service providers will temporarily exceed the level of services provided and result in a prepayment of the clinical expense. Payments under some of these contracts depend on factors such as the successful enrollment of patients, site initiation and the completion of clinical milestones. The Company makes estimates of its accrued expenses as of each balance sheet date in its financial statements based on facts and circumstances known at that time. In accruing service fees, the Company estimates the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from its estimate, the Company adjusts the accrual or prepaid expense balance accordingly. Historically, the Company’s estimated accrued liabilities have materially approximated actual expense incurred.

Revenue Recognition

Revenue generally consists of license revenue with upfront payments and development milestones considered probable of achievement.

Revenue is recognized when control of the promised goods or services is transferred to the Company’s customers in an amount that reflects the consideration the Company expects to receive from its customers in exchange for those goods and services. This process involves identifying the contract with a customer, determining the performance obligations in the contract, determining the transaction price, allocating the contract price to the distinct performance obligations in the contract, and recognizing revenue when or as the Company satisfies the performance obligation(s).

At contract inception, the Company assesses the goods and services promised within each contract and assesses whether each promised good or service is distinct and determines that those are performance obligations. A performance obligation is considered distinct from other obligations in a contract when it provides a benefit to the customer either on its own or together with other resources that are readily available to the customer and is separately identified in the contract. The Company considers factors such as the research, manufacturing and commercialization capabilities of the collaboration partner and the availability of the associated expertise in the general marketplace. The Company considers a performance obligation satisfied once the Company has transferred control of a good or service to the customer, meaning the customer has the ability to use and obtain the benefit of the good or service. The Company recognizes revenue for satisfied performance obligations only when the Company determines there are no uncertainties regarding payment terms or transfer of control.

Collaborative Arrangements

The Company enters into collaborative arrangements with partners that may include payment to the Company of one or more of the following: (i) license fees; (ii) payments related to the achievement of developmental, regulatory, or commercial milestones; and (iii) royalties on net sales of licensed products.  Where a portion of non‑refundable upfront fees or other payments received are allocated to continuing performance obligations under the terms of a collaborative arrangement, they are recorded as contract liabilities and recognized as revenue when (or as) the underlying performance obligation is satisfied.  

As part of the accounting for these arrangements, the Company must develop estimates and assumptions that require judgment to determine the underlying stand-alone selling price for each performance obligation which determines how the transaction price is allocated among the performance obligation(s). The stand-alone selling price may include items such as forecasted revenues, development timelines, discount rates, and probabilities of technical and regulatory success. The Company evaluates each performance obligation to determine if it can be satisfied at a point in time or over time. In addition, variable consideration must be evaluated to determine if it is constrained and, therefore, excluded from the transaction price.

License Fees

If a license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company recognizes revenues from non-refundable, upfront fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license, collaboration or other revenues and earnings in the period of adjustment.

Milestone Payments

At the inception of each arrangement that includes milestone payments (variable consideration), the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price. If it is probable that a milestone event would occur at the inception of the arrangement, the associated milestone value is included in the transaction price. Milestone payments that are not within the Company’s control, such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received. The transaction price is then allocated to each performance obligation on a relative stand-alone selling price basis, for which the Company recognizes revenue as or when the performance obligations under the contract are satisfied. At the end of each reporting period, the Company evaluates the probability of achievement of such milestones and any related constraint(s), and if necessary, may adjust the Company’s estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license, collaboration or other revenues and earnings in the period of adjustment.

Royalties

For arrangements that include sales-based royalties, including milestone payments based on the level of sales, and for which the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). To date, the Company has not recognized any royalty revenue resulting from its collaborative arrangements.

Stock-Based Compensation

Stock-based compensation expense represents the cost of the grant date fair value of stock awards, including stock options, and stock purchase rights granted to employees and members of the Company’s board of directors. For awards with time-based vesting provisions, the Company estimates the fair value of stock options on the date of grant using the Black-Scholes option pricing model and recognizes the expense over the requisite service period of the awards, which is generally the vesting period, on a straight-line basis. For awards with performance-based vesting provisions, the Company estimates the fair value of stock option grants on the date of grant, or the date when all of the terms of the grant have been agreed to, if later, and recognizes the expense based on the probability of the occurrence of the individual milestones at each reporting period. The expense is recognized over the implicit service period that commences once management believes the performance criteria are probable of being met.  For purchase rights, the Company estimates the fair value of the purchase as of the plan enrollment date and recognizes expense on a straight-line basis over the applicable offering period.  The Company accounts for forfeitures when they occur and reverses any compensation cost previously recognized for awards for which the requisite service has not been completed, in the period that the award is forfeited.

Net Loss Per Share

Basic and diluted net loss per common share for the periods presented is computed by dividing net loss by the weighted-average number of common shares outstanding during the respective periods, without consideration of common stock equivalents as they are anti-dilutive. Common stock equivalents that could potentially dilute earnings in the future are comprised of options to purchase shares of common stock outstanding under the Company’s equity incentive plan and warrants for the purchase of shares of common stock. For all periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding due to the Company’s net loss position.

Common stock equivalents from potentially dilutive securities that are not included in the calculation of diluted net loss per share, because to do so would be anti-dilutive, are as follows:

 

 

 

Three Months Ended

March 31,

 

 

 

2020

 

 

2019

 

Common stock options and awards

 

 

4,798,269

 

 

 

4,262,170

 

Common stock warrants

 

 

66,514

 

 

 

67,238

 

Total

 

 

4,864,783

 

 

 

4,329,408

 

 

Recently Issued Accounting Pronouncements

The Company has evaluated all recent accounting pronouncements issued by the Financial Accounting Standards Board in the form of Accounting Standards Updates through the date these financial statements were available to be issued and found no recent accounting pronouncements issued, but not yet effective that when adopted, would have a material impact on the financial statements of the Company.

v3.20.1
Fair Value of Financial Instruments
3 Months Ended
Mar. 31, 2020
Fair Value Disclosures [Abstract]  
Fair Value of Financial Instruments

3.

