ASCO 2026 & The Lancet: OptiTROP-Lung05 Phase 3 — Sacituzumab Tirumotecan + Pembrolizumab Reduces Lung Cancer Progression by 65% vs. Pembrolizumab Alone

Phase 3 OptiTROP-Lung05 results, presented as an oral abstract at ASCO 2026 and simultaneously published in The Lancet, demonstrated that sacituzumab tirumotecan (sac-TMT; SKB264) combined with pembrolizumab achieves a 65% reduction in the risk of progression or death versus pembrolizumab monotherapy in the first-line treatment of PD-L1-positive (TPS ≥1%) advanced non-small cell lung cancer (NSCLC). The trial enrolled 413 patients randomized 1:1. Median PFS was not reached with sac-TMT + pembrolizumab versus 5.7 months with pembrolizumab alone (HR 0.35 [95% CI: 0.26–0.47]; p<0.0001). Twelve-month PFS rates were 62.4% vs. 29.0%. The objective response rate was 70.2% vs. 42.0%, and deep response rates were 49.0% vs. 25.9%. Overall survival data showed a favorable trend: 12-month OS 80.4% vs. 68.9% (HR 0.55; p not yet mature). Sacituzumab tirumotecan is a TROP2-targeting antibody-drug conjugate developed by Kelun-Biotech (China) in partnership with Merck, using a novel topoisomerase I inhibitor payload. This is the first Phase 3 trial to demonstrate that an ADC + IO combination significantly outperforms pembrolizumab monotherapy in first-line PD-L1+ NSCLC — a major patient population (~50% of all advanced NSCLC). The result marks a defining moment for Asian pharma innovation and the TROP2-ADC drug class, which has now proven its value across multiple solid tumor types. Prof. Caicun Zhou (Shanghai East Hospital/Tongji University) presented the data.