29 May Only 1 in 5 Cancer Drugs Receiving FDA Accelerated Approval Have Proven Benefits in Confirmatory Trials
Posted at 11:47h
in Author Interviews, Brigham & Women's - Harvard, Cancer Research, FDA, JAMA, Pharmacology
MedicalResearch.com Interview with:
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Dr. Gyawali[/caption]
Bishal Gyawali MD PhD
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Accelerated approval pathway from the FDA allows cancer drugs to come to market sooner by showing improvement in surrogate measures such as change in tumor size. Surrogate measures do not reflect clinical benefit in terms of living longer or feeling better. So, when a drug receives accelerated approval, the drug is required to undergo a confirmatory trial to confirm that true clinical benefit from the drug actually exists.
Last year, a paper from the FDA argued that accelerated approval pathway is working effectively because 55% of such drugs confirmed clinical benefit. However, we saw that most of those drugs were actually improving only a surrogate measure even in confirmatory trials. So the confirmatory trials were not confirming clinical benefit but actually confirming benefit in a surrogate endpoint. We investigate that issue in our study using updated results from the confirmatory trials that were ongoing at the time of FDA review.
Our main finding is that only one-fifth of cancer drugs that received accelerated approval actually improved overall survival later in confirmatory trials. For, 20% of other drugs, the confirmatory trials tested the same surrogate endpoint as did the preapproval trial. For another 21%, the confirmatory trial showed benefit in a surrogate endpoint different from the one used in preapproval trial. Furthermore, when drugs fail to confirm clinical benefits in confirmatory trials, they still continue to remain on market.





Dan Ly[/caption]
Dan Ly, MD, MPP
Ph.D. Program in Health Policy
Harvard
MedicalResearch.com: What is the background for this study?
Response: There is some mixed evidence regarding whether state level tort reform reduces defensive medicine, or the practicing of medicine in such a way to reduce medical liability. This includes “positive” defensive medicine, or performing certain tests and procedures to reduce such liability. Other research finds that the perception of malpractice risk drives such defensive medicine, including the use of diagnostic imaging, such as CT scans and MRIs.
I was interested in exploring what influenced the perception of this risk, hypothesizing that, for a physician, a report of an injury against one’s colleague might increase the perception of this risk and lead to an increase the use of diagnostic imaging.

