Thursday, Dec 16, 1999

Genentech to Proceed With Phase III Trials of Experimental Anti-Angiogenesis Monoclonal Antibody

Primary objectives met in Phase II trials for colorectal and non-small cell lung cancer

South San Francisco, Calif. -- December 16, 1999 --

Genentech, Inc. (NYSE: DNA) announced today the decision to proceed with Phase III clinical trials studying the company's recombinant humanized monoclonal antibody to Vascular Endothelial Growth Factor (rhuMAb-VEGF) in combination with chemotherapy in metastatic colorectal cancer and metastatic non-small cell lung cancer. The decision to move forward is based on meeting the company's primary objectives in Phase II clinical trials.

"The further study of anti-VEGF in Phase III trials is an important next step for the Genentech BioOncology initiative," said Susan D. Hellmann, M.D., M.P.H., Genentech's executive vice president of development and product operations and chief medical officer. "We are pleased with the preliminary data from these two Phase II trials. Through the Phase III trials we will better understand the potential safety and efficacy profile of anti-VEGF in a larger patient population."

Specific plans for Phase III trials have yet to be determined. Genentech plans to sponsor the Phase III trial in colorectal cancer and is in discussions with the Eastern Cooperative Oncology Group (ECOG) to study rhuMAb-VEGF in conjunction with chemotherapy in a non-small cell lung cancer Phase III trial.

Genentech will work with the clinical trial investigators to prepare and submit the final analyses of the Phase II data for peer review and presentation at the upcoming May 2000 American Society of Clinical Oncology (ASCO) scientific meeting, and publication in a peer-reviewed medical journal.

The colorectal Phase II study enrolled 104 patients with previously untreated metastatic disease. The open-label trial randomized patients to receive either 5-FU/leukovorin alone or in combination with rhuMAb-VEGF.

The non-small cell lung cancer Phase II trial enrolled 99 patients with previously untreated metastatic disease. The open-label trial randomized patients to receive either carboplatinum/paclitaxel alone or in combination with rhuMAb-VEGF.

Vascular endothelial growth factor (VEGF) is a protein that is secreted from ischemic tissue (tissue lacking oxygen) and from malignant or cancerous cells. VEGF regulates new blood vessel formation, or angiogenesis, by binding to specific receptors on nearby blood vessels, causing new blood vessels to form. Research has shown that angiogenesis, by supplying blood to tumors, plays an important role in both tumor growth and metastasis. In preclinical research, rhuMAb-VEGF has been shown to bind to VEGF and prevent VEGF from binding to its receptors.

Genentech, Inc. is a leading biotechnology company that discovers, develops, manufactures and markets human pharmaceuticals for significant unmet medical needs. Twelve of the approved products of biotechnology stem from Genentech science. Genentech markets seven products directly in the United States. The company has headquarters in South San Francisco, California and is traded on the New York Stock Exchange under the symbol DNA.

# # #