Vemurafenib Plus Cobimetinib in BRAF -Mutant Melanoma: 5-Year BRIM7 Follow-up
Posted: Monday, March 9, 2020
In Clinical Cancer Research, the 5-year follow-up results of the phase Ib BRIM7 trial demonstrated improved survival outcomes with the combination of the BRAF inhibitor vemurafenib and the MEK inhibitor cobimetinib in a subset of patients with advanced BRAF V600–mutated melanoma. According to Antoni Ribas, MD PhD, of the University of California Los Angeles, and colleagues, “Long-term treatment achieved late conversions from partial to complete responses, and it did not result in unexpected long-term toxicities.”
A total of 129 patients with BRAF-mutant melanoma were enrolled in the study. Patients were separated into a BRAF inhibitor–naive cohort (n = 63) and a vemurafenib-monotherapy cohort (n = 66). Based on the results of the original study, the researchers chose to use two regimens for the present study: vemurafenib at 720 mg or 960 mg twice daily combined with cobimetinib at 60 mg/day for 21 days on and 7 days off.
The extended study results found that the median overall survival was 31.8 month in the BRAF-naive cohort (95% confidence interval = 24.5 months to not estimable) and 8.5 months in the vemurafenib monotherapy–progressive disease cohort (95% confidence interval = 6.7–11.1 months). Overall survival plateaued at 39.2% at 4- and 5-year follow-up in the BRAF-naive cohort, whereas in the vemurafenib monotherapy–progressive disease cohort, overall survival plateaued at 14% at 3-year follow-up.
The researchers found no new toxicities compared with the original study In addition, “there was no increase in the frequency of symptomatic MEK inhibitor class-effect adverse events,” they noted. The authors indicated the results of this follow-up suggest that a subpopulation of patients with BRAF-mutated melanoma treated with a regimen of vemurafenib and cobimetinib may obtain a positive long-term outcome.
Disclosure: For full disclosures of the study authors, visit clincancerres.aacrjournals.org.