<PAGE>
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549
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SCHEDULE 13D
(RULE 13d-101)
UNDER THE SECURITIES EXCHANGE ACT OF 1934
(AMENDMENT NO. 1)/1/
ADVANCED MAGNETICS, INC.
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(Name of Issuer)
Common Stock
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(Title of Class of Securities)
00753 P 103
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(CUSIP Number)
Hope Flack
BVF Partners L.P.
333 West Wacker Drive, Suite 1600
Chicago, Illinois 60606
(312) 263-7777
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(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)
April 28, 1997
--------------
(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.
(Continued on following pages)
(Page 1 of 7 Pages)
- --------------------------
/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).
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CUSIP NO. 00753 P 103 13D PAGE 2 OF 7 PAGES
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- ------------------------------------------------------------------------------
NAME OF REPORTING PERSONS
1 S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS
BIOTECHNOLOGY VALUE FUND, L.P.
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CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [X]
(b) [_]
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SEC USE ONLY
3
- ------------------------------------------------------------------------------
4 SOURCE OF FUNDS*
WC
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5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS
REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_]
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6 CITIZENSHIP OR PLACE OF ORGANIZATION
DELAWARE
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SOLE VOTING POWER
7
NUMBER OF -0-
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 8
232,620
OWNED BY
-----------------------------------------------------------
REPORTING SOLE DISPOSITIVE POWER
9
PERSON -0-
WITH -----------------------------------------------------------
SHARED DISPOSITIVE POWER
10
232,620
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AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
11
232,620
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CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11 EXCLUDES CERTAIN SHARES* [_]
12
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11
13
3.4%
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TYPE OF REPORTING PERSON*
14
PN
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*SEE INSTRUCTION BEFORE FILLING OUT!
<PAGE>
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CUSIP NO. 00753 P 103 13D PAGE 3 OF 7 PAGES
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NAME OF REPORTING PERSONS
1 S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS
BVF PARTNERS L.P.
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CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [X]
(b) [_]
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SEC USE ONLY
3
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4 SOURCE OF FUNDS*
OO
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5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS
REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_]
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6 CITIZENSHIP OR PLACE OF ORGANIZATION
DELAWARE
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SOLE VOTING POWER
7
NUMBER OF -0-
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 8
474,200
OWNED BY
-----------------------------------------------------------
REPORTING SOLE DISPOSITIVE POWER
9
PERSON -0-
WITH -----------------------------------------------------------
SHARED DISPOSITIVE POWER
10
474,200
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
11
474,200
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11 EXCLUDES CERTAIN SHARES* [_]
12
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11
13
7.0%
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TYPE OF REPORTING PERSON*
14
PN
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*SEE INSTRUCTION BEFORE FILLING OUT!
<PAGE>
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CUSIP NO. 00753 P 103 13D PAGE 4 OF 7 PAGES
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- ------------------------------------------------------------------------------
NAME OF REPORTING PERSONS
1 S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS
BVF INC.
- ------------------------------------------------------------------------------
CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
2 (a) [X]
(b) [_]
- ------------------------------------------------------------------------------
SEC USE ONLY
3
- ------------------------------------------------------------------------------
4 SOURCE OF FUNDS*
WC, OO
- ------------------------------------------------------------------------------
5 CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDING IS
REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e) [_]
- ------------------------------------------------------------------------------
6 CITIZENSHIP OR PLACE OF ORGANIZATION
DELAWARE
- ------------------------------------------------------------------------------
SOLE VOTING POWER
7
NUMBER OF -0-
SHARES -----------------------------------------------------------
SHARED VOTING POWER
BENEFICIALLY 8
474,200
OWNED BY
-----------------------------------------------------------
REPORTING SOLE DISPOSITIVE POWER
9
PERSON -0-
WITH -----------------------------------------------------------
SHARED DISPOSITIVE POWER
10
474,200
- ------------------------------------------------------------------------------
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
11
474,200
- ------------------------------------------------------------------------------
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW 11 EXCLUDES CERTAIN SHARES* [_]
12
- ------------------------------------------------------------------------------
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11
13
7.0%
- ------------------------------------------------------------------------------
TYPE OF REPORTING PERSON*
14
IA, CO
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*SEE INSTRUCTION BEFORE FILLING OUT!
<PAGE>
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| CUSIP NO. 00753 P 103 | 13D | Page 5 of 7 Pages |
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This Amendment No. 1 (this "Amendment") relates to the Statement on
Schedule 13D (the "Statement") dated October 30, 1996, 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 $0.10 per share (the "Stock"), of Advanced Magnetics,
Inc. ("Advanced Magnetics").
Item 3 is hereby amended to read in its entirety as follows:
ITEM 3. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION.
Since March 1, 1997, Partners, in its capacity as general partner of BVF,
has purchased on behalf of such limited partnership an aggregate number of
13,800 shares of the Stock for an aggregate consideration of $163,706.13,
utilizing funds provided by BVF from its working capital pursuant to the terms
of its limited partnership agreement with Partners.
Item 5 is hereby amended to read in its entirety as follows:
ITEM 5. INTEREST IN SECURITIES OF THE ISSUER.
(a) BVF beneficially owns 232,620 shares of the Stock, Partners
beneficially owns 474,200 shares of the Stock, and BVF Inc. beneficially owns
474,200 shares of the Stock, approximately 3.4%, 7.0% and 7.0%, respectively, of
the aggregate number of shares outstanding as of May 16, 1997.
(b) BVF shares voting and dispositive power over the 232,620 shares of the
Stock it beneficially owns with Partners. Partners and BVF Inc. share voting
and dispositive power over the 474,200 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 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 c/o 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 during the past 60 days. All such
transactions were made for
<PAGE>
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| CUSIP NO. 00753 P 103 | 13D | Page 6 of 7 Pages |
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cash in open market, over-the-counter transactions. No other transactions in the
Stock have been effected by the Reporting Persons during the past 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.
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| CUSIP NO. 00753 P 103 | 13D | Page 7 of 7 Pages |
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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 16, 1997
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: May 16, 1997
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
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DURING THE LAST 60 DAYS
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<TABLE>
<CAPTION>
Settlement For the Price per
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Date By Account of Quantity Share Type of Trade Broker
---- -- ---------- -------- ----- ------------- ------
======================================================================================
<S> <C> <C> <C> <C> <C> <C>
04/28/97 Partners BVF 5,000 $11.5000 Purchase DAKN
05/06/97 Partners BVF 2,500 $11.6563 Purchase MIST
05/16/97 Partners BVF 6,300 $12.1250 Purchase DAKN
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</TABLE>
DAKN = Dakin Securities
MIST = Mr. Stock
