Trial results for a study evaluating Pembrolizumab (Keytruda) in combination with Sacituzumab Govitecan for HR+/HER2- metastatic breast cancer were posted on ClinicalTrials.gov on 2025-05-30. The combination arm demonstrated a median progression-free survival of 8.36 months, compared to 6.45 months for sacituzumab govitecan alone.
Background
Metastatic HR+/HER2- breast cancer is an advanced form of breast cancer that has spread beyond the breast and is hormone receptor-positive and HER2-negative. Treatment options for this patient population are continually being explored to improve outcomes.
Trial design
This Phase 2 study (NCT04448886) enrolled 110 participants with Invasive Breast Cancer, Metastatic Breast Cancer, HR-Positive Breast Cancer, and HER2-negative Breast Cancer. The trial investigated the safety and effectiveness of Sacituzumab Govitecan with or without Pembrolizumab.
Key results
Key outcome measurements from the trial include:
- For Progression Free Survival, the median was 8.36 months for the Sacituzumab Govitecan + Pembrolizumab group, compared to 6.45 months for the Sacituzumab Govitecan group.
- The Objective Response Rate was observed in 15 participants in the Sacituzumab Govitecan + Pembrolizumab group and 10 participants in the Sacituzumab Govitecan group.
- Median Overall Survival was 20.0 months (95% Confidence Interval) for the Sacituzumab Govitecan + Pembrolizumab group, versus 18.0 months (95% Confidence Interval) for the Sacituzumab Govitecan group.
- The Clinical Benefit Rate was observed in 26 participants for both the Sacituzumab Govitecan + Pembrolizumab group and the Sacituzumab Govitecan group.
- Median Time to Progression was 8.36 months (95% Confidence Interval) for the Sacituzumab Govitecan + Pembrolizumab group, and 6.68 months (95% Confidence Interval) for the Sacituzumab Govitecan group.
- The median Duration of Response was 12.93 months (Full Range) for the Sacituzumab Govitecan + Pembrolizumab group, compared to 4.51 months (Full Range) for the Sacituzumab Govitecan group.
What this means
The results suggest that adding Pembrolizumab to Sacituzumab Govitecan may enhance efficacy in patients with HR+/HER2- metastatic breast cancer. The observed improvements in median progression-free survival, objective response rate, overall survival, time to progression, and duration of response in the combination arm indicate a potential clinical benefit. These findings warrant further investigation in larger studies.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT04448886, titled "Sacituzumab Govitecan +/- Pembrolizumab In HR+ / HER2 - MBC," were posted on 2025-05-30 on clinicaltrials.gov.