IO Biotech says IDMC recommends continuation of IO102-IO103 trial

IO Biotech (IOBT) announced that an Independent Data Monitoring Committee recommended continuation of the company’s pivotal Phase 3 trial of its lead investigational therapeutic vaccine, IO102-IO103, following a per-protocol interim analysis. The trial is evaluating IO102-IO103 in combination with KEYTRUDA, Merck’s (MRK) anti-PD-1 therapy, as a first-line treatment for patients with unresectable or metastatic melanoma. Based on their review of the safety and efficacy data, the IDMC recommended that the trial continue without modifications and noted that no new safety signals were observed. The primary endpoint of progression-free survival is projected to be reached in the first half of 2025. The per-protocol interim analysis was performed one year after 225 patients were randomized in the trial. The interim efficacy analysis was intentionally set with a high statistical bar, and based on the analysis, the IDMC determined that the data did not meet the criteria to declare superiority of ORR. The trial was designed to preserve most of the statistical alpha for the trial’s primary endpoint of PFS. The PFS analysis is event-driven and will be conducted when 226 events have been reported in the trial with independent central review. With 407 patients randomized, the trial is powered at 89% to detect a 35% reduction in the risk of an event. “To date, none of the approved immunotherapeutic combinations for the treatment of advanced melanoma demonstrated statistical significance in ORR in large Phase 3 trials; nevertheless, these trials achieved statistical significance on PFS,” said Mai-Britt Zocca, PhD, President and CEO of IO Biotech. “Based on the 25.5 months median PFS we observed in the Phase 1/2 trial of IO102-IO103 in combination with a PD-1 inhibitor in advanced melanoma, with no added significant systemic toxicity than that typically seen with anti-PD-1 monotherapy, we remain optimistic about meeting the primary endpoint of PFS, projected to occur in the first half of 2025.”