In July 2024, the U.S. Food and Drug Administration (FDA) published a draft guidance to ensure greater diversity in clinical trials, which is expected to become a final guidance by June 2025. For many drug developers, this guidance has been long-awaited, as it emphasizes inclusivity of underrepresented and minority populations not only in late-stage clinical trials but throughout the entire clinical process, including early stages

Regulatory organizations like Health Canada, the International Council for Harmonisation (ICH), and the European Medicines Agency (EMA) have long emphasized the importance of including diverse populations in clinical research. The EMA's ACT EU (Accelerating Clinical Trials in the EU) initiative specifically advocates for diverse participant inclusion to produce robust clinical data and improve healthcare outcomes.

Similarly, Health Canada's guidance highlights the need to represent various demographic groups in clinical trials, ensuring that study results are broadly applicable for enhanced safety and efficacy of drug development.

Effective strategies to build representation into study designs are essential, and diversity in clinical participation provides more comprehensive insights into how treatments work across diverse demographics. 

Why Diversity in Clinical Trials Matters

A wide variety of factors, from age or biological sex to environmental conditions and lifestyle choices (e.g., substance abuse, sexual activity), can influence the risk and likelihood of developing a disease or other long-term health issues—as well as the way an individual responds to treatment. For example, elderly individuals are more prone to comorbidities, dementia, and functional decline. Additionally, age-related physiological changes can alter the pharmacokinetics and pharmacodynamics of drugs, often reducing the body's ability to metabolize or eliminate certain medications, which may result in prolonged presence in the system.

Furthermore, there are cases in which certain racial groups biologically react to particular conditions or treatments. Pancreatic cancer, for example, does not affect all populations equally and, between 2000 and 2020, African Americans in the United States persistently had a 19% higher incidence of pancreatic cancer when compared with other racial groups. Similarly, more than 90% of people in the United States with sickle cell disease are Black, with an estimated three to nine percent being Hispanic or Latino.

Genetic variations observed in different racial groups' genomic profiles can also be a contributor to adverse therapeutic responses to drugs. Up to 75% of Pacific Islanders, for instance, cannot metabolize the antiplatelet drug clopidogrel into its active form, increasing their risk of adverse outcomes after angioplasty.

These are just some examples that highlight the critical importance of diversity in clinical trial data for the medicines reaching the market. Ensuring the representative participation of various populations helps capture the genetic and biological diversity that affects drug metabolism and therapeutic responses.

Ways to Increase Diversity in Clinical Trials

One of the most important ways to increase inclusivity in clinical trials is to start with the study team itself. With unbiased hiring practices, researchers can assure participants that they will not face differential treatment based on their race, sex or gender, sexuality, or age. Dr. David Nguyen, General Manager and Medical Director of Altasciences’ Los Angeles clinical pharmacology unit, says:

“Having a diverse medical team working with a diverse participant population can lead to a rewarding experience for both. Participants can relate and express cultural concerns to those charged with overseeing their well-being, and participants often establish lasting friendships with others outside their usual social circle when in a clinical trial. Through it all, the sponsor benefits from the robust data reflective of the different genotypes in their study.”

Building trust is another big factor in recruiting and retaining a diverse pool of study participants. Medical institutions have historically cultivated mistrust among minority groups, by traditionally recruiting primarily Caucasian men, and through a history of research abuses (such as the U.S. Public Health Service Syphilis Study at Tuskegee, conducted between 1932 and 1972), as well as restrictions on equitable access to clinical services that continue to the present day. 
 


A 2022 study found that sharing results from a hypertension drug trial with 15% Black participants increased Black patients' confidence in the drug's effectiveness by 20%, while perceptions among white patients remained unchanged, demonstrating the importance of representative participation in boosting trust and treatment acceptance across diverse populations.

We at Altasciences work to ensure that all ethnic populations are not only represented, but also have the necessary cultural, language, and dietary considerations incorporated into their clinical programs—which fosters a more comfortable and sensitive environment and helps to ensure informed consent. 

Outreach programs within local communities can also be an effective and rewarding way to create a trusting mutual relationship with the communities of the desired populations, bolstering recruitment efforts. Altasciences participates in local Asian film festivals and local summer festivals with pop-up stalls to build bonds with the surrounding Asian communities, which in turn has seen a rise in clinical trial participation within this population. 

Increasing diversity in clinical trials can also be approached by conducting trials within communities being studied, or by mitigating logistical and location-related challenges, a common barrier to clinical trial participation. Approximately 70% of potential participants reside over two hours away from a study center, leading to substantial travel time and significant life disruption when frequent site visits are necessary. As such, it can be beneficial to offer travel options for out-of-state or international site visits. This minimizes the variability in data when a study goes hybrid and improves compliance and quality of data.

In Conclusion

By partnering with organizations such as Altasciences that are experienced in, and are proactively engaging diverse communities, meaningful strides can continue to be made towards inclusivity, ensuring that clinical trial results not only reflect the broader population more accurately but also build confidence in study participants.

The new FDA draft guidance represents a significant step towards enhancing inclusivity in clinical trials, but there is still much work to be done.