Hansoh Pharmaceutical’s B7-H3 antibody-drug conjugate risvutatug rezetecan (ris-rez), partnered with GSK, cleared its Phase 3 primary endpoint in China by improving overall survival in advanced or relapsed small-cell lung cancer. The companies described the readout as the first positive Phase 3 overall survival data for a B7-H3-targeted ADC in any tumor type. GSK will use the Phase 3 result to support an approval push in China, while the companies continue development of additional ris-rez studies in other indications. The trial’s lack of disclosed granular statistics in the release still leaves room for investors to watch follow-on efficacy and safety details at scientific meetings and during regulatory review. Clinically, the reported OS benefit strengthens the case for B7-H3 as an actionable target in SCLC and potentially expands ADC strategy beyond traditional targets.