<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. 3)(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)
March 19, 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.
(Continued on following pages)
(Page 1 of 7 Pages)
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(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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(1) Names of Reporting Persons. S.S. or I.R.S. Identification Nos. of Above
Persons
BIOTECHNOLOGY VALUE FUND, L.P.
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(2) Check the Appropriate Box if a Member (a) /X/
of a Group* (b) / /
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(3) SEC Use Only
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(4) Source of Funds*
WC
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(5) Check if Disclosure of Legal Proceedings 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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Number of Shares (7) Sole Voting
Beneficially Owned Power -0-
by Each Reporting --------------------------------------------------
Person With (8) Shared Voting
Power 353,600
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(9) Sole Dispositive
Power -0-
--------------------------------------------------
(10) Shared Dispositive
Power 353,600
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(11) Aggregate Amount Beneficially Owned by Each Reporting Person
353,600
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(12) Check if the Aggregate Amount in Row (11) Excludes Certain Shares*
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(13) Percent of Class Represented by Amount in Row (11)
5.3%
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(14) Type of Reporting Person*
PN
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* SEE INSTRUCTIONS BEFORE FILLING OUT!
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CUSIP No. 00753 P 103 13D Page 3 of 7 Pages
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(1) Names of Reporting Persons. S.S. or I.R.S. Identification Nos. of Above
Persons
BVF PARTNERS L.P.
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(2) Check the Appropriate Box if a Member (a) /X/
of a Group* (b) / /
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(3) SEC Use Only
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(4) Source of Funds*
OO
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(5) Check if Disclosure of Legal Proceedings 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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Number of Shares (7) Sole Voting
Beneficially Owned Power -0-
by Each Reporting --------------------------------------------------
Person With (8) Shared Voting
Power 723,635
--------------------------------------------------
(9) Sole Dispositive
Power -0-
--------------------------------------------------
(10) Shared Dispositive
Power 723,635
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(11) Aggregate Amount Beneficially Owned by Each Reporting Person
723,635
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(12) Check if the Aggregate Amount in Row (11) Excludes Certain Shares*
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(13) Percent of Class Represented by Amount in Row (11)
10.8%
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(14) Type of Reporting Person*
PN
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* SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
CUSIP No. 00753 P 103 13D Page 4 of 7 Pages
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(1) Names of Reporting Persons. S.S. or I.R.S. Identification Nos. of Above
Persons
BVF INC.
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(2) Check the Appropriate Box if a Member (a) /X/
of a Group* (b) / /
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(3) SEC Use Only
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(4) Source of Funds*
WC, OO
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(5) Check if Disclosure of Legal Proceedings 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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Number of Shares (7) Sole Voting
Beneficially Owned Power -0-
by Each Reporting --------------------------------------------------
Person With (8) Shared Voting
Power 723,635
--------------------------------------------------
(9) Sole Dispositive
Power -0-
--------------------------------------------------
(10) Shared Dispositive
Power 723,635
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(11) Aggregate Amount Beneficially Owned by Each Reporting Person
723,635
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(12) Check if the Aggregate Amount in Row (11) Excludes Certain Shares*
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(13) Percent of Class Represented by Amount in Row (11)
10.8%
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(14) Type of Reporting Person*
IA, CO
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* SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
CUSIP No. 00753 P 103 13D Page 5 of 7 Pages
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This Amendment No. 3 (this "Amendment") relates to the Statement on
Schedule 13D, dated October 30, 1996, as amended by Amendment No. 2, dated
December 24, 1997, and Amendment No. 1, dated April 18, 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 $0.01 per
share (the "Stock"), of Advanced Magnetics, Inc. ("Advanced Magnetics"). The
principal executive office of Advanced Magnetics is located at 725 Concord
Ave, Cambridge, MA 02138.
Item 3 is hereby amended to read in its entirety as follows:
ITEM 3. SOURCE AND AMOUNT OF FUNDS OR OTHER CONSIDERATION.
Since January 17, 1998, Partners, in its capacity as general partner of
BVF, has purchased on behalf of such limited partnership an aggregate number
of 17,200 shares of the Stock for an aggregate consideration of $225,193.25,
utilizing funds provided by BVF 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
managed accounts, has purchased on behalf of such managed accounts an
aggregate number of 37,700 shares of the Stock for an aggregate consideration
of $483,645.91, utilizing funds under management by Partners pursuant to an
investment management agreement between Partners and such managed accounts.
Item 5 is hereby amended to read in its entirety as follows:
ITEM 5. INTEREST IN SECURITIES OF THE ISSUER.
(a) BVF beneficially owns 353,600 shares of the Stock, Partners
beneficially owns 723,635 shares of the Stock, and BVF Inc. beneficially owns
723,635 shares of the Stock, approximately 5.3%, 10.8% and 10.8%, respectively,
of the aggregate number of shares outstanding (as reported in Advanced Magnetics
most recent quarterly statement on Form 10-Q).
(b) BVF shares voting and dispositive power over the 353,600 shares of
the Stock it beneficially owns with Partners. Partners and BVF Inc. share
voting and dispositive power over the 723,635 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
<PAGE>
CUSIP No. 00753 P 103 13D Page 6 of 7 Pages
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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 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 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: March 30, 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: March 30, 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 LAST 60 DAYS
<TABLE>
<CAPTION>
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SETTLEMENT FOR THE PRICE PER TYPE OF
DATE BY ACCOUNT OF QUANTITY SHARE TRADE BROKER
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<S> <C> <C> <C> <C> <C> <C>
01/30/98 Partners BVF Ltd. 3,000 $9.9688 Purchase DAKN
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03/06/98 Partners BVF Ltd. 9,600 $12.9830 Purchase DAKN
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03/09/98 Partners BVF 5,000 $12.9873 Purchase HJCO
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03/09/98 Partners ILL10 900 $12.9873 Purchase HJCO
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03/09/98 Partners PAL 600 $12.9873 Purchase HJCO
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03/09/98 Partners ZPG 500 $12.9873 Purchase HJCO
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03/09/98 Partners BVF Ltd. 3,000 $12.9873 Purchase HJCO
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03/11/98 Partners BVF Ltd. 11,300 $13.0000 Purchase HJCO
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03/13/98 Partners BVF 7,200 $13.0000 Purchase HJCO
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03/13/98 Partners BVF Ltd. 2,000 $13.0000 Purchase HJCO
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03/16/98 Partners BVF Ltd. 1,800 $12.9720 Purchase HJCO
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03/19/98 Partners BVF 5,000 $13.1250 Purchase HJCO
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03/19/98 Partners BVF Ltd. 5,000 $13.1250 Purchase HJCO
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</TABLE>
DAKN = Dakin Securities
HJCO = H.J. Meyers
