iTeos, GSK end belrestotug program

iTeos Therapeutics, Inc. reported topline results from an updated interim analysis of GALAXIES Lung-201, the Phase II platform study sponsored by iTeos’ development partner GSK assessing the belrestotug + dostarlimab doublet in previously untreated, unresectable, locally advanced or metastatic PD-L1 high non-small cell lung cancer (NSCLC).

The GALAXIES Lung-201 data continued to demonstrate clinically meaningful improvements in the trial’s primary endpoint of objective response rate (ORR), however the analysis did not meet established criteria for clinically meaningful improvements in the secondary endpoint of progression free survival in the belrestotug + dostarlimab combination cohorts versus dostarlimab monotherapy. Additionally, an interim analysis of the GALAXIES H&N-202 Phase II trial showed a trend below the meaningful threshold for ORR in the belrestotug combination cohorts vs. dostarlimab monotherapy in PD-L1 positive head and neck squamous cell carcinoma.

Based on these results, iTeos and GSK have made the decision to terminate the belrestotug development program and end the collaboration. All belrestotug-containing cohorts are ending, and any new enrollment in the ongoing GALAXIES Lung-301 Phase III trial is ending. GSK is communicating with investigators, institutional review boards, ethics committees, and health authorities about next steps for appropriate management of currently enrolled patients. The Company is taking immediate steps to preserve capital and has initiated a targeted process to identify opportunities that preserve and maximize shareholder value. iTeos has engaged TD Cowen to advise on this process.