CHICAGO, IL. – In the largest study of its kind, University of Pittsburgh Cancer Institute (UPCI) scientists have presented work of an international trial that shows that an oral molecular inhibitor therapy more than doubles survival in people who have melanoma that has progressed to the brain. The results were presented today at the American Society of Clinical Oncology annual meeting this week in Chicago.
“This new molecular inhibitor should be considered as a first-line treatment in patients with metastatic melanoma to the brain,” said John M. Kirkwood, M.D., the study’s principal investigator and professor of medicine, dermatology, and clinical and translational science at Pitt’s School of Medicine and UPCI. “It has more than doubled progression-free survival and is an oral, well-tolerated pill that is likely to revolutionize treatment of patients with this feared complication of melanoma.”
The molecular inhibitor drug, called dabrafenib, selectively binds to and inhibits the activity of the mutated BRAF protein, hindering the spread of tumor cells which contain the mutated BRAF gene. The BRAF protein is involved in sending signals to grow and spread in melanoma cells.
The study screened 325 patients, ultimately enrolling 172 of them, making it the largest study ever conducted in people with melanoma brain metastasis, or skin cancer that has spread to the brain. Brain metastases are one of the most frequent causes of death in people with melanoma. The National Cancer Institute estimates that 9,180 people will die from melanoma this year.
“This treatment helped patients live for more than seven months, while current treatments tested in our last and next-largest trial gave survivals of only three months,” Dr. Kirkwood said. “That’s never been seen before in melanoma.”
The overall survival with this treatment was 31 to 33 weeks for the two groups of previously untreated or previously treated brain metastasis, and this is more than double the average survival of nine to 14 weeks using the current chemotherapy, a drug called temozolomide. It is the only drug tested to show these results in patients with melanoma brain metastasis.
Patients participating in the study averaged 52 years old, and 70 percent were men. The majority of patients had two or more brain metastases.
In addition to the much longer survival, the melanoma brain metastases in most of the patients also stopped growing and, in one-third, shrank. Further study is needed to determine how the treatment works in the brain—and this will be addressed in a new trial that is planned for the summer.