UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 --------------------------------- OMB APPROVAL --------------------------------- OMB Number: 3235-0145 Expires: December 31, 2005 Estimated average burden hours per response.............11 SCHEDULE 13D Under the Securities and Exchange Act of 1934 (Amendment No. 3 )* DIACRIN, INC. -------------------------------------------------------------------------------- (Name of Issuer) Common Stock, $.01 par value per share -------------------------------------------------------------------------------- (Title of Class of Securities) 25243N103 -------------------------------------------------------------------------------- (CUSIP Number) Jeffrey B. Steinberg HealthCare Ventures LLC 44 Nassau Street Princeton, New Jersey 08542 (609) 430-3900 -------------------------------------------------------------------------------- (Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications) August 21, 2003 -------------------------------------------------------------------------------- (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 Rule 13d-1(e), 13d-1(f) or 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 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 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. 25243N103 13D Page 1 of 11 Pages ________________________________________________________________________________ 1 NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) HealthCare Ventures II, L.P. ________________________________________________________________________________ 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [_] ________________________________________________________________________________ 3 SEC USE ONLY ________________________________________________________________________________ 4 SOURCE OF FUNDS* N/A ________________________________________________________________________________ 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_] ________________________________________________________________________________ 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ________________________________________________________________________________ 7 SOLE VOTING POWER NUMBER OF SHARES _________________________________________________________________ 8 SHARED VOTING POWER BENEFICIALLY OWNED BY 0 _________________________________________________________________ EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON _________________________________________________________________ 10 SHARED DISPOSITIVE POWER WITH 0 ________________________________________________________________________________ 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 ________________________________________________________________________________ 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0% ________________________________________________________________________________ 14 TYPE OF REPORTING PERSON* PN ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 25243N103 13D Page 2 of 11 Pages ________________________________________________________________________________ 1 NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) HealthCare Partners II, L.P. ________________________________________________________________________________ 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [_] ________________________________________________________________________________ 3 SEC USE ONLY ________________________________________________________________________________ 4 SOURCE OF FUNDS* N/A ________________________________________________________________________________ 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_] ________________________________________________________________________________ 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ________________________________________________________________________________ 7 SOLE VOTING POWER NUMBER OF SHARES _________________________________________________________________ 8 SHARED VOTING POWER BENEFICIALLY OWNED BY 0 _________________________________________________________________ EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON _________________________________________________________________ 10 SHARED DISPOSITIVE POWER WITH 0 ________________________________________________________________________________ 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 ________________________________________________________________________________ 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0% ________________________________________________________________________________ 14 TYPE OF REPORTING PERSON* PN ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 25243N103 13D Page 3 of 11 Pages ________________________________________________________________________________ 1 NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) HealthCare Ventures III, L.P. ________________________________________________________________________________ 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [_] ________________________________________________________________________________ 3 SEC USE ONLY ________________________________________________________________________________ 4 SOURCE OF FUNDS* N/A ________________________________________________________________________________ 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_] ________________________________________________________________________________ 