The U.S. Food and Drug Administration today approved the use of
ipilimumab for the treatment of previously treated metastatic melanoma.
It is the first drug approved for metastatic, or advanced, melanoma in
more than a decade.
"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.
The number of cases of metastatic melanoma, considered to be one the
most serious form of skin cancer, has increased during the past 30
years, and its death rate is rising faster than most other cancers.
The American Cancer Society estimated that the disease was diagnosed
in more than 68,000 Americans and be responsible for 8,700 deaths in
this country in 2010.
Dr. Stephen Hodi
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
Ipilimumab reverses that condition, unleashing the immune attack on
abnormal cells, including cancer cells.
Last year, Hodi reported at the annual meeting of the American
Society of Clinical Oncology and in the New
England Journal of Medicine findings from a phase III trial
involving 676 patients with advanced (stage III or IV), inoperable
melanoma that had worsened during prior therapy for metastatic disease.
Patients were randomly assigned to receive one of three treatment
regimens: ipilimumab and the gp100 vaccine (which seeks to spark an
immune response by presenting the immune system with a protein fragment
associated with cancer); ipilimumab alone; or gp 100 alone.
The median survival period for patients receiving ipilimumab plus
gp100 was 10 months, compared with 6.4 months for those receiving gp100
alone. The median survival for participants receiving ipilimumab alone
was 10.1 months.
In the ipilimumab-alone group, nine of 15 patients continued to
benefit from the therapy for at least two years, as did four of 23
patients in the combination therapy group.
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. The complications were generally immune
system-related and most often affected the skin and gastrointestinal
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
"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."