2007 Press Releases

Nexavar Receives Positive Opinion from European Committee for Medicinal Products for Human Use for Treatment of Liver Cancer


WAYNE, N.J. and EMERYVILLE, Calif. — Sep. 21, 2007

Bayer HealthCare Pharmaceuticals (NYSE: BAY) and Onyx Pharmaceuticals, Inc. (Nasdaq: ONXX) today announced that the European Committee for Medicinal Products for Human Use (CHMP) has issued a positive opinion, recommending to grant marketing authorization for Nexavar® (sorafenib) tablets for the treatment of patients with hepatocellular carcinoma (HCC), or liver cancer. This positive CHMP opinion will be elevated to the European Commission where a likely favorable ruling could lead to Marketing Authorization for European Union Member States this year. Nexavar is currently approved in more than 50 countries for the treatment of patients with advanced kidney cancer.

"The positive opinion issued by the CHMP marks another significant milestone for Nexavar in liver cancer," said Gunnar Riemann, Ph.D., member of the Bayer HealthCare Executive Committee. "The Committee's decision underscores the potential of Nexavar to become the standard systemic drug therapy for the treatment of liver cancer."

The CHMP positive opinion was based on data from the Phase 3 Sorafenib HCC Assessment Randomized Protocol (SHARP) trial which demonstrated that Nexavar extended overall survival by 44 percent in patients with HCC (HR=0.69; p=0.0006) versus placebo. There were no meaningful differences in serious adverse event rates between the Nexavar and placebo-treated groups with the most commonly observed serious adverse events in patients receiving Nexavar being diarrhea and hand-foot skin reaction. Based on these data, a supplemental New Drug Application for Nexavar was also granted Priority Review status by the U.S. Food and Drug Administration (FDA) in August.

"This decision, coupled with the Priority Review status granted by the FDA, means that patients in these regions are one step closer to a new treatment for their liver cancer," said Hollings Renton, chairman, president and chief executive officer of Onyx Pharmaceuticals, Inc.

HCC, the most common form of liver cancer, is responsible for about 90 percent of the primary malignant liver tumors in adults.(1,2) Liver cancer is the sixth most common cancer in the world and the third leading cause of cancer-related deaths globally.(3) Over 600,000 cases of liver cancer are diagnosed globally each year(3) (about 19,000 in the United States(4) and 32,000 in the European Union(5)) and in 2002 approximately 600,000 people died of liver cancer including 13,000 in the United States, 57,000 in Europe and approximately 360,000 in China, Korea and Japan.(6)

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. Preclinical models have also demonstrated that Raf/MEK/ERK has a role in HCC; therefore blocking signaling through Raf-1 may offer therapeutic benefits in HCC.

Important Safety Considerations for U.S. Patients Taking Nexavar
Based on the currently approved package insert for the treatment of patients with 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. 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 treatment-emergent adverse events with Nexavar were diarrhea, rash/desquamation, fatigue, hand-foot skin reaction, alopecia, and nausea. Grade 3/4 adverse events were 38% for Nexavar vs. 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.

For U.S. Nexavar prescribing information, visit www.nexavar.com or call 1.866.NEXAVAR (1.866.639.2827).

About Onyx Pharmaceuticals, Inc.
Onyx Pharmaceuticals, Inc. is a biopharmaceutical company developing innovative therapies that target the molecular mechanisms that cause cancer. The company is developing Nexavar®, a small molecule drug, with Bayer Pharmaceuticals Corporation. For more information about Onyx's pipeline and activities, visit the company's web site at: www.onyx-pharm.com.

About Bayer HealthCare Pharmaceuticals
Bayer HealthCare Pharmaceuticals Inc. is the U.S.-based pharmaceuticals unit of Bayer HealthCare LLC, a division of Bayer AG. Its research and business activities are focused on the following areas: Diagnostic Imaging, Hematology/Cardiology, Oncology, Primary Care, Specialized Therapeutics and Women's Healthcare. The company's aim is to discover and manufacture products that will improve human health worldwide by diagnosing, preventing and treating diseases.

About Bayer Schering Pharma AG, Germany
Bayer Schering Pharma is a worldwide leading specialty pharmaceutical company. Its research and business activities are focused on the following areas: Diagnostic Imaging, Hematology/Cardiology, Oncology, Primary Care, Specialized Therapeutics and Women's Healthcare. With innovative products, Bayer Schering Pharma aims for leading positions in specialized markets worldwide. Using new ideas, Bayer Schering Pharma aims to make a contribution to medical progress and strives to improve quality of life.

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 Bayer's public reports filed with the Frankfurt Stock Exchange and with the U.S. Securities and Exchange Commission (including its Form 20-F). Bayer 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, 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, 2006, 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® (sorafenib) tablets is a registered trademark of Bayer Pharmaceuticals Corporation.

References
(1). World Health Organization. Hepatitis B. Available at:
http://www.who.int/csr/disease/hepatitis/whocdscsrlyo20022/en/.
Accessed April 10, 2007
(2). Penn State Milton S. Hershey Medical Center College of Medicine.
Malignant Hepatoma. Available at:
http://www.hmc.psu.edu/healthinfo/m/malignanthepatoma.htm. Accessed
April 10, 2007.
(3). International Agency for Cancer Research. GLOBOCAN 2002. Available
at: http://www-dep.iarc.fr. Accessed April 23, 2007.
(4). Jemal A et al. CA Cancer J Clin. 2007;57:43-66.
(5). International Agency for Cancer Research. EUCAN 1998. Available at:
http://www-dep.iarc.fr/eucan/eucan.htm. Accessed April 26, 2007.
(6). Ferlay J, et al., GLOBOCAN 2002. Cancer Incidence, Mortality and
Prevalence Worldwide. IARC CancerBase No.5, Version 2.0. IARCPress,
Lyon, 2004. Available at: http://www-dep.iarc.fr. Accessed April 10,
2007.