Fair Value of Financial Instruments

Fair Values of Assets Measured on a Recurring Basis

The Company did not have any fair value measurements on a recurring basis as of March 31, 2020. The following table summarizes the Company’s assets that required fair value measurements on a recurring basis as of December 31, 2019 and their respective input levels based on the fair value hierarchy (in thousands):

 

 

 

 

 

 

 

Fair Value Measurements at End of Period Using:

 

 

 

Total

 

 

Quoted Market

Prices for

Identical Assets

(Level 1)

 

 

Significant

Other

Observable

Inputs

(Level 2)

 

 

Significant

Unobservable

Inputs

(Level 3)

 

December 31, 2019

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Marketable securities:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Corporate debt securities

 

$

3,700

 

 

$

 

 

$

3,700

 

 

$

 

Commercial paper

 

 

5,485

 

 

 

 

 

 

5,485

 

 

 

 

Asset-backed securities

 

 

3,650

 

 

 

 

 

 

3,650

 

 

 

 

 

 

$

12,835

 

 

$

 

 

$

12,835

 

 

$

 

 

Marketable Securities. When there are fair values determined by Level 1 inputs, which utilize quoted prices in active markets for identical assets, the level of judgment required to estimate fair value is relatively low.

Fair values determined by Level 2 inputs, which utilize data points that are observable such as quoted prices, interest rates and yield curves, require the exercise of judgment and use of estimates, that if changed, could significantly affect the Company’s financial position and results of operations. Investments in corporate debt securities, commercial paper and asset-backed securities are valued using Level 2 inputs. Level 2 securities are initially valued at the transaction price and subsequently valued and reported utilizing inputs other than quoted prices that are observable either directly or indirectly, such as quotes from third-party pricing vendors.

There were no transfers in or out of Level 1 or Level 2 investments during the three months ended March 31, 2020 or 2019.

At March 31, 2020 and December 31, 2019, the Company had investments in money market funds of $4.2 million and $6.3 million, respectively, that were measured at fair value using the net asset value per share (or its equivalent) that have not been classified in the fair value hierarchy. The funds were invested primarily in U.S. government securities.

Fair Values of Other Financial Instruments

The carrying amounts of certain of the Company’s financial instruments, including accounts payable, approximate fair value due to their short-term nature. The Company’s notes payable recorded on the balance sheet as of March 31, 2020 of $5.0 million were recorded at fair value as the notes payable were paid off in full on April 10, 2020.

v3.20.1
Certain Financial Statement Caption Information
3 Months Ended
Mar. 31, 2020
Balance Sheet Related Disclosures [Abstract]  
Certain Financial Statement Caption Information

4.

Certain Financial Statement Caption Information

Marketable Securities

The Company did not have marketable securities as of March 31, 2020. The following is a summary of the Company’s marketable securities as of December 31, 2019 (in thousands):

 

 

 

Maturity

(in years)

 

Amortized Cost

 

 

Unrealized Gain

 

 

Unrealized Loss

 

 

Fair Value

 

December 31, 2019

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Corporate debt securities

 

1 or less

 

$

2,699

 

 

$

1

 

 

$

 

 

$

2,700

 

Corporate debt securities

 

>1 and <5

 

 

999

 

 

 

1

 

 

 

 

 

 

1,000

 

Commercial paper

 

1 or less

 

 

5,481

 

 

 

4

 

 

 

 

 

 

5,485

 

Asset-backed securities

 

1 or less

 

 

3,646

 

 

 

4

 

 

 

 

 

 

3,650

 

 

 

 

 

$

12,825

 

 

$

10

 

 

$

-

 

 

$

12,835

 

 

The Company classified all of its available-for-sale investment securities at December 31, 2019, including those with maturity greater than one year, as current assets on the balance sheet based on the highly liquid nature of these investment securities and because these investment securities were considered available for use in current operations.

There were no impairments considered other-than-temporary during the periods presented, as it is management’s intention and ability to hold the securities until a recovery of the cost basis or recovery of fair value. Gross realized gains and losses on sales of marketable securities were immaterial for all periods presented.

Accrued Liabilities

Accrued liabilities are comprised of (in thousands):

 

 

 

March 31,

2020

 

 

December 31,

2019

 

Clinical trial expenses

 

$

405

 

 

$

2,404

 

Payroll and other employee-related expenses

 

 

4,106

 

 

 

1,116

 

Contract manufacturing services

 

 

329

 

 

 

387

 

Current lease liability

 

 

435

 

 

 

416

 

Professional fees

 

 

377

 

 

 

330

 

Interest payable

 

 

34

 

 

 

37

 

Other

 

 

344

 

 

 

552

 

Total accrued liabilities

 

$

6,030

 

 

$

5,242

 

 

The Company further reduced its workforce in the first quarter 2020 as a result of the proposed Merger and incurred personnel-related restructuring charges of approximately $3.5 million for employee severance and other related termination benefits. As of March 31, 2020, $3.3 million of severance and other related termination costs were included in accrued liabilities on the balance sheet.

v3.20.1
Notes Payable
3 Months Ended
Mar. 31, 2020
Debt Disclosure [Abstract]  
Notes Payable

5.

