IO Biotech Reveals Phase 3 Melanoma Trial Results

IO Biotech announced topline results from its pivotal Phase 3 trial evaluating its investigational cancer vaccine Cylembio in combination with Merck's KEYTRUDA (pembrolizumab) for first-line treatment of advanced melanoma. The combination therapy showed an improvement in progression-free survival (PFS) compared to pembrolizumab alone, with median PFS of 19.4 months versus 11.0 months, though the primary endpoint narrowly missed statistical significance (p=0.056). In patients without prior anti-PD-1 treatment, the combination achieved a statistically significant PFS improvement, with a median of 24.8 months versus 11.0 months, and a notable benefit was observed in patients with PD-L1 negative tumors. A trend toward improved overall survival was also reported, although data remain immature. The treatment was well tolerated with no new safety concerns, and IO Biotech plans to meet with the FDA to discuss regulatory submission next steps. The company hosted a conference call to discuss these results and emphasized its novel T-win platform designed to activate T cells against tumor and immune-suppressive cells in the tumor microenvironment.