UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D
Under the Securities Exchange Act of 1934
(Amendment No. 1)*

Sientra, Inc.
(Name of Issuer)
Common Stock, $0.01 par value per share
(Title of Class of Securities)
82621J105
(CUSIP Number)
Robert Liptak
Clarus Ventures, LLC
101 Main Street, Suite 1210
Cambridge, MA 02142
(617) 949-2200
(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)
May 4, 2022
(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.  ☐

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule §240.13d-7 for other parties to whom copies are to be sent.

 
*	The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.	
The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

 

					
CUSIP No. 82621J105	  	13D	  	Page 2 of 14 Pages	

  1  	 	  NAMES OF REPORTING PERSONS.
 
  Clarus Lifesciences I, L.P.	
  2	 	  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
 
  (a)  ☐        (b)  ☒	
  3	 	  SEC USE ONLY
 	
  4	 	  SOURCE OF FUNDS (SEE INSTRUCTIONS)
 
  WC	
  5	 	  CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)
 
  ☐	
  6	 	  CITIZENSHIP OR PLACE OF ORGANIZATION
 
  Delaware	
							
NUMBER OF
SHARES
 BENEFICIALLY 
OWNED BY
EACH
REPORTING
PERSON
WITH
 	  	  7  	  	  SOLE VOTING POWER
 
  2,730,765	
	  	  8	  	  SHARED VOTING POWER
 
  0	
	  	  9	  	  SOLE DISPOSITIVE POWER
 
  2,730,765	
	  	10	  	  SHARED DISPOSITIVE POWER
 
  0	
							
11  	 	  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
  2,730,765	
12	 	  CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
 
  ☐	
13	 	  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
  4.4%	
14	 	  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
 
  PN	

					
CUSIP No. 82621J105	  	13D	  	Page 3 of 14 Pages	

  1  	 	  NAMES OF REPORTING PERSONS.
 
  Clarus Ventures I Management, L.P.	
  2	 	  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
 
  (a)  ☐        (b)  ☒	
  3	 	  SEC USE ONLY
 	
  4	 	  SOURCE OF FUNDS (SEE INSTRUCTIONS)
 
  OO	
  5	 	  CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)
 
  ☐	
  6	 	  CITIZENSHIP OR PLACE OF ORGANIZATION
 
  Delaware	
							
NUMBER OF
SHARES
 BENEFICIALLY 
OWNED BY
EACH
REPORTING
PERSON
WITH
 	  	  7  	  	  SOLE VOTING POWER
 
  2,730,765	
	  	  8	  	  SHARED VOTING POWER
 
  0	
	  	  9	  	  SOLE DISPOSITIVE POWER
 
  2,730,765	
	  	10	  	  SHARED DISPOSITIVE POWER
 
  0	
							
11  	 	  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
  2,730,765	
12	 	  CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
 
  ☐	
13	 	  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
  4.4%	
14	 	  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
 
  PN	

					
CUSIP No. 82621J105	  	13D	  	Page 4 of 14 Pages	

  1  	 	  NAMES OF REPORTING PERSONS.
 
  Blackstone Clarus I L.L.C.	
  2	 	  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
 
  (a)  ☐        (b)  ☒	
  3	 	  SEC USE ONLY
 	
  4	 	  SOURCE OF FUNDS (SEE INSTRUCTIONS)
 
  OO	
  5	 	  CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)
 
  ☐	
  6	 	  CITIZENSHIP OR PLACE OF ORGANIZATION
 
  Delaware	
							
NUMBER OF
SHARES
 BENEFICIALLY 
OWNED BY
EACH
REPORTING
PERSON
WITH
 	  	  7  	  	  SOLE VOTING POWER
 
  2,730,765	
	  	  8	  	  SHARED VOTING POWER
 
  0	
	  	  9	  	  SOLE DISPOSITIVE POWER
 
  2,730,765	
	  	10	  	  SHARED DISPOSITIVE POWER
 
  0	
							
11  	 	  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
  2,730,765	
12	 	  CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
 
  ☐	
13	 	  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
  4.4%	
14	 	  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
 
  OO	

					
CUSIP No. 82621J105	  	13D	  	Page 5 of 14 Pages	

  1  	 	  NAMES OF REPORTING PERSONS.
 
  Blackstone Holdings II L.P.	
  2	 	  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
 
  (a)  ☐        (b)  ☒	
  3	 	  SEC USE ONLY
 	
  4	 	  SOURCE OF FUNDS (SEE INSTRUCTIONS)
 
  OO	
  5	 	  CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)
 
