Long-term results from a major federal study ease worries about the safety of a hormone-blocking drug that can lower a man’s chances of developing prostate cancer.
The drug cut prostate cancer risk by 30 percent without raising the risk of dying of an aggressive form of the disease as earlier results hinted it might.
The new work could prompt a fresh look at using the drug for cancer prevention. Experts say it could prevent tens of thousands of cases each year, saving many men from treatments with seriously unpleasant side effects.
The drug is sold as Proscar by Merck & Co. and in generic form as finasteride to treat urinary problems from enlarged prostates. It’s also sold in a lower dose as Propecia to treat hair loss.
A decade ago, the drug was found to cut the risk of prostate cancer. But there was a small rise in aggressive tumors among its users. Some researchers said that by shrinking the prostate, the drug was just making these tumors easier to find in a biopsy sample – not causing them.
But the concern led the Food and Drug Administration to turn down the drug for cancer prevention and warnings were added to its label.
Now, with 18 years of follow-up from that earlier study, researchers report that men on the drug were no more likely to die than those not taking it.
That’s reassuring because if the drug were truly spurring lethal tumors, there would have been more deaths among its users as time went on, said Dr. Michael LeFevre, a family physician at the University of Missouri.
LeFevre wrote an editorial that appears with the study in today’s New England Journal of Medicine.