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ________________________________________________________________________________ 7 SOLE VOTING POWER NUMBER OF SHARES _________________________________________________________________ 8 SHARED VOTING POWER BENEFICIALLY 0 OWNED BY _________________________________________________________________ EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON _________________________________________________________________ 10 SHARED DISPOSITIVE POWER WITH 0 ________________________________________________________________________________ 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 ________________________________________________________________________________ 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0% ________________________________________________________________________________ 14 TYPE OF REPORTING PERSON* PN ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 25243N103 13D Page 4 of 11 Pages ________________________________________________________________________________ 1 NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) HealthCare Partners III, L.P. ________________________________________________________________________________ 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [_] ________________________________________________________________________________ 3 SEC USE ONLY ________________________________________________________________________________ 4 SOURCE OF FUNDS* N/A ________________________________________________________________________________ 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_] ________________________________________________________________________________ 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ________________________________________________________________________________ 7 SOLE VOTING POWER NUMBER OF SHARES _________________________________________________________________ 8 SHARED VOTING POWER BENEFICIALLY OWNED BY 0 _________________________________________________________________ EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON _________________________________________________________________ 10 SHARED DISPOSITIVE POWER WITH 0 ________________________________________________________________________________ 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 ________________________________________________________________________________ 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0% ________________________________________________________________________________ 14 TYPE OF REPORTING PERSON* PN ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 25243N103 13D Page 5 of 11 Pages ________________________________________________________________________________ 1 NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) HealthCare Ventures IV, L.P. ________________________________________________________________________________ 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [_] ________________________________________________________________________________ 3 SEC USE ONLY ________________________________________________________________________________ 4 SOURCE OF FUNDS* N/A ________________________________________________________________________________ 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_] ________________________________________________________________________________ 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ________________________________________________________________________________ 7 SOLE VOTING POWER NUMBER OF SHARES _________________________________________________________________ 8 SHARED VOTING POWER BENEFICIALLY OWNED BY 0 _________________________________________________________________ EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON _________________________________________________________________ 10 SHARED DISPOSITIVE POWER WITH 0 ________________________________________________________________________________ 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 ________________________________________________________________________________ 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0% ________________________________________________________________________________ 14 TYPE OF REPORTING PERSON* PN ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 25243N103 13D Page 6 of 11 Pages ________________________________________________________________________________ 1 NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) HealthCare Partners IV, L.P. ________________________________________________________________________________ 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [_] ________________________________________________________________________________ 3 SEC USE ONLY ________________________________________________________________________________ 4 SOURCE OF FUNDS* N/A ________________________________________________________________________________ 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_] ________________________________________________________________________________ 6 CITIZENSHIP OR PLACE OF ORGANIZATION Delaware ________________________________________________________________________________ 7 SOLE VOTING POWER NUMBER OF SHARES _________________________________________________________________ 8 SHARED VOTING POWER BENEFICIALLY OWNED BY 0 _________________________________________________________________ EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON _________________________________________________________________ 