Ownership Submission
FORM 3
 UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF 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 *
  Moorin Jay
 2. Date of Event Requiring Statement (Month/Day/Year)
08/12/2008		 3. Issuer Name and Ticker or Trading Symbol
ACHILLION PHARMACEUTICALS INC [ACHN]
(Last)
(First)
(Middle)
C/O PROQUEST INVESTMENTS, 90 NASSAU STREET, 5TH FLOOR		 4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
(Street)

PRINCETON, NJ 08542-4520		 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 Beneficially Owned
1.Title of Security
(Instr. 4)		 2. Amount of Securities Beneficially Owned
(Instr. 4)		 3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)		 4. Nature of Indirect Beneficial Ownership
(Instr. 5)
Common Stock 3,227,306
I
See footnote (1)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)		 2. Date Exercisable and Expiration Date
(Month/Day/Year)		 3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)		 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)		 6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Warrants 08/12/2008 08/12/2015 Common Stock 806,827 $ 3.53 I See footnote (2)
Unit Warrants 02/12/2009 08/12/2009 See footnote (3) 1,385,195 $ 2.82 I See footnote (4)

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Moorin Jay
C/O PROQUEST INVESTMENTS
90 NASSAU STREET, 5TH FLOOR
PRINCETON, NJ 08542-4520		     X    
SCHREIBER ALAIN
C/O PROQUEST INVESTMENTS
90 NASSAU STREET, 5TH FLOOR
PRINCETON, NJ 08542-4520		     X    
ProQuest Investments IV, L.P.
90 NASSAU STREET, 5TH FLOOR
PRINCETON, NJ 08542-4520		     X    
ProQuest Associates IV LLC
90 NASSAU STREET, 5TH FLOOR
PRINCETON, NJ 08542-4520		     X    

Signatures

/s/ Pasquale De Angelis as Attorney-in-Fact 08/20/2008
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(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) Of such shares: 1,075,769 are owned by ProQuest Investments III, L.P. ("Investments III"), of which ProQuest Associates III LLC ("Associates III") is the general partner, and 2,151,537 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.
(2) 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 19.99% 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.
(3) The Unit Warrants are exercisable for Units, which consist of one share of Common Stock plus a warrant to purchase 0.25 shares of Common Stock. The Unit Warrants are exercisable for a minimum of $1,000,000.00 worth of Units per exercise. The warrants underlying the Unit Warrants will, upon exercise, be immediately exercisable at a price of $3.53 per share and will expire on 08/12/2015.
(4) Of such Unit Warrants: Unit Warrants consisting of 369,385 shares of Common Stock and warrants to purchase 92,346 shares of Common Stock are owned by Investments III, and Unit Warrants consisting of 738,771 shares of Common Stock and warrants to purchase 184,693 shares of Common Stock are owned by Investments IV. Pursuant to a Securities Purchase Agreement, the Reporting Persons are not permitted to exercise any Unit Warrants, if, upon such exercise, the number of shares of Common Stock beneficially owned by the Reporting Person would exceed 19.99% 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.

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