Kelun Reports Interim Sac-TMT Lung Cancer Trial Results
Sacituzumab tirumotecan (sac-TMT) combined with pembrolizumab produced median progression-free survival of 15.0 months in the OptiTROP-Lung06 trial, compared with 5.7 months for chemotherapy combined with pembrolizumab, according to Kelun-Biotech. The findings come from a prespecified interim analysis of first-line treatment for advanced nonsquamous non-small cell lung cancer.
According to Kelun, sac-TMT is an antibody-drug conjugate targeting TROP2. Its antibody carries a topoisomerase-I-inhibitor payload. The company’s description says the conjugate attaches to TROP2 on tumor cells before entering those cells and releasing its payload.
The phase 3 trial involved 455 Chinese patients across multiple centers, Kelun said. Eligibility required a PD-L1 tumor proportion score under 1% and negative results for EGFR and ALK. Patients were randomly assigned in an open-label design to sac-TMT with pembrolizumab or to a regimen combining pembrolizumab, pemetrexed and either cisplatin or carboplatin.
Kelun’s filing gives a June 9, 2026 data cutoff; median follow-up was 9.7 months. A blinded, independent central review assessed progression-free survival, the primary endpoint. The hazard ratio for disease progression or death was 0.49, with a 95% confidence interval of 0.36–0.65 and P<0.0001. Kelun reported that this corresponded to a risk reduction of 51% for the sac-TMT regimen.
Overall survival was a secondary endpoint, and neither treatment group had reached its median at the interim analysis. Kelun stated that the overall-survival hazard ratio was 0.58, with a 95% confidence interval of 0.38–0.88. The company described this as an observed trend rather than final overall-survival findings.
For patients receiving the sac-TMT combination, Kelun reported a median response duration of 13.6 months and an objective response rate of 50.2%. The chemotherapy combination recorded corresponding results of 6.8 months and 47.3%. The response-duration hazard ratio was 0.47, with a 95% confidence interval of 0.29–0.77.
On safety, Kelun said fewer treatment-emergent adverse events reached grade 3 or above with the sac-TMT regimen. It also reported fewer adverse events requiring dose reductions or permanent discontinuation. Rates of interstitial lung disease or pneumonitis were similar across the groups, and the company said it identified no new safety signals.
According to Kelun, the October 25 presentation at the 2026 ESMO Congress in Madrid was given by Caicun Zhou of Shanghai East Hospital, Tongji University. The company also confirmed publication of the findings in The New England Journal of Medicine alongside the presentation.
In its October 13, 2026 statement, Merck said its exclusive license from Kelun-Biotech covers sac-TMT development, manufacturing and commercialization outside Greater China. Merck’s definition of that excluded territory comprises mainland China, Taiwan, Macau and Hong Kong.
* This article is based on publicly available information at the time of writing.