# Racial and Ethnic Diversity in Clinical Trials for Disease Modifying Drugs in Parkinson Disease: A Systematic Review & Meta-Analysis

## TL;DR

This study finds that non-White participants are severely underrepresented in clinical trials for Parkinson's disease treatments.

## Contribution

The paper provides the first systematic review and meta-analysis on racial/ethnic diversity in PD disease-modifying drug trials.

## Key findings

- Only 1.4% of participants in trials were Asian, 0.19% Black, and 0.17% Hispanic.
- 98% of participants in the trials were White, showing significant underrepresentation of minorities.
- Most studies (51.4%) reported race/ethnicity data, highlighting a gap in demographic transparency.

## Abstract

There is a historic underrepresentation of non-White participants in Parkinson’s Disease (PD) research, although this has not been explored in trials for potential disease-modifying therapies.

To evaluate the representation of racial/ethnic minority patients enrolled in double-blind, randomized, placebo-controlled clinical trials (DBRCTs) for PD.

A systematic search of four electronic databases was performed. DBRCTs evaluating pharmacological therapies for disease modification in PD were included. Data extraction followed PRISMA guidelines. We computed demographic data with pooled prevalence and 95% confidence intervals (CIs).

Among 37 DBRCTs and 11,022 patients, 19 studies (51.4%) reported race/ethnicity, being 1.4% Asian, 0.19% Black, and 0.17% Hispanic. Pooled prevalence of participants identified as White in clinical trials was 98% (CI 0.97–0.99, P < 0.001).

Racial and ethnic minorities were disproportionately underrepresented in DBRCTs for potential disease-modifying therapies for PD. Additional efforts are required to increase the racial and ethnic representation in such studies.