Diversity in clinical Trials: The example of systemic lupus erythematosus

The FDA requires clinical trials to reflect real-world diversity. Systemic lupus erythematosus (SLE) is a disease that disproportionately affects individuals of Black African descent that has not been assessed for diversity in clinical trials to date. This study compared demographics from two real-world data (RWD) sources and proposes parameters for representative trial populations.

Demographics of United States (US) SLE patients were extracted from electronic health records (EHR) and registry data. These were used to model statistically representative hypothetical trial cohorts and compared with completed SLE trials using statistical tests.

Compared with both EHR and registry-derived populations, male participants were significantly underrepresented in US SLE trials (median z-score -1.04 and -0.82; P = .005; r = 0.89 for both). Asian participants were significantly underrepresented relative to registry estimates (median z-score -1.45; P = .03811; r = 0.85) but not EHR data, while Black or African American (BAA) representation was significantly higher than EHR-derived estimates (median z-score 0.97; P = .038; r = 0.69) and not significantly different from registry data. No significant differences were observed for White or Hispanic/Latino(a) populations. A SLE trial of 100 subjects would require 5-17 males, 45-65 White, 16-33 BAA, 0-7 Asian, and 4-15 Hispanic or Latino/a (HL) subjects per EHR data; or 4-16 males, 50-69 White, 22-40 BAA, and 13-29 HL subjects per registry data. Larger trials would require proportionally narrower ranges.

This study demonstrates demographic disparities in SLE trials and offers actionable benchmarks for diversity planning per FDA guidance.