Notes Payable

Loan Agreement

On October 30, 2015, the Company entered into a Loan and Security Agreement (2015 Loan Agreement) with two lenders whereby it borrowed $18.0 million (the Initial Loans). Balances under the 2015 Loan Agreement were due in monthly principal and interest payments, with final maturity of the Initial Loans in May 2019. Each Initial Loan included a final payment fee of 7.95% of the original principal amount due upon maturity.

On May 18, 2018, the Company entered into an Amended and Restated Loan and Security Agreement, which was further amended in August 2018 and October 2019 (2018 Loan Agreement), pursuant to which the lenders agreed to lend the Company $26.5 million as term loans (the Term Loans). Of the total proceeds, $8.6 million was applied to the repayment of outstanding principal, interest and final payment owed pursuant to the Initial Loans.

The Company evaluated the 2018 Loan Agreement in accordance with ASC Topic 470, which requires assessment of whether the modification is considered a substantial modification, in which case the modification would be accounted for as a debt extinguishment. Based on the Company’s evaluation, the 2018 Loan Agreement was considered substantial and therefore the unamortized discount associated with the 2015 Loan Agreement was written off through interest expense and the principal balance of the 2015 Loan Agreement was written off.    

The Term Loans would have matured on December 1, 2022 (the Maturity Date) and bore interest at a floating per annum rate equal to the greater of (i) 8.50% and (ii) the sum of (a) the prime rate reported in the Wall Street Journal on the last business day of the month that immediately proceeds the month in which the interest will accrue, plus (b) 3.75%. The interest rate as of March 31, 2020 was 8.50%. The Company was required to make a final payment of 7.95% of the principal amount of the Term Loans payable on the earlier of (i) the Maturity Date, (ii) the acceleration of any Term Loans, or (iii) the prepayment of the Term Loans. On October 31, 2019, the Company entered into a Consent and Second Amendment to the Amended and Restated Loan and Security Agreement (the Second Amendment) and made a prepayment of $23.3 million, which amount was used to prepay i) a portion equal to $21.5 million of the outstanding principal of the Term Loans plus all accrued and unpaid interest thereon through the prepayment date, ii) prorated portion of the final payment with respect to the portion of such Term Loans being prepaid, plus iii) all outstanding lenders’ expenses as of the date of the Second Amendment.

In connection with the Second Amendment, the lenders (i) agreed to waive any prepayment fee otherwise applicable to a prepayment of the Term Loans on or after the date of the Second Amendment, (ii) consent to the sale of certain specified equipment, so long as the net cash proceeds from the sale of such assets are used to repay the Term Loans, and (iii) release their lien on the specified equipment upon the closing of any such sale. Under the Second Amendment, the Company also agreed to grant a security interest in the Company’s intellectual property as additional collateral to secure the Term Loans for the ratable benefit of the lenders.

On April 10, 2020, the Company made a prepayment of $4.9 million under the 2018 Loan Agreement, which amount was used to prepay i) the remaining outstanding principal of the Term Loans of $4.4 million, plus all accrued and unpaid interest thereon, ii) the remaining final payment with respect to the Term Loans and iii) all outstanding lenders’ expenses as of the date of the Second Amendment. In connection with the Company’s payment, the 2018 Loan Agreement was terminated and the lenders consented to the release of all liens under the 2018 Loan Agreement on the Company’s assets, including intellectual property. As a result of the prepayment, all amounts due under the Term Loans have been classified as a current liability on the balance sheet as of March 31, 2020.

The 2018 Loan Agreement contained customary conditions of borrowing, events of default and covenants, including covenants that restricted the Company’s ability to dispose of assets, merge with or acquire other entities, incur indebtedness and make distributions to holders of the Company’s capital stock. If an event of default would have occurred, including the occurrence of a material adverse change, the Company would have been liable for immediate repayment of all obligations under the 2018 Loan Agreement. As of March 31, 2020, the balance sheet was adjusted for the amount due under the Term Loans for the outstanding principal, plus all accrued and unpaid interest thereon, and the final payment. All unaccreted balances for the final payment and unamortized discounts were adjusted through interest expense.     

In conjunction with the 2018 Loan Agreement, the Company issued the lenders warrants exercisable for 56,578 shares of common stock (the Warrants). The Warrants are exercisable in whole or in part, immediately, and have a per share exercise price of $9.35. The Warrants will terminate on the earlier of May 18, 2028 or the closing of a certain merger or consolidation transaction. The Company recorded the Warrants as a debt discount, which is a contra-liability against debt, and was amortizing the balance over the life of the underlying debt. The offset to the contra-liability is recorded as additional paid in capital in the Company’s balance sheet as the Warrants were determined to be an equity instrument. The Company determined the fair value of the Warrants at the date of issuance was $0.5 million using the Black-Scholes option pricing model based on significant unobservable inputs (Level 3) with an expected term of 10 years, volatility of 85.6%, risk free rate of 3.1% and expected dividend of 0%.  

The aggregate carrying amounts of the Term Loans are comprised of the following (in thousands):

 

 

 

March 31,

2020

 

 

December 31,

2019

 

Principal

 

$

4,583

 

 

$

5,000

 

Add: accreted liability for final payment fee

 

 

398

 

 

 

138

 

Less: unamortized discount

 

 

 

 

 

(394

)

 

 

$

4,981

 

 

$

4,744

 

 

v3.20.1
Stockholders' Equity
3 Months Ended
Mar. 31, 2020
Equity [Abstract]  
Stockholders' Equity

6.

Stockholders’ Equity

The Company did not sell any shares under its Equity Distribution Agreement with Citigroup Global Markets Inc. (the Sales Agreement) during the three months ended March 31, 2020. During the three months ended March 31, 2019, the Company sold 146,398 shares of its common stock under the Sales Agreement. The sales were made at a weighted average price of $10.69 per share resulting in net proceeds of $1.5 million. As of March 31, 2020, the Company has sold 760,089 shares of common stock and has received net proceeds of $7.7 million under the Sales Agreement.

