LAUSR

Refractory or relapsing metastatic triple‐negative breast cancer (mTNBC) has a poor prognosis. Sacituzumab govitecan (SG) is a novel antibody‐drug conjugate, targeting human trophoblast cell‐surface antigen 2 (Trop‐2). This is the first report of SG's efficacy and safety in Chinese patients with mTNBC. EVER‐132‐001 (NCT04454437) was a multicenter, single‐arm, Phase IIb study in Chinese patients with mTNBC who failed ≥2 prior chemotherapy regimens. Eligible patients received 10 mg/kg SG on Days 1 and 8 of each 21‐day treatment cycle, until disease progression/unacceptable toxicity. The primary endpoint was objective response rate (ORR) assessed by the Independent Review Committee. Secondary endpoints included: duration of response (DOR), clinical benefit rate (CBR), progression‐free survival (PFS), overall survival (OS) and safety. Eighty female Chinese patients (median age 47.6 years; range 24‐69.9 years) received ≥1 SG dose with a median of 8 treatment cycles by the cutoff date (August 6, 2021). Median number of prior systemic cancer treatments was 4.0 (range 2.0‐8.0). ORR and CBR were reported 38.8% (95% confidence interval [CI]: 28.06‐50.30) and 43.8% (95% CI, 32.68‐55.30) of patients, respectively. The median PFS was 5.55 months (95% CI, 4.14‐N/A). SG‐related Grade ≥3 treatment‐emergent adverse events (TEAEs) were reported in 71.3%, the most common were neutrophil count decreased (62.5%), white blood cell count decreased (48.8%) and anemia (21.3%); 6.3% discontinued SG because of TEAEs. SG demonstrated substantial clinical activity in heavily pretreated Chinese patients with mTNBC. The observed safety profile was generally manageable.