Ownership Submission
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 *
CHAMPSI FARAH
  2. Issuer Name and Ticker or Trading Symbol
CHIMERIX INC [CMRX]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
ONE EMBARCADERO CENTER, 37TH FLOOR
3. Date of Earliest Transaction (Month/Day/Year)
10/23/2013
(Street)

SAN FRANCISCO, CA 94111
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ 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 10/23/2013   S   447,499 (1) D $ 15.51 1,714,330 I See footnote (2)

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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
CHAMPSI FARAH
ONE EMBARCADERO CENTER, 37TH FLOOR
SAN FRANCISCO, CA 94111
  X      

Signatures

 /s/ Farah Champsi   10/23/2013
**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) Shares sold to the underwriters in connection with the sale of Common Stock by Ms. Champsi as follows: 409,872 shares sold by Alta Biopharma Partners III, L.P.; 27,526 shares sold by Alta Biopharma Partners III GmbH & Co. Beteiligungs KG; and 10,101 shares sold by Alta Embarcadero Biopharma Partners III, LLC.
(2) Securities held by Alta Biopharma Partners III, L.P., Alta Biopharma Partners III GmbH & Co. Beteiligungs KG and Alta Embarcadero Biopharma Partners III, LLC (collectively, the "Alta Funds"). The directors of Alta Biopharma Management III, LLC, which is a general partner of Alta Biopharma Partners III, L.P., the managing limited partner of Alta Biopharma Partners III GmbH & Co. Beteiligungs KG, and the manager of Alta Embarcadero Biopharma Partners III, LLC, exercise sole dispositive and voting power over the securities owned by the Alta Funds. Ms. Champsi, a director of Alta Biopharma Management III, LLC and a manager of Alta Embarcadero Biopharma Partners III, LLC, may be deemed to beneficially own the securities. Ms. Champsi disclaims beneficial ownership over these securities, except to the extent of her pecuniary interest therein.

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