Lack of Racial Diversity in Blanching Clinical Trials Hindering Medical Advancements

Image Credit: Dave Randolph in the San Francisco Chronicle

Neha Natu investigates the implications of disparities in American clinical trials.

Clinical trials are research studies that involve human participants to test new drugs, therapies, or medical procedures. Although over 40% of Americans belong to racial or ethnic minorities, patients who engage in clinical trials for new pharmaceuticals are mostly white—in some cases, 80 to 90%. However, non-White patients will eventually take the treatments that come out of clinical trials, which creates a genuine dilemma. Black patients account for just 5% of clinical trial participants in the United States, while White patients make up the vast majority. Clinical trials often do not have adequate representation of diverse racial and ethnic groups: if a trial has a predominantly non-diverse participant pool, it may not capture the range of genetic and biological factors that could affect drug response in other populations. Racial and ethnic participation in global clinical trials is an important aspect of medical research, as it helps ensure that healthcare interventions and medications are safe and effective for diverse populations. It is thus essential that these trials include a representative sample of the population to understand how these interventions may affect various racial and ethnic groups differently.

Clinical drug trials that appear to work differently or less effectively in specific racial or ethnic groups are a topic of concern in healthcare, as they can raise questions about potential health disparities and unequal treatment. It's essential to understand that the reasons behind these disparities are complex and may not solely be due to the individual's race or ethnicity. Instead, they can be influenced by a range of factors, including genetic variations, socioeconomic factors, and healthcare access.

Clinical trials should aim to include a diverse range of participants representing different races, ethnicities, and backgrounds. This diversity is crucial because individuals from different racial and ethnic groups can have variations in genetics, biology, and responses to treatments. This is the study of pharmacogenetics. These genetic differences can influence how drugs are metabolised, how they interact with the body, and how effective or safe they are for different individuals. Certain racial and ethnic groups may have a higher risk of experiencing specific adverse effects due to genetic predispositions. For example, some individuals may be more susceptible to skin rashes or liver toxicity from particular medications. Only 2% of cancer research and fewer than 5% of pulmonary studies have investigated minorities sufficiently to offer valuable information. Clopidogrel, or Plavix, is a blood thinner that is ineffective in the 75 percent of Pacific Islanders whose systems do not manufacture the enzyme essential to activate the medicine; taking the drug is like taking a placebo for them. People of Asian heritage with epilepsy are required to undergo genetic testing before being administered the seizure medicine carbamazepine, because the treatment can harm the skin and internal organs of patients with a certain gene mutation. African-Americans and Puerto Ricans do not respond as well to some of the most commonly used asthma controller drugs, which is a shame because these two populations are the most impacted by asthma in the United States. It's important to note that the relationship between genetics and drug response is complex, and genetic variations are just one of many factors influencing drug effectiveness and safety. Factors such as age, sex, underlying medical conditions, and environmental factors also play a role in an individual's response to medications. A less diverse clinical trial can be harmful for several reasons, as it can have far-reaching implications for the safety, efficacy, and applicability of medical treatments and interventions.

Only 2% of cancer research and fewer than 5% of pulmonary studies have investigated minorities sufficiently to offer valuable information. 

Historically, racial and ethnic minorities, especially in the United States, have been underrepresented in clinical trials due to systemic barriers, mistrust, socioeconomic factors, and access to healthcare. The Tuskegee Syphilis Study is one of the most infamous and ethically egregious examples of an unethical clinical trial involving Black people. This study, which lasted for 40 years between 1932 and 1972, was conducted by the U.S. Public Health Service and involved the mistreatment and exploitation of African American men in Macon County, Alabama. The study aimed to investigate the natural progression of syphilis, a sexually transmitted disease, in African American men. Researchers enrolled 600 participants, most of whom had syphilis, and some who did not (control group). Participants were not informed about the nature of the study, its risks, or the fact that they were participating in a clinical trial; they were misled into believing that they were receiving treatment for ‘bad blood’. Even when effective treatments for syphilis, such as penicillin, became available in the 1940s, researchers deliberately withheld treatment from the participants, allowing their health to deteriorate and causing severe harm. The study violated fundamental ethical principles, including the requirement for informed consent, respect for the autonomy of participants, and the duty to provide proper medical care. 

Another tragic example is Henrietta Lacks, a poor African American woman, who did not provide informed consent for the use of her cells in medical research. The biopsy of her cervical tissue was taken without her knowledge or permission. The use of her cells without her consent or knowledge exemplified a broader pattern of medical exploitation and disregard for the rights and dignity of African American patients during that era. Henrietta Lacks's story is deeply intertwined with issues of racism and systemic injustices in healthcare and medical research. Her legacy serves as a reminder of the importance of addressing healthcare disparities, systemic racism, and the ethical considerations surrounding medical research involving marginalised communities. It also underscores the need for equitable access to healthcare and respect for patients' rights, regardless of their racial or ethnic background.

When minority groups consistently see themselves excluded from clinical trials or other healthcare initiatives, it can further erode trust in the medical and research communities. This mistrust can lead to reluctance to participate in research or seek healthcare services, which has negative public health implications. Building trust within underserved communities is crucial to encourage participation in clinical trials. Community engagement, education, and partnership with local healthcare providers and organisations can help foster trust and encourage participation. Transparency in reporting the demographic data of clinical trial participants is vital, and this information should be publicly accessible to ensure accountability and to monitor progress in achieving diversity and inclusivity goals. Promoting racial and ethnic diversity in clinical trials is a step towards addressing health disparities, as it helps ensure that healthcare interventions are developed with a focus on reducing health inequities.

When clinical trials lack diversity and under-represent certain racial or ethnic groups, it may result in treatments that are less effective or entirely ineffective for those populations. As a result, patients from underrepresented groups may receive treatments that do not work optimally, leading to poor health outcomes and the need for alternative treatments. Underrepresentation in clinical trials can exacerbate health disparities, as treatments may not be optimised for the specific needs of underrepresented groups. Health disparities and the inefficient use of healthcare resources can lead to higher societal and economic costs. This includes lost productivity, increased hospitalizations, and greater healthcare spending.

Underrepresentation in clinical trials can exacerbate health disparities, as treatments may not be optimised for the specific needs of underrepresented groups. Health disparities and the inefficient use of healthcare resources can lead to higher societal and economic costs. 

As the U.S. becomes more diverse, it is essential to fill these gaps — and could help make a dent in the estimated $300 billion lost each year because of health disparities. Addressing these disparities is essential to ensure that medical advancements benefit everyone. Efforts to ensure that drug trials are inclusive and representative of diverse populations are ongoing, and regulatory agencies like the U.S. Food and Drug Administration (FDA) have guidelines and initiatives to promote diversity and inclusion in clinical research. These efforts aim to ensure that medical treatments are safe and effective for everyone, regardless of their racial or ethnic background.

It is essential to recognize that addressing disparities in drug effectiveness requires a multi-faceted approach that includes increasing diversity in clinical trials, improving healthcare access and equity, and advancing pharmacogenomic research. Pharmacogenomics, which considers an individual's genetic makeup in drug therapy, is an evolving field that holds promise for tailoring treatments to the specific needs of patients, irrespective of their racial or ethnic background. In some cases, tailored or precision medicine approaches are developed to account for these differences and provide more effective treatments. Pharmacogenetic research and personalised medicine are rapidly evolving fields that hold the promise of more effective and safer drug treatments tailored to individual genetic profiles, helping to improve healthcare outcomes and reduce the risks associated with medications.