Kelun-Biotech reported median overall survival 8.5 months longer with sacituzumab tirumotecan (sac-TMT) than chemotherapy among patients with advanced lung cancer after disease progressed on targeted therapy.
Kelun said the final overall-survival results were presented Oct. 25 at the European Society for Medical Oncology (ESMO) Congress. Its release identified Professor Wenfeng Fang of Sun Yat-sen University Cancer Center as the oral presenter.
The study enrolled patients with epidermal growth factor receptor (EGFR)-mutated advanced non-squamous non-small cell lung cancer whose disease progressed after EGFR tyrosine kinase inhibitor (TKI) treatment. At a median follow-up of 32.3 months, median overall survival was 25.9 months with sac-TMT and 17.4 months with platinum-based doublet chemotherapy. Kelun reported a hazard ratio for death of 0.69 (95% confidence interval, 0.54-0.89; one-sided P = 0.0021). The 24-month overall-survival rates were 54.1% and 37.2%, respectively, a difference of 16.9 percentage points.
Kelun also reported a prespecified rank-preserving structural failure time analysis to account for subsequent antibody-drug conjugate (ADC) treatment. In that adjusted analysis, median overall survival was 25.9 months with sac-TMT and 16.6 months with chemotherapy, with a hazard ratio of 0.57 (95% CI, 0.42-0.75). The company said 22.6% of patients in the chemotherapy group later received an ADC.
The company reported no new safety signals with extended follow-up. Common treatment-related adverse events included hematological events and stomatitis; Grade 3 stomatitis occurred in 4.8% of patients. Interstitial lung disease or pneumonitis was reported in one patient (0.5%) receiving sac-TMT and two (1.1%) receiving chemotherapy; all cases were Grade 1 or 2.
“For patients who progress after EGFR-TKI therapy, extended survival is an important treatment goal,” Fang said.
The study randomized 376 patients, with 188 assigned to each group. Investigators designated progression-free survival as the primary endpoint and assessed overall survival as a secondary measure within a prespecified testing hierarchy. An earlier report in the New England Journal of Medicine, based on 18.9 months of median follow-up, recorded median progression-free survival of 8.3 months with sac-TMT and 4.3 months with chemotherapy, along with an interim overall-survival hazard ratio of 0.60. The report disclosed funding from Sichuan Kelun-Biotech Biopharmaceutical.
