8 Patient Engagement and Retention Companies for Clinical Trials in 2026

A recruitment and retention provider works on the harder half of the enrollment problem: not just getting patients into a trial, but keeping them engaged, adherent, and completing the study once they've joined. This kind of patient retention service ranges from medication adherence software that tracks dosing behavior in real time, to nurse-staffed call centers that maintain a human relationship with participants throughout a study, to payment and mentorship platforms designed to remove the financial and emotional friction that causes patients to drop out.

The companies below are listed in no particular order. Between them, these companies and providers cover medication adherence monitoring hardware and software, participant payment and travel platforms, nurse-staffed patient engagement call centers, peer mentorship networks, and nonprofit clinical research education.

AARDEX Group

AARDEX Group builds MEMS AS, medication adherence software the company describes as the industry gold standard, using proprietary algorithms to detect erratic dosing patterns like missed doses and overdoses across every route of drug administration. Headquartered in Liège, Belgium with additional operations in Switzerland and the US, the company is led by CEO and Scientific Lead Bernard Vrijens, and its technology has been used in more than 200 clinical trials and cited in over 800 peer-reviewed papers. AARDEX has built an extensive partner ecosystem of connected adherence hardware, including agreements with etectRx for ingestible smart pill sensors, AdhereTech for smart pill bottles, and Pill Connect for connected dispensing devices, most recently supporting a multi-cohort Phase 2A dose selection trial in partnership with Pill Connect in August 2025. The company positions its accuracy as superior to older adherence measurement methods like pill counts and patient self-report, and its solutions are backed by FDA guidance on medication adherence packaging.

CISCRP

CISCRP (the Center for Information and Study on Clinical Research Participation) was founded in 2003 by Ken Getz, inspired by a 2002 TIME magazine cover story on clinical trial ethics, and operates as a first-of-its-kind 501(c)(3) nonprofit dedicated to educating the public about clinical research participation. The Boston-based organization runs AWARE for All events, interactive health education programs that reached 429,000 households between 2003 and 2013 alone, alongside a Communicating Trial Results program that translates study findings into lay-language summaries for the volunteers who took part in them. CISCRP has distributed nearly one million copies of its educational materials, translated into two dozen languages at a sixth-to-eighth-grade reading level, since the program began in 2004. As an independent, neutral organization rather than a commercial vendor, CISCRP occupies a distinctive position in the recruitment and retention landscape, working directly with pharmaceutical companies, CROs, and sponsor organizations on patient engagement and clinical trial education initiatives.

Mural Health

Mural Health's flagship platform, Mural Link, was built by a founder who invented the industry's first participant payment technology, the ClinCard, in 2008, and has since evolved into what the company calls the first comprehensive participant management platform in clinical research, combining payments, travel coordination, tax management, and site-participant communication. Led by CEO Sam Whitaker and based in Berwyn, Pennsylvania, the company reports its platform has driven a 60 percent reduction in trial dropout rates by removing financial and logistical barriers to participation. In March 2025, Mural Health announced a partnership with ICON plc, a top global CRO, to bring Mural Link's participant payment and travel tools to ICON's client base, and in February 2026 the company expanded its global payment capabilities to deliver reimbursements through local banking systems and digital wallets across markets including Latin America, Ukraine, and China. Mural Link offers more than 10 fee-free payment methods, including what the company says is the industry's only fee-free prepaid debit card for trial participants.

Patient Partner

PatientPartner connects new patients considering a treatment with trained mentors who have already been through a similar diagnosis or procedure, aiming to improve treatment starts and long-term adherence through peer-to-peer support rather than one-way educational content. Co-founded by Patrick Frank and George Kramb, both Forbes 30 Under 30 honorees, the company raised a $7 million Series Seed round in 2024 led by LionBird and FCA Venture Partners to expand its platform, which had grown to more than 40,000 users and over 500 mentors across a wide range of disease states and treatment types by the time of the raise. PatientPartner reports that patients who engage with a mentor are 68 percent more likely to begin a prescribed treatment, and the company's platform exceeds HIPAA, SOC 2, and ISO 27001 security standards. The company positions its mentorship model as complementary to, rather than competing with, traditional patient support hub services, integrating into a sponsor's existing marketing and patient services infrastructure.

