The Results of Phase III OptiTROP-Lung05 Study of Sacituzumab Tirumotecan (sac-TMT) Presented as an ASCO Oral Presentation and Simultaneously Published in The Lancet
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. (6990.HK) has announced the results of the Phase III clinical study OptiTROP-Lung05 at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago. The study evaluated the company’s TROP2 antibody-drug conjugate (ADC) sacituzumab tirumotecan (sac-TMT), also known as SKB264/MK-2870 (佳泰莱®), in combination with pembrolizumab (KEYTRUDA®) as a first-line treatment for patients with non-small cell lung cancer (NSCLC) having a Programmed Death-Ligand 1 (PD-L1) Tumor Proportion Score (TPS) of 1% or greater. The findings were presented by Professor Caicun Zhou from Shanghai East Hospital, Tongji University, with abstract number 8506 focusing on metastatic non-small cell lung cancer.
The sac-TMT product is characterized by a distinct bifunctional linker and a differentiated payload derived from belotecan. This design aims to enhance the delivery of the therapeutic payload to cancer cells through strong attachment to the anti-TROP2 monoclonal antibody sacituzumab, coupled with pH-sensitive cleavage in the lysosome. In the study, 413 patients were randomized to receive either the sac-TMT and pembrolizumab combination or pembrolizumab alone.
As of the data cutoff date on September 29, 2025, the study reports a median follow-up of 10.5 months, indicating a significant improvement in progression-free survival (PFS) with the combination treatment compared to monotherapy. The median PFS was not reached for the sac-TMT combination versus 5.7 months for pembrolizumab alone. The 12-month PFS rates were 62.4% in the combination group compared to 29.0% in the monotherapy group. Although overall survival (OS) results were not yet mature, a positive trend was observed with a median OS not reached versus 14.5 months for pembrolizumab alone. The combination also demonstrated higher objective response rates and deep response rates than pembrolizumab alone with manageable safety profiles.
These findings have been simultaneously published in The Lancet, reflecting the clinical and academic recognition of the study's value. Professor Zhou emphasized that the positive results support the use of sac-TMT for lung cancer patients and may provide a promising option for individuals with advanced NSCLC.
Kelun-Biotech is focused on developing innovative biological and small molecule drugs, particularly within the realms of solid tumors, and has achieved multiple approvals for sac-TMT in various indications in China. The company is currently engaged in several clinical studies to further evaluate sac-TMT in combination with other cancer therapies.