Homogeneous trials present a missed opportunity to discover treatments that might be highly successful in a particular subset of patients.
For decades, there has been a persistent lack of diversity among cancer-related clinical trial participants. This disparity affects both the patients and the science. A community-based approach to cancer care and research could offer a solution.
Though homogeneity is not unique to cancer trials, it is especially troubling to see it in the context of patients with cancer because clinical trials offer a means to access the newest and most promising treatments, such as immunotherapy.1 Further, profiles of disease are diverse and vary across gender,2 race/ethnicity,3 and other patient characteristics. Homogeneous trials present a missed opportunity to discover treatments that might be highly successful in a particular subset of patients.
In an analysis of phase 3 cancer-related clinical trials conducted between 2001 and 2010, results showed that 83% of participants were White, 6% were Black, 3% were Asian, 2% were Hispanic, and less than 1% were Native American.4 These results skewed heavily White compared with the overall racial demographics of cancer incidence in the United States.5
Despite efforts to increase diversity in clinical trials, such as the National Institutes of Health (NIH) Revitalization Act of 1993,6 which required the inclusion of more women and individuals of color in trials funded by the NIH, diversity of among participants enrolled in oncology trials decreased in the 2000s, compared with the previous decade.7
That is troubling because we know from other fields of study that the efficacy of certain drugs for patients in one racial or ethnic group do not necessarily generalize to others,8 or they may have unforeseen adverse effects among minority groups that were not adequately represented during the testing phase.9 Currently, Black patients with cancer have a 28% higher mortality rate compared with White patients,10 and if the standard of care continues to be defined using predominantly White volunteers this inequity in cancer outcomes will persist.
One reason for the lack of racial and ethnic diversity in oncology trials is the not-so-distant memory of abuse medical establishments inflicted on minority communities, which has led to well-founded mistrust. But it is important to remember that hesitancy is not the same as refusal, and the onus is on clinical investigators to invite participation and address fears up front.
Elderly patients11 or those who live in rural12 regions are also historically underrepresented in oncology trials, which tend to be run through academic medical centers. In many cases these institutions are located hundreds of miles from patients’ homes,13 and there’s evidence that this lack of access to clinical trials has an effect on patient outcomes. Data show that patients with cancer in rural communities tend to fare worse than their urban counterparts,12 but when trial participation was controlled for, the mortality gap between rural and urban patients vanished.14
Another part of the issue underlying clinical trial homogeneity is that enrollment in clinical trials is generally low. Despite the fact that oncology trials provide the opportunity to access the most advanced treatments not yet available in the clinic, less than 5% of patients with cancer in the US enroll in a clinical trial.15 Instead, the vast majority are treated in community clinics.
Designing trials that meet patients where they are could not only improve overall enrollment but also trial diversity, allowing for therapies to be tested on a population that is more representative of the patients we treat in our day-to-day practice. Otherwise, how are we to know that a treatment regimen tested mostly on young, White, urban individuals will work for patients who fit none of those characteristics?
This idea of bringing trials to the people is the heart of mission of the National Cancer Institute Community Oncology Research Program (NCORP)—a network of 46 community sites across the US, 14 of which are designated as minority/underserved sites that aim to make trials more inclusive to historically underrepresented groups (Figure).
Figure. Map of NCORP Community and Minority/Underserved Sites
Virginia Commonwealth University (VCU) Massey Cancer Center in Richmond is a Minority/Underserved NCORP (MU-NCORP) site and, as a principal investigator for the VCU MU-NCORP grant, I have seen firsthand how powerful this program can be when it comes to bringing high quality cancer care to individuals who need it most.
On average, approximately 30% of our clinical trial participants belong to racial and ethnic minority groups, which is much higher than the national average of 17%, thanks in no small part to the MU-NCORP program, which gets us out in the community—and not just when we are trying to recruit.
Since it is critically important to build a foundation of trust, first we cultivate a presence and open a dialogue in the community. We offer screening, prevention, and education programs, then, when the opportunity to participate in a trial arises, we are there to answer questions, dispel myths, and address fears.
For instance, many patients with cancer have the misconception that if they sign up for a trial, they may be given a placebo or they worry that the drug is experimental and untested. We tell patients that they will at worst receive the current standard of care and that most NCORP trials are phase 3, so the drugs have already been through rigorous phase 1 and 2 safety and efficacy testing in smaller groups before being deployed in large-scale community trials.
We also use social media platforms, such as Facebook Live, and attend health fairs and screening events to talk with individuals in the community about health. Through these events we also start conversations about obesity, smoking, and overall wellness—the foundations of cancer risk reduction.
Sadly, the COVID-19 pandemic put a damper on these efforts. Although Zoom may be accessible to some, it is less so for others, and we have had fewer participants overall. Losing these events in addition to a drop in in-person screening opportunities around the country may have contributed to cancer detection rates decreasing since March 2020.16 As we emerge from the pandemic, it will be critically important to get community cancer initiatives back on track.