By Fineline Cube 
China-based Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd (HKG: 6990) announced that its core product Jiatailai (sacituzumab tirumotecan, sac-TMT), a TROP2-directed antibody-drug conjugate (ADC), in combination with the PD-L1 monoclonal antibody Ketailai (tagitanlimab), has received Breakthrough Therapy Designation (BTD) from China’s Center for Drug Evaluation (CDE). This designation is for the first-line treatment of driver mutation-negative locally advanced or metastatic non-squamous non-small cell lung cancer (nsqNSCLC).
Drug Mechanism
Sacituzumab tirumotecan specifically binds to TROP2 on tumor cells, delivering the cytotoxic payload KL610023 through internalization. KL610023 induces DNA damage, cell cycle arrest, and apoptosis. Its membrane-permeable properties allow it to exert a bystander effect, enhancing antitumor activity against neighboring tumor cells. The drug features a high drug-to-antibody ratio (DAR = 7.4), contributing to its potent antitumor efficacy.
Previous Approvals and BTDs
This marks the fifth BTD granted by China’s National Medical Products Administration (NMPA) for sac-TMT. Previously, the drug received approval in China for the treatment of locally advanced or metastatic triple-negative breast cancer (TNBC) after ≥2 prior systemic therapies and EGFR mutation-positive non-squamous NSCLC progressing after EGFR-TKI therapy. Earlier BTDs were granted for TNBC, EGFR-TKI-resistant NSCLC, HR+/HER2- breast cancer, and PD-L1-negative TNBC.-Fineline Info & Tech