10 SHARED DISPOSITIVE POWER WITH 0 ________________________________________________________________________________ 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 ________________________________________________________________________________ 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0% ________________________________________________________________________________ 14 TYPE OF REPORTING PERSON* PN ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 25243N103 13D Page 7 of 11 Pages ________________________________________________________________________________ 1 NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) James H. Cavanaugh, Ph.D. ________________________________________________________________________________ 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [_] ________________________________________________________________________________ 3 SEC USE ONLY ________________________________________________________________________________ 4 SOURCE OF FUNDS* N/A ________________________________________________________________________________ 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_] ________________________________________________________________________________ 6 CITIZENSHIP OR PLACE OF ORGANIZATION USA ________________________________________________________________________________ 7 SOLE VOTING POWER NUMBER OF SHARES _________________________________________________________________ 8 SHARED VOTING POWER BENEFICIALLY OWNED BY 0 _________________________________________________________________ EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON _________________________________________________________________ 10 SHARED DISPOSITIVE POWER WITH 0 ________________________________________________________________________________ 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 ________________________________________________________________________________ 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0% ________________________________________________________________________________ 14 TYPE OF REPORTING PERSON* IN ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 25243N103 13D Page 8 of 11 Pages ________________________________________________________________________________ 1 NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) Harold R. Werner ________________________________________________________________________________ 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [_] ________________________________________________________________________________ 3 SEC USE ONLY ________________________________________________________________________________ 4 SOURCE OF FUNDS* N/A ________________________________________________________________________________ 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_] ________________________________________________________________________________ 6 CITIZENSHIP OR PLACE OF ORGANIZATION USA ________________________________________________________________________________ 7 SOLE VOTING POWER NUMBER OF SHARES _________________________________________________________________ 8 SHARED VOTING POWER BENEFICIALLY OWNED BY 0 _________________________________________________________________ EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON _________________________________________________________________ 10 SHARED DISPOSITIVE POWER WITH 0 ________________________________________________________________________________ 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 ________________________________________________________________________________ 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0% ________________________________________________________________________________ 14 TYPE OF REPORTING PERSON* IN ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 25243N103 13D Page 9 of 11 Pages ________________________________________________________________________________ 1 NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) William Crouse ________________________________________________________________________________ 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [_] ________________________________________________________________________________ 3 SEC USE ONLY ________________________________________________________________________________ 4 SOURCE OF FUNDS* N/A ________________________________________________________________________________ 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_] ________________________________________________________________________________ 6 CITIZENSHIP OR PLACE OF ORGANIZATION USA ________________________________________________________________________________ 7 SOLE VOTING POWER NUMBER OF SHARES _________________________________________________________________ 8 SHARED VOTING POWER BENEFICIALLY OWNED BY 0 _________________________________________________________________ EACH 9 SOLE DISPOSITIVE POWER REPORTING PERSON _________________________________________________________________ 10 SHARED DISPOSITIVE POWER WITH 0 ________________________________________________________________________________ 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 ________________________________________________________________________________ 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0% ________________________________________________________________________________ 14 TYPE OF REPORTING PERSON* IN ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 