Bayer and Onyx Announce Nexavar Data Presentations at 44th American Society of Clinical Oncology Annual Meeting

WAYNE, N.J. and EMERYVILLE, Calif., May 16 /PRNewswire-FirstCall/ -- Bayer HealthCare Pharmaceuticals, Inc. and Onyx Pharmaceuticals, Inc. (Nasdaq: ONXX) today announced more than 40 data presentations at the 2008 American Society of Clinical Oncology (ASCO) annual meeting demonstrating the potential for Nexavar(R) (sorafenib) tablets in multiple tumor types as a single agent or in combination with other agents.

"Data at ASCO will expand upon and support the proven efficacy and tolerability of Nexavar in liver cancer and advanced kidney cancer and provide new insight into the potential of Nexavar in additional types of cancer," said Henry Fuchs, MD, executive vice president and chief medical officer of Onyx Pharmaceuticals. "Highlights include studies demonstrating that Nexavar extends life for Asian patients with liver cancer; provides an effective, well-tolerated option for elderly patients with advanced kidney cancer and may provide benefit and warrants further study in heavily pretreated patients with non-small cell lung cancer."

"Along with international study groups and investigators, Bayer and Onyx are committed to a comprehensive clinical trial program evaluating Nexavar for additional types of cancer including lung cancer, breast cancer, melanoma and adjuvant use in kidney cancer," Susan Kelley, MD, vice president, Therapeutic Area Oncology, Bayer HealthCare Pharmaceuticals. "With its proven track record in two cancers, dual-targeted mechanism and proven tolerability, we continue to identify important new areas where Nexavar may provide clinical benefit for people affected by cancer."

Nexavar's Differentiated Mechanism

Nexavar targets both the tumor cell and tumor vasculature. In preclinical studies, Nexavar has been shown to target members of two classes of kinases known to be involved in both cell proliferation (growth) and angiogenesis (blood supply) -- two important processes that enable cancer growth. These kinases included Raf kinase, VEGFR-1, VEGFR-2, VEGFR-3, PDGFR-B, KIT, FLT-3 and RET.

Nexavar is currently approved in more than 40 countries for the treatment of patients with unresectable liver cancer and in more than 70 countries for the treatment of patients with advanced kidney cancer. Nexavar is also being evaluated by the companies, international study groups, government agencies and individual investigators as a single agent or combination treatment in a wide range of cancers, including metastatic melanoma, lung cancer, breast cancer and as an adjuvant therapy for kidney cancer.

Important Safety Considerations For Patients Taking Nexavar

Based on the currently approved U.S. package insert for the treatment of patients with unresectable hepatocellular carcinoma and advanced kidney cancer, hypertension may occur early in the course of therapy and blood pressure should be monitored weekly during the first six weeks of therapy and treated as needed. In HCC patients, bleeding with a fatal outcome from any site was reported in 2.4% for Nexavar and 4% in placebo. The incidence of treatment-emergent cardiac ischemia/infarction was 2.7% for Nexavar vs. 1.3% for placebo. In RCC patients, incidence of bleeding regardless of causality was 15% for Nexavar vs. 8% for placebo and the incidence of treatment-emergent cardiac ischemia/infarction was 2.9% for Nexavar vs. 0.4% for placebo. Most common adverse events >/=20% related to Nexavar for both HCC and RCC were fatigue, weight loss, rash/desquamation, hand-foot skin reaction, alopecia, diarrhea, nausea, and abdominal pain. Grade 3/4 adverse events in HCC and RCC patients, respectively, were 45% for Nexavar vs. 32% for placebo and 38% for Nexavar and 28% for placebo. Women of child-bearing potential should be advised to avoid becoming pregnant and advised against breast-feeding. In cases of any severe or persistent side effects, temporary treatment interruption, dose modification or permanent discontinuation should be considered.

About Bayer HealthCare Pharmaceuticals Inc.

Bayer HealthCare Pharmaceuticals Inc. is the U.S.-based pharmaceuticals unit of Bayer HealthCare LLC, a division of Bayer AG. One of the world's leading, innovative companies in the healthcare and medical products industry, Bayer HealthCare combines the global activities of the Animal Health, Consumer Care, Diabetes Care, and Pharmaceuticals divisions. In the U.S., Bayer HealthCare Pharmaceuticals comprises the following business units: Women's Healthcare, Diagnostic Imaging, Specialized Therapeutics, Hematology/Cardiology and Oncology. The company's aim is to discover and manufacture products that will improve human health worldwide by diagnosing, preventing and treating diseases.

About Onyx Pharmaceuticals, Inc.

Onyx Pharmaceuticals, Inc. is a biopharmaceutical company committed to improving the lives of people with cancer. The company, in collaboration with Bayer HealthCare Pharmaceuticals, Inc., is developing and marketing Nexavar(R) (sorafenib) tablets, a small molecule drug. For more information about Onyx, visit the company's website at http://www.onyx-pharm.com.

Forward-Looking Statements

This news release contains forward-looking statements based on current assumptions and forecasts made by Bayer Group management. Various known and unknown risks, uncertainties and other factors could lead to material differences between the actual future results, financial situation, development or performance of the company and the estimates given here. These factors include those discussed in our annual and interim reports filed with the Frankfurt Stock Exchange. The company assumes no liability whatsoever to update these forward-looking statements or to conform them to future events or developments.

This news release also contains "forward-looking statements" of Onyx within the meaning of the federal securities laws. These forward-looking statements include without limitation, statements regarding the timing, progress and results of the clinical development, safety, regulatory processes, and commercialization efforts of Nexavar. These statements are subject to risks and uncertainties that could cause actual results and events to differ materially from those anticipated. Reference should be made to Onyx's Annual Report on Form 10-K for the year ended December 31, 2007, filed with the Securities and Exchange Commission under the heading "Risk Factors" and Onyx's Quarterly Reports on Form 10-Q for a more detailed description of such factors. Readers are cautioned not to place undue reliance on these forward- looking statements that speak only as of the date of this release. Onyx undertakes no obligation to update publicly any forward-looking statements to reflect new information, events, or circumstances after the date of this release except as required by law.

Nexavar(R) (sorafenib) tablets is a registered trademark of Bayer HealthCare Pharmaceuticals, Inc.

SOURCE Bayer HealthCare Pharmaceuticals, Inc.; Onyx Pharmaceuticals, Inc.