Trial results for pembrolizumab (Keytruda) in treating patients with stage IV metastatic or recurrent inflammatory breast cancer (IBC) or triple-negative breast cancer (TNBC) were posted on ClinicalTrials.gov on 2025-07-02. The study demonstrated an efficacy of 58.1 percentage of participants and a median overall survival of 2.17 years for the treatment group.
Background
This Phase 2 trial investigated pembrolizumab as a single agent in patients with stage IV metastatic or recurrent inflammatory breast cancer or triple-negative breast cancer who had achieved clinical response or stable disease to prior chemotherapy. Pembrolizumab is an immunotherapy, a monoclonal antibody designed to help the body's immune system attack cancer and interfere with tumor cell growth and spread.
Trial design
The study, NCT02411656, was a Phase 2 trial that enrolled 71 participants. It focused on patients with stage IV metastatic or recurrent inflammatory breast cancer or triple-negative breast cancer, specifically those with conditions characterized by edema, erythema, estrogen receptor negative status, HER2/Neu negative status, and peau d'orange. The trial evaluated pembrolizumab as a single agent.
Key results
The trial reported several key measurements:
- Efficacy of pembrolizumab as a single agent in patients with metastatic IBC or non-IBC TNBC was observed in 58.1 percentage of participants in the Treatment (Pembrolizumab) group.
- Overall survival for IBC or non-IBC TNBC patients treated with pembrolizumab had a median of 2.17 years.
- Correlation between PD-L1 IHC status and overall survival:
- For PD-L1 Negative patients, the median overall survival was 26.0 months.
- For PD-L1 Positive patients, the median overall survival was 31.9 months.
- Correlation between PD-L1 IHC status and progression-free survival:
- For PD-L1 Negative patients, the median progression-free survival was 3.9 months.
- For PD-L1 Positive patients, the median progression-free survival was 5.7 months.
What this means
The results from this Phase 2 trial suggest that pembrolizumab demonstrates efficacy and contributes to overall survival in patients with stage IV metastatic or recurrent inflammatory breast cancer or triple-negative breast cancer who have responded to prior chemotherapy. The observed differences in median overall survival and progression-free survival between PD-L1 positive and PD-L1 negative patient groups indicate that PD-L1 status may serve as an important factor in predicting patient outcomes with pembrolizumab treatment in this population. These findings provide valuable insights into the potential role of pembrolizumab for these challenging breast cancer subtypes.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT02411656, titled "Pembrolizumab in Treating Patients With Stage IV Metastatic or Recurrent Inflammatory Breast Cancer or Triple-Negative Breast Cancer Who Have Achieved Clinical Response or Stable Disease to Prior Chemotherapy," were posted on 2025-07-02 on clinicaltrials.gov.