25243N103 13D Page 10 of 11 Pages ________________________________________________________________________________ 1 NAME OF REPORTING PERSONS I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY) John W. Littlechild ________________________________________________________________________________ 2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP* (a) [_] (b) [_] ________________________________________________________________________________ 3 SEC USE ONLY ________________________________________________________________________________ 4 SOURCE OF FUNDS* N/A ________________________________________________________________________________ 5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_] ________________________________________________________________________________ 6 CITIZENSHIP OR PLACE OF ORGANIZATION USA ________________________________________________________________________________ 7 SOLE VOTING POWER NUMBER OF 0 SHARES _________________________________________________________________ 8 SHARED VOTING POWER BENEFICIALLY OWNED BY 0 _________________________________________________________________ EACH 9 SOLE DISPOSITIVE POWER REPORTING 0 PERSON _________________________________________________________________ 10 SHARED DISPOSITIVE POWER WITH 0 ________________________________________________________________________________ 11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 0 ________________________________________________________________________________ 12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES* [_] ________________________________________________________________________________ 13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 0% ________________________________________________________________________________ 14 TYPE OF REPORTING PERSON* IN ________________________________________________________________________________ *SEE INSTRUCTIONS BEFORE FILLING OUT! CUSIP No. 25243N103 13D Page 11 of 11 Pages ________________________________________________________________________________ Item 1. Security and Issuer. This statement relates to the common stock, $.01 par value each ("Common Stock") of Diacrin, Inc. (the "Issuer"). The address of the Issuer's principal executive office is Building 96, 13th Street, Charlestown, MA 02120. ________________________________________________________________________________ Item 2. Identity and Background. (a) The name of the reporting persons are HealthCare Ventures II, L.P. ("HCVII"), HealthCare Partners II, L.P. ("HCPII"), HealthCare Ventures III, L.P. ("HCVIII"), HealthCare Partners III, L.P. ("HCPIII"), HealthCare Ventures IV, L.P. ("HCVIV"), HealthCare Partners IV, L.P. ("HCPIV"), Dr. Cavanaugh and Messrs. Werner, Crouse, and Littlechild (HCVII, HCPII, HCVIII, HCPIII, HCVIV, HCPIV, Dr. Cavanaugh and Messrs. Werner, Crouse and Littlechild are hereafter sometimes hereinafter referred to as the "Reporting Persons"). A copy of their agreement in writing to file this statement on behalf of each of them is attached hereto as Exhibit A. HCVII, HCPII, HCVIII and HCPIII, HCVIV and HCPIV are limited partnerships organized and existing under the laws of the State of Delaware. HCPII is the General Partner of HCVII, HCPIII is the General Partner of HCVIII and HCPIV is the General Partner of HCVIV. Dr. Cavanaugh and Messrs.Werner, Crouse and Littlechild are the general partners of HCPII, HCPIII and HCPIV. (b) The business address for HCVII, HCPII, HCVIII, HCPIII, HCVIV and HCPIV, Dr. Cavanaugh and, Messrs. Werner and Crouse is 44 Nassau Street, Princeton, New Jersey 08542. The business address for Mr. Littlechild is One Kendall Square, Building 300, Cambridge, Massachusetts 02339. (c) Each of Dr. Cavanaugh and Messrs. Werner, Crouse and Littlechild are general partners of various venture capital investment funds. The address for Dr. Cavanaugh and Messrs. Werner and Crouse is 44 Nassau Street, Princeton, New Jersey 08542 and the address for Mr. Littlechild is One Kendall square, Building 300, Cambridge, MA 02339. (d) Not Applicable. ________________________________ 1 Dr. Cavanaugh and Messrs Werner, Littlechild and Crouse are the general partners of HCPII, HCPIII and HCPIV, the General Partners of HCVII, HCVIII and HCVIV, the record holders of the Issuer's securities. (e) Not Applicable. (f) Dr. Cavanaugh and Messrs. Werner, Crouse and Littlechild are each individuals who are citizens of the United States. ________________________________________________________________________________ Item 3. Source and Amount of Funds or Other Consideration. Not Applicable ________________________________________________________________________________ Item 4. Purpose of Transaction. (a) Not Applicable. (b) On August 22, 2003, the Issuer and GenVec, Inc. ("GenVec")consummated a merger pursuant to which the Issuer merged with and into GenVec (the "Merger"). In connection with the terms of the Merger, each share of the Issuer's Common Stock was exchanged for 1.5292 shares of GenVec's common stock in a tax-free transaction. On August 22, 2003, the Issuer ceased to have independent existence as a reporting person under the Securities and Exchange Act of 1934 and the Reporting Persons no longer own any shares of Common Stock of the Issuer. (c) Not Applicable. (d) Not Applicable. (e) Not Applicable. (f) Not Applicable. (g) Not Applicable. (h) Not Applicable. (i) Not Applicable. (j) Not Applicable. ________________________________________________________________________________ Item 5. Interest in Securities of the Issuer. (a) The Reporting Persons do not own any shares of the Common Stock of the Issuer. (b) Not Applicable. (c) On August 22, 2003, the 3,196,385 shares of Common Stock of the Issuer owned by HCVII were converted into 4,887,912 shares of Common Stock of GenVec. On August 22, 2003, the 994,078 shares of Common Stock of the Issuer owned by HCVIII were converted into 1,520,144 shares of the Common Stock of GenVec. On August 22, 2003, the 291,922 shares of Common Stock of the Issuer owned by HCVIV were converted into 446,407 shares of Common Stock of GenVec. (d) Not Applicable. (e) The Reporting Persons ceased to be the beneficial owner of more than five percent of the class of securities on August 22, 2003. ________________________________________________________________________________ Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer. Not Applicable. ________________________________________________________________________________ Item 7. Material to be Filed as Exhibits. Exhibit A - Joint Filing Agreement. ________________________________________________________________________________ SIGNATURE After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct. Dated: August 21, 2003 HealthCare Ventures II, L.P., Princeton, New Jersey by its General Partner, HealthCare Partners II, L.P. By: S/Jeffrey Steinberg, Administrative Partner ------------------------------------------- Administrative Partner Dated: August 21, 2003 HealthCare Partners II, L.P. Princeton, New Jersey By: S/Jeffrey Steinberg, Administrative Partner ------------------------------------------- Administrative Partner Dated: August 21, 2003 HealthCare Ventures III, L.P., Princeton, New Jersey by its General Partner, HealthCare Partners III, L.P. By: S/Jeffrey Steinberg, Administrative Partner ------------------------------------------- Administrative Partner Dated: August 21, 2003 HealthCare Partners III, L.P. Princeton, New Jersey By: S/Jeffrey Steinberg, Administrative Partner ------------------------------------------- Administrative Partner Dated: August 21, 2003 HealthCare Ventures IV, L.P., Princeton, New Jersey by its General Partner, HealthCare Partners IV, L.P. By: S/Jeffrey Steinberg, Administrative Partner ------------------------------------------- Administrative Partner Dated: August 21, 2003 HealthCare Partners IV, L.P. Princeton, New Jersey By: S/Jeffrey Steinberg, Administrative Partner ------------------------------------------- Administrative Partner Dated: August 21, 2003 By: S/Jeffrey Steinberg, Attorney-in-Fact Princeton, New Jersey ------------------------------------------- James H. Cavanaugh, Ph.D. Dated: August 21, 2003 By: S/Jeffrey Steinberg, Attorney-in-Fact Princeton, New Jersey ------------------------------------------- Harold R. Werner Dated: August 21, 2003 By: S/Jeffrey Steinberg, Attorney-in-Fact Princeton, New Jersey ------------------------------------------- William Crouse Dated: August 21, 2003 By: S/Jeffrey Steinberg, Attorney-in-Fact Cambridge, Massachusetts ------------------------------------------- John W. Littlechild EXHIBIT A AGREEMENT JOINT FILING OF SCHEDULE 13D The undersigned hereby consent to the joint filing by any of them of a Statement on Schedule 13D and any amendments thereto, whether heretofore or hereafter filed, relating to the securities of Diacrin, Inc., and affirm that this Schedule 13D is being filed on behalf of each of the undersigned. Dated: August 21, 2003 HealthCare Ventures II, L.P., Princeton, New Jersey by its General Partner, HealthCare Partners II, L.P. By: S/Jeffrey Steinberg, Administrative Partner ------------------------------------------- Administrative Partner Dated: August 21, 2003 HealthCare Partners II, L.P. Princeton, New Jersey By: S/Jeffrey Steinberg, Administrative Partner ------------------------------------------- Administrative Partner Dated: August 21, 2003 HealthCare Ventures III, L.P., Princeton, New Jersey by its General Partner, HealthCare Partners III, L.P. By: S/Jeffrey Steinberg, Administrative Partner ------------------------------------------- Administrative Partner Dated: August 21, 2003 HealthCare Partners III, L.P. Princeton, New Jersey By: S/Jeffrey Steinberg, Administrative Partner ------------------------------------------- Administrative Partner Dated: August 21, 2003 HealthCare Ventures IV, L.P., Princeton, New Jersey by its General Partner, HealthCare Partners IV, L.P. By: S/Jeffrey Steinberg, Administrative Partner ------------------------------------------- Administrative Partner Dated: August 21, 2003 HealthCare Partners IV, L.P. Princeton, New Jersey By: S/Jeffrey Steinberg, Administrative Partner ------------------------------------------- Administrative Partner Dated: August 21, 2003 By: S/Jeffrey Steinberg, Attorney-in-Fact Princeton, New Jersey ------------------------------------------- James H. Cavanaugh, Ph.D. Dated: August 21, 2003 By: S/Jeffrey Steinberg, Attorney-in-Fact Princeton, New Jersey ------------------------------------------- Harold R. Werner Dated: August 21, 2003 By: S/Jeffrey Steinberg, Attorney-in-Fact Princeton, New Jersey ------------------------------------------- William Crouse Dated: August 21, 2003 By: S/Jeffrey Steinberg, Attorney-in-Fact Cambridge, Massachusetts ------------------------------------------- John W. Littlechild Attention. Intentional misstatements or omissions of fact constitute federal criminal violations (see 18 U.S.C. 1001).