<PAGE>
- --------------------------------------------------------------------------------
CUSIP NO. 759916 10 9 13D Page 1 of 8 Pages
- --------------------------------------------------------------------------------
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549
SCHEDULE 13D
(RULE 13d-101)
INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT TO 13D-1(a)
AND AMENDMENTS THERETO FILED PURSUANT TO 13d-2(a)
(AMENDMENT NO. 1)(1)
REPLIGEN CORP.
- --------------------------------------------------------------------------------
(Name of Issuer)
COMMON STOCK
- --------------------------------------------------------------------------------
(Title of Class of Securities)
759916 10 9
- --------------------------------------------------------------------------------
(CUSIP Number)
Hope Flack
BVF Partners L.P.
227 West Monroe Street, Suite 4800
Chicago, Illinois 60606
(312) 263-7777
- --------------------------------------------------------------------------------
(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)
May 24, 1999
- --------------------------------------------------------------------------------
(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 which is the subject of this Schedule 13D, and is filing
this schedule because of Rule 13d-1(b)(3) or (4), check the following box / /.
NOTE: Six copies of this statement, including all exhibits, should be filed
with the Commission. SEE Rule 13d-1(a) for other parties to whom copies are to
be sent.
(1) 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).
(Continued on following pages)
(Page 1 of 8 Pages)
<PAGE>
- --------------------------------------------------------------------------------
CUSIP No. 759916 10 9 13G Page 2 of 8 Pages
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSON:
BIOTECHNOLOGY VALUE FUND, L.P.
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY):
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) /X/ (b) / /
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
DELAWARE
- --------------------------------------------------------------------------------
NUMBER 5 SOLE VOTING POWER
OF 0
SHARES -------------------------------------------------------------
BENEFICIALLY 6 SHARED VOTING POWER
OWNED BY EACH 917,500
REPORTING -------------------------------------------------------------
PERSON 7 SOLE DISPOSITIVE POWER
WITH 0
-------------------------------------------------------------
8 SHARED DISPOSITIVE POWER
917,500
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
917,500
- --------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* / /
- --------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
4.9%
- --------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
PN
- --------------------------------------------------------------------------------
* SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
- --------------------------------------------------------------------------------
CUSIP No. 759916 10 9 13D Page 3 of 8 Pages
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSON:
BIOTECHNOLOGY VENTURE PARTNERS L.P.
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY):
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) /X/ (b) / /
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
DELAWARE
- --------------------------------------------------------------------------------
NUMBER 5 SOLE VOTING POWER
OF 0
SHARES -------------------------------------------------------------
BENEFICIALLY 6 SHARED VOTING POWER
OWNED BY EACH 342,500
REPORTING -------------------------------------------------------------
PERSON 7 SOLE DISPOSITIVE POWER
WITH 0
-------------------------------------------------------------
8 SHARED DISPOSITIVE POWER
342,500
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
342,500
- --------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* / /
- --------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
1.8%
- --------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
PN
- --------------------------------------------------------------------------------
* SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
- --------------------------------------------------------------------------------
CUSIP No. 759916 10 9 13D Page 4 of 8 Pages
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSON:
BVF PARTNERS L.P.
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY):
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) /X/ (b) / /
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
DELAWARE
- --------------------------------------------------------------------------------
NUMBER 5 SOLE VOTING POWER
OF 0
SHARES -------------------------------------------------------------
BENEFICIALLY 6 SHARED VOTING POWER
OWNED BY EACH 2,086,250
REPORTING -------------------------------------------------------------
PERSON 7 SOLE DISPOSITIVE POWER
WITH 0
-------------------------------------------------------------
8 SHARED DISPOSITIVE POWER
2,086,250
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
2,086,250
- --------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* / /
- --------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
11.2%
- --------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
PN
- --------------------------------------------------------------------------------
* SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
- --------------------------------------------------------------------------------
CUSIP No. 759916 10 9 13D Page 5 of 8 Pages
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSONS
BVF INC.
