FDA advisers unanimously back GlaxoSmithKline drug for kidney cancer, despite liver risks

FDA panel unanimously backs Glaxo cancer drug

GAITHERSBURG, Md. — Federal health advisers said Monday an experimental kidney cancer drug from GlaxoSmithKline PLC can benefit patients by slowing the disease, despite some risk of liver damage.

The Food and Drug Administration’s cancer drug panel voted unanimously in favor of Glaxo’s pazopanib pills for advanced kidney cancer, a rare but deadly form of the disease.

Glaxo studies showed higher rates of liver damage among patients taking the drug, compared with patients taking a dummy pill. FDA scientists said the drug likely caused two liver-related deaths in the study.

Despite those issues, panelists said the side effects were not significantly worse than similar cancer drugs.

“I think it’s an efficacious drug with significant toxicity, but I think the benefit-to-risk ratio is favorable considering all the data presented here,” said panel chair Dr. Gary Lyman of Duke University Medical Center.

Panelists added that Glaxo should be required to submit data from ongoing studies to ensure the drug’s liver toxicity does not increase over time.

“I think we need more information on this issue and that can be accomplished by monitoring it,” said Dr. Leonard Seeff, of the National Institutes of Health.

Glaxo Vice President Rafael Amado said the panel’s backing is “an important step” toward bringing the drug to market.

The FDA is expected to make a decision on the drug by Oct. 19. While the agency often follows the advice of its panels, it is not required to.

When London-based Glaxo began developing its drug there were few therapies for advanced kidney cancer, which killed about 13,000 people in the U.S. last year, according to the American Cancer Society.

But since 2005, the FDA has approved five new treatments for the disease, including Pfizer’s Sutent and Bayer’s Nexavar. Like those drugs, pazopanib works by targeting proteins that spur tumor growth.

Glaxo compared its drug to a dummy pill because rival treatments were not widely available when the company launched its trial in 2005.

Results from that 435-patient study showed patients taking the drug experienced a five-month halt in the progression of their cancer, though they did not live significantly longer.

The British drugmaker already markets the breast cancer pill Tykerb, which had sales of $189 million last year.

Earlier in the day, the same FDA panel narrowly backed a cancer drug from drugmaker Schering-Plough, despite results showing it did not extend patients’ lives.

The panel voted 6-4 that the potential benefits of the drug outweigh its toxic risks as a treatment for late-stage skin cancer.

Schering-Plough has asked the FDA to approve its drug PegIntron for patients whose skin cancer has spread to their lymph nodes, requiring surgery. The drug is already approved as a treatment for hepatitis C.

Company studies of the drug showed it lengthened the period of time before cancer recurred by about nine months, though patients didn’t live longer than those who did not receive the drug.

A majority of panelists said the drug’s ability to slow the disease outweighed its negative side effects.

Sales of Pegintron totaled $914 million in 2008. Kenilworth, N.J.-based Schering-Plough also markets Intron A, the only other FDA-approved drug for treatment of recurring skin cancer after surgery.

The panel vote was “an encouraging development toward the future treatment of melanoma,” the company said in a statement.