NMPA Accepts New Indication Application for Sacituzumab Tirumotecan (sac-TMT) as First-Line Treatment for Advanced TNBC

CHENGDU, China, July 30, 2026 /PRNewswire/ -- Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd. ("Kelun-Biotech" or the "Company", 6990.HK) announced that a new indication application of its trophoblast cell-surface antigen 2 (TROP2)-directed antibody drug conjugate (ADC) sacituzumab tirumotecan (sac-TMT, also known as SKB264/MK-2870) (佳泰莱^®) has been accepted for review by the Center for Drug Evaluation (CDE) of the National Medical Products Administration (NMPA) of China, for the first-line treatment of patients with recurrent or metastatic triple-negative breast cancer (TNBC) who have a programmed death ligand 1 (PD-L1) combined positive score (CPS) <10, or have recurred after prior programmed cell death protein 1 (PD-1)/PD-L1 inhibitor therapy in the early stage. This marks the sixth indication application accepted by the NMPA for sac-TMT.

The acceptance for review is based on the positive results from the randomized, open-label, multicenter Phase III registrational OptiTROP-Breast03 study evaluating the efficacy and safety of sac-TMT versus investigator's choice of chemotherapy in patients with unresectable recurrent or metastatic TNBC who have not received prior systemic therapy for advanced disease. The enrolled population included patients with PD-L1 CPS <10, as well as those who have recurred after prior PD-1/PD-L1 inhibitor therapy in the early stage. The study demonstrated that sac-TMT achieved statistically significant and clinically meaningful improvements in key efficacy profile compared with investigator's choice of chemotherapy, showing a clear clinical benefit.

Previously, sac-TMT was granted Breakthrough Therapy Designation (BTD) by the NMPA for the first-line treatment of unresectable locally advanced, recurrent or metastatic PD-L1-negative TNBC. This new indication application has also been included in the priority review and approval process, becoming the sixth application for sac-TMT to enter this process. Inclusion in this process is expected to further expedite the review and approval, allowing this innovative treatment to benefit patients sooner. 

Dr. Michael Ge, CEO of Kelun-Biotech, said, "Following the approval of sac-TMT for second-line or later treatment of TNBC based on results from the Phase III OptiTROP-Breast01 study, we are delighted to see another important milestone in the same disease area. For patients with PD-L1-negative advanced TNBC, the efficacy of traditional chemotherapy is limited, and there is an urgent clinical need for more effective and safer first-line treatment options. The positive results from the OptiTROP-Breast03 study demonstrate a clear and clinically meaningful improvement in efficacy with sac-TMT compared to chemotherapy and support the continued evaluation of sac-TMT as the first-line treatment for TNBC. We look forward to the early approval of this indication to bring a new and more effective first‑line treatment option to a broader population with advanced TNBC."

About sac-TMT(佳泰莱^®)

Sac-TMT, a core product of the Company, is a novel human TROP2 ADC in which the Company has proprietary intellectual property rights, targeting advanced solid tumors such as non-small cell lung cancer (NSCLC), breast cancer (BC), gastric cancer (GC), gynecological tumors and genitourinary tumors, among others. Sac-TMT is developed with a unique, bifunctional linker that maximizes payload delivery to tumor cells both through its irreversible connection with the anti-TROP2 monoclonal antibody sacituzumab and its pH-sensitive cleavage from a belotecan-derivative topoisomerase I inhibitor payload in the lysosome, with a drug-to-antibody-ratio (DAR) of 7.4. Sac-TMT specifically recognizes TROP2 on the surface of tumor cells by recombinant anti-TROP2 humanized monoclonal antibodies, which is then endocytosed by tumor cells and releases the payload KL610023 intracellularly. KL610023, as a topoisomerase I inhibitor, induces DNA damage to tumor cells, which in turn leads to cell-cycle arrest and apoptosis. In addition, it also releases KL610023 in the tumor microenvironment. Given that KL610023 is membrane permeable, it can enable a bystander effect, or in other words kill adjacent tumor cells.

In May 2022, the Company licensed the exclusive rights to MSD (the tradename of Merck & Co., Inc, Rahway, NJ, USA) to develop, use, manufacture and commercialize sac-TMT in all territories outside of Greater China (which includes Mainland China, Hong Kong, Macao and Taiwan).

To date, four indications for sac-TMT have been approved and marketed in China for: 1) unresectable locally advanced or metastatic TNBC who have received at least two prior systemic therapies (at least one of them for advanced or metastatic setting); 2) epidermal growth factor receptor (EGFR) mutant-positive locally advanced or metastatic non-squamous NSCLC following progression on epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) therapy and platinum-based chemotherapy; 3) EGFR mutant-positive locally advanced or metastatic non-squamous NSCLC who progressed after treatment with EGFR-TKI therapy; 4) unresectable or metastatic hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) (Immunohistochemistry (IHC) 0, IHC 1+ or IHC 2+/In Situ Hybridization (ISH)-) BC who have received prior endocrine therapy and at least one line of chemotherapy in advanced setting. The first two indications above have been included in China's National Reimbursement Drug List (NRDL). This inclusion is expected to bring clinically meaningful benefits to a greater number of patients with BC and NSCLC. Additionally, sac-TMT has been granted six BTDs by the NMPA.

Sac-TMT is the world's first TROP2 ADC drug approved for marketing in lung cancer.  Two new indication applications have been accepted for review by the NMPA and have been included in the priority review and approval process: 1)  sac-TMT in combination with pembrolizumab (KEYTRUDA^®[1]) as first‑line treatment for locally advanced or metastatic NSCLC who have PD-L1 tumor proportion score (TPS)≥1% and are EGFR-negative and anaplastic lymphoma kinase (ALK)-negative; and 2) sac‑TMT as first‑line treatment for patients with recurrent or metastatic TNBC who have a PD‑L1 CPS <10 or have recurred after prior PD‑1/PD‑L1 inhibitor therapy in the early stage. As of today, Kelun-Biotech has initiated 9 registrational clinical studies in China. MSD has initiated 17 ongoing global Phase III clinical studies of sac-TMT as a monotherapy or in combination with pembrolizumab or other anti-cancer agents for several types of cancer. These studies are sponsored and led by MSD.

About Kelun-Biotech

Kelun-Biotech (6990.HK) is a holding subsidiary of Kelun Pharmaceutical, which focuses on the R&D, manufacturing, commercialization and global collaboration of innovative biological drugs and small molecule drugs. Kelun-Biotech focuses on major disease areas such as solid tumors, autoimmune, and metabolic diseases, and in establishing a globalized drug development and industrialization platform to address the unmet medical needs in China and the rest of world. Kelun-Biotech is committed to becoming a leading global enterprise in the field of innovative drugs. At present, Kelun-Biotech has more than 30 ongoing key innovative drug projects, of which 4 projects with 8 indications have been approved for marketing, 2 projects with 3 indications are in the NDA stage and more than 10 projects are in the clinical stage. Kelun-Biotech has established one of the world's leading proprietary ADC and novel DC platforms, OptiDC™, and has 2 ADC projects with 5 indications approved for marketing, and multiple ADC and novel DC assets in clinical or preclinical research stage. For more information, please visit https://en.kelun-biotech.com/.

 

source: Kelun-Biotech