Chengdu, China, October 25, 2026
Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. announced positive results from the Phase 3 OptiTROP-Lung06 clinical trial, evaluating sacituzumab tirumotecan (sac-TMT) in combination with pembrolizumab as first-line treatment for patients with PD-L1-negative advanced non-squamous non-small cell lung cancer (NSCLC). The findings showed that the investigational antibody-drug conjugate combination significantly improved progression-free survival (PFS) compared with platinum-based doublet chemotherapy plus pembrolizumab. Median PFS reached 15.0 months with sac-TMT plus pembrolizumab, compared with 5.7 months in the chemotherapy-based control group. The results were presented as an oral presentation at the 2026 European Society for Medical Oncology (ESMO) Congress in Madrid, Spain, and simultaneously published in The New England Journal of Medicine. The findings add to clinical research into targeted antibody-drug conjugates for advanced lung cancer, particularly among patients whose tumours lack targetable genomic alterations and do not express PD-L1.
OptiTROP-Lung06 Shows Longer Progression-Free Survival
The randomized Phase 3 OptiTROP-Lung06 study enrolled 455 patients with previously untreated, advanced non-squamous NSCLC that was PD-L1-negative and lacked targetable genomic alterations. Participants were assigned to receive sac-TMT plus pembrolizumab or platinum-based doublet chemotherapy plus pembrolizumab. After a median follow-up of 9.7 months, blinded independent central review showed that the sac-TMT combination reduced the risk of disease progression or death by 51%, with a hazard ratio of 0.49 and a p-value below 0.001. Median PFS was 15.0 months in the investigational treatment group and 5.7 months in the control group. The estimated 12-month PFS rates were 51.1% and 22.8%, respectively. These results demonstrate a statistically significant improvement in the trial’s primary efficacy measure. However, overall survival data were immature at this interim analysis. Although the hazard ratio for death was 0.58, the median overall survival had not been reached in either group, meaning longer follow-up is needed to determine whether the combination improves overall survival.
Response Durability and Safety Findings
The objective response rate was 50.2% with sac-TMT plus pembrolizumab, compared with 47.3% with chemotherapy plus pembrolizumab. Although the overall response rates were similar, deeper tumour responses were more frequent with the investigational combination: 28.8% of patients achieved a deep response, compared with 17.3% in the control group. Median duration of response was 13.6 months versus 6.8 months, respectively. These findings suggest that responses in the sac-TMT group were more durable, even though the proportion of patients achieving an objective response was comparable. The reported safety profile was generally consistent with the known effects of the individual treatments, and no new safety signals were observed. Grade 3 or higher treatment-emergent adverse events occurred in 47.6% of patients receiving sac-TMT plus pembrolizumab, compared with 60.6% in the chemotherapy-based group. Stomatitis, or inflammation of the mouth, was common with sac-TMT but was predominantly Grade 1 or Grade 2. The incidence of interstitial lung disease or pneumonitis was similar between the treatment groups. These safety results will be important in assessing the combination’s overall benefit-risk profile as clinical development continues.
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Sac-TMT Advances Targeted Treatment Research in NSCLC
Sacituzumab tirumotecan, also known as sac-TMT, SKB264 or MK-2870, is a TROP2-targeted antibody-drug conjugate being developed to deliver a cytotoxic payload to cancer cells expressing TROP2. The antibody component recognizes the target on tumour cells, while the linked drug payload is designed to disrupt cancer-cell survival. Pembrolizumab is an immune checkpoint inhibitor that blocks PD-1, helping restore the immune system’s ability to recognize and attack cancer cells. The combination brings together targeted delivery of an anticancer agent and immunotherapy. Kelun-Biotech is developing sac-TMT across multiple cancer settings, including lung cancer. The OptiTROP-Lung06 findings are relevant because PD-L1-negative advanced NSCLC remains a challenging treatment population, particularly when patients do not have genomic alterations that can be addressed with other targeted therapies. The results support further evaluation of sac-TMT plus pembrolizumab, but do not yet establish an overall survival advantage. Additional follow-up and regulatory assessment will be necessary to clarify the treatment’s long-term benefits and its potential role in first-line care.
Source: Kelun-Biotech press release
