The Efficacy and Safety of Sacituzumab Govitecan in Heavily Pretreated Metastatic Triple-Negative and Hormone Receptor-Positive/HER2-Negative Breast Cancer: A Multicenter Real-World Study from Turkey

Background/Objectives: Sacituzumab govitecan (SG) is an antibody-drug conjugate targeting Trop-2, approved for use in metastatic triple-negative breast cancer (mTNBC) and more recently in hormone receptor-positive/HER2-negative (mHRPBC) subtypes. While clinical trials have demonstrated its efficacy, real-world da-ta—especially involving both molecular subtypes—remain scarce. This multicenter, retrospective study aimed to evaluate the real-life effectiveness, safety, and prognostic factors associated with SG treatment in patients with both mTNBC and mHRPBC. Methods: A total of 68 patients treated with SG between 2022 and 2025 were included from multiple oncology centers in Turkey. Patients with mTNBC were required to have received at least one prior chemotherapy line, while mHRPBC patients had received at least two prior chemotherapy lines in addition to hormone therapy. Clinical out-comes—including progression-free survival (PFS), overall survival (OS), and objective response rate (ORR)—were evaluated. Univariate and multivariate analyses were performed to identify factors influencing outcomes. Adverse events (AEs) were also documented and graded according to NCI-CTCAE v5.0. Results: The cohort included 35 (51.5%) mTNBC and 33 (48.5%) mHRPBC patients. The median PFS was 6.1 months, and the median OS was 12.5 months, with no significant differences between subtypes. The ORR was 52.9%, with a complete response observed in 10.3% of patients. Eastern cooperative oncology group performance status (ECOG PS) and liver metastasis were independent predictors of poorer PFS and OS. Prior immunotherapy did not negatively impact SG efficacy. SG was generally well tolerated; the most common AEs were alo-pecia, anemia, neutropenia, and diarrhea. Treatment discontinuation due to AEs was rare (2.9%). Conclusions: SG demonstrated comparable effectiveness and a managea-ble safety profile in real-world patients with both mTNBC and mHRPBC. Importantly, this study provides one of the first real-world datasets evaluating SG in the mHRPBC subgroup, highlighting its potential role beyond clinical trials. These results support SG as a valuable therapeutic option in heavily pretreated patients, warranting further prospective and biomarker-driven studies.