PD-1 MOUNTAINEER: Open-label, phase 2 study of tucatinib combined with trastuzumab for HER2-positive metastatic colorectal cancer (SGNTUC-017, trial in progress)

Abstract

The clinical benefit of approved therapies in patients (pts) with metastatic colorectal cancer (mCRC) who progress on first- and second-line chemotherapy (FOLFOX and FOLFIRI) is limited. In pts with chemotherapy-refractory RAS wild type mCRC, antibodies targeting EGFR offer a monotherapy response rate of approximately 20% and a progression-free survival (PFS) of 4 months (Price 2014). HER2 is a validated target in gastric and breast cancers, with HER2 amplification occurring in ∼3–5% of pts with mCRC.