Friday, May 21, 2004

Genentech Announces Webcast Discussions of Data Presented at ASCO

South San Francisco, Calif. -- May 21, 2004 --

Genentech, Inc. (NYSE:DNA) invites investors, the media and the general public to listen to audio webcasts discussing data presented at the American Society of Clinical Oncology (ASCO). Due to the extensive number of data presentations, Genentech will host two webcast discussions. The live webcasts can be accessed by going to Genentech's website at http://www.gene.com.

The first webcast will begin at 4:00 p.m. Pacific Time on June 6, 2004 and will be archived until 5:00 p.m. Pacific Time on June 13, 2004. An audio telephone replay will also be available beginning at 7:00 p.m. Pacific Time on June 6, 2004 through 7:00 p.m. Pacific Time on June 13, 2004. Access numbers for this replay are: 1-800-642-1687 (U.S./Canada) and 1-706-645-9291 (international); Conference ID number is 7566636.

The second webcast will begin at 5:00 p.m. Pacific Time on June 7, 2004 and will be archived until 5:00 p.m. Pacific Time on June 14, 2004. An audio telephone replay will also be available beginning at 8:00 p.m. Pacific Time on June 7, 2004 through 8:00 p.m. Pacific Time on June 14, 2004. Access numbers for this replay are: 1-800-642-1687 (U.S./Canada) and 1-706-645-9291 (international); Conference ID number is 7021508.

About Genentech
Genentech is a leading biotechnology company that discovers, develops, manufactures and commercializes biotherapeutics for significant unmet medical needs. Eighteen of the currently approved biotechnology products originated from or are based on Genentech science. Genentech manufactures and commercializes 13 biotechnology 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. For press releases and additional information about the company, please visit http://www.gene.com.