GBC BIOTECH PRESENTS NEW DATA ON EFFICACY OF SATRAPLATIN.

GPC Biotech AG (Frankfurt Stock Exchange: GPC; TecDAX 30) has announced the presentation of new in vitro data on the efficacy of satraplatin in tumor cells resistant to both TAXOTERE (docetaxel) and TAXOL (paclitaxel). These data were presented in Florence, Italy at the 1st Conference on Cancer Therapeutics - Molecular Targets, Pharmacology and Clinical Applications.

"The data being presented today support the lack of cross resistance between satraplatin and the two taxanes that are currently approved for use as chemotherapeutic agents in the treatment of human cancers - TAXOTERE and TAXOL," said Marcel Rozencweig, M.D., senior vice president, Drug Development of GPC Biotech. "We expect that many of the patients in the satraplatin Phase 3 registrational trial will have been pre-treated with and failed on a taxane-based therapy prior to entering our study. Thus, these data are very encouraging."

The study evaluated the effect of satraplatin on two taxane- resistant cell lines. In this study, one of the cell lines expresses mutant tubulin, and the other cell line over-expresses P-glycoprotein (Pgp). These genetic alterations represent the two most significant known mechanisms of resistance to the taxane family of compounds. The P-glycoprotein resistance mechanism is also conferred on a number of other anticancer agents, including the common chemotherapy treatment, doxorubicin. The data showed that these two resistance mechanisms did not convey similar resistance to satraplatin.

About Satraplatin

Satraplatin is a member of the platinum family of compounds, but unlike platinum compounds currently on the market, satraplatin is orally administered. A registrational Phase 3 trial - the SPARC trial - for satraplatin in hormone-refractory prostate cancer (HRPC) has been initiated, following successful completion of a Special Protocol Assessment (SPA) by the U.S. Food and Drug Administration (FDA). The trial is now expanding in Europe following receipt of a Scientific Advice letter from the European Organization for the Evaluation of Medicinal Products (EMEA). In the U.S., the FDA has also granted fast track designation to satraplatin as a second-line chemotherapy treatment for patients with HRPC. Positive results from a randomized, 50-patient study in HRPC were presented at the ASCO Annual Meeting in June 2003. These data demonstrated statistical significance in time to disease progression, doubling progression-free survival in the satraplatin- treated group versus the control group. Phase 2 trials have been successfully completed in HRPC, as well as in ovarian cancer and small-cell lung cancer. Further information on satraplatin can be found in the Drug Discovery and Development section of the company's Web site at http://www.gpc-biotech.com.

GPC Biotech AG is a biotechnology company dedicated to discovering and developing new anticancer drugs through innovative discovery technologies and development approaches. The company's lead product candidate - satraplatin - is in a Phase 3 registrational study as a second-line chemotherapy treatment in hormone-refractory prostate cancer in both the U.S. and Europe, following successful completion of a Special Protocol Assessment (SPA) by the U.S. FDA and receipt of a Scientific Advice letter from the EMEA. The FDA has also granted fast track designation to satraplatin for this indication. Other anticancer programs in development include a monoclonal antibody with a novel mechanism-of-action and a cell cycle inhibitor. The company is leveraging its drug discovery technologies in novel ways to elucidate the mechanisms-of-action of drug candidates and to support the growth of its drug pipeline. The company has formed successful collaborations with a number of pharmaceutical firms, including ALTANA Pharma of ALTANA AG (FSE: ALT; NYSE: AAA), Aventis Pharma (PAVE.PSE; NYSE: AVE), Bayer AG (FSE: BAY; NYSE: BAY), Boehringer Ingelheim International GmbH, Eli Lilly and company (NYSE: LLY) and Spectrum Pharmaceuticals, Inc. (NASDAQ: SPPI). GPC Biotech AG is headquartered in Martinsried/Munich (Germany). The company's wholly owned U.S. subsidiary has research sites in Waltham, Massachusetts and Princeton, New Jersey.

For more information, visit http://ww.gpc-biotech.com or call 781/890-9007 (ext. 267) or 212/845-4239.