CHICAGO — Two new treatments, including therapy blocking a gene mutation occurring in half of melanoma patients, are prolonging lives of people suffering from the deadliest form of skin cancer, clinical trials unveiled Sunday show.
Vemurafenib neutralizes mutation of the key BRAF gene by inhibiting production of a protein which plays a major role in development of melanoma.
Users of the experimental drug were 63 percent less likely to die than people taking chemotherapy, a study showed.
The other treatment prolonging lives of those with advanced melanoma involves the anti-body ipilumumab, sold under the trade name Yervoy, which stimulates the immune system.
“The studies presented today highlight tremendous advances in the treatment of metastatic melanoma,” Lynn Schuchter, a professor of oncology at the University of Pennsylvania, told the 47th annual meeting of the American Society of Clinical Oncology (ASCO), the world’s largest oncology conference.
“Until recently we’ve had limited options for our patients, and little hope for long-term survival. In the past two years, we’ve seen remarkable progress with immunotherapy, and now, a promising targeted therapy,” she said.
Results from a phase-three international clinical trial, show that Swiss laboratory Roche’s orally administered vemurafenib — also known as PLX4032 — is the first drug to improve overall survival in patients with advanced melanoma compared to chemotherapy, the standard procedure in use since 1975.
“This is really a huge step toward personalized care in melanoma,” lead author Paul Chapman, a physician at Memorial Sloan-Kettering Cancer Center in New York, said in a statement about the findings unveiled at the conference here.
“This is the first successful melanoma treatment tailored to patients who carry a specific gene mutation in their tumor, and could eventually become one of only two drugs available that improves overall survival in advanced cancers.”
The trial involved 675 patients suffering from previously untreated, inoperable late stage metastatic melanoma and with a V600E mutation in the BRAF gene. Half were treated with vemurafenib and half with conventional chemotherapy.
After three months, patients receiving vemurafenib had a 63-percent reduction in risk of death compared to those receiving chemotherapy, and a 74-percent reduction in the risk of disease progression compared to chemotherapy, according to the study.
Also, less than 10 percent of participants treated with vemurafenib had side effects, the most common being skin irritation and joint pain.
Vemurafenib is not yet approved by the US Food and Drug Administration (FDA), a required step before the drug goes on the US market.
A phase three clinical trial unveiled last year at ASCO for Yervoy, made by pharmaceutical giant Bristol-Myers Squibb, was also highlighted Sunday.
The trial of Yervoy, approved by the FDA in March, showed that the drug taken in combination with chemotherapy significantly prolongs the life of people with advanced melanoma compared with chemotherapy alone.
Survival rate at three years was 20.8 percent for patients with Yervoy plus chemotherapy, against 12.2 percent without Yervoy.
The next step, researchers said, is to test a combination of antibodies with Yervoy and vemurafenib among patients with advanced melanoma, and a clinical trial has already begun.
According to the World Health Organization, skin cancer leads to 66,000 deaths annually worldwide, 80 percent of which involve melanomas.
More than half the patients are under age 59.