<PAGE>
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)
NEUROGEN CORPORATION
--------------------
(Name of Issuer)
COMMON STOCK
------------
(Title of Class of Securities)
64124E 10 6
-----------
(CUSIP Number)
Hope Flack
BVF Partners L.P.
333 West Wacker Drive, Suite 1600
Chicago, Illinois 60606
(312) 263-7777
-----------------------------------------
(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)
November 23, 1998
-----------------
(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).
<PAGE>
- ------------------------------------ -----------------------------------
CUSIP NO. 671040 10 3 13D Page 2 of 7 Pages
- ------------------------------------ -----------------------------------
(Page 2 of 7 Pages)
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
BIOTECHNOLOGY VALUE FUND, L.P.
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) /X/ (b) / /
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 SOURCE OF FUNDS*
WC
- --------------------------------------------------------------------------------
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
-0-
--------------------------------------------------------------
8 SHARED VOTING POWER
NUMBER OF 787,920
SHARES --------------------------------------------------------------
BENEFICIALLY 9 SOLE DISPOSITIVE POWER
OWNED BY -0-
EACH --------------------------------------------------------------
REPORTING 10 SHARED DISPOSITIVE POWER
PERSON WITH 787,920
- --------------------------------------------------------------------------------
11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
787,920
- --------------------------------------------------------------------------------
12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* / /
- --------------------------------------------------------------------------------
13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
5.3%
- --------------------------------------------------------------------------------
14 TYPE OF REPORTING PERSON*
PN
- --------------------------------------------------------------------------------
* SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
- ------------------------------------ -----------------------------------
CUSIP NO. 671040 10 3 13D Page 3 of 7 Pages
- ------------------------------------ -----------------------------------
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
BVF PARTNERS L.P.
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) /X/ (b) / /
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 SOURCE OF FUNDS*
OO
- --------------------------------------------------------------------------------
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
-0-
--------------------------------------------------------------
8 SHARED VOTING POWER
NUMBER OF 1,653,306
SHARES --------------------------------------------------------------
BENEFICIALLY 9 SOLE DISPOSITIVE POWER
OWNED BY -0-
EACH --------------------------------------------------------------
REPORTING 10 SHARED DISPOSITIVE POWER
PERSON WITH 1,653,306
- --------------------------------------------------------------------------------
11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,653,306
- --------------------------------------------------------------------------------
12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* / /
- --------------------------------------------------------------------------------
13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
11.2%
- --------------------------------------------------------------------------------
14 TYPE OF REPORTING PERSON*
PN
- --------------------------------------------------------------------------------
* SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
- ------------------------------------ -----------------------------------
CUSIP NO. 671040 10 3 13D Page 4 of 7 Pages
- ------------------------------------ -----------------------------------
- --------------------------------------------------------------------------------
1 NAME OF REPORTING PERSONS
I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
BVF INC.
- --------------------------------------------------------------------------------
2 CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) /X/ (b) / /
- --------------------------------------------------------------------------------
3 SEC USE ONLY
- --------------------------------------------------------------------------------
4 SOURCE OF FUNDS*
WC, OO
- --------------------------------------------------------------------------------
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
-0-
--------------------------------------------------------------
8 SHARED VOTING POWER
NUMBER OF 1,653,306
SHARES --------------------------------------------------------------
BENEFICIALLY 9 SOLE DISPOSITIVE POWER
OWNED BY -0-
EACH --------------------------------------------------------------
REPORTING 10 SHARED DISPOSITIVE POWER
PERSON WITH 1,653,306
- --------------------------------------------------------------------------------
11 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,653,306
- --------------------------------------------------------------------------------
12 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
CERTAIN SHARES* / /
- --------------------------------------------------------------------------------
13 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
11.2%
- --------------------------------------------------------------------------------
14 TYPE OF REPORTING PERSON*
IA, CO
- --------------------------------------------------------------------------------
* SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
- ------------------------------------ -----------------------------------
CUSIP NO. 671040 10 3 13D Page 5 of 7 Pages
- ------------------------------------ -----------------------------------
This Amendment No. 1 (the "Amendment") relates to the Statement on Schedule
13D, dated September 8, 1997 (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 Partners L.P., a Delaware limited
partnership ("Partners"), and BVF Inc., a Delaware corporation ("BVF Inc." and,
together with BVF and Partners, the "Reporting Persons") with respect to the
Common Stock, par value $.025 per share (the "Stock"), of Neurogen Corporation
("Neurogen"), a Delaware corporation.
