First new drug for advanced melanoma in a decade
31 March 2011
Ipilimumab has become the first new drug to be FDA approved
for the treatment of previously treated metastatic melanoma for more
than a decade.
Ipilimumab, developed by Bristol-Myers Squibb and Medarex, is a
monoclonal antibody that consists of millions of copies of a human
antibody that binds to CTLA-4 protein molecule on T cells — white
blood cells that patrol the body for signs of illness. CTLA-4 serves
as a control switch for the immune system’s response to disease.
With no antibody attached, CTLA-4 suppresses the immune response.
Ipilimumab reverses that condition, unleashing the immune attack on
abnormal cells, including cancer cells.
“Ipilimumab is the first in a new class of drugs that has been
shown to offer a survival benefit for metastatic melanoma, which is
often a fatal disease, and hopefully, this will lead to the
development of related treatments for other cancers,” said F Stephen
Hodi, MD, director of the melanoma treatment center at Dana-Farber
Cancer Institute and a lead investigator of the national clinical
study of ipilimumab.
“While ipilimumab, on average, extended the lives of patients by
four months, there is also a group of patients who experienced a
greater benefit and lived many months while being treated with this
drug,” said Hodi. “This is a big step in the right direction because
it demonstrates that this class of drugs can benefit cancer
patients.”
In the clinical trial of the drug, about 60 percent of the
patients treated with ipilimumab experienced adverse side effects to
the therapy, as did 32 percent of the patients treated with gp100
vaccine (one of the treatment regimens in the trial). The
complications were generally immune system-related and most often
affected the skin and gastrointestinal tract. The most common
included diarrhea, nausea, constipation, fatigue, decreased
appetite, and rash. While the adverse effects could be severe and
long-lasting, most of them were reversible with appropriate
treatment.