IMCLONE SYSTEMS AND MERCK KGaA EXTEND COLLABORATION FOR THERAPEUTIC CANCER VACCINES

Business Wire, May 16, 1996

NEW YORK--(BUSINESS WIRE)--May 16, 1996--ImClone Systems Incorporated (Nasdaq: IMCL) today announced that it has extended its collaboration with Merck KGaA for the development of therapeutic cancer vaccines, specifically BEC-2, an anti-idiotypic vaccine, for use in small cell lung carcinoma and malignant melanoma. The collaboration continues a research and license agreement between the two companies which was signed in December of 1990.

"This extended agreement coupled with the data, which will be presented this month at the annual meeting of the American Society of Clinical Oncology, validates our cancer vaccine program," said Samuel D. Waksal, President and Chief Executive Officer of ImClone Systems. "In addition, the infusion of Merck KGaA revenues further strengthens our cash position over the next few years."

Under the terms of the modified agreement, ImClone will receive up to $11.7 million in license fees, quarterly and milestone payments in addition to the monies already received in the original agreement. In return, Merck KGaA will receive the marketing rights to BEC-2 for all therapeutic indications outside of North America. It is the intent of the parties that ImClone be the manufacturer of the product worldwide. ImClone also retains marketing rights in North America. Merck KGaA will pay for 60 percent of the development cost for the United States and Europe and 100 percent of development costs in all other territories. In addition, ImClone will be entitled to royalty payments based upon product sales outside of North America. ImClone and Merck KGaA are planning on entering pivotal studies for BEC-2 for use in treatment of small cell lung carcinoma in 1997.

Merck KGaA, a public company, is a leading European group dealing in the pharmaceutical, laboratory and specialty chemicals business sectors. The company's major pharmaceutical research targets are cardiovascular, CNS, immunologic/oncologic and metabolic diseases as well as contrast media. The worldwide operating company, headquartered in Darmstadt, Germany with 1995 sales of approximately 6.3 billion DM, employs approximately 28,100 people, 1,855 of them in R & D.

ImClone Systems Incorporated, headquartered in New York, is a biopharmaceutical company developing novel therapeutic products, including interventional therapeutics, blood cell growth factors, and cancer vaccines for the treatment of cancer and cancer-related disorders.

CONTACT: Andrea F. Rabney

Director of Corporate Development and Investor Relations

ImClone Systems Incorporated

(212) 645-1405

or

Karen Bergman (Media inquiries)

Lilian S. Stern (Investor inquiries)

Burns McClellan, Inc.

(212) 505-1919