Two B7-H3-directed antibody-drug conjugates—tambotatug pelitecan (tam-peli; YL-201) and risvutatug rezetecan (ris-rez)—met overall survival primary endpoints in China-based phase 3 trials in advanced small-cell lung cancer (SCLC). The reported hazard ratios were identical across the two studies, supporting an emerging read on the clinical tractability of B7-H3 ADCs in the relapsed setting. The TAISHAN-302 trial for tam-peli vs. topotecan reported a 54% reduction in risk of death (median OS 13.3 vs. 9.4 months; p<0.0001) alongside improved progression-free survival and response rates. In parallel, the ris-rez study also achieved its OS endpoint in its China population, strengthening the case for a B7-H3 ADC class signal rather than a single-asset anomaly. For industry watchers, the key implication is that SCLC—traditionally hard to treat after initial immunotherapy and platinum—may see a refreshed sequencing landscape as these data mature for global development. The other watch item is regulatory translation outside China, where global sponsors will need to map these efficacy signals to comparable patient selection and standard-of-care comparators.