Strategies for Increasing Racial and Ethnic Diversity in Hemophilia Clinical Trials and Their Outcomes

Introduction

Hemophilia, an X-linked genetic disorder, causes deficiency of blood-clotting proteins and primarily affects men (D'Angiolella LS, et al. Eur J Haematol. 2018). Compared to that in White patients, Black/African American (AA) patients have higher incidence of inhibitor development, higher bleeding complications and higher risk of intracranial haemorrhages. In addition, Black and Hispanic people with hemophilia remain underrepresented in clinical trials (Fedewa SA, et al. Haemophilia. 2023). To maximise study validity and generalisability, it is imperative to improve diverse representation in study populations. Here, we evaluated the impact of operational strategies implemented to increase racial and ethnic diversity among the participants of Hemophilia trials (NCT03974113, NCT04759131, and NCT05662319).

Methods

Hemophilia clinical trials conducted from January 2020 to July 2024 were included. Diversity and inclusion (D&I) goals were established based on the US epidemiological data sourced from TriNetX, primary literature, and US Census data. D&I goals are representative of real-world disease prevalence data in the United States. The progress of enrollment goals was tracked using the Diversity & Inclusion Metrics Overview (DIMO), a proprietary and sophisticated real-time clinical trial enrollment tracking software. Industry best practices were implemented to develop operational strategies aimed at enhancing patient understanding and increasing site capacity for underserved populations.

To achieve the D&I goals, operational strategies were implemented throughout the development program. First, the sites were selected based on pre-existing data, and the sites with access to diverse patient populations were prioritized. Second, patient and site-support measures were included. The recruited sites received assistance in pre-identifying participants, and transportation expenses of the participants were reimbursed. To ensure all participants had access to recruitment and retention materials, the materials were translated into additional languages, including eDiaries, mechanism of action videos, and an activity book. The continuous site engagement model incorporated D&I considerations during each site visit and diversity goals were discussed from the trial’s initiation throughout recruitment. This wholistic approach was integral to achieving D&I goals.

Results

Diversity enrollment targets were achieved in each of the minority groups assessed. In the studies examined, enrollment of Black/AA participants was 31.1% (target 13%); for Asian participants, the enrollment rate was 13.1% (target 5%) and for Hispanic or Latino participants, the enrollment rate was 24.6% (target 13%).

Conclusion

Enrollment data highlight effective operational strategies and further emphasize the value of an end-to-end, technology-enabled approach to recruitment of diverse patient populations. The inclusion of diverse populations in Hemophilia clinical trials could provide important clinical data, potentially improving treatment outcomes and access for underserved populations.