WAYNE, N.J. and SOUTH SAN FRANCISCO, Calif., Feb. 25, 2013 /PRNewswire/ -- Intended for U.S. Media Only -- Bayer HealthCare and Onyx Pharmaceuticals, Inc. (NASDAQ: ONXX) announced today that the U.S. Food and Drug Administration (FDA) approved Bayer's Stivarga ® (regorafenib) tablets to treat patients with locally advanced, unresectable or metastatic gastrointestinal stromal tumor (GIST) who have been previously treated with imatinib mesylate and sunitinib malate. 1 Stivarga was approved by the FDA in September 2012 for the treatment of patients with metastatic colorectal cancer (mCRC) who have been previously treated with fluoropyrimidine-, oxaliplatin- and irinotecan-based chemotherapy, an anti-VEGF therapy, and, if KRAS wild type, an anti-EGFR therapy. 1 (Photo: http://photos.prnewswire.com/prnh/20130225/NY62678 ) "The FDA's decision marks the second approval for Stivarga – first in metastatic colorectal cancer last year and now in locally advanced, unresectable or metastatic GIST, where there is a high unmet medical need for patients who have exhausted all approved treatment options," said Pamela A. Cyrus, MD, Vice President and Head of U.S. Medical Affairs, Bayer HealthCare Pharmaceuticals. "These regulatory milestones underscore Bayer's commitment to deliver effective products for difficult-to-treat cancers." Stivarga is a Bayer compound developed by Bayer and jointly promoted by Bayer and Onyx in the United States. In 2011, Bayer entered into an agreement with Onyx, under which Onyx receives a royalty on all global net sales of Stivarga in oncology. The approval of Stivarga in GIST is based on data from the pivotal Phase III GRID ( GIST – Regorafenib In Progressive Disease) trial, which showed that Stivarga plus best supportive care (BSC) statistically significantly improved progression-free survival (PFS) compared to placebo plus BSC (HR=0.27 [95% CI 0.19-0.39], p<0.0001) in patients with locally advanced, unresectable or metastatic GIST who have been previously treated with imatinib mesylate and sunitinib malate. 1 The median PFS was 4.8 months in the Stivarga arm versus 0.9 months in the placebo arm (p<0.0001). There was no statistically significant difference in overall survival at the time of the planned interim analysis based on 29% of the total events for the final analysis. At the time of disease progression as assessed by central review, the study blind was broken and all patients were offered the opportunity to take Stivarga at the investigator's discretion. Fifty-six (85%) patients randomized to placebo and 41 (31%) patients randomized to Stivarga received open-label Stivarga. 1 The most frequently observed adverse drug reactions (≥ 30%) in Stivarga-treated patients vs. placebo-treated patients in GIST, respectively, were: hand-foot skin reaction (HFSR) / palmar-plantar erythrodysesthesia (PPE), hypertension, asthenia/fatigue, diarrhea, mucositis, dysphonia, infection, decreased appetite and food intake, and rash. The Stivarga label includes a boxed warning citing the risk of hepatotoxicity. Severe and sometimes fatal hepatotoxicity has been observed in clinical trials. 1 "While great progress has been made in the treatment of GIST since the introduction of kinase inhibitors as effective therapies for this orphan disease, we have been looking for additional, effective treatments for GIST patients whose disease worsens despite currently approved therapies," said George D. Demetri, MD, Principal Investigator of the GRID study and Director of the Center for Sarcoma and Bone Oncology at the Dana-Farber Cancer Institute in Boston, MA. "These data show that regorafenib can slow disease progression in patients who are no longer responding to other approved therapies and may provide another avenue for GIST patients who would otherwise have no FDA-approved treatment option." About Gastrointestinal Stromal Tumor (GIST) GIST is the most common form of sarcoma (a type of cancer that develops from certain tissues, like bone or muscle) involving the gastrointestinal tract. 2 In the United States, it is estimated that there are approximately 4,000-5,000 new cases of GIST diagnosed each year, of which about 1,500 have already metastasized at diagnosis. 2,3 GIST may not cause any symptoms and may be found incidentally when the doctor is looking for other problems. 3About the GRID Study GRID was a randomized, double-blind, placebo-controlled, multi-center, cross-over Phase III study of regorafenib for the treatment of GIST. It randomized 199 patients who had been previously treated with imatinib mesylate and sunitinib malate. Patients were randomized in a 2:1 ratio to receive either regorafenib plus BSC or placebo plus BSC to evaluate efficacy and safety. Treatment cycles consisted of 160 mg regorafenib (or matching placebo) once daily for three weeks on / one week off plus BSC. Patients continued therapy until disease progression or unacceptable toxicity. The primary endpoint was PFS, and the key secondary outcome measure was OS. The safety and tolerability of the two treatment groups were also compared. 4About Stivarga (regorafenib)Stivarga is indicated for the treatment of patients with locally advanced, unresectable or metastatic gastrointestinal stromal tumor (GIST) who have been previously treated with imatinib mesylate and sunitinib malate. 1 It is also indicated for the treatment of patients with mCRC who have been previously treated with fluoropyrimidine-, oxaliplatin- and irinotecan-based chemotherapy, an anti-VEGF therapy, and, if KRAS wild type, an anti-EGFR therapy. 1 Stivarga is an inhibitor of multiple kinases involved in normal cellular functions and in pathologic processes such as oncogenesis, tumor angiogenesis, and maintenance of the tumor microenvironment. 1 Stivarga was developed under the Fast Track program and received priority review designations for locally advanced, unresectable or metastatic GIST and mCRC from the FDA. These designations are granted by the FDA to expedite the development and review of drugs to treat serious diseases and fill an unmet medical need (fast track), and given to drugs that provide a treatment where no adequate therapy exists (priority review).