#China #Chengdu #Lung Cancer #sacituzumab tirumotecan #OptiTROP-Lung05

Breakthrough Data Introduction

On May 29, 2026, Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. revealed groundbreaking results from the Phase III OptiTROP-Lung05 study at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting. Profound advancements in treatment for non-small cell lung cancer (NSCLC) were demonstrated, particularly for patients with a programmed death-ligand 1 (PD-L1) Tumor Proportion Score (TPS) ≥1%.

Study Overview

The study evaluated the efficacy of Sacituzumab Tirumotecan (sac-TMT) in combination with Pembrolizumab (KEYTRUDA®), a known PD-1 inhibitor. With a total of 413 patients enrolled, the trial focused on first-line treatment involving this combination versus Pembrolizumab monotherapy.

The results were striking. The median follow-up was 10.5 months, revealing progression-free survival (PFS) not reached for sac-TMT plus Pembrolizumab compared to 5.7 months in the monotherapy group, translating to a notable hazard ratio (HR) of 0.35 (95% CI 0.26-0.47; p<0.0001). The study shows compelling statistical and clinical significance that sac-TMT in tandem with Pembrolizumab significantly extends PFS.

Key Findings

PFS Benefits

The secondary analysis demonstrated consistent benefits across defined subgroups. For patients with PD-L1 TPS ≥50%, the PFS HR was found to be 0.47 (95% CI 0.29–0.77), while those with TPS 1–49% showed an HR of 0.28 (95% CI 0.19–0.41). Similarly, evaluation of tumors by histology revealed an HR of 0.28 (95% CI 0.18–0.43) in non-squamous NSCLC, and 0.44 (95% CI 0.29–0.66) in squamous NSCLC.

As for overall survival (OS), while not yet fully matured, early trends indicated a positive direction with a median OS not reached compared to 14.5 months for Pembrolizumab alone (HR = 0.55; 95% CI 0.36–0.85). Remarkably, the 12-month OS rates stood at 80.4% for the combination group versus 68.9%.

Response Rates

The data also highlighted improvements in objective response rates (ORR), showing 70.2% in the combination group against 42.0% for the monotherapy. Noteworthy was the increased deep response rate of 49.0% compared to 25.9% in monotherapy, along with a 12-month duration of response rate at 77.7% versus 59.4%.

Safety Profile

While the study reported a higher incidence of treatment-emergent adverse events (TEAEs) in the combination arm, notably due to hematologic effects associated with sac-TMT, the overall safety profile remained manageable, aligning with established safety standards of each medication involved. Crucially, no deaths linked to sac-TMT were reported.

Conclusion

The findings from the OptiTROP-Lung05 study showcase the promise of sac-TMT combined with Pembrolizumab, establishing a noteworthy improvement in PFS and demonstrating a potential new treatment pathway for patients grappling with advanced NSCLC. The research, which has also been published in The Lancet, solidifies the dual recognition of its clinical and research significance. Professor Caicun Zhou, the study's principal investigator, emphasized the importance of these findings, stressing the new treatment possibilities they open for lung cancer patients. Overall, this study stands as a beacon of hope for advancing NSCLC treatment paradigms.