  ☐	
  6	 	  CITIZENSHIP OR PLACE OF ORGANIZATION
 
  Delaware	
							
NUMBER OF
SHARES
 BENEFICIALLY 
OWNED BY
EACH
REPORTING
PERSON
WITH
 	  	  7  	  	  SOLE VOTING POWER
 
  2,730,765	
	  	  8	  	  SHARED VOTING POWER
 
  0	
	  	  9	  	  SOLE DISPOSITIVE POWER
 
  2,730,765	
	  	10	  	  SHARED DISPOSITIVE POWER
 
  0	
							
11  	 	  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
  2,730,765	
12	 	  CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
 
  ☐	
13	 	  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
  4.4%	
14	 	  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
 
  PN	

					
CUSIP No. 82621J105	  	13D	  	Page 6 of 14 Pages	

  1  	 	  NAMES OF REPORTING PERSONS.
 
  Blackstone Holdings I/II GP L.L.C.	
  2	 	  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
 
  (a)  ☐        (b)  ☒	
  3	 	  SEC USE ONLY
 	
  4	 	  SOURCE OF FUNDS (SEE INSTRUCTIONS)
 
  OO	
  5	 	  CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)
 
  ☐	
  6	 	  CITIZENSHIP OR PLACE OF ORGANIZATION
 
  Delaware	
							
NUMBER OF
SHARES
 BENEFICIALLY 
OWNED BY
EACH
REPORTING
PERSON
WITH
 	  	  7  	  	  SOLE VOTING POWER
 
  2,730,765	
	  	  8	  	  SHARED VOTING POWER
 
  0	
	  	  9	  	  SOLE DISPOSITIVE POWER
 
  2,730,765	
	  	10	  	  SHARED DISPOSITIVE POWER
 
  0	
							
11  	 	  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
  2,730,765	
12	 	  CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
 
  ☐	
13	 	  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
  4.4%	
14	 	  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
 
  OO	

					
CUSIP No. 82621J105	  	13D	  	Page 7 of 14 Pages	

  1  	 	  NAMES OF REPORTING PERSONS.
 
  Blackstone Inc.	
  2	 	  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
 
  (a)  ☐        (b)  ☒	
  3	 	  SEC USE ONLY
 	
  4	 	  SOURCE OF FUNDS (SEE INSTRUCTIONS)
 
  OO	
  5	 	  CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)
 
  ☐	
  6	 	  CITIZENSHIP OR PLACE OF ORGANIZATION
 
  Delaware	
							
NUMBER OF
SHARES
 BENEFICIALLY 
OWNED BY
EACH
REPORTING
PERSON
WITH
 	  	  7  	  	  SOLE VOTING POWER
 
  2,730,765	
	  	  8	  	  SHARED VOTING POWER
 
  0	
	  	  9	  	  SOLE DISPOSITIVE POWER
 
  2,730,765	
	  	10	  	  SHARED DISPOSITIVE POWER
 
  0	
							
11  	 	  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
  2,730,765	
12	 	  CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
 
  ☐	
13	 	  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
  4.4%	
14	 	  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
 
  CO	

					
CUSIP No. 82621J105	  	13D	  	Page 8 of 14 Pages	

  1  	 	  NAMES OF REPORTING PERSONS.
 
  Blackstone Group Management L.L.C.	
  2	 	  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
 
  (a)  ☐        (b)  ☒	
  3	 	  SEC USE ONLY
 	
  4	 	  SOURCE OF FUNDS (SEE INSTRUCTIONS)
 
  OO	
  5	 	  CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)
 
  ☐	
  6	 	  CITIZENSHIP OR PLACE OF ORGANIZATION
 
  Delaware	
							
NUMBER OF
SHARES
 BENEFICIALLY 
OWNED BY
EACH
REPORTING
PERSON
WITH
 	  	  7  	  	  SOLE VOTING POWER
 
  2,730,765	
	  	  8	  	  SHARED VOTING POWER
 
  0	
	  	  9	  	  SOLE DISPOSITIVE POWER
 
  2,730,765	
	  	10	  	  SHARED DISPOSITIVE POWER
 
  0	
							
11  	 	  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
  2,730,765	
12	 	  CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
 
  ☐	
13	 	  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
  4.4%	
14	 	  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
 
  OO	

					
CUSIP No. 82621J105	  	13D	  	Page 9 of 14 Pages	

  1  	 	  NAMES OF REPORTING PERSONS.
 
  Stephen A. Schwarzman	
  2	 	  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
 
