(RTTNews) - Pfizer Inc. (PFE) announced detailed progression-free and overall survival results from Cohort 3 of the Phase 3 BREAKWATER trial. This randomized cohort evaluated BRAFTOVI (encorafenib) in combination with cetuximab (ERBITUX) and FOLFIRI (fluorouracil, leucovorin, and irinotecan) versus FOLFIRI with or without bevacizumab in patients with previously untreated metastatic colorectal cancer (mCRC) harboring a BRAF V600E mutation.

Cohort 3 met its primary endpoint of objective response rate (ORR) by blinded independent central review (BICR). For the key secondary endpoint of progression-free survival (PFS), median PFS was nearly doubled with the BRAFTOVI combination regimen at 15.2 months compared to 8.3 months for the comparator. Patients treated with the BRAFTOVI regimen experienced a clinically meaningful and statistically significant 56% reduction in the risk of disease progression or death versus the comparator.

Updated overall survival (OS), a descriptive secondary endpoint, showed a 44% reduction in the risk of death for patients treated with the BRAFTOVI combination regimen. With a median follow-up of approximately 20 months for both arms, 72% of patients receiving the BRAFTOVI regimen were expected to be alive at 18 months compared to 54.5% of patients on the comparator. Median OS was not reached for the BRAFTOVI regimen, while the comparator arm reported a median OS of 20.3 months.

The safety profile of BRAFTOVI in combination with cetuximab and FOLFIRI remained consistent with the known profiles of each agent, with no new safety signals identified. The most common adverse events included nausea, diarrhea, vomiting, anemia, alopecia, fatigue, decreased neutrophil count, constipation, decreased appetite, neutropenia, arthralgia, asthenia, and abdominal pain. Grade 3 or higher adverse events occurred in 70.4% of patients receiving the BRAFTOVI regimen compared to 80.9% in the comparator arm. Treatment discontinuation was reported in 15.5% of patients on the BRAFTOVI regimen versus 10.3% for those on FOLFIRI.