On-off dosing of cancer drugs does not help melanoma patients

Source: AAAS Science, April 2020

Drugs that home in on and block cell growth signals can dramatically shrink tumors, but all too often the cancer comes back. An attention-grabbing mouse study 7 years ago suggested these targeted drugs would work better at shrinking melanoma tumors if cancer patients got a break from their medicine every few weeks.

The first large trial to test this idea, however, has found that melanoma tumors grew back faster when patients were on such an “intermittent” dosing schedule. The study participants also lived no longer overall than those receiving the typical schedule of the drugs.

The disappointing results, to be presented today at part one of a virtual version of the American Association for Cancer Research’s annual meeting, throw cold water on a novel strategy for countering cancer drug resistance that is being tested in a number of clinical trials. “There were a lot of reasons to think this could work. … It seemed like a very powerful idea,” says oncologist Alain Algazi of the University of California (UC), San Francisco, who led the melanoma trial.