Kelun-Biotech's sac-TMT meets primary endpoint in first-line advanced TNBC
Sichuan Kelun-Biotech announced its TROP2-directed antibody-drug conjugate, sacituzumab tirumotecan (sac-TMT), met the primary PFS endpoint in its Phase 3 OptiTROP-Breast03 trial for first-line advanced triple-negative breast cancer (https://www.prnewswire.com/news-releases/kelun-biotech-announces-phase-iii-trial-of-sacituzumab-tirumotecan-sac-tmt-versus-chemotherapy-as-firstline-treatment-for-advanced-tnbc-met-primary-endpoint-of-pfs-302779066.html). The positive data directly challenge the current standard of care in a high-need population. Global marketing applications are now anticipated.
Drug Profile
Sacituzumab tirumotecan is an antibody-drug conjugate (ADC) targeting TROP2, a cell-surface glycoprotein highly expressed in many solid tumors, including TNBC. The molecule consists of the same humanized monoclonal antibody (sacituzumab) used in Gilead's Trodelvy.
The key structural difference lies in its cytotoxic payload and linker technology. Instead of Trodelvy's SN-38 payload, sac-TMT utilizes tirumotecan, a novel and potent topoisomerase I inhibitor. This payload is attached via a proprietary, stable, enzyme-cleavable linker designed to provide a high drug-to-antibody ratio and controlled release within the tumor microenvironment, potentially offering a differentiated efficacy and safety profile.
Clinical Data
| Endpoint Name | Result | Comparator | Trial | | :--- | :--- | :--- | :--- | | Progression-Free Survival (PFS) | Met primary endpoint; statistically significant and clinically meaningful improvement reported. | Single-agent chemotherapy | OptiTROP-Breast03 |
Global Regulatory Status
Drug-specific status across all four regulatory bodies BrunoSan tracks. Separate from pipeline volume shown in the infobar.
| Regulatory Body | Status | Notes |
|---|---|---|
| Regulatory Body | Status | |
| FDA (U.S.) | No submission entry detected in BrunoSan DB as of 2026-05-22. | |
| EMA (Europe) | No submission entry detected in BrunoSan DB as of 2026-05-22. | |
| Health Canada | No submission entry detected in BrunoSan DB as of 2026-05-22. | |
| ANVISA (Brazil) | No submission entry detected in BrunoSan DB as of 2026-05-22. |
STATUS
Market Impact
This positive top-line result positions sac-TMT to directly compete in the first-line metastatic TNBC setting, a space currently dominated by chemotherapy, often in combination with checkpoint inhibitors like pembrolizumab for PD-L1 positive patients. The primary commercial competitor in the TROP2 ADC class is Gilead’s Trodelvy (sacituzumab govitecan), which holds approvals in later-line settings for TN