Common Stock Reserved for Future Issuance

Common stock reserved for future issuance as of March 31, 2020 is as follows:

 

Issued and Outstanding:

 

 

 

 

Stock options and awards

 

 

4,798,269

 

Warrants for common stock

 

 

66,514

 

Shares reserved for issuance under the 2017 Employee Stock

   Purchase Plan

 

 

725,847

 

Shares reserved for future award grants

 

 

1,020,458

 

Total

 

 

6,611,088

 

 

The following table summarizes the allocation of the Company’s non-cash stock-based compensation expense for all stock awards during the three months ended March 31, 2020 and 2019 (in thousands): 

 

 

 

Three Months Ended

March 31,

 

 

 

2020

 

 

2019

 

Research and development

 

$

364

 

 

$

746

 

General and administrative

 

 

1,150

 

 

 

1,254

 

Total

 

$

1,514

 

 

$

2,000

 

 

The Company has not recognized non-cash stock-based compensation expense for outstanding options to purchase 188,651 shares of common stock with performance-based vesting provisions after its evaluation that the occurrence of the individual milestones is not probable as of March 31, 2020.

v3.20.1
Collaborative Arrangements
3 Months Ended
Mar. 31, 2020
Collaborative Arrangements [Abstract]  
Collaborative Arrangement

7.

Collaborative Arrangements

ApolloBio License

On April 18, 2018, the Company entered into a License Agreement (the License Agreement) with Beijing Apollo Venus Biomedical Technology Limited and ApolloBio Corp. (collectively, ApolloBio), which became effective in July 2018, pursuant to which the Company granted to ApolloBio an exclusive license to develop and commercialize Toca 511 & Toca FC within the greater China region, including mainland China, Hong Kong, Macao and Taiwan (the Licensed Territory).

The Company is eligible to receive up to an aggregate $111.0 million, less withholding and other taxes, upon the achievement of specified development and commercial milestones.  The Company completed its planned enrollment of 380 patients in the Toca 5 clinical trial in 2018 and earned a $2.0 million development milestone payment. The Company is also eligible for low double-digit tiered royalty payments based on annual net sales of licensed products in the Licensed Territory, subject to reduction under specified circumstances. ApolloBio will be responsible for all development and commercialization costs in the Licensed Territory. Future payments by ApolloBio are subject to the People’s Republic of China (PRC) currency exchange approval and may be subject to other approvals by PRC authorities.

Under the License Agreement, the Company has received net proceeds of $15.2 million which is comprised of a $16.0 million up-front payment and a $2.0 million development milestone payment less $1.7 million in foreign income taxes and $1.1 million in certain foreign non-income taxes.

Unless earlier terminated, the License Agreement will expire upon the expiration of the last-to-expire royalty term for any and all licensed products, which royalty term is, with respect to a licensed product in a particular region (i.e., mainland China, Hong Kong, Macao and Taiwan) of the Licensed Territory (each, a Region), the latest of (i) 10 years after the first commercial sale of such licensed product in such Region, (ii) the expiration of all regulatory exclusivity as to such licensed product in such Region and (iii) the date of expiration of the last valid patent claim covering such licensed product in such Region. Either party may terminate the License Agreement upon a material breach by the other party that remains uncured following 60 days (or, with respect to any payment breach, 10 days) after the date of written notice of such breach. ApolloBio may terminate the License Agreement at any time by providing 90 days’ prior written notice to the Company. In addition, the Company may terminate the License Agreement upon written notice to ApolloBio under specified circumstances if ApolloBio challenges the licensed patent rights.

Under ASU 2014-09, Revenue from Contracts with Customers (Topic 606), the Company evaluated the terms of the License Agreement and the transfer of intellectual property rights (the license) was identified as the only performance obligation as of the inception of the License Agreement. The Company determined that the transaction price under the License Agreement was comprised solely of the $16.0 million upfront payment. The future potential development and commercial milestone payments were not included in the transaction price as they were determined to be fully constrained. As part of the evaluation of the development and commercial milestone constraint, the Company determined that the achievement of such milestones is contingent upon success in future clinical trials and regulatory approvals, each of which was uncertain at the inception of the License Agreement. The Company will re-evaluate the transaction price each quarter or as uncertain events are resolved or other changes in circumstances occur. Future potential development and commercial milestone amounts would be recognized as revenue, if unconstrained. Any reimbursable program costs are recognized proportionately with the performance of the underlying services and are accounted for as a reduction to research and development expense and are excluded from the transaction price.

The entire $16.0 million transaction price was allocated to the license performance obligation. The license was delivered in connection with the execution of the License Agreement and the performance obligation was fully satisfied in 2018 (transfer of intellectual property). Additionally, the Company earned a $2.0 million development milestone payment in 2018 upon completion of the planned enrollment of 380 patients in the Toca 5 clinical trial.

v3.20.1
Commitments
3 Months Ended
Mar. 31, 2020
Commitments And Contingencies Disclosure [Abstract]  
Commitments

8.

Commitments

The Company leases its office and laboratory space located in San Diego, California, for its corporate headquarters and research facility under an operating lease agreement (the Lease). The Lease commenced in March 2018. The term of the Lease is eight years and the Company has one option to extend the Lease for a period of five additional years.

In connection with the inception of the Lease, the Company was provided and fully utilized a tenant improvement allowance of $1.2 million. The Lease provides for an abatement of a portion of the lease payments for the first nine months of the lease term and includes escalation clauses in the future.

