Disparities Between Clinical Trial Recruitment and Real-World Demographics in Macular Edema Secondary to Retinal Vein Occlusion

Abstract

Purpose

Clinical trial cohorts frequently differ demographically from the overall population receiving treatment for the condition under study. Our study describes the racial, ethnic, and gender composition of the cohorts of retinal vein occlusion (RVO) macular edema (ME) clinical trials and compares this to the racial, ethnic, and gender composition of patients undergoing treatment for ME secondary to RVO from the (Intelligent Research in Sight) IRIS Registry.

Design

Retrospective observational case series Subjects: Participants in RVO-ME clinical trials that met the following inclusion criteria: conducted in the United States of America, Phase III completed, data reported between January 1, 2000, and January 1, 2020, and demographic information reported with results.

Methods

This study identified clinical trials by searching PubMed with the following search terms; “retinal vein occlusion” and “clinical trial” and by searching ClinicalTrials.gov with the search term “retinal vein occlusion.”

Main Outcome Measures

The primary outcome was the enrollment fraction defined as the number of trial enrollees divided by the reference sample size of RVO patients undergoing treatment for ME from published IRIS Registry (Intelligent Research in Sight) data. Enrollment fraction was compared between different races, ethnicities, and genders.

Results

Eight clinical trials met our inclusion criteria. Compared to the enrollment fraction of 7.69% among Whites, lower enrollment fractions were found in Black patients (4.32%, odds ratio [OR] 0.541, confidence interval [CI] 0.468-0.626, P < .001) and Hispanic patients (3.38%, OR 0.420, CI 0.351-0.503, P < .001), and higher enrollment fraction in Asian patients (10.68%, OR 1.436, CI 1.207-1.708, P < .001). Men were more likely to enroll in the clinical trials compared to women (enrollment fraction, 7.69% vs 5.77%, respectively, OR 1.364, CI 1.273-1.462, P < .001).

Conclusions

RVO-ME clinical trials have a higher relative proportion of Asian, White and male subjects when compared to the population undergoing treatment for ME secondary to RVO. Further efforts should encourage clinical trial recruitment that is reflective of the RVO population undergoing treatment for ME to ensure generalizability of clinical trial results.