IO Biotech’s off-the-shelf cancer vaccine, Cylembio, combined with Merck’s Keytruda narrowly failed to achieve statistically significant progression-free survival in a pivotal phase 3 trial for unresectable or metastatic melanoma. Although the primary endpoint was missed by a small margin (p=0.056), encouraging trends in overall survival and subgroup analyses signal potential clinical benefit. IO plans to engage the FDA to discuss submitting an approval application, emphasizing the vaccine’s well-tolerated profile and durable effects.