IO Biotech announced that it has randomized 225 patients in its global Phase 3 clinical trial for IO102-IO103, in combination with KEYTRUDA (pembrolizumab), Merck's anti-PD-1 therapy, in patients with advanced melanoma. This clinical milestone is significant as the Phase 3 trial protocol calls for an interim analysis of overall response rate one year after 225 patients have been enrolled. Data obtained from this interim analysis, if positive, could allow for submission of a Biologics License Application for an accelerated approval in the United States.

Additionally, the company announced that it is increasing the number of patients to be enrolled in the Phase 3 trial to 380 patients, which could potentially accelerate the time to reach the primary end point of progression free survival. If the data are supportive, the PFS endpoint would serve as the basis for submitting marketing applications on a global basis. IO102-IO103 is an investigational immune-modulating cancer vaccine designed to target the immunosuppressive mechanisms mediated by the key immunosuppressive proteins indoleamine 2,3-dioxygenase (IDO) and PD-L1.

IOB-013/KN-D18 (Clinical Trials.gov: NCT05155254) is an open label, randomized Phase 3 clinical trial of IO102-IO103 in combination with pembrolizumab versus pembrolizumab alone in patients with previously untreated, unresectable or metastatic (advanced) melanoma, being conducted in collaboration with Merck. Target enrollment is 380 patients from centers spread across the United States, Europe, Australia, Israel and South Africa. Biomarker analyses will also be conducted.

IO Biotech is sponsoring the Phase 3 trial and Merck is supplying pembrolizumab. IO Biotech maintains global commercial rights to IO102-IO103.