I.R.S. IDENTIFICATION NO. OF ABOVE PERSONS (ENTITIES ONLY)
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) /X/ (b) / /
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 CITIZENSHIP OR PLACE OF ORGANIZATION
DELAWARE
- --------------------------------------------------------------------------------
NUMBER 5 SOLE VOTING POWER
OF 0
SHARES -------------------------------------------------------------
BENEFICIALLY 6 SHARED VOTING POWER
OWNED BY EACH 2,086,250
REPORTING -------------------------------------------------------------
PERSON 7 SOLE DISPOSITIVE POWER
WITH 0
-------------------------------------------------------------
8 SHARED DISPOSITIVE POWER
2,086,250
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
2,086,250
- --------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* / /
- --------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
11.2%
- --------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
IA, CO
- --------------------------------------------------------------------------------
* SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
- --------------------------------------------------------------------------------
CUSIP No. 759916 10 9 13D Page 6 of 8 Pages
- --------------------------------------------------------------------------------
Amendment No. 1 (the "Amendment") to the Statement on Schedule 13D, dated
September 8, 1998 (as so amended, the "Statement"), filed with the Securities
and Exchange Commission on behalf of Biotechnology Value Fund, L.P., a Delaware
limited partnership ("BVF"), BVF Biotechnology Venture Partners L.P., a Delaware
limited partnership ("Venture"), BVF Partners L.P., a Delaware limited
partnership ("Partners"), and BVF Inc., a Delaware corporation ("BVF Inc." and,
together with BVF, Venture and Partners, the "Reporting Persons") with respect
to the Common Stock (the "Stock") of Repligen Corporation, a Delaware
corporation ("RGEN").
Item 3 is hereby amended to read in its entirety as follows:
ITEM 3. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION.
Since March 25, 1999, Partners, in its capacity as general partner of BVF,
has sold on behalf of such limited partnership an aggregate number of 45,000
shares of the Stock for an aggregate consideration of $129,370.67, utilizing
funds provided by BVF from its working capital pursuant to the terms of its
limited partnership agreement with Partners. Also, Partners, in its capacity as
general partner of Venture, has sold on behalf of such limited partnership an
aggregate number of 70,000 shares of the Stock for an aggregate consideration of
$198,723.29, utilizing funds provided by Venture from its working capital
pursuant to the terms of its limited partnership agreement with Partners. In
addition, Partners, in its capacity as investment manager with respect to
certain Accounts, has sold on behalf of such Accounts an aggregate number of
205,000 shares of the Stock for an aggregate consideration of $591,066.66. The
Accounts on whose behalf Partners owns shares of the Stock are Investment 10
L.L.C., an Illinois limited liability company ("ILL10") and Biotechnology Value
Fund, Ltd., a Cayman Islands Corporation ("BVF Ltd."). ILL10 and BVF Ltd. are
collectively referred to herein as the "Accounts." The Accounts specialize in
holding biotechnology stocks for investment purposes and the business address of
each is BVF Partners L.P., 227 West Monroe Drive, Suite 4800, Chicago, Illinois
60606.
Item 5 is hereby amended to read in its entirety as follows:
ITEM 5. INTEREST IN SECURITIES OF THE ISSUER.
(a) BVF beneficially owns 655,000 shares of the Stock and 262,500
Warrants, Venture beneficially owns 230,000 shares of the Stock and 112,500
Warrants, Partners beneficially owns 1,500,000 shares of the Stock and
656,250 Warrants, and BVF Inc. beneficially owns 1,500,000 shares of the
Stock and 656,250 Warrants, approximately 4.9%, 1.8%, 11.2% and 11.2%,
respectively, of the aggregate number of shares outstanding as of January 31,
1999 (as reported in RGEN's most recent quarterly statement on Form 10-Q).
Pursuant to Rule 13d-3(d)(1)(i) under the Securities Exchange Act of 1934,
the percent of class calculated for each Reporting Person assumes the full
exercise of all Warrants beneficially owned by such Reporting Person.
<PAGE>
- --------------------------------------------------------------------------------
CUSIP No. 759916 10 9 13D Page 7 of 8 Pages
- --------------------------------------------------------------------------------
(b) BVF shares voting and dispositive power over the 655,000 shares of
the Stock and 262,500 Warrants it beneficially owns with Partners. Venture
shares voting and dispositive power over the 230,000 shares of the Stock and the
112,500 Warrants it beneficially owns with Partners. Partners and BVF Inc.
share voting and dispositive power over the 1,500,000 shares of the Stock and
656,250 Warrants they beneficially own with, in addition to BVF and Venture, the
Accounts on whose behalf Partners, as investment manager, purchased such shares.
(c) Exhibit B attached hereto contains information as to all transactions
in the Stock by the Reporting Persons during the last 60 days. All such
transactions were made for cash in open market, over-the-counter transactions.
No other transactions in the Stock have been effected by the Reporting Persons
during the last 60 days.
(d) The Accounts are entitled to receive dividends and any sale proceeds
with respect to the Stock in proportion to their respective ownership interests
therein.
Item 7 is hereby amended to read in its entirety as follows:
ITEM 7. MATERIAL TO BE FILED AS EXHIBITS.