On December 16, 2019, the Company entered into a First Amendment (the “Lease Amendment”) to the Lease. Under the terms of the Lease Amendment, the termination date of a portion of the premises containing approximately 21,180 rentable square feet was accelerated from June 30, 2026 to December 31, 2019. The Lease Amendment eliminated further rents due for the terminated rentable square feet, including aggregate base rent over the remaining term of approximately $7.6 million.

v3.20.1
Subsequent Events
3 Months Ended
Mar. 31, 2020
Subsequent Events [Abstract]  
Subsequent Events

9.

Subsequent Events

On April 17, 2020, the Company entered into an Asset Purchase Agreement with Denovo BioPharma LLC (Denovo) pursuant to which, among other things, Denovo agreed to acquire from the Company certain intellectual property rights, materials, know-how, and data, including those related to the Company’s retroviral replicating vector technologies, including Toca 511 & Toca FC for a purchase price of $1.1 million. Under the terms of the Asset Purchase Agreement, the transaction will close upon the earlier of (a) immediately after the closing of the Merger and (b) promptly after the termination of the Merger Agreement.

v3.20.1
Summary of Significant Accounting Policies (Policies)
3 Months Ended
Mar. 31, 2020
Accounting Policies [Abstract]  
Use of Estimates

Use of Estimates

The Company’s financial statements are prepared in accordance with GAAP, which requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses and the disclosure of contingent assets and liabilities in the financial statements and accompanying notes. Significant estimates in the Company’s financial statements relate to clinical trial accruals and the valuation of equity awards. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Actual results may differ from these estimates under different assumptions or conditions.

Clinical Trial Accruals

Clinical Trial Accruals

Expenses related to clinical studies are based on estimates of the services received and efforts expended pursuant to the Company’s contract arrangements. The financial terms of these agreements are subject to negotiation, vary from contract to contract and may result in uneven payment flows. There may be instances in which payments made to the Company’s service providers will temporarily exceed the level of services provided and result in a prepayment of the clinical expense. Payments under some of these contracts depend on factors such as the successful enrollment of patients, site initiation and the completion of clinical milestones. The Company makes estimates of its accrued expenses as of each balance sheet date in its financial statements based on facts and circumstances known at that time. In accruing service fees, the Company estimates the time period over which services will be performed and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from its estimate, the Company adjusts the accrual or prepaid expense balance accordingly. Historically, the Company’s estimated accrued liabilities have materially approximated actual expense incurred.

Revenue Recognition

Revenue Recognition

Revenue generally consists of license revenue with upfront payments and development milestones considered probable of achievement.

Revenue is recognized when control of the promised goods or services is transferred to the Company’s customers in an amount that reflects the consideration the Company expects to receive from its customers in exchange for those goods and services. This process involves identifying the contract with a customer, determining the performance obligations in the contract, determining the transaction price, allocating the contract price to the distinct performance obligations in the contract, and recognizing revenue when or as the Company satisfies the performance obligation(s).

At contract inception, the Company assesses the goods and services promised within each contract and assesses whether each promised good or service is distinct and determines that those are performance obligations. A performance obligation is considered distinct from other obligations in a contract when it provides a benefit to the customer either on its own or together with other resources that are readily available to the customer and is separately identified in the contract. The Company considers factors such as the research, manufacturing and commercialization capabilities of the collaboration partner and the availability of the associated expertise in the general marketplace. The Company considers a performance obligation satisfied once the Company has transferred control of a good or service to the customer, meaning the customer has the ability to use and obtain the benefit of the good or service. The Company recognizes revenue for satisfied performance obligations only when the Company determines there are no uncertainties regarding payment terms or transfer of control.

Collaborative Arrangements

The Company enters into collaborative arrangements with partners that may include payment to the Company of one or more of the following: (i) license fees; (ii) payments related to the achievement of developmental, regulatory, or commercial milestones; and (iii) royalties on net sales of licensed products.  Where a portion of non‑refundable upfront fees or other payments received are allocated to continuing performance obligations under the terms of a collaborative arrangement, they are recorded as contract liabilities and recognized as revenue when (or as) the underlying performance obligation is satisfied.  

As part of the accounting for these arrangements, the Company must develop estimates and assumptions that require judgment to determine the underlying stand-alone selling price for each performance obligation which determines how the transaction price is allocated among the performance obligation(s). The stand-alone selling price may include items such as forecasted revenues, development timelines, discount rates, and probabilities of technical and regulatory success. The Company evaluates each performance obligation to determine if it can be satisfied at a point in time or over time. In addition, variable consideration must be evaluated to determine if it is constrained and, therefore, excluded from the transaction price.

License Fees

If a license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company recognizes revenues from non-refundable, upfront fees allocated to the license when the license is transferred to the licensee and the licensee is able to use and benefit from the license. For licenses that are bundled with other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license, collaboration or other revenues and earnings in the period of adjustment.

Milestone Payments

At the inception of each arrangement that includes milestone payments (variable consideration), the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price. If it is probable that a milestone event would occur at the inception of the arrangement, the associated milestone value is included in the transaction price. Milestone payments that are not within the Company’s control, such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received. The transaction price is then allocated to each performance obligation on a relative stand-alone selling price basis, for which the Company recognizes revenue as or when the performance obligations under the contract are satisfied. At the end of each reporting period, the Company evaluates the probability of achievement of such milestones and any related constraint(s), and if necessary, may adjust the Company’s estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license, collaboration or other revenues and earnings in the period of adjustment.

Royalties

For arrangements that include sales-based royalties, including milestone payments based on the level of sales, and for which the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). To date, the Company has not recognized any royalty revenue resulting from its collaborative arrangements.

