New Hope in GIST: PEAK Trial Advances Second-Line Treatment

In an interview on-site at the 2026 ASCO Annual Meeting, Andrew J. Wagner, MD, PhD, of Dana-Farber Cancer Institute, discusses the phase 3 PEAK trial (NCT05208047), which evaluated the investigational KIT inhibitor bezuclastinib in combination with sunitinib (Sutent) for patients with advanced gastrointestinal stromal tumors (GIST) previously treated with imatinib (Gleevec).

Wagner explains how resistance mutations can limit the effectiveness of second-line therapy and describes the scientific rationale for pairing sunitinib with bezuclastinib, an investigational agent designed to target additional KIT mutations not adequately addressed by standard treatment alone. He reviews the study's primary findings, including a median progression-free survival of 16 months with the combination compared with 9 months for sunitinib monotherapy, representing a meaningful reduction in the risk of progression or death.

Beyond the efficacy data, Wagner discusses why the results are particularly notable in the GIST treatment landscape, where demonstrating superiority over an active comparator has historically been challenging. He also shares updates on the regulatory status of the regimen, including the FDA's recent acceptance of the new drug application under priority review, and highlights the availability of an expanded access program that may provide eligible patients with access to the combination while regulatory review is ongoing.