Exhibit A - Agreement Regarding Joint Filing
Exhibit B - Transactions in the Stock by the Reporting Persons during the
last 60 days.
<PAGE>
- --------------------------------------------------------------------------------
CUSIP No. 759916 10 9 13D Page 8 of 8 Pages
- --------------------------------------------------------------------------------
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: May 28, 1999
BIOTECHNOLOGY VALUE FUND, L.P.
By: BVF Partners L.P., its general partner
By: BVF Inc., its general partner
By: /s/ Mark N. Lampert
-------------------
Mark N. Lampert
President
BIOTECHNOLOGY VENTURE PARTNERS, L.P.
By: BVF Partners L.P., its general partner
By: BVF Inc., its general partner
By: /s/ Mark N. Lampert
-------------------
Mark N. Lampert
President
BVF PARTNERS L.P.
By: BVF Inc., its general partner
By: /s/ Mark N. Lampert
-------------------
Mark N. Lampert
President
BVF INC.
By: /s/ Mark N. Lampert
-------------------
Mark N. Lampert
President
<PAGE>
EXHIBIT A
AGREEMENT REGARDING JOINT FILING
The undersigned, Biotechnology Value Fund, L.P., a Delaware limited
partnership, Biotechnology Venture Partners, L.P., a Delaware limited
partnership and BVF Partners L.P., a Delaware limited partnership, and BVF Inc.,
a Delaware corporation, hereby agree and acknowledge that the information
required by Schedule 13D, to which this Agreement is attached as an exhibit, is
filed on behalf of each of them. The undersigned further agree that any
amendments or supplements thereto shall also be filed on behalf of each of them.
Dated: May 28, 1999
BIOTECHNOLOGY VALUE FUND, L.P.
By: BVF Partners L.P., its general partner
By: BVF Inc., its general partner
By: /s/ Mark N. Lampert
-------------------
Mark N. Lampert
President
BIOTECHNOLOGY VENTURE PARTNERS, L.P.
By: BVF Partners L.P., its general partner
By: BVF Inc., its general partner
By: /s/ Mark N. Lampert
-------------------
Mark N. Lampert
President
BVF PARTNERS L.P.
By: BVF Inc., its general partner
By: /s/ Mark N. Lampert
-------------------
Mark N. Lampert
President
BVF INC.
By: /s/ Mark N. Lampert
-------------------
Mark N. Lampert
President
<PAGE>
EXHIBIT B
TRANSACTIONS IN THE STOCK BY THE REPORTING PERSONS
DURING THE PAST SIXTY DAYS
<TABLE>
<CAPTION>
For the
Trade Date By Account of Quantity Price per Share Type of Trade Broker
- --------------------------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C>
05/03/99 BVF Partners (13,000) $2.8750 Sale JONE
- --------------------------------------------------------------------------------------------------
05/03/99 BVF Ltd. Partners (5,000) $3.0000 Sale HRZG
- --------------------------------------------------------------------------------------------------
05/04/99 BVF Partners (16,000) $2.8750 Sale JONE
- --------------------------------------------------------------------------------------------------
05/04/99 BVF Ltd. Partners (16,000) $2.8750 Sale JONE
- --------------------------------------------------------------------------------------------------
05/05/99 ILL10 Partners (10,000) $2.9375 Sale HRZG
- --------------------------------------------------------------------------------------------------
05/14/99 BVF Partners (13,000) $2.8750 Sale HRZG
- --------------------------------------------------------------------------------------------------
05/14/99 BVF Ltd. Partners (12,000) $2.8750 Sale HRZG
- --------------------------------------------------------------------------------------------------
05/14/99 Venture Partners (70,000) $2.8750 Sale MLCO
- --------------------------------------------------------------------------------------------------
05/17/99 ILL10 Partners (35,000) $2.9464 Sale HRZG
- --------------------------------------------------------------------------------------------------
05/24/99 ILL10 Partners (100,000) $2.8750 Sale MLCO
- --------------------------------------------------------------------------------------------------
05/24/99 ILL10 Partners (25,000) $2.9375 Sale HRZG
- --------------------------------------------------------------------------------------------------
05/26/99 BVF Partners (3,000) $2.8750 Sale HRZG
- --------------------------------------------------------------------------------------------------
05/26/99 BVF Ltd. Partners (2,000) $2.8750 Sale HRZG
- --------------------------------------------------------------------------------------------------
</TABLE>
HRZG = Herzog, Heine & Geduld
JONE = Jones & Co.
MLCO = Merrill Lynch & Co.
