Recruiting and retaining participants in early-phase trials

Recruiting and retaining participants in early-phase trials

by Stephanie Wells, Corporate Senior Vice President and Chief Marketing Officer, Charles River 

The early-phase clinical trials stage is an exciting but stressful milestone for a compound headed toward market release. Significant effort, resources, and planning have brought the product to this point; where its benefits, properties, and potential problems will be tested in real-life circumstances will determine whether the product does indeed continue onward toward market release.  

Because so much is at stake, it is vital that clinical trials given the best opportunity to succeed. This includes rapid start-up times, prompt reporting, and the ability to ensure patient safety and retention. For this goal to be reached and an efficient and effective clinical trial carried out, it takes an exacting approach to recruitment, in-depth knowledge of participant populations, and proven retention methodology. Such implementation requires forethought, planning and ongoing commitment from the clinical research organization running the trial. 

Participant Recruitment

Participant recruitment is one of the first steps of any clinical trial program, and a big component of successful recruiting may need to involve a grassroots-type marketing approach to attract local residents.  

The standard local marketing techniques work as a jumping-off point, including fliers in high-traffic areas, referral bonus programs, event sponsorships, and local media advertising. But too often CROs view this as a be-all end-all approach instead of utilizing more certain methodologies that can be employed to better use resources, measure returns, and ensure that sponsors receives the best cohort for their investment.  

The Community

The stereotype that the clinical trial environment is a sterile, cold "laboratory" hinders participant recruiting. To counteract this, the key to successful participant recruitment is to develop and foster long-standing, strategic relationships with the community in such a way that it puts a human face to the research. This goal is accomplished through active involvement in community events, including sponsorship of charity activities, booth presences at local festivals and community fairs, and regular college campus outreach.

Using a website to strategically communicate recruiting priorities is an easily maintained resource that allows potential participants convenient access to up-to-date, accurate information. However, with today's social environment becoming more centered around the Internet, a website is only the minimum level of technology involvement that should be incorporated into a recruiting strategy. Keeping track of and utilizing emerging social and software applications allows a CRO to stay connected with the participant. This includes offering participants the option to register and make appointments online, which goes a long way in ensuring that participants are registering and making appointments at all. 

The Media

An ongoing, strategic relationship with local media is just as important as a relationship with the community. CROs need to constantly seek out new venues, stay current in the market place to avoid saturation, and work with vendors to develop and place advertisements that secure optimal response levels.  

When developing an advertising program, it is important to monitor responses while ensuring enough flexibility to be able to alter plans promptly. Responses can be tracked daily through a recruiting database, and that information can then be discussed with vendors to determine the next course of action. If a response is not favorable, CROs with solid vendor relationships can often cancel an unsuccessful media buy or request additional free spots to ensure the money is well spent. Maintaining close contact with vendors also ensures that an advertisement is well-timed and is attracting the attention of the appropriate demographic group.

For a smaller CRO trying to develop an advertising strategy, it may be necessary to combine study budgets and run standard generic ads, but for more advanced CROs, strategic advertisement creation yields better results. Advertisements should be study-specific and differentiated to invoke interest, prevent redundancy, and attract the relevant intended study populations.  

When appropriate, include the stipend in the advertisement. Responses are significantly lower without compensation information, and as a rule of thumb, sponsors will need to double their advertising budget to make up for the lower response rate that will occur if the stipend information is omitted.  

These types of direct involvement with the local community and media often lead to networking opportunities outside the community as well. Through authentic interaction with vendors and community partners, a CRO can access other participant populations in neighboring communities.   

Participant Populations

Participant recruitment is more than just a matter of being able to offer the appropriate number of participants in an efficient amount of time. According to a recent Tufts Center for the Study of Drug Development report1, sponsors are increasingly looking for targeted patient populations, although only a small percentage of Phase I CROs have therapeutic specialties. As a result, participant recruitment is also a matter of having an understanding and mechanism for accessing particular participant populations, knowing sponsor needs in advance, and having insight into shifting industry trends. 

For instance, first-in-human (FIH) studies are frequently being designed to include female participants, which introduces a new level of complexity to recruitment, retention, and monitoring methodology. In addition, healthy older adults are being requested to address safety and pharmacokinetic characteristics, which involves another, different level of complexity. Vaccine trials also require a special population compared to standard Phase I trials, as well as longer follow-up periods.  

Although the basic processes of recruiting do not change, specific patient recruiting is still quite different from the recruitment of normal, healthy participants. Calls are longer, medications and medical history are discussed in more detail; restrictions like concomitant medication limitations are designed differently; and cohort sizes tend to be smaller and more intimate with a focus on the individual. As a result, such studies require a more experienced recruiter with in-depth knowledge of specific therapeutic areas and patient populations. 

CROs must focus resources in advance to accommodate these special sponsor requests. These resources include: hiring dedicated patient recruiters; designing advertising plans that target specific patient populations; and utilizing relevant vendors for advertising and community events, including medical condition-specific periodicals, support groups, and charity events. 

Participant Retention

Once a study is fully enrolled with the right participants, the priority then shifts to one of retention, or keeping the participant in the study for the duration of its term. This goal can be particularly challenging in long-term studies, but is helped by quality recruiting practices ensure that the right type of participants are enrolled. 

The best approach to ensuring customer retention is to establish multiple groups of personnel who are dedicated to the needs, comforts, and experiences of the participants, as well as to their continued recruitment.  

For instance, a participant advocate resource can be created to keep participants comfortable and entertained. This includes providing Internet and phone access and organizing activities such as movies, games, exercise and seasonal activities--all while ensuring adherence to study restrictions.  

Effective participant advocates support in-house participants, discussing their comfort, needs, and suggestions, and providing ideas to management that facilitate change based on participant feedback. Advocates also serve as key contacts participants who may be intimidated by doctors and nurses. As a result, participants are more open about personal circumstances that could affect the study data (e.g., side effects) or their retention (e.g., unhappy with a roommate). This openness ultimately ensures a more effective trial. 

Another important group to establish is an inactivation committee. This committee, composed of representatives from departments that interact with participants, should be tasked with ensuring participant compliance with house rules, protocol requirements, and overall patient safety. The committee can review reports on participants to determine if they are appropriate candidates for future studies, limited to a short-stay study, or subject to some other restriction.  

In addition, dedicated study teams are needed to maintain relationships with study participants throughout the duration of the trial recruiters should be also be utilized to speak with alternates as they discharge, providing opportunities to enroll a participant in future studies.  

Along with these various roles, routine reminder calls should be conducted to ensure participants return for outpatient visits or scheduled inpatient stays, and emails and letters should be sent to individuals in the database who have not enrolled in a study for a long period of time. In addition, fliers with details about future studies should be inserted into all participant stipend checks.


Participant recruitment and retention for early-phase clinical trials takes more than just casting as large a net as possible and hoping for great results.  It takes focus, commitment, expertise, exacting methodology, and flexible processes and resources. Sponsors should assess the capabilities of CROs to address these needs to maximize the effectiveness of trials, regardless of the participant, patient population or study duration. 


1. Project on the Phase I Market Structure, Needs and Practices, Tufts Center for the Study of Drug Development, January 2008.