By Alissa Greenberg

However, the associated side-effects of the dual treatment are amplified

Two cancer drugs, when taken in concert, can shrink tumors in nearly 60% of people with advanced-stage melanoma, according to a new study.

The trial, which enrolled 945 patients at 137 sites worldwide, found that treating the cancer with medications ipilimumab and nivolumab stopped its advance for almost a year in more than half of cases.

Both drugs are designed to bring the body’s natural defenses in on the fight against the cancer. While the immune system is generally a potent agent in combatting disease, certain built-in “brakes” keep the body from attacking its own tissue — a loophole that cancers can use to continue growing unchecked. But both medications turn those “brakes” off.

In the study, 58% of patients taking both medicines saw their tumours shrink by at least a third over the course of almost a year. Still, perhaps the most important information — how long patients treated with the two medications live — is unknown, and will remain so for some time.

Skin cancer is among the most common cancers, while melanoma accounts for less than 2% of skin cancers, it causes the majority of skin cancer deaths. It has been predicted that nearly 10,000 Americans will die of skin cancer in 2015.