Adding to this week's news about progress in the treatment of melanoma, a vaccine for the deadly skin cancer has shown promise in a new study.
Melanoma is the most serious type of skin cancer. The five year-survival rates for local and metastatic melanoma are 65% and 16%, respectively. In 2009, an estimated 69,000 people in the United States will be diagnosed with melanoma and about 8,600 will die of the disease, according to the American Cancer Society.
The study, a phase 3 clinical trial involving 185 people, found that using the peptide vaccine in combination with the immunotherapy drug Interleukin-2 improved response rates and progression-free survival, according to University of Texas M.D. Anderson Cancer Center researchers, who said it was the first phase 3 trial to show a clinical benefit in a vaccine for melanoma.
Response rate and progression-free survival were 22.1% and 2.9 months, respectively, in people given the vaccine, compared with 9.7% and 1.6 months for those who were not vaccinated. Median overall survival was 17.6 months for the vaccine group and 12.8 months for the others.
The study, which was to be presented at the annual meeting of the American Society of Clinical Oncology in Orlando, Florida, was funded in part by Novartis, which makes Interleukin-2. "Obviously this is a disease, in its advanced setting, in need of better therapies for our patients," study co-author Dr. Patrick Hwu, a professor and chairman of M.D. Anderson's Department of Melanoma Medical Oncology, said in a news release from the center. "While more follow-up is needed, this study serves as a proof-of-principle for vaccines' role in melanoma and in cancer therapy overall. If we can use the body's own defense system to attack tumor cells, we provide a mechanism for ridding the body of cancer without destroying healthy tissue."
The vaccine, called gp100:209-217 (200M), works by stimulating T-cells, which control immune response. "This vaccine activates the body's cytotoxic T-cells to recognize antigens on the surface of the tumor," Hwu said. "The T-cells then secrete enzymes that poke holes in the tumor cell's membrane, causing it to disintegrate."
The Skin Cancer Foundation has more about melanoma.
HealthDay News, May 30, 2009