Nexavar First FDA-Approved Drug Therapy For Liver Cancer

Bayer HealthCare Pharmaceuticals and Onyx Pharmaceuticals, Inc. (Nasdaq: ONXX) today announced that the U.S. Food and Drug Administration (FDA) has approved a supplemental New Drug Application for Nexavar® (sorafenib) tablets for the treatment of patients with unresectable hepatocellular carcinoma (HCC), or liver cancer. Nexavar, an oral anticancer drug, is the first approved systemic therapy for liver cancer and the only one shown to significantly improve overall survival in patients with the disease. In 2005 Nexavar became the first new treatment in more than a decade for advanced kidney cancer, and is currently approved in more than 60 countries for this indication.

“The approval of Nexavar in liver cancer marks the second time in two years that this novel kinase inhibitor has been granted FDA approval on a Priority Review basis, making it rapidly available to patients who previously had limited treatment options,” said Arthur Higgins, chairman of the Executive Committee of Bayer HealthCare. “This milestone will likely establish Nexavar as the standard systemic therapy for the treatment of liver cancer, and is a turning point in improving treatment outcomes in patients facing the devastating impact of this disease.”

“Liver cancer is one of the cancers in which the number of related deaths continues to increase,” said Hollings C. Renton, chairman, president and chief executive officer of Onyx Pharmaceuticals, Inc. “This second approval for Nexavar demonstrates our commitment to expediting the clinical development of this innovative therapy to treat today’s unmet needs in cancer. We are grateful to the patients, families and investigators who make this important research possible.”

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 More than 600,000 cases of liver cancer are diagnosed worldwide each year3 (about 19,000 in the United States,4 54,0005 in Europe,6 and 390,000 in China, Korea and Japan6) and incidence is increasing.7 In 2002 approximately 600,000 people died of liver cancer including 13,000 in the United States, 57,0005 in Europe and approximately 360,000 in China, Korea and Japan.6 Currently, the 5-year survival rate for liver cancer patients in the United States is 11 percent.8

“The American Liver Foundation (ALF) is always pleased when new therapies prove effective for those affected by liver disease. Researchers worldwide, including those supported by ALF, have spent decades studying liver cancer,” said James L. Boyer, M.D., chairman, board of directors, American Liver Foundation. “This new treatment provides a valuable option for liver cancer patients and will enable ALF to further promote the treatment of liver disease through our education and advocacy efforts.”

The companies also announced that an innovative patient support program - Resources for Expert Assistance and Care Helpline (REACH®) - is available to answer questions about Nexavar treatment, reimbursement, and patient support. For more information, healthcare providers and patients may contact the REACH program at 1.866.NEXAVAR (1.866.639.2827).

Phase 3 Data Summary
The FDA approval was based on positive data from the international Phase 3 placebo-controlled Sorafenib HCC Assessment Randomized Protocol (SHARP) trial which demonstrated that Nexavar improved overall survival by 44 percent in patients with HCC (HR=0.69; p=0.0006) versus placebo. In the study, median overall survival was 10.7 months in Nexavar-treated patients compared to 7.9 months in those taking placebo. No indication of imbalances was observed in serious adverse events between the Nexavar and placebo-treated groups with the most commonly observed adverse events in patients receiving Nexavar being diarrhea and hand-foot skin reaction. Based on these data, the European Commission granted marketing authorization to Nexavar for the treatment of patients with hepatocellular carcinoma on October 29, 2007.

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 unresectable hepatocellular carcinoma, 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. Bleeding with a fatal outcome from any site was reported in 2.4% for Nexavar vs. 4% in placebo. The incidence of treatment-emergent cardiac ischemia/infarction was 2.7% for Nexavar vs. 1.3% for placebo. Most common adverse events reported with Nexavar in patients with unresectable HCC were diarrhea, fatigue, weight loss, anorexia, nausea and hand-foot skin reaction. Grade 3/4 adverse events were 45% for Nexavar vs. 32% 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.