Updated overall survival (OS) results for BRIM-3, a phase III randomized, open-label, multicenter trial comparing BRAF inhibitor vemurafenib (vem) with dacarbazine (DTIC) in previously untreated patients with BRAFV600E-mutated melanoma.

Abstract

8502^ Background: We previously reported results of the planned OS interim analysis for BRIM-3 (50% of the planned 196 deaths required for final analysis) at which time the independent Data Safety Monitoring Board recommended release of results due to compelling efficacy (hazard ratio [HR] for death, 0.37 [95% CI 0.26–0.55]); p<0.0001 and PFS HR 0.26 [95% CI 0.20–0.33]; p<0.0001) and that DTIC-treated patients be permitted to cross over to receive vem. Median follow-up for vem patients was 3.75 months, and longer follow-up would estimate median OS more reliably. Updated OS with median 6.2 months follow-up and 199 total deaths showed HR for death 0.44 (95% CI 0.33–0.59) favoring vem and median OS for vem not reached. We report here the results of an updated OS analysis performed in Nov 2011 with ~10 months median follow-up on vem. Methods: 675 patients with previously untreated, unresectable Stage IIIC or IV melanoma that tested positive for BRAFV600E mutation by the cobas 4800 BRAF V600 Mutation Test were randomized (1:1) from Jan to Dec 2010 to vem (960 mg po bid) or DTIC (1000 mg/m2 IV q3w). Co-primary endpoints were OS and PFS. OS data for DTIC patients who crossed over to vem were censored at the time of crossover. Results: Median lengths of follow-up on vem and DTIC were 10.5 months (range 0.4–18.1) and 8.4 months (range <0.1–18.3), respectively. There were 334 deaths. Median OS rates with vem and DTIC were 13.2 months (95% CI 12.0–15.0) and 9.6 months (95% CI 7.9–11.8), respectively. 12-month OS rates were 55% for vem and 43% for DTIC. HR for death was 0.62 (95% CI 0.49–0.77) in favor of vem. 81 DTIC patients crossed over to vem. 44 (13%) vem and 65 (19%) DTIC patients received ipilimumab post-progression. Conclusions: With longer follow-up, vem treatment continues to be associated with improved OS in the BRIM-3 study. An updated analysis, with estimated median follow-up of ~13 months and including response data, will be conducted in Apr 2012 and presented at the meeting.