Trends in Neoadjuvant Pembrolizumab Use in Triple-Negative Breast Cancer

The addition of pembrolizumab to neoadjuvant chemotherapy (NAC) has improved treatment efficacy in triple-negative breast cancer (TNBC). The objective of this research was to investigate the national rates of NAC-pembrolizumab use for TNBC after its approval, focusing on how patient factors and socioeconomic status affected adoption.

We used the Epic Cosmos database to analyze pembrolizumab use among patients with TNBC who received NAC between 2021 and 2024. We studied how race/ethnicity and the area of deprivation index (ADI), a score of the socioeconomic designation of a region, correlated with use.

The overall rate of pembrolizumab use was 76.2% in 6689 unique patients who met the study criteria. This rate increased over time: 2021 to 35.9%, 2022 to 79.9%, 2023 to 84.1%, 2024 to 87.1%. No differences were observed in pembrolizumab use according to race or ethnicity. Patients with the highest quartile ADI scores had significantly lower rates of use than the rest of the population (74.0% vs. 77.4%, P=0.04). Investigating rates of adoption of pembrolizumab by year revealed a trend toward lower rates of use in black patients compared with white patients in 2021 (32.1% vs. 36.9%, P=0.08), and the differences according to ADI were more pronounced in earlier years.

This study revealed high rates of pembrolizumab utilization within a year of approval for its use in the treatment of TNBC. There were no significant differences in their use according to race and ethnicity, but patients who lived in areas of higher socioeconomic deprivation had lower rates of use.