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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549
SCHEDULE 13G
(RULE 13d-102)
INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
TO RULES 13d-1(b) (c) AND (d) AND AMENDMENTS THERETO FILED
PURSUANT TO 13d-2(b)
(AMENDMENT No. 1 )(1)
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IMMUNOGEN, INC.
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(Name of Issuer)
COMMON STOCK
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(Title of Class of Securities)
45253H 10 1
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(CUSIP Number)
JANUARY 26, 2000
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(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:
/_/ Rule 13d-1(b)
/X/ Rule 13d-1(c)
/_/ Rule 13d-1(d)
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(1) The remainder of this cover page shall be filled out for reporting
person's initial filing on this form wiht 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. 45253H 10 1 13G PAGE 2 OF 9 PAGES
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- --------------------------------------------------------------------------------
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 599,657
EACH ------------------------------------------------------
REPORTING 7 SOLE DISPOSITIVE POWER
PERSON 0
WITH ------------------------------------------------------
8 SHARED DISPOSITIVE POWER
599,657
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
599,657
- --------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* /_/
- --------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
1.9%
- --------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
PN
- --------------------------------------------------------------------------------
* SEE INSTRUCTIONS BEFORE FILLING OUT!
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CUSIP NO. 45253H 10 1 13G PAGE 3 OF 9 PAGES
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- --------------------------------------------------------------------------------
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 184,952
EACH ------------------------------------------------------
REPORTING 7 SOLE DISPOSITIVE POWER
PERSON 0
WITH ------------------------------------------------------
8 SHARED DISPOSITIVE POWER
184,952
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
184,952
- --------------------------------------------------------------------------------
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
CERTAIN SHARES* /_/
- --------------------------------------------------------------------------------
11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
0.6%
- --------------------------------------------------------------------------------
12 TYPE OF REPORTING PERSON*
PN
- --------------------------------------------------------------------------------
* SEE INSTRUCTIONS BEFORE FILLING OUT!
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CUSIP NO. 45253H 10 1 13G PAGE 4 OF 9 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 1,507,547
EACH ------------------------------------------------------
REPORTING 7 SOLE DISPOSITIVE POWER
PERSON 0
WITH ------------------------------------------------------
8 SHARED DISPOSITIVE POWER
1,507,547
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,507,547
- --------------------------------------------------------------------------------
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. 45253H 10 1 13G PAGE 5 OF 9 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 1,507,547
EACH ------------------------------------------------------
REPORTING 7 SOLE DISPOSITIVE POWER
PERSON 0
WITH ------------------------------------------------------
8 SHARED DISPOSITIVE POWER
1,507,547
- --------------------------------------------------------------------------------
9 AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,507,547
- --------------------------------------------------------------------------------
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*
IA, CO
- --------------------------------------------------------------------------------
* SEE INSTRUCTIONS BEFORE FILLING OUT!
<PAGE>
CUSIP NO. 45253H 10 1 13G PAGE 6 OF 9 PAGES
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ITEM 1(a). NAME OF ISSUER:
Immunogen, Inc. ("Immunogen")
ITEM 1(b). ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:
333 Providence Highway
Norwood, MA 02062
ITEM 2(a). NAME OF PERSON FILING:
This Amendment to Schedule 13G is being filed on behalf of the
following persons*:
(i) Biotechnology Value Fund, L.P. ("BVF")
(ii) Biotechnology Venture Partners, L.P. ("BVF Venture")
(iii) BVF Partners L.P. ("Partners")
(iv) BVF Inc. ("BVF Inc.")
* Attached as Exhibit A is a copy of an agreement among
the persons filing (as specified hereinabove) that
this Amendment to Schedule 13G is being filed on
behalf of each of them.
ITEM 2(b). ADDRESS OF PRINCIPAL BUSINESS OFFICE:
The principal business office of the persons
comprising the group filing this Amendment to Schedule 13G is located at
227 West Monroe Street, Suite 4800, Chicago, Illinois, 60606.
ITEM 2(c). CITIZENSHIP:
BVF: a Delaware limited partnership
BVF Venture: a Delaware limited partnership
Partners: a Delaware limited partnership
BVF Inc.: a Delaware corporation
ITEM 2(d). TITLE OF CLASS OF SECURITIES:
Common Stock, par value $.01.
ITEM 2(e). CUSIP Number:
45253H 10 1
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CUSIP NO. 45253H 10 1 13G PAGE 7 OF 9 PAGES
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ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO RULE 13d-1(b), OR
13d-2(b) OR (c) CHECK WHETHER THE PERSON FILING IS ONE OF
THE FOLLOWING:
Not applicable as this Amendment to Schedule 13G is filed pursuant to Rule
13d-1(c).
ITEM 4. OWNERSHIP:
The information in items 1 and 5 through 11 on the cover
pages (pp. 2 - 5) on this Amendment to Schedule 13G is hereby incorporated by
reference.
ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS:
If this statement is being filed to report the fact that as
of the date hereof the reporting person has ceased to be the beneficial owner
of more than five percent of the class of securities check the following. /X/
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER
PERSON:
BVF shares voting and dispositive power over the shares of
the common stock it beneficially owns with Partners. BVF Venture also shares
voting and dispositive power over the shares of the common stock it
beneficially owns with Partners. Partners and BVF Inc. share voting and
dispositive power over the shares of the common stock they beneficially own
with, in addition to BVF and BVF Ventures, certain managed accounts on whose
behalf Partners, as investment manager, purchased such shares. None of the
managed accounts individually owns more than 5% of the common stock of
Immunogen.
ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH
ACQUIRED THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING
COMPANY:
Not applicable.
ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF A GROUP:
Not applicable.
ITEM 9. NOTICE OF DISSOLUTION OF GROUP:
Not applicable.
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CUSIP NO. 45253H 10 1 13G PAGE 8 OF 9 PAGES
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ITEM 10. CERTIFICATION
By signing below I certify that, to the best of my
knowledge and belief, the securities referred to above were not acquired and
are not held for the purpose of or with the effect of changing or influencing
the control of the issuer of the securities were not and are held in
connection with or as a participant in transaction having that purpose or
effect.
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: February 1, 2000
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, BVF Partners L.P., a Delaware limited partnership, and BVF Inc.,
a Delaware corporation, hereby agree and acknowledge that the information
required by the Amendment to Schedule 13G, 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: February 1, 2000
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
