So if a melanoma patient has a BRAF mutation and needs targeted therapy to treat their cancer, they may receive a BRAF inhibitor drug, such as dabrafenib, plus a MEK inhibitor drug, such as trametinib — since combining those drugs appears to work better than using either one alone.
The new study involved analyzing data from two previous trials that assessed adult melanoma patients who were treated with dabrafenib and trametinib. Dabrafenib is sold as the brand name Tafinlar and trametinib is sold as the brand name Mekinist.
That data included 563 patients who were randomly assigned to receive dabrafenib twice daily plus trametinib once daily. Pharmaceutical company GlaxoSmith-Kline sponsored the two trials.
By five years after first-line treatment with dabrafenib plus trametinib, the researchers found that 19% of the patients were progression-free and the overall survival rate was 34%.
By comparison, in the dabrafenib-plus-placebo group and in the vemurafenib group, the five-year overall survival rate was 27% and 23%, respectively.
“While metastatic melanoma has historically had a very poor prognosis for patients, there are many reasons to be encouraged today. Our analysis demonstrates a clinically meaningful and positive impact on patient survival. These results show that targeted therapies may provide long-term survival and offer durable outcomes,” she said.
Some adverse events led to patients discontinuing the trial, which included fever, decreased pumping of blood in the heart, and increased levels of a certain enzyme in the liver and kidneys.
“This study is well done and suggests that patients expressing the markers are more likely to benefit from the two targeted therapies in combination as a first treatment instead of the immunotherapy. It clarifies the question mark,” Brawley said.
“There is a second finding — the longer people survived the fewer relapsed. This suggests that a small proportion of these patients are cured of melanoma,” he said. “We in medical oncology are hesitant to use the word cure when talking about metastatic solid tumors but the fact that the long-term survival curves flatten is extremely encouraging.”