SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
X	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* Moorin Jay (Last) (First) (Middle) C/O PROQUEST INVESTMENTS 90 NASSAU STREET, 5TH FLOOR (Street) PRINCETON NJ 08542-4520 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol ACHILLION PHARMACEUTICALS INC [ ACHN ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 12/16/2009
	4. If Amendment, Date of 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

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	12/16/2009		S		493,452	D	$3.5208(1)	2,733,854	I	See footnote(2)
Common Stock	12/17/2009		S		70,000	D	$3.2443(3)	2,663,854	I	See footnote(4)

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 Securities Underlying Derivative Security (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: 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
Warrants	$3.53							08/12/2008	08/12/2015	Common Stock	806,827		806,827	I	See footnote(5)

1. Name and Address of Reporting Person* Moorin Jay (Last) (First) (Middle) C/O PROQUEST INVESTMENTS 90 NASSAU STREET, 5TH FLOOR (Street) PRINCETON NJ 08542-4520 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* SCHREIBER ALAIN (Last) (First) (Middle) C/O PROQUEST INVESTMENTS 90 NASSAU STREET, 5TH FLOOR (Street) PRINCETON NJ 08542-4520 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* ProQuest Associates IV LLC (Last) (First) (Middle) 90 NASSAU STREET, 5TH FLOOR (Street) PRINCETON NJ 08542-4520 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* ProQuest Investments IV, L.P. (Last) (First) (Middle) 90 NASSAU STREET, 5TH FLOOR (Street) PRINCETON NJ 08542-4520 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. Constitutes the weighted average purchase price for multiple transactions reported on this line having prices per share ranging from $3.20 to $3.86. The Reporting Persons will provide upon request by the Commission staff, the issuer or a security holder of the issuer, full information regarding each separate transaction.

2. Of such shares: 911,285 are owned by ProQuest Investments III, L.P. ("Investments III"), of which ProQuest Associates III LLC ("Associates III") is the general partner, and 1,822,569 are owned by ProQuest Investments IV, L.P. ("Investments IV"), of which ProQuest Associates IV LLC ("Associates IV") is the general partner. Jay Moorin and Alain Schreiber are managing members of Associates III and Associates IV. Each of the Reporting Persons disclaims beneficial ownership of such securities except to the extent of each Reporting Person's pecuniary interest in such securities.

3. Constitutes the weighted average purchase price for multiple transactions reported on this line having prices per share ranging from $3.09 to $3.49. The Reporting Persons will provide upon request by the Commission staff, the issuer or a security holder of the issuer, full information regarding each separate transaction.

4. Of such shares: 887,952 are owned by ProQuest Investments III, L.P. ("Investments III"), of which ProQuest Associates III LLC ("Associates III") is the general partner, and 1,775,902 are owned by ProQuest Investments IV, L.P. ("Investments IV"), of which ProQuest Associates IV LLC ("Associates IV") is the general partner. Jay Moorin and Alain Schreiber are managing members of Associates III and Associates IV. Each of the Reporting Persons disclaims beneficial ownership of such securities except to the extent of each Reporting Person's pecuniary interest in such securities.

5. Of such warrants: 268,942 are owned by Investments III, and 537,885 are owned by Investments IV. Pursuant to a Securities Purchase Agreement, the Reporting Persons are not permitted to exercise any warrants, if, upon such exercise, the number of shares of Common Stock beneficially owned by the Reporting Person would exceed 9.99% of the number of shares of Common Stock then issued and outstanding, unless and until such limitation is no longer required by applicable NASDAQ Marketplace Rules. Each of the Reporting Persons disclaims beneficial ownership of such securities except to the extent of each Reporting Person's pecuniary interest in such securities.

Remarks:

	/s/ Pasquale De Angelis as Attorney-in-Fact	12/18/2009
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).
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