New Melanoma Drug May Destroy Brain Tumors

Bristol-Myers Squibb’s biotechnology drug ipilimumab, which enlists the help of the immune system to attack tumors, has shown early promise for helping patients with advanced melanoma that has spread to the brain, according to a summary of data from a mid-stage study. Ipilimumab is a monoclonal antibody, an engineered human immune system protein that boosts the body’s immune response by interfering with another immune compound called CTLA-4, which acts as a “brake” on immune system cells.

In the Phase II trial, the first to test ipilimumab in patients whose skin cancer had spread to the brain, four out of 51 patients with at least one brain lesion had a partial response to the drug, and in five out of 51 patients, both brain and other tumors in the body stabilized after 12 weeks of treatment. The responses lasted from three to 12 months, and patients had no serious toxic side effects. Data from a second study are still being evaluated.

A separate study of ipilimumab also showed signs that it could work in people who first appeared not to respond to the drug. Researchers reintroduced the drug to 32 patients who were initially treated as part of a study of 634 patients. Eight of the 32 got ipilimumab alone, 23 got ipilimumab plus a vaccine called gp100, and one got the vaccine alone. Patients whose cancer initially progressed while on ipilimumab and who were reintroduced to the drug had a disease control rate of 65 percent to 75 percent, compared with zero in the patient who got the vaccine only.