Bayer HealthCare Pharmaceuticals, Inc. and Onyx Pharmaceuticals, Inc. (Nasdaq: ONXX) announced the companies have begun enrolling patients in an international Phase 3 trial to evaluate Nexavar® (sorafenib) tablets for the treatment of patients with radioactive iodine-refractory, locally advanced or metastatic differentiated thyroid cancer. This Phase 3 trial was started based on the results from Phase 2 clinical trials evaluating Nexavar in patients with advanced thyroid cancer.

"Patients with thyroid cancer who failed to respond to surgical or radiotherapies, have limited treatment options to help them manage their disease," said Dimitris Voliotis, vice president, Nexavar clinical development, Bayer HealthCare Pharmaceuticals. "Recognizing this unmet need, we are evaluating Nexavar in this special patient population."

Phase 3 Trial Design

The DECISION (stuDy of sorafEnib in loCally advanced or metastatIc patientS with radioactive Iodine refractory thyrOid caNcer) trial is an international, multicenter, randomized, placebo-controlled study that will enroll approximately 400 patients with locally advanced or metastatic, radioactive iodine-refractory, differentiated thyroid cancer (papillary, follicular and Hurthle cell) who have received no prior systemic therapy.

Patients will be randomized to receive 400 mg of oral Nexavar twice daily or matching placebo. Patients will continue on treatment until disease progression, toxicity, non-compliance or withdrawal of consent. At the time of progression, patients receiving placebo will have an option to cross over to Nexavar at the discretion of the investigator, based on the patient's clinical status. The primary endpoint of the study is progression-free survival as defined by Response Evaluation Criteria in Solid Tumors (RECIST). Secondary endpoints include overall survival, time to progression and response rate. The safety and tolerability of the two treatment groups will also be compared.

Phase 2 Trial Results

Updated results from a single institution, investigator sponsored Phase 2 open-label study in 55 patients with metastatic, iodine refractory, thyroid cancer treated with Nexavar 400 mg twice daily were presented at the American Society of Clinical Oncology (ASCO) Annual Meeting, May 29-June 3, 2009 Orlando, FL, by Marcia Brose, M.D., Ph.D., an assistant professor of Hematology/Oncology and Otorhinolaryngology in the Abramson Cancer Center at the University of Pennsylvania, Philadelphia, PA, U.S.A. In 50 evaluable patients, 18 (36 percent) had a partial response per RECIST criteria. Updated survival results on the first 30 patients enrolled into the study demonstrated that across all histologies the median progression-free survival (PFS) was 63 weeks and the median overall survival was 140 weeks. The most common adverse events (AE) seen in the trial were hand-foot skin reaction, rash, fatigue, stomatitis/mucositis, weight loss, and musculoskeletal pain, and were predominantly grade 1 or 2. Dr. Brose and Martin J. Schlumberger, Institut Gustave-Roussy, Villejuif, France, are the lead investigators on the Phase 3 trial.

"Based on the positive signal generated in the Phase 2 trial, the initiation of this Phase 3 represents progress in exploring the full potential of Nexavar in a variety of treatment settings and tumor types," said Todd Yancey, M.D., vice president of clinical development at Onyx. "Building on our successful foundation of treating unresectable liver cancer and advanced kidney cancer, we are hopeful that this Phase 3 trial will lead to a new treatment option for patients with non-responsive thyroid cancer."

About Thyroid Cancer

Thyroid cancer, one of the few cancers that has increased in incidence over the past several years, is the sixth most common cancer in women and about three times as many women as men get thyroid cancer.(1) There are more than 140,000 new cases of thyroid cancer and more than 35,000 people die worldwide each year.(2)

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 80 countries for the treatment of patients with liver cancer and in more than 90 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 breast cancer, colorectal cancer, lung cancer, ovarian cancer, and as an adjuvant therapy for liver 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® (sorafenib) tablets, a small molecule drug.

Forward Looking Statements

This news release may contain forward-looking statements based on current assumptions and forecasts made by Bayer Group or subgroup 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 which are available on the Bayer Web site at http://www.bayer.com. 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 timing, progress and results of the clinical development, safety, regulatory processes, commercialization efforts or commercial potential 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, 2008, 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 Healthcare Pharmaceuticals, Inc.

References

(1) American Cancer Society

(2) Globocan 2002, World Health Organization

Source: Bayer HealthCare Pharmaceuticals Inc