A new analysis of clinical trial demographics reveals a significant underrepresentation of Black women in recent triple-negative breast cancer (TNBC) studies, despite their disproportionate disease burden. The findings raise serious concerns about health equity and the generalizability of trial results to this high-risk population.
Critical Representation Gap in Clinical Trials
An examination of seven TNBC clinical trials leading to FDA approval between 2019 and 2023 found that Black women comprised only 5.4% (321/5953) of total participants. This represents less than half of the 14% benchmark that would match US census demographics, and falls dramatically short given that Black women face twice the risk of TNBC diagnosis compared to White women.
The median Black participation rate across studies was 6.5%, with an interquartile range of 4.0% to 8.3%. None of the analyzed trials came within 20% of matching the population-based target of 14.4% representation.
Worsening Trends During Pandemic
The data revealed a concerning downward trend in representation, particularly during the COVID-19 pandemic period. The most recent three trials showed Black participation dropping below 5% of the study population, reversing earlier progress toward more equitable enrollment.
Disease Burden and Mortality Impact
The representation gap is particularly troubling given that Black women face a 40% higher mortality rate from breast cancer compared to White women. While Black women have lower overall breast cancer rates, they are diagnosed with TNBC at nearly double the rate - 24.5 per 100,000 compared to 13.3 per 100,000 for White women.
Barriers to Enrollment
The study identified several key factors contributing to low enrollment:
- Limited access to tertiary medical centers conducting trials
- Geographic distribution of trial sites
- Clinical trial design and inclusion criteria
- Institutional and systemic barriers affecting diverse participation
Recommendations for Improvement
Researchers recommend multiple interventions to enhance diverse enrollment:
- Expanding inclusion criteria
- Implementing automated screening procedures
- Targeting trial sites serving diverse populations
- Providing cultural competency training for clinical staff
- Establishing community engagement resources
- Incorporating patient navigation support
Clinical Implications
The significant underrepresentation of Black women in TNBC trials raises questions about the applicability of trial results to this high-risk population. Without adequate representation, critical differences in treatment response or side effects specific to Black patients may go undetected, potentially perpetuating health disparities.
