Starting with a small fleet of buses retrofitted to provide mobile COVID-19 testing and vaccination in underserved communities, one Maryland site has leveraged this access to boost recruitment and diversity in its trials.

In early 2020, Centennial Medical Group in Elkridge, Md., provided an urgent care site that was one of the few places in the area offering COVID testing. The facility was quickly overwhelmed with residents seeking testing, with as many as 120 people waiting each morning at a site built to handle about 90 patients per day. Addition of a drive-in option helped with that workload, but Centennial wanted to do more to reach individuals who might not be able to drive to the site.

It opted to do so by going mobile, literally, Steven Geller, principal investigator and medical director for Centennial Medical Group, told CenterWatch Weekly. Working with county governments, Centennial was able to identify suitable locations that would be accessible to more patients. The bus provided COVID-19 testing, with results provided after a short wait, along with telehealth visits with a nurse practitioner or physician.

The shift to include research recruitment was natural when Centennial was selected as a site for some COVID vaccine trials. The sponsors wanted a large and diverse population of patients enrolled quickly. The buses providing testing services offered an ideal option for reaching patients already concerned about COVID, as well as expanding outreach to underserved populations, which helped increase diversity, Geller said.

As part of the intake questionnaire for COVID testing, patients were asked if they had interest in participating in a COVID vaccine trial; those that answered affirmatively were contacted later to discuss enrollment.

The outreach program also included incentives to make it easier for patients in less accessible communities to come to the sites for consenting and other necessary visits. For instance, the site would pay patients for travel time or provide an Uber ride to the site when needed, Geller explained.

“We ended up enrolling 655 people, the third-highest number in the country” for that trial, Geller said.

“As importantly, we also exceeded the sponsor’s diversity guidelines because the patients enrolled matched the communities.”

Centennial received the Society for Clinical Research Sites’ (SCRS) Site Patient Recruitment Innovation Achievement Award in 2021. The award, launched in 2014, aims to recognize sites that apply innovative strategies to improve enrollment.

The success of the program for COVID testing and vaccine trial recruitment led Centennial to expand from a single bus to five. And it expanded the services and types of trials recruited for as well. As the COVID-specific load wound down, Centennial expanded the use of its buses to more of a health equity initiative. While they still offer COVID testing, they also provide screening for a variety of health issues, including cholesterol, diabetes and STDs, along with telehealth visits.

“When we provide these services, we ask patients about any research study we are doing that is appropriate for them,” Geller said. “When we discuss their test results, we can also follow up with research questions.”

In addition to recent COVID vaccine research, Centennial has conducted studies on vaccines for pneumonia, influenza, respiratory syncytial virus and human papilloma virus. Other studies have involved treatments for obesity, diabetes and low testosterone.

Establishing a program like this is not without its challenges, Geller acknowledged. For instance, sites must be able to acquire a suitable vehicle and then outfit it for health outreach purposes. It costs about $20,000 to retrofit a single bus for the testing and telehealth services Centennial provides.

Operation of the vehicles can be another cost. Centennial’s buses cost about $1,000/day to operate; this includes the cost of a driver for the bus.

“The challenge is making sure it’s financially viable,” Geller said. “At the beginning, it was easy to justify because we were overwhelmingly busy. Home test kits for COVID lessened demand for that testing service.”

However, he noted that his site’s ability to successfully recruit a diverse patient population for clinical research helps bring in funding via additional clinical trials. It is important for sites to evaluate the volume of patients they can expect to get with a mobile program, the cost of implementing the program and the return on investment.

Sites must have the ability to staff a mobile service, as well. While Centennial maintains a full-time research staff of nine, it staffs its mobile service almost exclusively from clinical staff from its primary care and urgent care sites.

Determining which areas to target with a mobile recruitment program can also be challenging. Geller suggested that working with county and local governments can help sites figure out where to send their mobile centers, as well as where parking is allowed for the vehicles and patients arriving by car for testing.

Ultimately, he said, remote recruitment tied to routine health screening procedures is likely to be a useful part of a hybrid approach to clinical trials. Sites may even be able to perform some simple screenings or procedures as part of a clinical trial with vehicles like this, although they are likely to be less useful for obtaining consent or for more complicated study visits.