October 23, 2008

Cougar Biotechnology Presents Positive CB7630 Phase II Data at EORTC-NCI-AACR Symposium

Cougar Biotechnology, Inc. (NASDAQ:CGRB) today announced that results from an ongoing Phase II clinical trial of Cougar's investigational drug CB7630 (abiraterone acetate) were presented today at the 20th EORTC-NCI-AACR Symposium on "Molecular Targets and Cancer Therapeutics." The Symposium is currently taking place in Geneva, Switzerland.

The Phase II clinical trial of CB7630 (COU-AA-002) is being conducted at the University of California, San Francisco Comprehensive Cancer Center with Dr. Charles J. Ryan, Associate Professor of Clinical Medicine, as the principal investigator. CB7630, in combination with prednisone, is administered once daily to chemotherapy-naive, ketoconazole-naive patients with castration resistant prostate cancer (CRPC), who had progressive disease despite treatment with LHRH analogues and other hormonal therapies. All of the 12 evaluable patients who were enrolled in the trial had radiological evidence of metastatic disease with bone metastases and 2 patients (17%) had soft tissue metastases.

In his oral presentation entitled, "A Phase II study of Abiraterone Acetate plus Prednisone in Patients with Castration Resistant Prostate Cancer (CRPC) and no Prior Therapy with Ketoconazole," Dr. Ryan presented data on the 12 evaluable patients treated in the trial. Of these patients, 11 (92%) experienced a confirmed decline in prostate specific antigen (PSA) levels of greater than 30%, 9 patients (75%) experienced a PSA decline of greater than 50% and 6 patients (50%) experienced PSA declines of greater than 90%. In addition, 2 (17%) of the 12 patients experienced undetectable PSA levels (less than 0.1 ng/ml) after treatment with CB7630. Of the 12 evaluable patients, 10 (83%) continue to be treated with CB7630 for over 6 months.

Alan H. Auerbach, Chief Executive Officer and President of Cougar Biotechnology, said, "The data from our COU-AA-002 trial presented at the AACR-NCI-EORTC Symposium continues to support the potential role of CB7630 in the treatment of CRPC. We continue to be pleased with the strong evidence of antitumor activity in patients with chemotherapy-naive, ketoconazole-naive disease, which represents a significant unmet medical need in prostate cancer."

Arturo Molina, M.D., M.S., FACP, Cougar's Chief Medical Officer and Executive Vice President of Clinical Research and Development, added, "We are pleased with the results of this Phase II study, which continues to support the potential role of CB7630 as a second-line hormonal therapy for patients with advanced prostate cancer who fail first-line hormonal treatment. This patient group continues to represent a market that is underserved with current treatments."

About Cougar Biotechnology

Cougar Biotechnology, Inc. is a Los Angeles-based biotechnology company established to in-license and develop clinical stage drugs, with a specific focus on the field of oncology. Cougar's oncology portfolio includes CB7630, a targeted inhibitor of the 17-alpha hydroxylase/c17,20 lyase enzyme, which is currently being studied in a Phase III clinical trial in prostate cancer; CB3304, an inhibitor of microtubule dynamics, which is currently in a Phase I trial in multiple myeloma; and CB1089, an analog of vitamin D, which has been clinically tested in a number of solid tumor types.

Further information about Cougar Biotechnology can be found at www.cougarbiotechnology.com.

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. These statements are often, but not always, made through the use of words or phrases such as "anticipates,""expects,""plans,""believes,""intends," and similar words or phrases. These forward-looking statements include, without limitation, statements related to the benefits to be derived from Cougar's drug development programs, including the potential advantages of CB7630 and its potential for use in the treatment of CRPC and in second-line hormone and chemotherapy treatment settings. Such statements involve risks and uncertainties that could cause Cougar's actual results to differ materially from the anticipated results and expectations expressed in these forward-looking statements. These statements are only predictions based on current information and expectations and involve a number of risks and uncertainties. Actual events or results may differ materially from those projected in any of such statements due to various factors, including the risks and uncertainties inherent in clinical trials, and drug development and commercialization, including the uncertainty of whether results of prior clinical trials of CB7630 will be predictive of results of later stage clinical trials, including Cougar's ongoing Phase III clinical trial, COU-AA-301. For a discussion of these and other factors, please refer to Cougar's annual report on Form 10-KSB for the year ended December 31, 2007, as well as other subsequent filings with the Securities and Exchange Commission. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. This caution is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. All forward-looking statements are qualified in their entirety by this cautionary statement and Cougar undertakes no obligation to revise or update this press release to reflect events or circumstances after the date hereof.