Why 85% of Global Trials Are Delayed (and How to Fix Recruitment)

Global clinical trials are essential for developing new therapies and advancing medical knowledge, yet 85% of clinical trials face delays that slow progress and increase costs. Delays in patient recruitment are one of the primary factors, but they are only part of a complex web of challenges affecting trial timelines. Efficient trial recruitment is critical not only for sponsors but also for patients waiting for innovative treatments. 

Multifaceted Drivers of Delay

While patient recruitment often receives the most attention, delays in global clinical trials stem from multiple sources. Site activation issues, regulatory approvals, contract negotiations, and logistical hurdles can each stall progress. For example, some trials must wait months for sequential ethics approvals from local Institutional Review Boards (IRBs) or ethics committees, significantly extending start-up timelines.

Contract and budget negotiations also contribute to delays. Before a site can begin recruiting patients, agreements must be carefully reviewed and signed, ensuring compliance with regulations and protecting both sponsors and participants. These administrative processes, while necessary, can add weeks or even months to trial initiation.

Site selection and readiness further influence timelines. Trials conducted at under-prepared sites or facilities with limited infrastructure often face obstacles such as incomplete documentation, inadequate staffing, or logistical constraints. 

Real-World Consequences

Delays in clinical trial start-up and recruitment have tangible consequences. Sponsors face higher costs and slower return on investment, while patients experience postponed access to potentially life-saving therapies. In addition, delays can compromise data quality and affect the reliability of study results, impacting both regulatory approval and future research planning.

For GPs and patients looking to contribute to meaningful research and participate in clinical trials efficiently, contact TrialChoices today at info@trialchoices.org to explore opportunities and streamline trial recruitment.

Why Recruitment (and Retention) Is Often the Weakest Link

Patient recruitment and retention are consistently cited as the most significant challenges in clinical trial recruitment. Across disease areas and regions, a majority of trials globally report difficulty enrolling participants and keeping them engaged throughout the study. These challenges can slow trial timelines, increase costs, and compromise data integrity, making recruitment and retention often the weakest link in successful clinical research.

Low Public Awareness and Limited Understanding

One of the primary barriers to patient recruitment is a lack of awareness or understanding of clinical trials. Many potential participants do not fully grasp what participation involves, from study requirements to potential risks and benefits. Misconceptions can reduce interest in joining trials, even for those who meet eligibility criteria. Effective recruitment strategies must include clear, accessible education about clinical studies to engage participants confidently. Utilising social media platforms can help raise awareness, provide accurate information, and reach diverse patient populations efficiently.

Complex Protocols and Strict Eligibility Criteria

Clinical drug studies often involve detailed protocols and strict inclusion and exclusion criteria. While these are necessary for safety and scientific rigour, they can limit the pool of eligible participants. Burdensome procedures, frequent visits, or invasive assessments can discourage potential participants from enrolling or remaining in a trial. Simplifying trial procedures where possible, providing flexible scheduling, and offering support for participants can improve retention and make recruitment more effective.

Geographical and Logistical Challenges

Distance from trial sites, limited transportation options, and resource constraints can further reduce recruitment and retention rates. Patients living far from study centers may struggle to attend appointments consistently, which can result in dropouts. Trial sponsors and sites that incorporate decentralised trial models, home visits, or virtual check-ins can overcome these barriers and make participation more convenient, ensuring better engagement and adherence.

High Dropout Rates and Amplified Delays

Even after successful enrollment, maintaining participant engagement remains challenging. High dropout rates disrupt data collection and can derail trial timelines, forcing sites to recruit additional participants. Recruitment and retention challenges also amplify other delays, leaving sites idle, extending regulatory windows, and increasing overall trial costs. By identifying barriers early and implementing targeted recruitment strategies, sponsors can mitigate these risks and maintain momentum in clinical drug trials.

Strategic Solutions — How to Fix Recruitment Problems and Accelerate Trials

Recruitment challenges remain one of the most significant obstacles in clinical trials, often resulting in delays, increased costs, and reduced trial success. Addressing these challenges strategically is essential to improving patient enrolment, enhancing retention, and ensuring trials meet their objectives efficiently. 

Design Trials with the Participant in Mind

Participant-focused trial design is fundamental to successful recruitment. When protocols consider the patient experience, participation becomes more manageable and appealing. Key strategies include:

• Simplifying procedures: Reduce the number of visits, tests, and administrative steps wherever possible.

• Expanding eligibility criteria: Safely broadening inclusion parameters can increase the pool of potential participants.

• Minimising patient burden: Consider flexible scheduling, remote monitoring, or telehealth visits.

These measures not only increase enrolment but also support retention and improve the quality of data collection. Patients are more likely to stay engaged when they feel their time and well-being are valued, directly contributing to overall trial success.

