New Drug Extends Lives of Melanoma Patients
Study Shows Ipilimumab Helps Immune System Fight Deadly Skin Cancer
Ipilimumab Effective, but Not Benign
Previous research suggested that gp100 vaccine and ipilimumab act synergistically to fight tumors.
So for this study, the researchers assigned 676 patients at 125 centers around the world to one of three treatment groups: ipilimumab plus the gp100 vaccine; ipilimumab alone; or gp100 alone. All patients had failed to be helped by previous treatment.
Results showed that people who got ipilimumab alone lived an average of 10.1 months vs. 6.4 months for those who got gp100 alone. This corresponds to a 68% improvement in survival time.
"The addition of the gp100 vaccine [to ipilimumab] did not improve survival, but also did not increase side effects," O'Day says.
More importantly, 45.6% of people who took ipilimumab were alive after one year vs. 25.3% in the vaccine group, he says. At two years, the figures were 24% and 14%, respectively.
The drug, which is given as a 90-minute infusion every three weeks for four months, was hard for many patents to tolerate and even caused some deaths.
Serious immune-related reactions such as rash and colitis occurred in 10% to 15% of ipilimumab-treated patients compared with 3% on gp100 alone. Fourteen patients (2.1%) in the study died because of reactions to the treatment, seven from immune system problems.
Ipilimumab for Metastatic Melanoma
Nevertheless, melanoma doctors who heard the results here say they are enthusiastic about the new option.
"The prognosis for metastatic melanoma is really grim," says Patrick Hwu, MD, chief of the melanoma department at the University of Texas M.D. Anderson Cancer Center in Houston.
"A small subset of patients who get this drug will do well, living over five years," he says.
Since it is toxic, the challenge is to figure out which patients will benefit most, Hwu says.
Researchers are working to find biomarkers to guide treatment choices, he tells WebMD.
Doctors are most excited about the possibility of combining ipilimumab with experimental targeted drugs called BRAF inhibitors that show promise in early studies, Hwu says.
You could take the brakes off the immune system with ipilimumab and add extra gas with the BRAF inhibitors, he says.