Stock-Based Compensation

Stock-Based Compensation

Stock-based compensation expense represents the cost of the grant date fair value of stock awards, including stock options, and stock purchase rights granted to employees and members of the Company’s board of directors. For awards with time-based vesting provisions, the Company estimates the fair value of stock options on the date of grant using the Black-Scholes option pricing model and recognizes the expense over the requisite service period of the awards, which is generally the vesting period, on a straight-line basis. For awards with performance-based vesting provisions, the Company estimates the fair value of stock option grants on the date of grant, or the date when all of the terms of the grant have been agreed to, if later, and recognizes the expense based on the probability of the occurrence of the individual milestones at each reporting period. The expense is recognized over the implicit service period that commences once management believes the performance criteria are probable of being met.  For purchase rights, the Company estimates the fair value of the purchase as of the plan enrollment date and recognizes expense on a straight-line basis over the applicable offering period.  The Company accounts for forfeitures when they occur and reverses any compensation cost previously recognized for awards for which the requisite service has not been completed, in the period that the award is forfeited.

Net Loss Per Share

Net Loss Per Share

Basic and diluted net loss per common share for the periods presented is computed by dividing net loss by the weighted-average number of common shares outstanding during the respective periods, without consideration of common stock equivalents as they are anti-dilutive. Common stock equivalents that could potentially dilute earnings in the future are comprised of options to purchase shares of common stock outstanding under the Company’s equity incentive plan and warrants for the purchase of shares of common stock. For all periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding due to the Company’s net loss position.

Common stock equivalents from potentially dilutive securities that are not included in the calculation of diluted net loss per share, because to do so would be anti-dilutive, are as follows:

 

 

 

Three Months Ended

March 31,

 

 

 

2020

 

 

2019

 

Common stock options and awards

 

 

4,798,269

 

 

 

4,262,170

 

Common stock warrants

 

 

66,514

 

 

 

67,238

 

Total

 

 

4,864,783

 

 

 

4,329,408

 

Recently Issued Accounting Pronouncements

Recently Issued Accounting Pronouncements

The Company has evaluated all recent accounting pronouncements issued by the Financial Accounting Standards Board in the form of Accounting Standards Updates through the date these financial statements were available to be issued and found no recent accounting pronouncements issued, but not yet effective that when adopted, would have a material impact on the financial statements of the Company.

v3.20.1
Summary of Significant Accounting Policies (Tables)
3 Months Ended
Mar. 31, 2020
Accounting Policies [Abstract]  
Schedule of Common Stock Equivalents from Potentially Dilutive Securities Not Included in Calculation of Diluted Net Loss Per Share

Common stock equivalents from potentially dilutive securities that are not included in the calculation of diluted net loss per share, because to do so would be anti-dilutive, are as follows:

 

 

 

Three Months Ended

March 31,

 

 

 

2020

 

 

2019

 

Common stock options and awards

 

 

4,798,269

 

 

 

4,262,170

 

Common stock warrants

 

 

66,514

 

 

 

67,238

 

Total

 

 

4,864,783

 

 

 

4,329,408

 

v3.20.1
Fair Value of Financial Instruments (Tables)
3 Months Ended
Mar. 31, 2020
Fair Value Disclosures [Abstract]  
Summary of Fair Values of Assets Measured on a Recurring Basis

The Company did not have any fair value measurements on a recurring basis as of March 31, 2020. The following table summarizes the Company’s assets that required fair value measurements on a recurring basis as of December 31, 2019 and their respective input levels based on the fair value hierarchy (in thousands):

 

 

 

 

 

 

 

Fair Value Measurements at End of Period Using:

 

 

 

Total

 

 

Quoted Market

Prices for

Identical Assets

(Level 1)

 

 

Significant

Other

Observable

Inputs

(Level 2)

 

 

Significant

Unobservable

Inputs

(Level 3)

 

December 31, 2019

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Marketable securities:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Corporate debt securities

 

$

3,700

 

 

$

 

 

$

3,700

 

 

$

 

Commercial paper

 

 

5,485

 

 

 

 

 

 

5,485

 

 

 

 

Asset-backed securities

 

 

3,650

 

 

 

 

 

 

3,650

 

 

 

 

 

 

$

12,835

 

 

$

 

 

$

12,835

 

 

$

 

v3.20.1
Certain Financial Statement Caption Information (Tables)
3 Months Ended
Mar. 31, 2020
Balance Sheet Related Disclosures [Abstract]  
Summary of Marketable Securities The following is a summary of the Company’s marketable securities as of December 31, 2019 (in thousands):

 

 

Maturity

(in years)

 

Amortized Cost

 

 

Unrealized Gain

 

 

Unrealized Loss

 

 

Fair Value

 

December 31, 2019

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Corporate debt securities

 

1 or less

 

$

2,699

 

 

$

1

 

 

$

 

 

$

2,700

 

Corporate debt securities

 

>1 and <5

 

 

999

 

 

 

1

 

 

 

 

 

 

1,000

 

Commercial paper

 

1 or less

 

 

5,481

 

 

 

4

 

 

 

 

 

 

5,485

 

Asset-backed securities

 

1 or less

 

 

3,646

 

 

 

4

 

 

 

 

 

 

3,650

 

 

 

 

 

$

12,825

 

 

$

10

 

 

$

-

 

 

$

12,835

 

 

Components of Accrued Liabilities

Accrued liabilities are comprised of (in thousands):

 

 

 

March 31,

2020

 

 

December 31,

2019

 

Clinical trial expenses

 

$

405

 

 

$

2,404

 

Payroll and other employee-related expenses

 

 

4,106

 

 

 

1,116

 

Contract manufacturing services

 

 

329

 

 

 

387

 

Current lease liability

 

 

435

 

