There is a disproportionate representation of diverse racial and ethnic groups when compared to the over-representation of white counterparts in clinical trials. Since race and ethnicity are known to contribute to interindividual differences in drug exposure along with responses, the risk-benefit ratio is thus altered in certain populations.
At the 14th American Association for Cancer Research (AACR) Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved, held virtually on 6–8 October, the results of a simulated pancreatic cancer clinical trial screening process revealed that Black patients were significantly more likely to be excluded from pancreatic clinical trials than their white counterparts. The criteria most likely to lead to the exclusion of Black patients included level of albumin (for which the trial excluded 14.07% of Black patients versus 7.91% of white patients) and hepatitis C (for which the trial excluded 9.06% of Black patients versus 3.43% of white patients) among others.
While compliance in patients with underlying infectious disease is a noteworthy issue, it does not warrant the exclusion of these subgroups, as they may reflect the patient populations that are likely to use the drug in clinical practice. As such, careful consideration must be taken to broaden cancer trial eligibility criteria to avoid jeopardising patient safety. The simulated pancreatic study further highlights the pressing issue of templating historic eligibility criteria across trials without a clear scientific or clinical rationale.
This racial disparity exists beyond oncology and extends into many areas of healthcare management. One such area is the field of cardiovascular disease, where it has been generally reported that heart conditions disproportionately affect Black patients due to a higher prevalence of risk factors in that group, such as high blood pressure, obesity and diabetes. According to the 2018 national vital statistics report, African Americans were 30% more likely to die from heart disease than non-Hispanic whites. Despite this, the US Food and Drug Administration’s (FDA) Global Participation in Clinical Trials report found that African Americans only accounted for 2.5% of cardiology clinical trial participants.
Covid-19 is the most recent area to face ever-growing concerns of the ethnic disparity in clinical research among the Black, Asian and Minority Ethnic (BAME) community. Last year, the Intensive Care National Audit and Research Centre revealed that 34% of Covid-19 related admissions in England and Wales were from the BAME community, despite the fact that they only accounted for 13% of the population in those areas. GlobalData epidemiologists reported that Black patients had the highest death rate due to Covid-19, with 62 deaths for every 100,000 of the Black population reported in the US, and 41 deaths for every 100,000 of the Black population reported in the UK.
Both the US and UK also reported that those of white ethnicity had the lowest death rate due to Covid-19, with 26 deaths for every 100,000 of the white population reported in the US and 22 deaths for every 100,000 of the white population reported in the UK. Despite this data, the BAME community was still inadequately represented in the clinical trials for the development of Covid-19 vaccines. The National Institute for Health Research (NIHR) analysed the ethnicity data provided by a total of 622,978 participants taking part in studies across the UK and found that only 5.8% of the vaccine study participants were from an ethnic minority.
To reverse this underrepresentation and increase diversity within clinical trials, awareness and patient population-targeted recruitment must be at the forefront. In addition, research organisations need to rebuild trust and dismantle negative preconceived notions of safety in clinical trials that exist within the BAME community due to historical reasons. Diversifying clinical trials ensures that healthcare delivery and public health strategies are appropriately tailored to all populations, will maximise the generalisability of trial results and will increase clinical knowledge of the disease pathophysiology and range of genetic profiling.