# Real-world use and survival outcomes of sacituzumab govitecan in metastatic triple-negative breast cancer and hormone receptor-positive/HER2-negative metastatic breast cancer

## TL;DR

This study examines how sacituzumab govitecan is used in real-world settings and its survival outcomes for patients with two types of metastatic breast cancer.

## Contribution

The study provides real-world evidence of sacituzumab govitecan's effectiveness and challenges in broader patient populations.

## Key findings

- Median overall survival was 11.0 months for mTNBC and 11.4 months for HR+/HER2–mBC patients.
- Poorer survival was linked to inpatient initiation and liver/digestive metastases.
- In mTNBC, brain metastases and multiple prior treatments were associated with worse outcomes.

## Abstract

Sacituzumab govitecan (SG) was granted early access in France as third-line therapy for metastatic triple-negative breast cancer (mTNBC) and hormone receptor-positive/HER2-negative (HR+/HER2–mBC) metastatic breast cancer. This nationwide cohort study assessed its real-world use and survival outcomes.

Using the French National Health Data System, we included all patients initiating SG between July 1, 2021, and December 31, 2023, with follow-up until June 30, 2024. Patient demographics, comorbidities, and prior treatments were recorded. Overall survival (OS) and time to treatment discontinuation (TTD) were estimated by Kaplan-Meier methods, and multivariable Cox models identified OS prognostic factors.

3653 patients were included: 2527 mTNBC and 1,126 HR+/HER2– mBC, with median ages of 58 and 61.5 years. Median OS was 11.0 months (95%CI: 10.4–11.7) for mTNBC and 11.4 months (95% CI: 10.7–12.4) for HR+/HER2–mBC. One-year survival was 47% and 48% and median TTD of 4.3 and 3.5 months, respectively. Poorer OS was independently associated with inpatient SG initiation and liver/digestive metastases. In mTNBC, additional factors included brain metastases, respiratory disease, tobacco-related hospitalisation, multiple metastatic sites, and prior treatments.

The study highlights SG’s clinical relevance and the challenge of translating trial efficacy into real-world outcomes, reinforcing the need for further investigation of tolerability in broader populations.