Guest Column | October 30, 2023

3 Reasons People Don't Enroll In Clinical Trials — And How To Overcome Them

By Adrelia Allen, executive director, clinical trial patient diversity, Merck


When my father was diagnosed with prostate cancer, I was confronted with the long-lasting impact of medical mistrust — particularly within the African American community. At the time, he refused to get an MRI because mistrust of the medical industry was a very real issue for him, which was amplified by his concern of being treated like a “guinea pig.”

It’s difficult to change someone’s mind when they’ve seen and experienced things that make them fearful of how they will be treated based on the color of their skin. And while my background in medicine enabled me to help address his concerns about his condition and options, many people don’t have access to this type of support.

The importance of equity in clinical trials — meaning that participants represent the people who are most likely to have the health condition and greatest need for the treatment that the trial is evaluating — cannot be overstated. People of different ages, genders, sexes, ethnicities, and races can respond differently to medicines, and without diverse representation in clinical trials, we aren’t able to study whether treatments will work for everyone who needs them.

While diversity in clinical trials recently became a national policy priority in the U.S., participants are still overwhelmingly white: In 2020, 75% of trial participants were white, 11% were Hispanic, 8% were Black, and 6% were Asian. In prostate cancer, for example, outcomes are worse for Black men because they are less likely to be screened or to receive treatment. They are also unlikely to participate in clinical research, which makes it difficult for investigators to understand how they are impacted by the condition.

To help ensure that medical research is inclusive, the healthcare community must continue to invest in new ways to educate, recruit, and engage clinical trial participants who are demographically diverse. So, what are the issues that are preventing people from enrolling in clinical trials, and which strategies and tools can we utilize to help overcome them?

  1. Distrust in the healthcare system: Many individuals from historically marginalized communities don’t trust healthcare systems, and for good reason. For generations, medical mistreatment has plagued our healthcare and clinical trial systems, from the Tuskegee syphilis study to striking disparities in pain treatment that persist today.4

Knowing that trust is at the root of someone’s decision to participate in a clinical trial, action needs to be taken to build relationships within communities in which clinical trial participation is low. One step toward accomplishing this is increasing the diversity of research coordinators and investigators. Research has demonstrated that having a medical provider who shares the same lived experience or understands a person’s culture is key to building trust.5

One way we aim to tackle this at Merck is through our collaboration with Beacon of Hope — an initiative created by Novartis and the Novartis U.S. Foundation. As part of this program, we are working toward operating clinical trials through four historically Black medical schools. These trials will be conducted by investigators and managers of color with participants from underrepresented populations.

We’ve also found that utilizing digital channels that serve as a source of information specifically for Black Americans — like the Clinical Trials Resource Center of (BDO) — helps us connect with patients who are seeking trustworthy sources of information. Our hope is that these efforts, combined with enhanced provider and researcher training to help ensure that all care is grounded in cultural humility, will improve trust, trial participation, and, ultimately, health outcomes.

  1. Low clinical trial awareness levels: Many people do not enroll in clinical trials simply because they don’t have enough information about them or how to participate.

The digital platforms at our fingertips today can be powerful tools for creating widespread awareness of clinical trial opportunities. Organizations should seek ways to compliantly share information about clinical trials across platforms where potential participants are already spending time and engaging. It’s important that this information is accessible and culturally appropriate. For instance, we are sharing information online about Merck clinical trials via our collaboration with BDO to help improve Black Americans’ participation in clinical trials.

While technology is a valuable tool in clinical trial recruitment efforts, we can’t underestimate the importance of connecting and having conversations with patients face to face. In 2021, when COVID-19 was disproportionately impacting racial and ethnic minority communities in the U.S.,6 we deployed a mobile clinical research unit in underserved Latinx communities in Florida to support Merck’s antiviral research. During this deployment, over 10,000 people approached the mobile unit for information and more than 5,200 conversations were held about clinical trials. More than 8,000 informational brochures were distributed to those interested in learning more about clinical research, which demonstrates that the public is eager for information. The unit is currently deployed in Southern California as we work with one of our diversity-focused sites, and it has been utilized at health fairs and community events to foster community engagement, increase clinical trial awareness and education, and to share specific volunteer opportunities.

  1. Financial and travel barriers: Before participating in a clinical trial, many have concerns about the time commitment and the potential expenses directly and indirectly associated with participation, including childcare and travel expenses.

Unsurprisingly, research has shown that the top two enhancements to increase patient participation in clinical trials are expense reimbursement and transportation assistance.7 Technology can help us accomplish this by enabling clinical data to be collected remotely, reducing the number of visits required at a physical trial site. And when travel is needed, rideshare platforms can help make a difference. In Merck’s agreement with Greenphire, participants across our clinical development network can request rides and receive reimbursement related to trial-related travel.7

Merck is committed to ensuring that our research reflects the people we serve. While there is still work to be done, I believe that by collaboratively addressing the challenges we’re facing today alongside our peers, we can help create a future where our research includes participation of people from all backgrounds.


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About the Author:

AdreliaAdrelia Allen, Pharm.D., is a 22-year veteran of the pharmaceutical industry working in sales and clinical research at Merck. She has held positions of increasing experience as a clinical research associate, clinical trial project manager and clinical research manager (CRM). She is currently the executive director of clinical trial patient diversity and is responsible for the strategy and execution of activities for the diverse representation of patients in clinical trials. Allen has a Doctor of Pharmacy degree from Florida A&M University College of Pharmacy.