Summit Therapeutics’ bispecific antibody ivonescimab failed to meet its primary overall survival endpoint in a global Phase 3 trial for non-small cell lung cancer (NSCLC), casting doubt on FDA approval prospects in the US and Europe. While progression-free survival improved significantly, overall survival benefits were confined to Asian cohorts, with Western patients showing weaker outcomes. Ivonescimab blocks PD-1 and VEGF, but the data highlight geographic variability and challenges in bispecific antibody development. The results were discussed at the 2025 World Conference on Lung Cancer. Summit acknowledged the challenges but maintained physician support for the drug’s benefits in practice.