Previous studies have shown significant racial/ethnic differences in the rates of ocular diseases such as open-angle glaucoma (OAG), AMD and diabetic retinopathy (DR) among minority groups. In a new cohort study, researchers evaluated the racial/ethnic representation, trends, and disparities in clinical trials leading to FDA eye care drug approvals from 2000 to 2020.

Data was used from participants in clinical trials of drugs for AMD, OAG and DR from 2000 to 2020. Trial data was sourced from FDA reviews, ClinicalTrials.gov and relevant linked studies. National expected racial/ethnic proportions were sourced from public National Eye Institute prevalence data as well as published rates scaled using US Census Bureau data.

During the 20-year period, 31 clinical trials were identified for 13 medications with 18,410 participants. The distribution of trial participants was different from the expected trial distribution for most approvals with regard to race/ethnicity (12 drugs) and sex (10 drugs).

Compared with the first decade (2000-2010), trials conducted in the second decade (2011-2020) showed increases in enrollment of Asian and Hispanic or Latinx participants for AMD, Asian participants for DR, and Black and Hispanic/Latinx participants for OAG. There was a decrease in Black participants in DR trials. Based on these trends, the enrollment incidence ratio is expected to worsen by 2050, with overrepresentation of white participants vs.

underrepresentation of Black and Hispanic/Latinx participants in trials of drugs for

AMD (1.08 vs. 0.04 vs. 0.77), DR (1.83 vs. 0.87 vs. 0.59) and OAG (1.62 vs. 0.90 vs. 0.37).

Additionally, the authors noted how the enrollment appeared to change with increased enrollment of Asian participants in AMD and DR trials, increased Hispanic or Latinx participant enrollment in AMD and OAG trials, and increased Black participant enrollment in OAG trials. However, there was no change in enrollment of Black participants in AMD trials over time and a relative decrease in Black participants in DR trials.

“Enrollment disparity was found after accounting for the expected prevalence of disease,” the authors explained in their paper on the study. “For example, approximately 89% of US persons with AMD identify as White and at least 4% identify as Black. However, over the past 20 years, Black participants comprised 0.177% of AMD trial participants. Given that African-American individuals may be disproportionately affected by surgically treatable or preventable causes of blindness, such as cataract, glaucoma and DR, it is critical to promote equitable participation in trials for emerging therapeutics. This is especially important for diseases with strong racial/ethnic components of presentation and severity, such as OAG.”

Although there was improvement from 2000 to 2020, the authors noted further efforts to increase minority enrollment in clinical trials are warranted, and that diverse, representative enrollment in pivotal clinical trials is vital to sufficiently power subgroup analyses and ensure equity and validity of trial results.