  (a)  ☐        (b)  ☒	
  3	 	  SEC USE ONLY
 	
  4	 	  SOURCE OF FUNDS (SEE INSTRUCTIONS)
 
  OO	
  5	 	  CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)
 
  ☐	
  6	 	  CITIZENSHIP OR PLACE OF ORGANIZATION
 
  United States of America	
							
NUMBER OF
SHARES
 BENEFICIALLY 
OWNED BY
EACH
REPORTING
PERSON
WITH
 	  	  7  	  	  SOLE VOTING POWER
 
  2,730,765	
	  	  8	  	  SHARED VOTING POWER
 
  0	
	  	  9	  	  SOLE DISPOSITIVE POWER
 
  2,730,765	
	  	10	  	  SHARED DISPOSITIVE POWER
 
  0	
							
11  	 	  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 
  2,730,765	
12	 	  CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
 
  ☐	
13	 	  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
 
  4.4%	
14	 	  TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
 
  IN	

					
CUSIP No. 82621J105	  	13D	  	Page 10 of 14 Pages	
 
This Amendment No. 1 (“Amendment”) to the statement on Schedule 13D amends and supplements the initial statement on Schedule 13D filed with the Securities and Exchange Commission on January 11, 2019 (as amended, the “Schedule 13D”), relating to the shares of Common Stock, par value $0.01 per share (the “Common Stock”), of Sientra, Inc. (the “Issuer”).
Certain terms used but not defined in this Amendment have the meanings assigned thereto in the Schedule 13D. Except as specifically provided herein, this Amendment does not modify any of the information previously reported in the Schedule 13D. This Amendment constitutes an exit filing of the Reporting Persons, in respect of the Common Stock beneficially owned by the Reporting Persons.
Item 2. Identity and Background.
Item 2 of the Schedule 13D is hereby amended by incorporating herein by reference the information set forth on the updated Schedule I attached hereto.
Item 4. Purpose of Transaction
Item 4 of the Schedule 13D is hereby amended and supplemented as follows:
Nicholas Simon, an employee of Blackstone Inc. or its affiliates, no longer serves on the board of directors of the Issuer.
Item 5. Interest in Securities of the Issuer.
Item 5 of the Schedule 13D is hereby amended and restated as follows:
(a) and (b). Calculations of the percentage of Common Stock beneficially owned is based upon 62,606,616 shares of Common Stock outstanding as of April 12, 2022, as reported in the Issuer’s Definitive Proxy Statement filed with the Securities and Exchange Commission on April 29, 2022.
The aggregate number and percentage of shares of Common Stock beneficially owned by each Reporting Person and, for each Reporting Person, the number of shares of Common Stock as to which there is sole power to vote or to direct the vote, shared power to vote or to direct the vote, sole power to dispose or to direct the disposition, or shared power to dispose or to direct the disposition are set forth on rows 7 through 11 and row 13 of the cover pages of this Schedule 13D and are incorporated herein by reference.
As of the date hereof, Clarus Lifesciences I, L.P. (the “Fund”) directly owns 2,730,765 shares of Common Stock. Not included on this Schedule 13D are 84,699 shares of Common Stock held by Nicholas Simon for the benefit of the Fund.
Clarus Ventures I Management, L.P. (“Clarus GP”) is the general partner of the Fund. Blackstone Clarus I L.L.C. is the general partner of Clarus GP. The sole member of Blackstone Clarus I L.L.C. is Blackstone Holdings II L.P. The general partner of Blackstone Holdings II L.P. is Blackstone Holdings I/II GP L.L.C. The sole member of Blackstone Holdings I/II GP L.L.C. is Blackstone Inc. The sole holder of the Series II preferred stock of Blackstone Inc. is Blackstone Group Management L.L.C. Blackstone Group Management L.L.C. is wholly-owned by Blackstone’s senior managing directors and controlled by its founder, Stephen A. Schwarzman.
Neither the filing of this Schedule 13D nor any of its contents shall be deemed to constitute an admission that any of the Reporting Persons (other than the Fund) is the beneficial owner of the shares of Common Stock referred to herein for purposes of Section 13(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or for any other purpose, and such beneficial ownership is expressly disclaimed (other than by the Fund). The filing of this statement should not be construed to be an admission that any member of the Reporting Persons are members of a “group” for the purposes of Sections 13(d) and 13(g) of the Exchange Act.

