Kelun-Biotech Biopharmaceutical Co. Ltd.’s trophoblast cell-surface antigen 2 (Trop2)-targeted antibody-drug conjugate (ADC), SKB-264, met the primary endpoint of progression-free survival (PFS) in a phase III trial in patients with unresectable locally advanced, recurrent or metastatic triple-negative breast cancer (TNBC), according to an interim analysis. The randomized, controlled, open-label, multicenter phase III trial compared injectable SKB-264 (also known as KL-A264 and MK-2870) vs. investigator-selected regimens in patients who failed second-line or above prior standard-of-care therapies.