SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                                    FORM 8-K

                                 CURRENT REPORT

                         PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934


        DATE OF REPORT (DATE OF EARLIEST EVENT REPORTED): AUGUST 27, 2002
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                                 IMMUNOGEN, INC.
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             (Exact name of registrant as specified in its charter)


                                                   
MASSACHUSETTS                       0-17999                     04-2726691
- ---------------                   ------------             -------------------
(State or other                   (Commission                 (IRS Employer
jurisdiction of                   File Number)             Identification No.)
incorporation)
128 SIDNEY STREET, CAMBRIDGE, MA 02139 --------------------------------------------------- (Address of principal executive offices) (Zip Code) Registrant's telephone number, including area code: (617) 995-2500 ITEM 5. OTHER EVENTS. On August 27, 2002, ImmunoGen, Inc. (the "Company") announced that, effective immediately, its Board of Directors has authorized the repurchase of up to 4.1 million shares of the Company's common stock. The repurchases are to be made at the discretion of management and as market conditions warrant. No time limit was set for the completion of the repurchase program. The press release announcing the common stock repurchase program is filed as an exhibit to this Form 8-K, and is incorporated by reference into this Item 5. The foregoing description of the press release and the transactions contemplated therein is qualified in its entirety by reference to such exhibit. ITEM 7. FINANCIAL STATEMENTS AND EXHIBITS. (c) Exhibits. 99.1 The Company's Press Release dated August 27, 2002. SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the Company has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. IMMUNOGEN, INC. ---------------- (Registrant) Date: August 27, 2002 /s/ Gregg D. Beloff ------------------- Gregg D. Beloff Chief Financial Officer and Vice President EXHIBIT INDEX - -------------- EXHIBIT NUMBER DESCRIPTION -------- ----------- 99.1 The Company's Press Release dated August 27, 2002.



                                                                    EXHIBIT 99.1


IMMUNOGEN, INC.
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128 Sidney Street, Cambridge, MA 02139-4239
                                        TEL: (617) 995-2500  FAX: (617) 995-2510

CONTACTS:

   Carol Hausner (Investors)                      Pete Holmberg (Media)
   Senior Director, Investor Relations and        Rx Communications Group, LLC
   Corporate Communications                       Tel: (917) 501-7434
   Tel: (617) 995-2500                            pholmberg@rxir.com
   info@immunogen.com

FOR IMMEDIATE RELEASE

               IMMUNOGEN, INC. ANNOUNCES SHARE REPURCHASE PROGRAM

CAMBRIDGE, MA, AUGUST 27, 2002 - ImmunoGen, Inc. (Nasdaq: IMGN), a
biopharmaceutical company currently focusing on the development of targeted
anti-cancer therapeutics, today announced that, effective immediately, its Board
of Directors has authorized the repurchase of up to 4.1 million shares of
ImmunoGen common stock. The repurchases are to be made at the discretion of
management and as market conditions warrant. No time limit was set for the
completion of this program. ImmunoGen recently announced that it would be
issuing 4.1 million shares of its common stock to Shire Biochem, Inc. pursuant
to the exercise of common share purchase warrants held by Shire Biochem, Inc.

"The current market price of our shares provides us with the unique opportunity,
through a share repurchase program, to offset the dilution associated with the
recent issuance of shares to Shire," said Mitchel Sayare, Ph.D., Chairman and
CEO of ImmunoGen. "We are very confident of our long-term prospects and, because
of our strong cash position, we can pursue this program without adversely
affecting our long-term plans."

ABOUT IMMUNOGEN, INC.

ImmunoGen, Inc. develops innovative biopharmaceuticals for the treatment of
cancer. The Company's TAP technology couples highly potent cytotoxic agents with
tumor-targeting antibodies to create effective new treatments for cancer with
minimal damage to normal tissue. Two TAP products developed by ImmunoGen are in
clinical trials - cantuzumab mertansine and huN901-DM1/BB-10901; the former is
licensed to GlaxoSmithKline, the latter is licensed to British Biotech in
certain territories. Several companies are developing TAP products comprised of
ImmunoGen's TAP technology and the partner's antibody - Genentech
(Trastuzumab-DM1), Millennium (MLN591DM1) and Boehringer Ingelheim (bivatuzumab
mertansine). ImmunoGen also has multi-target agreements with Genentech, Abgenix,
and Millennium.

THIS PRESS RELEASE INCLUDES FORWARD-LOOKING STATEMENTS BASED ON MANAGEMENT'S
CURRENT EXPECTATIONS. FACTORS THAT COULD CAUSE FUTURE RESULTS TO DIFFER
MATERIALLY FROM SUCH EXPECTATIONS INCLUDE, BUT ARE NOT LIMITED TO: THE SUCCESS
OF THE COMPANY'S RESEARCH STRATEGY; THE APPLICABILITY OF THE DISCOVERIES MADE
THEREIN; THE DIFFICULTIES INHERENT IN THE DEVELOPMENT OF PHARMACEUTICALS,
INCLUDING UNCERTAINTIES AS TO THE TIMING AND RESULTS OF PRECLINICAL STUDIES;
DELAYED ACHIEVEMENTS OF MILESTONES; RELIANCE ON COLLABORATORS; UNCERTAINTY AS TO
WHETHER THE COMPANY'S POTENTIAL PRODUCTS WILL SUCCEED IN ENTERING HUMAN CLINICAL
TRIALS AND UNCERTAINTY AS TO THE RESULTS OF SUCH TRIALS; UNCERTAINTY AS TO
WHETHER ADEQUATE REIMBURSEMENT FOR THESE PRODUCTS WILL EXIST FROM THE
GOVERNMENT, PRIVATE HEALTHCARE INSURERS AND THIRD-PARTY PAYORS; THE
UNCERTAINTIES AS TO THE EXTENT OF FUTURE GOVERNMENT REGULATION OF THE
PHARMACEUTICAL BUSINESS; AND OTHER FACTORS DESCRIBED IN IMMUNOGEN'S PERIODIC
FILINGS WITH THE SECURITIES AND EXCHANGE COMMISSION.

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