New Data from Satraplatin Phase 3 Trial in Second-Line Castrate-Refractory Prostate Cancer Presented at 2009 ASCO Annual Meeting

Corporate news announcement processed and transmitted by Hugin AS. The issuer is solely responsible for the content of this announcement. ---------------------------------------------------------------------- -------------- * SPARC trial analyses demonstrate pain at baseline, pain progression and progression-free survival at three months are predictive of overall survival in metastatic castrate-refractory prostate cancer patients previously treated with docetaxel * Data from several other trials evaluating satraplatin in combination with various anti-cancer therapies published in ASCO Proceedings Martinsried/Munich (Germany) and Princeton, N.J., June 2, 2009 - GPC Biotech AG (Frankfurt Stock Exchange: GPC) today announced that data from the double-blind, randomized satraplatin Phase 3 trial, the SPARC trial (Satraplatin and Prednisone Against Refractory Cancer), were presented at the 2009 American Society for Clinical Oncology (ASCO) Annual Meeting in Orlando, Florida. The SPARC trial evaluated satraplatin plus prednisone versus placebo plus prednisone in 950 patients with castrate-refractory prostate cancer (CRPC) who had progressed after initial chemotherapy. The data presented are retrospective analyses of the SPARC trial evaluating correlations between overall survival (OS) and pain at baseline, pain progression, and progression-free survival (PFS) at three months. One presentation ("Use of pain at baseline and pain progression to predict overall survival in patients with docetaxel pretreated metastatic castration-refractory prostate cancer: results from the SPARC trial," Sartor et al, Abstract #5148), analyzed the docetaxel-pretreated population (n= 488) in two separate ways: * The first analysis compared OS in those patients who had no pain (Present Pain Intensity (PPI) score < or =1) vs. those with pain (PPI > or =2) at time of entry to the trial. * The second analysis compared OS in those patients who experienced pain progression versus progression by pre-specified measures other than pain (as judged by the blinded Independent Review Committee (IRC)). Shorter OS time was observed in docetaxel-pretreated patients who had pain at baseline compared to those who did not. The median survival of patients with baseline pain (n=178) was 44 weeks versus 72 weeks for patients without baseline pain (n=287) [stratified hazard ratio: 0.59 (95% CI: 0.48-0.74), stratified log-rank p<0.0001]. The IRC found that 414 docetaxel-pretreated patients (84.8%) progressed as of the data cutoff date for the SPARC study. Of these, the median survival of patients showing pain progression (n=196) was 47 weeks, compared to 71 weeks for non-pain progressors (n=292) [stratified hazard ratio: 0.71 (95% CI: 0.57-0.87), stratified log-rank p=0.0022]. Thus, pain at baseline, as well as pain progression, were prognostic indicators of OS in the docetaxel-pretreated patient population. A second presentation ("Correlation of progression-free survival and overall survival in men with metastatic castration-resistant prostate cancer who failed first-line chemotherapy: results from the SPARC trial," Halabi et al, Abstract #5150) evaluated whether PFS at three months was predictive of OS and explored the statistical dependencies between PFS and OS. Of the 853 men alive at three months post-randomization, 477 (56%) had already progressed. The median survival for this group was 34.5 weeks versus 78.7 weeks in men who had not progressed at the same three months timepoint. [hazard ratio: 2.16 (95% CI =1.84-2.55), p-value <0.001]. The dependence between PFS and OS was 0.29 (95% confidence limits = 0.24-0.33, p-value < 0.00001). Thus PFS at three months was predictive of OS. Additional studies will be needed to assess the clinical relevance of the individual components of progression as defined in the SPARC trial to OS. Data from other Phase I and Phase II clinical trials evaluating satraplatin in combination with other cancer therapeutic drugs were published in the 2009 ASCO Annual Meeting Proceedings: - Phase II trial of bevacizumab and oral satraplatin and prednisone in docetaxel pretreated metastatic castrate resistant prostate cancer - Vaishampayan et al (Abstract #e16028). - Dose finding study of