Pfizer Inc.’s advanced kidney cancer treatment may not be effective at prolonging the time some patients live without the disease getting worse, a Food and Drug Administration staff report said today.
The FDA said it was concerned that the number of U.S. patients who benefited from the therapy, chemically known as axitinib, was small. People who showed the most response were first treated with medicines known as cytokines, which are not used as much as newer treatments.
“Advice is sought on whether the issue of” survival free from disease progression is “being driven by a subset of patients that is likely to be scarce in the United States,” according to the report.
The medicine from New York-based Pfizer, the world’s biggest drugmaker, may compete with tivozanib from Aveo Pharmaceuticals Inc. in Cambridge, Massachusetts, which is also being tested to treat advanced kidney cancer. Both block receptors in the body thought to play a role in spreading tumors. Kidney cancer affects 296,000 people in the U.S., according to the American Cancer Society.
An advisory panel is scheduled to meet on axitinib Dec. 7 and make recommendations to the agency on the risks and benefits of the treatment. The FDA isn’t required to follow the panel’s advice.
Pfizer fell less than 1 percent to $19.84 at the close in New York. The shares have gained 13 percent this year.
More than a third of patients in the trial had received cytokines.
Kidney Cancer Treatments
Typical kidney cancer treatments, according to the National Institutes of Health, include surgery to remove part of all of the kidney, radiation, chemotherapy and other drugs such as Bayer AG’s Nexavar. Pfizer compared axitinib to Nexavar, which the FDA approved in 2005, in its final-phase clinical trial.
Results “indicate that axitinib has demonstrated a statistically significant and clinically meaningful improvement in efficacy” compared with Nexavar, Pfizer said in the report that it will present to the advisory panel Dec. 7.
The trial found axitinib kept the disease from progressing for a median of 6.7 months compared with 4.7 months for Nexavar, according to results released in June. The study included 723 patients. The FDA is expected to decide whether to approve Pfizer’s drug by March 13.