 

 

416

 

Professional fees

 

 

377

 

 

 

330

 

Interest payable

 

 

34

 

 

 

37

 

Other

 

 

344

 

 

 

552

 

Total accrued liabilities

 

$

6,030

 

 

$

5,242

 

v3.20.1
Notes Payable (Tables)
3 Months Ended
Mar. 31, 2020
Debt Disclosure [Abstract]  
Schedule of Aggregate Carrying Amounts of Term Loans

The aggregate carrying amounts of the Term Loans are comprised of the following (in thousands):

 

 

 

March 31,

2020

 

 

December 31,

2019

 

Principal

 

$

4,583

 

 

$

5,000

 

Add: accreted liability for final payment fee

 

 

398

 

 

 

138

 

Less: unamortized discount

 

 

 

 

 

(394

)

 

 

$

4,981

 

 

$

4,744

 

 

v3.20.1
Stockholders' Equity (Tables)
3 Months Ended
Mar. 31, 2020
Equity [Abstract]  
Schedule of Common Stock Reserved for Future Issuance

Common stock reserved for future issuance as of March 31, 2020 is as follows:

 

Issued and Outstanding:

 

 

 

 

Stock options and awards

 

 

4,798,269

 

Warrants for common stock

 

 

66,514

 

Shares reserved for issuance under the 2017 Employee Stock

   Purchase Plan

 

 

725,847

 

Shares reserved for future award grants

 

 

1,020,458

 

Total

 

 

6,611,088

 

Summary of Allocation of Non-Cash Stock-Based Compensation Expense for All Stock Awards

The following table summarizes the allocation of the Company’s non-cash stock-based compensation expense for all stock awards during the three months ended March 31, 2020 and 2019 (in thousands): 

 

 

 

Three Months Ended

March 31,

 

 

 

2020

 

 

2019

 

Research and development

 

$

364

 

 

$

746

 

General and administrative

 

 

1,150

 

 

 

1,254

 

Total

 

$

1,514

 

 

$

2,000

 

 

