With the arrival of two revolutionary treatment strategies, immunotherapy and personalized medicine, cancer researchers have found new hope — and a problem that is perhaps unprecedented in medical research.
There are too many experimental cancer drugs in too many clinical trials, and not enough patients to test them on.
The logjam 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.
In July, an expert panel of the Food and Drug Administration approved a groundbreaking new leukemia treatment, a type of immunotherapy. Companies are scrambling to develop other drugs based on using the immune system itself to attack cancers.
Many of these experimental candidates in trials are quite similar. Yet each drug company wants to have its own proprietary version, seeing a potential windfall if it receives F.D.A. approval.
As a result, there are more than 1,000 immunotherapy trials underway, and the number keeps growing. "It's hard to imagine we can support more than 1,000 studies," said Dr. Daniel Chen, a vice president at Genentech, a biotechnology company.