the combination of satraplatin and gemcitabine in patients with advanced solid tumors - Di Paola et al (Abstract #e13534). - A phase I study investigating the combination of orally bioavailable platinum and nonparticle albumin-bound paclitaxel in advanced solid tumors - Deshpande et al (Abstract #e13501). About Satraplatin Satraplatin, an investigational drug, is a member of the platinum family of compounds. Platinum-based drugs are a critical part of modern chemotherapy treatments and are used to treat a wide variety of cancers. All platinum drugs currently on the market require intravenous administration. Satraplatin is an oral compound that clinical trial patients are able to take at home. GPC Biotech has a license agreement with Yakult Honsha Co. Ltd. under which Yakult has exclusive commercialization rights to satraplatin for Japan. GPC Biotech is currently in discussions with Yakult regarding further development and registrational efforts for satraplatin. GPC Biotech in-licensed satraplatin from Spectrum Pharmaceuticals, Inc. About GPC Biotech GPC Biotech AG is a publicly traded biopharmaceutical company focused on developing anti-cancer drugs. The Company currently has two programs in clinical development: satraplatin, an oral platinum compound and RGB-286638, a multi-targeted protein kinase inhibitor. On February 18, 2009 the Company announced plans to combine its business with Agennix, Incorporated, a privately-held biotechnology company located in Houston, Texas. Agennix is developing oral talactoferrin, a product candidate that is currently in Phase 3 trials for non-small cell lung cancer. GPC Biotech AG is headquartered in Martinsried/Munich (Germany) and has a wholly owned U.S. subsidiary in Princeton, New Jersey. For additional information, please visit GPC Biotech's Web site at www.gpc-biotech.com. This press release contains forward-looking statements, which express the current beliefs and expectations of the management of GPC Biotech, including statements about the efficacy and safety of satraplatin. Such statements are based on current expectations and are subject to risks and uncertainties, many of which are beyond our control, that could cause future results, performance or achievements to differ significantly from the results, performance or achievements expressed or implied by such forward-looking statements. Actual results of future clinical trials of satraplatin could differ materially from the findings of the retrospective data analyses presented in this press release, and we caution investors not to place undue reliance on the forward-looking statements contained in this press release. Satraplatin may not be approved for marketing in a timely manner, if at all. Forward-looking statements speak only as of the date on which they are made and GPC Biotech undertakes no obligation to update these forward-looking statements, even if new information becomes available in the future. Satraplatin has not been approved by the FDA in the U.S., the EMEA in Europe or any other regulatory authority and no conclusions can or should be drawn regarding its safety or effectiveness. Only the relevant regulatory authorities can determine whether satraplatin is safe and effective for the use(s) being investigated. For further information, please contact: GPC Biotech AG Investor Relations & Corporate Communications Phone: +49 (0)89 8565-2693 ir@gpc-biotech.com In the U.S.: Laurie Doyle Director, Investor Relations & Corporate Communications Phone: +1 609-524-5884 usinvestors@gpc-biotech.com Additional media contacts for Europe: MC Services AG Phone: +49 (0) 89 210 228 0 Raimund Gabriel raimund.gabriel@mc-services.eu Hilda Juhasz hilda.juhasz@mc-services.eu Additional investor contact for Europe: Trout International LLC Lauren Rigg, Vice President Phone: +44 207 936 9325 lrigg@troutgroup.com --- End of Message --- GPC Biotech AG Fraunhoferstr. 20 Martinsried Germany WKN: 585150; ISIN: DE0005851505; Index: CDAX, Prime All Share, TECH All Share, DAX; Listed: Prime Standard in Frankfurter Wertpapierbörse, Freiverkehr in Börse Berlin, Freiverkehr in Bayerische Börse München, Freiverkehr in Börse Düsseldorf, Freiverkehr in Börse Stuttgart, Freiverkehr in Hanseatische Wertpapierbörse zu Hamburg, Freiverkehr in Niedersächsische Börse zu Hannover, Regulierter Markt in Frankfurter Wertpapierbörse;