Merck & Kelun-Biotech: Sac-TMT Achieves Triple Phase 3 Success Merck and Kelun-Biotech announced triple Phase 3 wins. Sacituzumab tirumotecan (sac-TMT) met primary endpoints. OptiTROP-Breast03 showed strong PFS. This ADC targets advanced TNBC. Merck and Kelun-Biotech's sac-TMT achieved positive Phase 3 results across three studies. The OptiTROP-Breast03 trial, a pivotal study, met its primary endpoint of progression-free survival (PFS). This success positions sac-TMT as a potential first-line treatment for advanced triple-negative breast cancer (TNBC), a difficult-to-treat malignancy. The specific metric triggering this event was a statistically significant improvement in PFS. This positive outcome paves the way for regulatory submissions. Under FDA guidelines, these results support a New Drug Application (NDA) or Biologics License Application (BLA). EMA approval will also be sought. The companies will now compile comprehensive data packages for review. This process adheres to 21 CFR Part 314 for NDAs or Part 601 for BLAs. Expedited review pathways may be pursued given the unmet need in TNBC. This triple win boosts Merck and Kelun-Biotech's oncology pipeline. Sac-TMT could challenge existing TNBC treatments like Gilead's Trodelvy (sacituzumab govitecan). This success validates the antibody-drug conjugate (ADC) platform. Competitors like AstraZeneca/Daiichi Sankyo's Enhertu (trastuzumab deruxtecan) also operate in the ADC space. Expect regulatory filings to commence by Q4 2026.