Dr Somaiah on the Peak Trial in GIST

Neeta Somaiah, MD, associate professor, deputy department chair, Department of Sarcoma Medical Oncology, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, discusses enrollment criteria for the phase 3 Peak trial (NCT05208047) in patients with gastrointestinal stromal tumor (GIST) and the advantages of this trial’s design.

The Peak trial is investigating bezuclastinib (CGT9486) in combination with sunitinib (Sutent) vs sunitinib alone in patients with GIST. The first portion of part 1 of this trial enrolled patients who had received at least 1 prior line of therapy for GIST. The second evaluation of part 1 enrolled patients who had received at least 2 prior TKIs for GIST. Part 2 of this trial is enrolling patients who progressed on or are intolerant to imatinib.

Many patients with GIST receive imatinib (Gleevec) in the first line and may switch to local treatment options upon local progression, Somaiah says. Patients who progress with more diffuse disease may be eligible for enrollment in the Peak trial, Somaiah notes. GIST is a relatively easier-to-treat sarcoma because it has standard first-, second-, third-, and fourth-line therapeutic options, which patients may be referred to upon progression on imatinib, according to Somaiah. However, community oncologists should consider the Peak trial before prescribing standard lines of therapy beyond imatinib. Patients with GIST who receive treatment beyond imatinib are not eligible for enrollment in Peak and lose the chance to receive an additional line of targeted therapy, Somaiah emphasizes.

Data from part 1 of Peak, which were presented at the 2023 ASCO Annual Meeting, showed that bezuclastinib plus sunitinib was well tolerated, Somaiah notes. The safety profile of this combination supports further enrollment in this trial, Somaiah says.

Additionally, even patients in the Peak trial who are not randomly assigned to receive the investigative combination will receive sunitinib monotherapy in the control arm, Somaiah explains. This trial is distinct from placebo-controlled trials because it offers patients standard benefits in both arms, Somaiah emphasizes. Furthermore, patients who are randomly assigned to receive sunitinib monotherapy may have the option of crossing over to the investigative arm upon disease progression, Somaiah notes. Raising awareness about the advantages of this second-line trial can help more patients access a potentially beneficial treatment combination, Somaiah concludes.