Onyx Pharmaceuticals Inc. increased the most in nine months after its Nexavar treatment for advanced liver cancer outperformed a potential competitor from Pfizer Inc. in trials.
Onyx rose $2.69, or 9.4 percent, to $31.18 at 4 p.m. New York time in Nasdaq Stock Market composite trading for the biggest single-day increase since July 22. The company gained 16 percent in the past 12 months.
Pfizer halted testing of anti-tumor drug Sutent as a liver cancer therapy because patients taking it had more serious side effects than those on Nexavar, the New York-based company said yesterday in a statement. The results leave Nexavar as the only approved medication for advanced liver cancer and will help the drug achieve sales of $1 billion this year, Onyx Chief Executive Officer Anthony Coles said today in a telephone interview.
The discontinuation of the Sutent study “is extremely positive” for shares of Emeryville, California-based Onyx, George Farmer, an analyst at Canaccord Adams Inc. in New York, said today in a note to investors. “Nexavar will probably hold a monopoly in this market for the foreseeable future.”
Nexavar, co-marketed by Onyx and Leverkusen, Germany-based Bayer AG, had worldwide sales of $844 million in 2009, Coles said. It is approved for use in patients with inoperable liver cancer and kidney cancer and is being tested in breast cancer and lung cancer, he said.
The results released by Pfizer show that “Nexavar is a unique compound with a unique mechanism of action,” Coles said. Nexavar is the only approved drug that inhibits a particular cancer-related protein known as B-Raf, he said.
Several drugs are in head-to-head testing with Nexavar to gain approval for use in liver cancer, including ABT-869, being co-developed by Abbott Laboratories of Abbott Park, Illinois, and Basel, Switzerland-based Roche AG, and New York-based Bristol-Myers Squibb Co.’s Brivanib.
Sutent, which was in the third and final round of testing required by U.S. regulators, failed to show improved survival compared with Nexavar, Pfizer said. The drug is already approved for kidney cancer and a digestive system malignancy.