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, the BBC reports, citing a presentation by U.K. doctors this weekend at the American Society of Clinical Oncology annual conference.

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; according to the American Cancer Society (ACS), while melanoma accounts for less than 2% of skin cancers, it causes the majority of skin cancer deaths. The ACS predicts that nearly 10,000 Americans will die of skin cancer in 2015.

[BBC]

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