When a Drug Fails

July 26, 2010

25 July | NY Times Editorial – The flameout of an enormously expensive drug to treat advanced breast cancer will pose a critical test for the Food and Drug Administration. Will the agency have the courage to reverse course when a medical treatment that it approved based on preliminary evidence flops badly in follow-up studies?

Two years ago, the F.D.A. gave Avastin, which is made by the Genentech unit of Roche, “accelerated approval” as a treatment for breast cancers that have spread to other parts of the body. Such cancers are essentially incurable so the best that current treatments can do is extend a patient’s life. 

The hurry-up mechanism allows approval of a drug that has not yet been proved safe and effective in thorough clinical trials but has shown promise that it might benefit patients with life-threatening diseases. Rather than make such patients wait, they are treated with the drug while the manufacturer completes additional tests. 

When Avastin was granted “accelerated approval” to treat advanced breast cancer, the primary evidence was a single clinical trial. It found that Avastin, when used with another drug, slowed progression of the disease but did not significantly extend patients’ lives. 

Now two follow-up trials by the manufacturer have failed to confirm even those meager gains. In the initial trial, Avastin held tumor progression at bay for five and a half months. In the two new trials, pairing Avastin with different chemotherapy drugs, the delay in tumor worsening was much shorter: up to three months in one trial and less than a month in the other. The Avastin combinations also caused serious side effects. 

Britain’s National Institute for Health and Clinical Excellence, a pace-setter in evaluating medical advances, issued draft guidance this month against using Avastin for advanced breast cancer patients in the National Health Service. It called the clinical trial data “disappointing” and the cost “too high for the limited and uncertain benefit it may offer patients.” 

By a 12-to-1 vote last week, an F.D.A. advisory committee quite sensibly urged the agency to revoke Avastin’s approval for breast cancer. That would not affect its other approvals, gained through the standard regulatory process, for treating colon, lung, kidney and brain cancers. Avastin would remain available to doctors for off-label use against breast cancer. Many insurers, however, might refuse to cover an unapproved use. 

The cost of Avastin has always seemed outrageously high for the medical benefits it confers. The wholesale price for a typical breast cancer patient is about $88,000 a year. Genentech has been capping annual spending at $57,000 for patients with incomes below $100,000. 

The F.D.A. has rarely removed drugs that were given accelerated approval and sometimes has failed even to compel completion of follow-up studies.  But there are signs it may get tougher. In June, the agency finally forced a leukemia drug off the market that had been given accelerated approval a decade ago, after a long- delayed follow-up study showed no clinical benefit and an increased risk of death. With Avastin, the follow-up studies were completed in a timely manner — with such meager results that withdrawal seems the right response.

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