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Exhibit 99.1
FOR IMMEDIATE RELEASE
IMMUNOGEN REPORTS FAVORABLE PRECLINICAL RESULTS FOR huN901-DM1/BB-10901
- Results Presented at NCI-EORTC-AACR International Conference in Amsterdam -
CAMBRIDGE, MASS., NOVEMBER 8, 2000 - ImmunoGen, Inc. (Nasdaq: IMGN) today
announced that huN901-DM1/BB-10901, a Tumor-Activated Prodrug (TAP) for the
treatment of small-cell lung cancer (SCLC), was well-tolerated in monkeys when
administered on a weekly dosing schedule. In addition, the TAP showed
exceptional anti-tumor activity in mouse studies, even at very low doses. These
preclinical results were presented today at the 11th NCI-EORTC-AACR (National
Cancer Institute-European Organization for Research and Treatment of
Cancer-American Associate for Cancer Research) Symposium on New Drugs in Cancer
in Amsterdam.
"Demonstrating the safety of this TAP on a weekly dosing schedule in monkeys is
important because we intend to use this schedule in the upcoming human clinical
trials," said Mitchel Sayare, Ph.D., Chairman and CEO of ImmunoGen, Inc. "With
the conclusion of these final preclinical studies, we and our development
partner, British Biotech, are on track to submit an Investigational New Drug
(IND) application to the FDA later this year. We are eager to begin human
evaluation of this TAP because we believe huN901-DM1/BB-10901 holds great
promise to treat patients suffering from SCLC, an aggressive and usually fatal
disease."
HuN901-DM1/BB-10901 is a TAP created by conjugating the cytotoxic maytansinoid
drug DM1 with the humanized monoclonal antibody N901. In tumor xenograft models,
huN901-DM1/BB-10901 eradicated human SCLC tumors. In a direct comparison study,
even a low dose of huN901-DM1/BB-10901 was significantly more efficacious than
an optimal dose of topotecan, a chemotherapeutic agent approved for treatment of
SCLC. HuN901-DM1/BB-10901 demonstrated cures lasting at least 200 days in animal
models where the combination of cisplatin and VP-16, currently the most
effective SCLC agents, caused only a modest effect. In monkey studies, there was
minimal toxicity at total doses significantly higher than those which effected
cures in mice.
HuN901-DM1/BB-10901 is being developed in collaboration with British Biotech
plc. British Biotech is responsible for conducting the clinical trials necessary
to achieve regulatory approval in the US, EU and Japan. British Biotech has been
granted the exclusive right to develop and commercialize huN901-DM1/BB-10901 in
the European Union and Japan. ImmunoGen retains the rights to commercialize
huN901-DM1/BB-10901 in the United States and the rest of the world, as well as
the right to manufacture the product worldwide.
ImmunoGen, Inc. develops innovative biopharmaceuticals, primarily for cancer
treatment. The Company has created potent tumor-activated prodrugs, consisting
of drugs coupled to monoclonal antibodies for delivery to and destruction of
cancer cells. The Company's lead TAP, huC242-DM1/SB-408075 for treatment of
colorectal, pancreatic, and certain non-small-cell lung cancers, is currently
under evaluation in two Phase I/II human clinical trials. Besides British
Biotech, the Company has collaborative arrangements with SmithKline Beecham,
Genentech, Abgenix, and MorphoSys.
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 ABILITY
TO SECURE FUTURE FUNDING; 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; AND THE UNCERTAINTIES AS TO THE EXTENT OF FUTURE GOVERNMENT REGULATION
OF THE PHARMACEUTICAL BUSINESS.
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