Broaden Recruitment Outreach and Awareness

Visibility is critical for attracting eligible participants. Recruitment efforts should extend beyond traditional channels and include:

• Digital outreach via social media, email campaigns, and online patient communities.

• Partnerships with patient advocacy groups and community organisations to improve trust and reach under-represented populations.

• Culturally sensitive messaging and educational materials to inform patients about trial objectives, benefits, and participation requirements.

  
  

Leverage Technology and Data Analytics

Modern technology and data-driven strategies streamline early patient identification and recruitment:

• Real-world data (RWD) and electronic health records (EHRs): Pre-screen participants efficiently and ensure eligibility alignment.

• Centralised databases: Provide easy access to potential candidate profiles.

• Predictive modelling and AI-driven matching: Accelerate identification of suitable participants and reduce manual workload.

These innovations allow research teams to identify high-potential participants quickly, reduce screen failures, and save both time and resources. Technology-driven recruitment improves operational efficiency and enhances trial success while maintaining ethical standards.

Prepare Sites Properly and Streamline Site Activation

Efficient site preparation is key to preventing delays in trial initiation. Ensuring sites are fully ready before recruitment begins reduces bottlenecks and increases participant satisfaction. Best practices include:

• Completing documentation, contracts, and regulatory paperwork in advance.

• Conducting site readiness assessments and training for research staff.

• Finalising budgets and ensuring necessary infrastructure is operational.

Proper site activation ensures recruitment can begin smoothly, contributing to faster enrolment and higher trial success.

Adopt Adaptive Trial Designs and Flexible Recruitment Strategies

Adaptive designs and flexible recruitment strategies help trials respond to real-world performance rather than relying solely on static projections. Strategies include:

• Maintaining backup sites for staggered recruitment.

• Conducting interim reviews to adjust recruitment targets dynamically.

• Implementing flexible scheduling and remote assessments for participants when feasible.

This approach improves enrolment efficiency, reduces delays, and ensures trials remain patient-centric, ethical, and representative.

Monitoring, Metrics & Continuous Improvement — Ensuring Trials Stay on Track

Successful clinical trials rely not only on careful planning but also on ongoing monitoring and continuous improvement. Sponsors and clinical teams must actively track recruitment, retention, and overall site performance to ensure trials stay on schedule, ethical, and representative. Real-time data enables teams to identify bottlenecks early and take corrective action, ultimately improving patient recruitment, trial efficiency, and outcomes.

Define Key Metrics and KPIs

Establishing clear metrics and key performance indicators (KPIs) is essential for understanding trial progress. Important KPIs include recruitment rate per site, screening-to-enrolment ratio, dropout rate, time from site activation to first patient in (FPI), average enrolment per month, and diversity/composition of the participant cohort. Monitoring these indicators helps sponsors assess patient recruitment effectiveness, site efficiency, and trial representativeness. Using these KPIs, teams can spot potential issues early and implement targeted interventions to maintain study integrity.

Establish Real-Time Monitoring Dashboards

Real-time monitoring dashboards are invaluable tools for tracking trial progress. By providing a centralised view of all key metrics, dashboards allow sponsors and clinical teams to detect early signs of recruitment shortfall or retention problems. They also support:

• Rapid identification of underperforming sites

• Early intervention to address recruitment bottlenecks

• Efficient resource reallocation and backup site activation

Visualising trial data in real time enables teams to act proactively, reducing delays and improving patient recruitment outcomes.

Emphasise Post-Trial Reviews and Feedback Loops

Continuous improvement requires systematic post-trial reviews. After completing a clinical trial, sponsors and contract research organisations (CROs) should analyse:

• Recruitment strategies and site performance

• Reasons for patient dropouts

• Operational challenges that affected timelines

Feedback loops ensure lessons learned from one trial inform future planning, enhancing efficiency, reducing risks, and optimising patient recruitment processes.

Adopt Adaptive Planning and Proactive Contingency

Adaptive planning is essential to managing uncertainty in clinical trials. Maintaining a pool of potential sites and patients, rapidly activating backup sites, and adjusting recruitment timelines proactively prevents repeated delays. Sponsors who anticipate obstacles and implement contingency plans can maintain trial momentum, meet recruitment targets, and uphold patient safety and ethical standards.

Patient-Centric Recruitment Made Simple

Patient recruitment and trial efficiency are critical to successful clinical research. TrialChoices bridges UK patients and GPs with global clinical trials, leveraging centrally coordinated patient data and clinical expertise to identify trial-ready participants efficiently. This innovative approach accelerates recruitment, reduces study timelines from months to weeks, and ensures high ethical standards. 

Join a network that makes clinical trials faster, safer, and more effective. Contact TrialChoices now at info@trialchoices.org and take the first step toward meaningful research participation for your patients or practice.