Item 3 is hereby amended to read in its entirety as follows:
ITEM 3. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION.
Since its most recent filing on Schedule 13D, Partners, in its capacity as
general partner of BVF, has sold on behalf of such limited partnership an
aggregate number of 130,600 shares of the Stock for an aggregate consideration
of $2,228,927.64. In addition, Partners, in its capacity as investment manager
with respect to certain managed accounts, has sold on behalf of such managed
accounts an aggregate number of 135,000 shares of the Stock for an aggregate
consideration of $2,278,125.00.
Item 5 is hereby amended to read in its entirety as follows:
ITEM 5. INTEREST IN SECURITIES OF THE ISSUER.
(a) BVF beneficially owns 787,920 shares of the Stock, Partners
beneficially owns 1,653,306 shares of the Stock, and BVF Inc. beneficially owns
1,653,306 shares of the Stock, approximately 5.3%, 11.2% and 11.2%,
respectively, of the aggregate number of shares outstanding as of November 13,
1998 (as reported in Neurogen's most recent quarterly statement on Form 10-Q).
(b) BVF shares voting and dispositive power over the 787,920 shares of
the Stock it beneficially owns with Partners. Partners and BVF Inc. share
voting and dispositive power over the 1,653,306 shares of the Stock they
beneficially own with, in addition to BVF, the managed accounts on whose behalf
Partners, as investment manager, purchased such shares. The managed accounts on
whose behalf Partners owns shares of the Stock are Investment 10 L.L.C., an
Illinois limited liability company ("ILL10"), Palamundo, L.D.C., a limited
duration company organized under the laws of the Cayman Islands ("Palamundo"),
ZPG
<PAGE>
- ------------------------------------ -----------------------------------
CUSIP NO. 671040 10 3 13D Page 6 of 7 Pages
- ------------------------------------ -----------------------------------
Securities, L.L.C., a New York limited liability company ("ZPG") and
Biotechnology Value Fund, Ltd., a Cayman Islands Corporation ("BVF Ltd.").
ILL10, Palamundo, ZPG 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., 333
West Wacker Drive, Suite 1600, Chicago, Illinois 60606.
(c) Exhibit B attached hereto contains information as to all transactions
in the Stock by the Reporting Persons since the most recent filing on Schedule
13D. 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 since the most recent filing on Schedule 13D.
(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 since the
most recent filing on Schedule 13D.
<PAGE>
- ------------------------------------ -----------------------------------
CUSIP NO. 671040 10 3 13D Page 7 of 7 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: November 24, 1998.
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
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, and BVF Partners L.P., a Delaware limited partnership, and BVF
Inc., a Delaware corporation, hereby agree and acknowledge that the Amendment
containing 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 further amendments or supplements thereto shall also be
filed on behalf of each of them.
Dated: November 24, 1998.
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
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 PRICE PER TYPE OF
TRADE DATE BY ACCOUNT OF QUANTITY SHARE TRADE BROKER
- --------------------------------------------------------------------------------
<S> <C> <C> <C> <C> <C> <C>
11/23/98 BVF Partners (65,000) $16.8750 Sale JONE
- --------------------------------------------------------------------------------
11/23/98 ILL10 Partners (31,000) $16.8750 Sale JONE
- --------------------------------------------------------------------------------
11/23/98 PAL Partners (28,000) $16.8750 Sale JONE
- --------------------------------------------------------------------------------
11/23/98 ZPG Partners (16,000) $16.8750 Sale JONE
- --------------------------------------------------------------------------------
11/23/98 BVF Ltd. Partners (60,000) $16.8750 Sale JONE
- --------------------------------------------------------------------------------
11/23/98 BVF Partners (65,600) $17.2569 Sale INET
- --------------------------------------------------------------------------------
</TABLE>
INET = Instinet
JONE = Jones and Associates
