Saturday, August 19, 2017

Smaller studies can mean missed side effects

Pharmaceutical companies can't find patients for trials of experimental cancer drugs 

Dr. Peter Bach
Too few patients are available to cover all the clinical cancer drug trials being conducted.

That, at least, is the conclusion of a recent story by Gina Kolata in The New York Times.

Her article notes that the problem "is caused partly by companies hoping to rush profitable new cancer drugs to market, and partly by the nature of these therapies, which can be spectacularly effective but only in select patients."

There currently are more than 1,000 immunology trials underway, for example.

But Kolata says "immunotherapy trials have proliferated so quickly that major medical centers are declining to furnish patients to them. The Yale Cancer Center participates in fewer than 10 percent of [those] it is asked to join." 

The writer cites words of Dr. Peter Bach, director of the Center for Health Policy and Outcomes at Memorial Sloan Kettering Cancer Center: "I think there is a lot of exuberant rush to market. And we are squandering our most precious resource — patients."

Dr. Roy Herbst
She also quotes Dr. Roy Herbst, the Yale center's chief of medical oncology, to the effect that the companies sponsoring the trials aren't addressing new research questions but are merely "trying to get proprietary drugs approved."

Some companies are working on experimental drugs that attack and block mutations that tumors need to grow and thrive. The mutations sought by those targeted therapies, however, are extremely rare so pharmaceutical companies "may be forced to undertake a worldwide search for subjects that can last for years."

It took Pfizer three years, for example, "to locate 50 lung cancer patients who carried a rare aberration called ROS1, found in just 1 percent of patients."

Many new trials involve a limited number of patients, which can be risky.

Bach, according to Kolata, maintains that "the smaller the study and the shorter its duration, the more likely that what looks like an effect in a trial might simply be the result of chance" — which "leaves some of us evidence geeks wondering if it works."
Dr. Scott Ramsey

The writer also quotes Dr. Scott Ramsey, an oncologist at the Fred Hutchinson Cancer Research Center, that "in tiny studies, serious side effects can be missed."

Details of many clinical trials can be found in "Rollercoaster: How a man can survive his partner's breast cancer," a VitalityPress book I, Woody Weingarten, aimed at male caregivers.

No comments:

Post a Comment