OBJECTIVES: The US Food and Drug Administration published draft guidance in 2022 to improve diversity in clinical trials. The UK’s Medicines and Healthcare products Regulatory Agency is currently developing similar guidance. Researchers have proposed methods for setting diversity enrolment goals in trials (Cullen et al, 2023) using real-world data (RWD). This analysis examines enrolment goals for two types of cancer (liver cancer and melanoma) as hypothetical examples, for England and the US, to explore potential challenges for sponsors of global trials seeking to meet country-specific diversity requirements.

METHODS: Cancer incidence by race and ethnicity was obtained from Public Health England (PHE) for England and from the Surveillance, Epidemiology, and End Results program of the National Cancer Institute for the US. Using census data and methods proposed by Cullen et al, we calculated enrolment goals for race/ethnic groups in England and the US.

RESULTS: Target enrolment goals differed considerably between England and the US. The greatest difference was observed in Black patients (liver cancer: England: 4.2%, US: 13.7%; melanoma: England: 4.2%, US: 12.7%). There were also large differences in enrolment goals for White patients (liver cancer: England: ≤81.0%, US: ≤55.2%; melanoma: England: ≤81.0%, US: ≤58.3%) between countries, driven by a 19.4% enrolment goal for US Hispanic patients, whereas there is no Hispanic category in England’s census or PHE data.

CONCLUSIONS: A key challenge in setting country-specific diversity goals is identifying suitable RWD sources that reflect the indicated population. This is compounded if requirements for multiple countries with different demographics and disparate data sources need to be met. Setting multiple country-specific goals may increase the complexity of trial planning, as relying on combined targets globally may fail to meet a specific country’s requirements. International cooperation and coordinated guidance may be needed to assist sponsors of global trials in meeting diversity requirements.