Multicenter trial of neoadjuvant sacituzumab govitecan for localized triple negative breast cancer

Sacituzumab govitecan (SG), an antibody-drug conjugate targeting Trop2, is approved for pretreated metastatic triple negative breast cancer (TNBC). The multicenter NeoSTAR trial evaluated neoadjuvant SG for localized TNBC. Patients with early-stage TNBC received neoadjuvant SG for 4 cyles. The primary objective of the trial was pathological complete response in breast and lymph nodes. NeoSTAR enrolled 50 patients, of whom 49 completed 4 SG cycles. The pCR rate was 30% (95% CI 18-45) while the ORR per RECIST v1.1 was 64%. Higher Ki-67 and TILS were predictive of pCR, while baseline TROP2 expression was not. Common AEs were nausea, fatigue, alopecia, neutropenia, and rash. The 2-year event-free survival rate was 95% among all patients and 100% among the pCR patients. The authors conclude that in this first neoadjuvant trial with an antibody-drug conjugate in localized TNBC, SG demonstrated single-agent efficacy and feasibility.