Pfizer (NYSE:PFE) today reported positive topline results from Cohort 3 of its pivotal Phase 3 BREAKWATER trial, marking a significant milestone in the treatment of one of the most aggressive forms of colorectal cancer.
The study evaluated BRAFTOVI® (encorafenib) in combination with cetuximab and the chemotherapy regimen FOLFIRI in patients with previously untreated metastatic colorectal cancer (mCRC) harboring the BRAF V600E mutation.
According to the data, the BRAFTOVI triple-therapy regimen demonstrated a statistically significant and clinically meaningful improvement in progression-free survival (PFS) compared to the current standard-of-care chemotherapy.
Overall survival (OS), a key secondary endpoint, also showed a "clinically meaningful prolonged improvement," according to the company.
The BRAF V600E mutation occurs in approximately 8% to 12% of metastatic colorectal cancer patients and is notoriously difficult to treat.
Cancers with this variant are often resistant to conventional chemotherapy, leading to a mortality risk more than double that of patients without the mutation.
"The combination of significant responses and now improvement in progression-free survival underscores the potential of BRAFTOVI as a potentially practice-changing treatment option," said Jeff Legos, Pfizer’s Chief Oncology Officer.
Legos noted that the targeted therapy backbone provides superior disease control, offering a crucial new pathway for patients who historically faced a poor prognosis.
The results follow a landmark December 2024 accelerated approval from the FDA, which cleared BRAFTOVI in combination with cetuximab and a different chemotherapy, mFOLFOX6, for the same patient population.
The new data from the FOLFIRI-based cohort provides clinicians with a necessary alternative, particularly for patients concerned about side effects like peripheral neuropathy often associated with FOLFOX.
Pfizer plans to share these detailed results with the FDA to support a potential supplemental approval.
If successful, the BRAFTOVI regimen would solidify its position as a cornerstone of precision medicine in oncology, fulfilling a critical unmet need in the first-line setting.
Meanwhile, the safety profile in the BREAKWATER trial remained consistent with previous studies, with no new safety signals identified. Pfizer intends to present the full dataset at an upcoming medical meeting, further bolstering its industry-leading oncology pipeline.