Bayer and South San Francisco-based Onyx Pharmaceuticals (NASDAQ: [[ticker:ONXX]]) have had a long-running partnership in marketing one cancer drug, and now they have a second one to start selling together.
The FDA said today it has approved regorafenib (Stivarga) as a new treatment in the U.S. for patients with colorectal cancer that has spread after treatment with prior therapies. The drug is designed to work by inhibiting multiple kinases, which is supposed to cut off blood flow to tumors, and interfere with tumor growth. The FDA cleared the treatment for sale about a month ahead of its legal deadline for completing its regulatory review.
The approval is big news for both companies. Bayer has told analysts it could generate $1 billion in peak annual sales for the new product. For Onyx, the approval enables it to become a more diversified company with not just two, but three, cancer drugs on the market. Onyx will co-promote Stivarga in the U.S., and stands to collect a 20 percent royalty on worldwide sales of the product as part of a legal settlement reached with Bayer in October. The new drug also provides a new treatment option for patients with colorectal cancer, which the National Institutes of Health estimates will kill 51,690 this year.
“We continue to believe that regorafenib is an underappreciated asset that has been given little credit in both our and Wall Street models,” said Cory Kasimov, an analyst with JP Morgan, in a note to clients today. Now that Onyx has three FDA-approved cancer drugs, he added, “we believe this highly attractive and diversified commercial presence sets the company apart from its biotech peers.”
Richard Pazdur, the head of the FDA’s cancer drug office, said in a statement that “Stivarga is the latest colorectal cancer treatment to demonstrate an ability to extend patients’ lives and is the second drug approved for patients with colorectal cancer in the past two months.” Sanofi’s ziv-afilbercept (Zaltrap) is the other recent approval.
Besides those two products, there are already a number targeted biotech drugs approved for colorectal cancer, including Genentech’s bevacizumab (Avastin), Eli Lilly’s cetuximab (Erbitux), Amgen’s panitumumab (Vectibix). The new drug from Bayer and Onyx has been priced at $9,350 for a 28-day cycle, which is competitive with other drugs, a company spokeswoman said.
The FDA approval was based mainly on a pivotal study of 760 patients whose disease had worsened after getting prior therapies. Researchers found that patients who were randomly assigned to get the Bayer/Onyx drug in addition to best supportive care lived a median of 6.4 months, compared with five months for those who got a placebo and best supportive care. The most common side effects for patients on the new drug included weakness, fatigue, and loss of appetite. The drug’s prescribing information includes a boxed warning to physicians about severe and fatal liver toxicity that was observed in clinical trials.
Bayer and Onyx have been co-marketing another drug, sorafenib (Nexavar), since it won FDA approval for treating kidney cancer in 2005. That product, now also approved for treating liver cancer, generated $1 billion in worldwide sales last year. Like Nexavar, the new product is thought to have potential against more than one tumor type. Bayer is seeking an additional FDA approval of regorafenib as a treatment for inoperable gastrointestinal stromal tumors (GIST).
