A secondary analysis of the Phase 3 KEYNOTE-716 trial, published in JAMA Network, shows that adjuvant pembrolizumab continues to provide strong benefits for patients with resected stage IIB or IIC melanoma. The treatment significantly improved recurrence-free survival, with a 48-month rate of 68.7% compared to 56.5% for placebo.
The study also found that immunotherapy did not increase the risk of developing new primary cancers. In fact, non-melanoma skin cancers were more common in the placebo group. During follow-up, 7.6% of patients receiving pembrolizumab developed a new skin cancer, compared to 11.5% in the placebo group.
Although pembrolizumab was linked to more immune-related side effects, these were generally manageable. Severe skin reactions occurred in a small percentage of patients and most cases resolved, with very few patients needing to stop treatment.
Overall, the results confirm that pembrolizumab helps delay melanoma recurrence without raising the risk of secondary cancers, though continued skin monitoring remains important for all patients.