Reverba

Reverba traces its roots to 2002, when it began as Health Perspectives Group before merging with sister companies Health Advocacy Strategies and Patient Health Perspectives and rebranding as Reverba in 2021, then acquiring medical communications firm Six Degrees Medical in 2025 to become Reverba Global. The Seattle-based company's proprietary reverbaBRIDGE platform, comprising reverbaLINK for recruitment pathway design, reverbaPULSE for real-time patient feedback, and reverbaALUM for post-trial alumni engagement, has supported more than 100 Phase 2/3 programs and 49 post-marketing studies, training over 12,000 investigators and site staff. In October 2025, Reverba launched ClinOps G.P.S., an operations platform aimed at giving sponsors end-to-end trial readiness and stakeholder governance to improve retention, which the company says demonstrated measurable retention gains in an implementation with a top-15 global pharmaceutical company. Reverba also maintains Health Stories Project, a community of more than 160,000 members willing to share personal health experiences, which the company draws on for patient pre-screening and trial site matching.

Ripple Science (EnrollNow)

Ripple Science, which has recently rebranded to EnrollNow, was founded in 2016 in Ann Arbor, Michigan and built a HIPAA-compliant software platform used by research investigators at more than 100 academic and for-profit sites, including Johns Hopkins University, UCLA, and Pennsylvania State University. Led by CEO Peter Falzon, the company reported in a 2021 white paper that its flagship product achieved 96 percent clinical trial patient retention for customers using the platform, and it has tracked more than one million clinical trial participant events across six countries. The platform centralizes a searchable patient registry, automated prescreening, scheduling, and communication tools into one system, replacing the spreadsheets many research sites previously relied on to track study participants. In 2024, the company partnered with Purdue University's College of Health and Human Sciences to build a central registry of research participants serving more than 250 faculty members and their teams.

Serva Health

Serva Health runs what it describes as the only multilingual, nurse-staffed call center dedicated specifically to recruiting, engaging, and retaining clinical trial patients worldwide, pairing that live nurse support with ServaCore, a proprietary, SOC II Type 2-audited technology platform built entirely in-house by the company's own engineering team. Based in Mount Laurel, New Jersey and led by President and CEO Lucine King, the company's nurses review medical records as part of pre-screening, helping determine which patients may qualify for a study before referral to a site, which the company says significantly reduces the burden on site staff. ServaCore integrates digital media campaigns, study websites with built-in pre-screening, site portals, patient mobile apps, and omnichannel communications into a single reporting system, giving sponsors real-time visibility into every patient's status in the recruitment pipeline. Serva Health's retention programs include appointment and dosing reminders, milestone messages, and structured lost-to-follow-up outreach delivered by the same nurses who handled a patient's initial recruitment.

Spencer Health Solutions

Spencer Health Solutions was founded by CEO Tom Rhoads after he witnessed the difficulty his father faced managing a complex medication regimen while being treated for glioblastoma, leading Rhoads to build the spencer SmartHub, an FDA-certified Class I medical device that dispenses pre-packaged medications, hosts telehealth visits, and collects real-world patient data from a patient's own home. Based in Morrisville, North Carolina, the company reports patients using spencer show 97 percent daily medication adherence across a range of diseases and medications, alongside patient engagement rates exceeding 90 percent for survey response, both well above typical phone or email-based outreach. In 2021, Otsuka Pharmaceutical Development & Commercialization entered an agreement to use the spencer SmartHub across both clinical trial and commercial applications, and the company has continued expanding its Spencer-Certified Pharmacy Partner Network to bring the device to patients through specialty pharmacy channels. A companion mobile app, spencerAssist, extends the device's medication reminders, survey collection, and telehealth access to patients while they're away from home.

Explore the full Recruitment & Retention landscape

The companies above represent a portion of a much larger field.

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This article is intended as an informational overview of vendors operating in this space. Inclusion on this list does not constitute an endorsement, recommendation, or qualification by Diligent.