NEW YORK – Erasca on Wednesday said it has partnered with Pfizer on a trial evaluating its ERK1/2 inhibitor ERAS-007 with Pfizer's encorafenib (Braftovi) and Eli Lilly's cetuximab (Erbitux) for metastatic, BRAF V600E-mutated colorectal cancer.
San Diego-based Erasca will sponsor the Phase Ib/II trial, dubbed HERKULES-3, while Pfizer will supply its BRAF inhibitor encorafenib, and the two companies will team up on a joint development committee to review the data. The companies are exploring the activity of the combination regimen based on the hypothesis that the agents will work together to simultaneously inhibit upstream EGFR signaling, midstream BRAF signaling, and downstream ERK signaling in the RAS/MAPK pathway.
Clinical trial results have shown that the majority of patients develop resistance to the combination of encorafenib and cetuximab, dampening the long-term benefit of a regimen that has been available in the US for BRAF V600E-mutated metastatic colorectal cancer since April 2020. Adding Erasca's ERK inhibitor to the regimen, the firms hope, will hinder one of the resistance mechanisms and improve survival.
Erasca and Pfizer expect the study will begin during the second half of this year.