v3.20.1
Organization and Basis of Presentation - Additional Information (Details)
$ in Thousands
3 Months Ended
Mar. 31, 2020
USD ($)
Segment
Dec. 31, 2019
USD ($)
Mar. 31, 2019
USD ($)
Dec. 31, 2018
USD ($)
Organization Consolidation And Presentation Of Financial Statements [Abstract]        
Number of operating segment | Segment 1      
Cash and cash equivalents $ 14,232 $ 8,986 $ 30,998 $ 40,813
Accumulated deficit $ 289,680 $ 279,400    
v3.20.1
Summary of Significant Accounting Policies - Schedule of Common Stock Equivalents from Potentially Dilutive Securities Not Included in Calculation of Diluted Net Loss Per Share (Details) - shares
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]    
Potential dilutive securities not included in calculation of diluted net loss per share 4,864,783 4,329,408
Common Stock Options and Awards    
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]    
Potential dilutive securities not included in calculation of diluted net loss per share 4,798,269 4,262,170
Common Stock Warrants    
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]    
Potential dilutive securities not included in calculation of diluted net loss per share 66,514 67,238
v3.20.1
Fair Value of Financial Instruments - Summary of Fair Values of Assets Measured on a Recurring Basis (Details) - Fair Value Measured on Recurring Basis
$ in Thousands
Dec. 31, 2019
USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Marketable securities $ 12,835
Significant Other Observable Inputs (Level 2)  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Marketable securities 12,835
Corporate Debt Securities  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Marketable securities 3,700
Corporate Debt Securities | Significant Other Observable Inputs (Level 2)  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Marketable securities 3,700
Commercial Paper  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Marketable securities 5,485
Commercial Paper | Significant Other Observable Inputs (Level 2)  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Marketable securities 5,485
Asset-backed Securities  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Marketable securities 3,650
Asset-backed Securities | Significant Other Observable Inputs (Level 2)  
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]  
Marketable securities $ 3,650
v3.20.1
Fair Value of Financial Instruments - Additional Information (Details) - USD ($)
Mar. 31, 2020
Dec. 31, 2019
Mar. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Investments, transfer of Level 1 to Level 2 $ 0   $ 0
Notes payable, current portion 4,981,000 $ 4,744,000  
Money Market Funds      
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]      
Investments in money market funds measured at fair value using net asset value per share $ 4,200,000 $ 6,300,000  
v3.20.1
Certain Financial Statement Caption Information - Additional Information (Details) - USD ($)
3 Months Ended
Mar. 31, 2020
Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]    
Marketable securities $ 0 $ 12,835,000
Other-than-temporary impairments during period 0  
Restructuring charges 3,500,000  
Severance and other related termination costs included in accrued liabilities $ 3,300,000  
v3.20.1
Certain Financial Statement Caption Information - Summary of Marketable Securities (Details)
$ in Thousands
Dec. 31, 2019
USD ($)
Schedule of Available-for-sale Securities [Line Items]  
Amortized Cost $ 12,825
Unrealized Gain 10
Fair Value 12,835
Corporate Debt Securities | Maturity (in years) 1 or Less  
Schedule of Available-for-sale Securities [Line Items]  
Amortized Cost 2,699
Unrealized Gain 1
Fair Value 2,700
Corporate Debt Securities | Maturity More Than 1 Year and Less Than 5 Years  
Schedule of Available-for-sale Securities [Line Items]  
Amortized Cost 999
Unrealized Gain 1
Fair Value 1,000
Commercial Paper | Maturity (in years) 1 or Less  
Schedule of Available-for-sale Securities [Line Items]  
Amortized Cost 5,481
Unrealized Gain 4
Fair Value 5,485
Asset-backed Securities | Maturity (in years) 1 or Less  
Schedule of Available-for-sale Securities [Line Items]  
Amortized Cost 3,646
Unrealized Gain 4
Fair Value $ 3,650
v3.20.1
Certain Financial Statement Caption Information - Components of Accrued Liabilities (Details) - USD ($)
$ in Thousands
Mar. 31, 2020
Dec. 31, 2019
Balance Sheet Related Disclosures [Abstract]    
Clinical trial expenses $ 405 $ 2,404
Payroll and other employee-related expenses 4,106 1,116
Contract manufacturing services 329 387
Current lease liability 435 416
Professional fees 377 330
Interest payable 34 37
Other 344 552
Total accrued liabilities $ 6,030 $ 5,242
v3.20.1
Notes Payable - Additional Information (Details)
$ / shares in Units, $ in Millions
3 Months Ended
Apr. 10, 2020
USD ($)
Oct. 31, 2019
USD ($)
May 18, 2018
USD ($)
$ / shares
shares
Oct. 30, 2015
USD ($)
Lender
Mar. 31, 2020
2015 Loan Agreement          
Debt Instrument [Line Items]          
Number of Lenders | Lender       2  
Loans       $ 18.0  
Debt instrument, frequency of periodic payment         due in monthly principal and interest payments, with final maturity of the Initial Loans in May 2019.
Debt instrument maturity       May 31, 2019  
Debt instrument, final payment fee, percentage       7.95%  
2018 Loan Agreement | Subsequent Event          
Debt Instrument [Line Items]          
Prepayment of term loans $ 4.9        
2018 Loan Agreement | Term Loans          
Debt Instrument [Line Items]          
Loans     $ 26.5    
Debt instrument maturity         Dec. 01, 2022
Debt instrument, final payment fee, percentage     7.95%    
Proceeds from term loans     $ 8.6    
Debt instrument, interest rate terms         The Term Loans would have matured on December 1, 2022 (the Maturity Date) and bore interest at a floating per annum rate equal to the greater of (i) 8.50% and (ii) the sum of (a) the prime rate reported in the Wall Street Journal on the last business day of the month that immediately proceeds the month in which the interest will accrue, plus (b) 3.75%.
Floating rate of interest         8.50%
Warrants to purchase shares of common stock | shares     56,578    
Warrant to purchase common stock, exercise price | $ / shares     $ 9.35    
Fair value of warrants at the date of issuance     $ 0.5    
2018 Loan Agreement | Term Loans | Expected Term | Significant Unobservable Inputs (Level 3)          
Debt Instrument [Line Items]          
Expected term in years     10 years    
2018 Loan Agreement | Term Loans | Volatility | Significant Unobservable Inputs (Level 3)          
Debt Instrument [Line Items]          
Warrant rate     0.856    
2018 Loan Agreement | Term Loans | Risk Free | Significant Unobservable Inputs (Level 3)          
Debt Instrument [Line Items]          
Warrant rate     0.031    
2018 Loan Agreement | Term Loans | Expected Dividend | Significant Unobservable Inputs (Level 3)          
Debt Instrument [Line Items]          
Warrant rate     0.00    
2018 Loan Agreement | Term Loans | Subsequent Event          
Debt Instrument [Line Items]          
Prepayment of term loans $ 4.4        
2018 Loan Agreement | Term Loans | Prime Rate          
Debt Instrument [Line Items]          
Debt instrument, basis spread on variable rate     3.75%    
2018 Loan Agreement | Term Loans | Minimum          
Debt Instrument [Line Items]          
Floating rate of interest     8.50%    
Second Amendment Loan Agreement          
Debt Instrument [Line Items]          
Prepayment of term loans   $ 23.3      
Second Amendment Loan Agreement | Term Loans          
Debt Instrument [Line Items]          
Prepayment of term loans   $ 21.5      
v3.20.1
Notes Payable - Schedule of Aggregate Carrying Amounts of Term Loans (Details) - Loan Agreement - USD ($)
$ in Thousands
Mar. 31, 2020
Dec. 31, 2019
Debt Instrument [Line Items]    
Debt Instrument, Type [Extensible List] toca:TermLoanMember toca:TermLoanMember
Principal $ 4,583 $ 5,000
Add: accreted liability for final payment fee 398 138
Less: unamortized discount   (394)
Loans, aggregate carrying amount $ 4,981 $ 4,744
v3.20.1
Stockholders' Equity - Additional Information (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended
Mar. 31, 2020
Mar. 31, 2020
Mar. 31, 2019
Class Of Stock [Line Items]      
Proceeds from issuance of common stock   $ 10 $ 248
Performance-Based Vesting Provisions      
Class Of Stock [Line Items]      
Stock options outstanding 188,651 188,651  
ATM Facility      
Class Of Stock [Line Items]      
Common stock issued, shares 760,089 0 146,398
Weighted average sales price, per share     $ 10.69
Proceeds from issuance of common stock $ 7,700   $ 1,500
v3.20.1
Stockholders' Equity - Schedule of Common Stock Reserved for Future Issuance (Details)
Mar. 31, 2020
shares
Class Of Stock [Line Items]  
Common stock reserved for future issuance 6,611,088
Shares Reserved for Issuance Under the 2017 Employee Stock Purchase Plan  
Class Of Stock [Line Items]  
Common stock reserved for future issuance 725,847
Warrants  
Class Of Stock [Line Items]  
Common stock reserved for future issuance 66,514
Stock Options and Awards  
Class Of Stock [Line Items]  
Common stock reserved for future issuance 4,798,269
Shares Reserved for Future Award Grants  
Class Of Stock [Line Items]  
Common stock reserved for future issuance 1,020,458