FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * Clarus Lifesciences I, L.P.   2. Issuer Name and Ticker or Trading Symbol ZOGENIX, INC. [ZGNX] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director __X__ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) C/O CLARUS VENTURES, LLC, 101 MAIN STREET, SUITE 1210 3. Date of Earliest Transaction (Month/Day/Year) 09/16/2011 (Street) CAMBRIDGE, MA 02142 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Filing(Check Applicable Line) ___ Form filed by One Reporting Person _X_ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 09/16/2011   P   3,500,000 A $ 2 9,482,439 I By Fund (1)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Clarus Lifesciences I, L.P. C/O CLARUS VENTURES, LLC 101 MAIN STREET, SUITE 1210 CAMBRIDGE, MA 02142		X
Clarus Ventures I Management, L.P. C/O CLARUS VENTURES, LLC 101 MAIN STREET, SUITE 1210 CAMBRIDGE, MA 02142		X
Clarus Ventures I, LLC C/O CLARUS VENTURES, LLC 101 MAIN STREET, SUITE 1210 CAMBRIDGE, MA 02142		X
LIPTAK ROBERT C/O CLARUS VENTURES, LLC 101 MAIN STREET, SUITE 1210 CAMBRIDGE, MA 02142		X
Simon Nicholas C/O CLARUS VENTURES, LLC 101 MAIN STREET, SUITE 1210 CAMBRIDGE, MA 02142		X
HENNER DENNIS C/O CLARUS VENTURES, LLC 101 MAIN STREET, SUITE 1210 CAMBRIDGE, MA 02142		X
GALAKATOS NICHOLAS C/O CLARUS VENTURES, LLC 101 MAIN STREET, SUITE 1210 CAMBRIDGE, MA 02142		X
WHEELER KURT C/O CLARUS VENTURES, LLC 101 MAIN STREET, SUITE 1210 CAMBRIDGE, MA 02142	X	X
STEINMETZ MICHAEL C/O CLARUS VENTURES, LLC 101 MAIN STREET, SUITE 1210 CAMBRIDGE, MA 02142		X

Signatures

/s/ Robert Liptak, Manager of Clarus Ventures I, LLC, general partner of Clarus Ventures I Management, L.P., general partner of Clarus Lifesciences I, L.P.		09/20/2011
**Signature of Reporting Person		Date
/s/ Robert Liptak, Manager of Clarus Ventures I, LLC, general partner of Clarus Ventures I Management, L.P.		09/20/2011
**Signature of Reporting Person		Date
/s/ Robert Liptak, Manager of Clarus Ventures I, LLC		09/20/2011
**Signature of Reporting Person		Date
/s/ Robert Liptak, as attorney-in-fact for Nicholas Simon		09/20/2011
**Signature of Reporting Person		Date
/s/ Robert Liptak		09/20/2011
**Signature of Reporting Person		Date
/s/ Robert Liptak, as attorney-in-fact for Dennis Henner		09/20/2011
**Signature of Reporting Person		Date
/s/ Robert Liptak, as attorney-in-fact for Nicholas Galakatos		09/20/2011
**Signature of Reporting Person		Date
/s/ Robert Liptak, as attorney-in-fact for Kurt Wheeler		09/20/2011
**Signature of Reporting Person		Date
/s/ Robert Liptak, as attorney-in-fact for Michael Steinmetz		09/20/2011
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Securities held of record by Clarus Lifesciences I, L.P. (the "Fund"). Clarus Ventures I Management, L.P. (the "GPLP"), as the sole general partner of the Fund, may be deemed to beneficially own certain of the shares held of record by the Fund. The GPLP disclaims beneficial ownership of all shares held of record by the Fund in which the GPLP does not have an actual pecuniary interest. Clarus Ventures I, LLC (the "GPLLC"), as the sole general partner of the GPLP, may be deemed to beneficially own certain of the shares held of record by the Fund. Each of Messrs. Galakatos, Henner, Liptak, Simon, Steinmetz and Wheeler, as individual Managing Directors of the GPLLC, may be deemed to beneficially own certain of the shares held of record by the Fund. Each of the GPLLC and Messrs. Galakatos, Henner, Liptak, Simon, Steinmetz and Wheeler disclaims beneficial ownership of all shares held of record by the Fund in which he does not have an actual pecuniary interest.

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