(c) None of the Reporting Persons has effected any transaction in the Common Stock during the past 60 days.
(d) To the best knowledge of the Reporting Persons, no person other than the Reporting Persons, or the partners, members, affiliates or shareholders of the Reporting Persons, has the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the securities beneficially owned by the Reporting Persons identified in this Item 5.
(e) The Reporting Persons no longer beneficially own more than five percent of the Common Stock.

SIGNATURE
After reasonable inquiry and to the best of its or his knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.
Date: May 4, 2022

CLARUS LIFESCIENCES I, L.P.	
By: Clarus Ventures I Management, L.P., its general partner	
By: Blackstone Clarus I L.L.C., its general partner	
		
By:	 	/s/ Omar Rehman	
Name:	 	Omar Rehman	
Title:	 	Chief Compliance Officer and Secretary	

CLARUS VENTURES I MANAGEMENT, L.P.	
By: Blackstone Clarus I L.L.C., its general partner	
		
By:	 	/s/ Omar Rehman	
Name:	 	Omar Rehman	
Title:	 	Chief Compliance Officer and Secretary	

BLACKSTONE CLARUS I L.L.C.	
		
By:	 	/s/ Omar Rehman	
Name:	 	Omar Rehman	
Title:	 	Chief Compliance Officer and Secretary	

BLACKSTONE HOLDINGS II L.P.	
By: Blackstone Holdings I/II GP L.L.C., its general partner	
		
By:	 	/s/ Tabea Hsi	
Name:	 	Tabea Hsi	
Title:	 	Senior Managing Director	

BLACKSTONE HOLDINGS I/II GP L.L.C.	
		
By:	 	/s/ Tabea Hsi	
Name:	 	Tabea Hsi	
Title:	 	Senior Managing Director	

			
BLACKSTONE INC.	
By: Blackstone Group Management L.L.C.,
its general partner	
		
By:	 	/s/ Tabea Hsi	
			
Name:	 	Tabea Hsi	
Title:	 	Senior Managing Director	

BLACKSTONE GROUP MANAGEMENT L.L.C.	
		
By:	 	/s/ Tabea Hsi	
			
Name:	 	Tabea Hsi	
Title:	 	Senior Managing Director	

/s/ Stephen A. Schwarzman	
Stephen A. Schwarzman	

SCHEDULE I
Executive Officers and Directors of Blackstone Inc.
The name and principal occupation of each director and executive officer of Blackstone Inc. are set forth below. The address for each person listed below is c/o Blackstone Inc., 345 Park Avenue, New York, New York 10154. All executive officers and directors listed are United States citizens other than The Right Honourable Brian Mulroney, who is a citizen of Canada, and Sir John Antony Hood, who is a citizen of New Zealand.
OFFICERS:

Name	  	Present Principal Occupation or Employment	
		
Stephen A. Schwarzman	  	Founder, Chairman and Chief Executive Officer of Blackstone Inc.	
		
Jonathan D. Gray	  	President, Chief Operating Officer of Blackstone Inc.	
		
Michael S. Chae	  	Chief Financial Officer of Blackstone Inc.	
		
John G. Finley	  	Chief Legal Officer of Blackstone Inc.	
DIRECTORS:

Name	  	Present Principal Occupation or Employment	
		
Stephen A. Schwarzman	  	Founder, Chairman and Chief Executive Officer of Blackstone Inc.	
		
Jonathan D. Gray	  	President, Chief Operating Officer of Blackstone Inc.	
		
Kelly A. Ayotte	  	Former United States Senator from New Hampshire	
		
Joseph P. Baratta	  	Global Head of Private Equity at Blackstone Inc.	
		
James W. Breyer	  	Founder and Chief Executive Officer of Breyer Capital	
		
Reginald J. Brown	  	Partner for the law firm, Kirkland & Ellis	
		
Sir John Antony Hood	  	Former President and Chief Executive Officer of the Robertson Foundation and Former Chair of the Rhodes Trust	
		
Rochelle B. Lazarus	  	Chairman Emeritus & Former Chief Executive Officer, Ogilvy & Mather Worldwide	
		
Jay O. Light	  	Dean Emeritus, Harvard Business School	
		
The Right Honourable Brian Mulroney	  	Senior Partner for the Montreal law firm, Norton Rose Fulbright Canada LLP	
		
William G. Parrett	  	Retired CEO of Deloitte Touche Tohmatsu and retired Senior Partner of Deloitte (USA)	
		
Ruth Porat	  	Chief Financial Officer of Alphabet Inc. and Google Inc.