Clinical Trials Key Facts and Trends

Explore the latest facts, figures and trends in clinical trials. This page brings together the key data on patient engagement and retention, enrolment and study volume, and research and development investment and market growth.

> Patient Engagement & Retention

> Enrollment & Studies

> R&D Investment

> Breakthroughs & Success Stories

01 | Clinical Trial Patient Engagement and Retention

Participation Matters—But Reporting Still Lags

Only 18% of published randomized controlled trial (RCT) articles reported Patient and Public Involvement (PPI).
Just 19% of trial protocols reported PPI.
Recognition of PPI contributions appeared in 58% of articles but only 32% of protocols.

Source: BMJ, April 2025

Recruitment & Retention Challenges

11% of research sites fail to enroll a single patient—a notable improvement from 20% in earlier years.
The median retention rate in publicly funded RCTs: 88%.
The median consent rate: 72%.
Final recruitment targets achieved in 63% of RCTs.

Source: BMJ Open

What Patients Want

73% prefer to hear about trials directly from their doctor’s office.
7% of oncology patients and 90.4% of chronic disease patients say speaking with researchers is critical.
Only 5% learn about trials through online communities.
44% find traveling to clinics burdensome, up from 29% in 2019.
Half of participants want telemedicine and virtual visits to stay.

Source: ACRP

02 | Clinical Trial Enrolment and Study Volume

A Growing Landscape

As of July 2025, there are 543,515 registered studies globally.
- 76% are interventional.
- 22,631 new studies were registered in just the first half of 2025.
The U.S. accounts for 29% of all registered studies; non-U.S. locations for 56%.

Source: ClinicalTrials.gov

Enrollment Trends

UK recruitment to clinical trials in 2023/24 totaled 349,019
Annual recruitment to industry trials in the UK rose by 15%, reaching 42,088
Small molecule trial starts in Phase III declined from 65% in 2015 to 53% in 2024.

Source: Pharmaceutical Journal, IQVIA

03 | R and D Investment and Clinical Trials Market Growth

R&D Spending Reaches New Highs

Large pharma R&D spending rose from $163 billion (2023) to $190 billion (2024).
NIH clinical research funding topped $18.9 billion in 2023.
In the UK, pharma accounted for 18% of all business R&D investment—£9 billion in 2022 alone.

Source: IQVIA, ONS, NIH

Global Market Outlook

Global clinical trials market in 2023: $81.9 billion.
Market projected to reach $153.59 billion by 2033, growing at 49% CAGR.

Source: Nova One Advisor

04 | Why This Matters

The clinical trial landscape is evolving—fast. From decentralized trials to record-high R&D investments, the way new treatments are tested and delivered is transforming.

pRxEngage is here to help biopharma, research sites, and patient advocates connect people to studies that matter.

Explore our platform to see how we make trial matching easier, smarter, and more human.