Kelun-Biotech Biopharmaceutical has announced that the Independent Data Monitoring Committee (IDMC) concluded that the phase 3 clinical study of the company’s trophoblast cell-surface antigen 2 (TROP2)-directed antibody-drug conjugate (ADC) sacituzumab tirumotecan versus investigator’s choice of chemotherapy as first-line treatment for unresectable locally recurrent or metastatic triple-negative breast cancer (TNBC), has met its primary endpoint of progression-free survival (PFS) at a prespecified interim analysis, demonstrating a statistically significant and clinically meaningful improvement. Overall survival (OS) data are immature, a positive trend is currently observed.
OptiTROP-Breast03 is a randomised, open-label, multi-centre phase 3 clinical study designed to evaluate the efficacy and safety of sacTMT 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 includes patients with programmed death ligand 1 (PD-L1)-negative expression, as well as those with PDL1-positive expression who have relapsed after prior anti-PD-(L)1 inhibitor in early stage disease.
Two independent primary endpoints of the study are PFS and OS. At this pre-specified interim analysis, sac-TMT monotherapy demonstrated a statistically significant and clinically meaningful improvement in PFS.
OS data are immature, a positive trend is currently observed. Follow-up will continue per protocol and further evaluation will be conducted in subsequent prespecified analyses. The safety profile of sac-TMT was consistent with that observed in previously reported studies, and no new safety signals were observed.
This is the first registrational phase 3 clinical study of sac-TMT to achieve positive results in the first-line treatment of TNBC. Previously, sac-TMT has been approved for the treatment of unresectable locally advanced or metastatic TNBC in patients who have received at least two prior systemic therapies (including at least one for advanced or metastatic disease) based on the results of OptiTROP-Breast01 study.
