Abgenix to Seek a Corporate Partner to Commercialize ABX-CBL

FREMONT, Calif., December 7, 1999 - Abgenix, Inc. (Nasdaq: ABGX) is initiating a Phase III clinical trial comparing its antibody, ABX-CBL, with standard therapy for patients with steroid-resistant graft-versus-host disease (srGVHD), a serious, life-threatening disorder. Abgenix also indicated that it would seek a corporate partner to assist with the development and commercialization of ABX-CBL.

Abgenix is pursuing the Phase III trial of ABX-CBL based on promising results of a 59 patient Phase II trial of the drug. In that trial, srGVHD patients receiving higher doses of ABX-CBL had more than twice the 180-day survival rate observed in the lowest dose cohort, according to results presented at the annual meeting of the American Society of Hematology (ASH). Survival at 180 days for patients in the higher dose cohorts was 50% versus 22% in the lowest (presumed no effect) dose cohort.

"ABX-CBL demonstrated important clinical benefits as measured by response rate and survival in the Phase II clinical trial," said H. Joachim Deeg, M.D., Department of Transplantation Biology at Fred Hutchinson Cancer Research Center and Principal Investigator for the trial. "Given the limited options available for treating srGVHD patients, ABX-CBL has the potential to be an important new treatment for this disease."

"While we are enthusiastic about ABX-CBL's potential as a much needed treatment for srGVHD, our business strategy is to find corporate partners to commercialize the products we generate," stated R. Scott Greer, president and CEO of Abgenix. "Therefore, we would like to identify a pharmaceutical or biotech company with the development and marketing infrastructure to maximize the commercial potential of ABX-CBL. We plan to begin the Phase III trial on our own, but would like to have a partner on board before it is completed."

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Contact: Kurt Leutzinger, Abgenix, Inc.
510-608-6575
Porter Novelli
6-Dec-1999