2026 Patient Recruitment Roundup
What 10,180 completed patient trials say about enrollment,
2022–2025
REAL DATA. CLEARER INSIGHTS. BETTER OUTCOMES.
Patient recruitment keeps getting more complex
Delays in patient recruitment are the leading cause of trial timeline overruns, accounting for an estimated 80% of study delays. Oncology and rare disease trials draw on narrow patient populations, early phase designs have grown more complex, and Phase II now takes 19–20 months to enroll, up from 12 in 2010.
The Patient Recruitment Roundup white paper analyzes 19,880 completed industry-sponsored Phase I–IV trials, including 10,180 patient trials, from 2022 to 2025. It reports enrollment rates and durations by phase, therapeutic area, region, and drug modality, so your team can plan with current benchmarks. Start with the one-page summary below, then download the full report.
The key insights on one page
- MER hit a four-year low of 0.32 in 2024 and recovered only to 0.36 in 2025.
- Phase IV leads at a MER of 0.70–1.04. Oncology and rare disease trail at 0.16–0.22.
- Phase I enrollment time more than doubled, from 7.9 months to 16.8–20.3.
- Small molecules enroll 21–35% faster per site than biologics.
- Infectious disease vaccines post the highest and most volatile rates, up to a MER of 5.38 in 2025.
- Phase II site counts rose 30–40% while Phase II MER fell more than 50%.
Get the benchmarks behind the headlines
- MER by phase, therapeutic area, region, and modality
- Enrollment durations and site counts by phase
- Seven findings, each with a planning implication
Download the white paper
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12 insights to put the data to work
Citeline experts turned the findings of the 2026 Patient Recruitment Roundup into 12 actions for sponsors and CROs, including:
- Build enrollment forecasts around comparable studies
- Validate patient access before adding sites
- Establish a course-correction plan before launch
- Look at the longitudinal patient journey
Find the right patients. Get them enrolled.
Citeline brings together real-world patient intelligence, precision identification, and targeted activation to help your team build a recruitment strategy around real patient data.
Understand the patient landscape
Size and locate the eligible population, map referral pathways, and understand how patients reach care, before a single site is activated.
Build your patient access strategy
Connect patients to the providers and sites that serve them. Identify high-volume HCPs treating your population who aren't yet trial-engaged.
Activate protocol-matched patients
With a continuously running algorithm, surface matched patients earlier in their care journey via targeted HCP alerts and direct-to-patient outreach.
Check out our full suite of patient engagement and recruitment solutions.
Learn moreTalk to our Patient Engagement & Recruitment team
Bring your protocol and timeline. Our specialists will match you with the right Citeline Connect and Citeline PatientMatch support for your study.
Talk to a PE&R specialist
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