GITNUXREPORT 2026

Clinical Trial Enrollment Statistics

Clinical trial enrollment faces severe delays and diversity gaps despite new recruitment strategies.

Rajesh Patel

Team Lead & Senior Researcher with over 15 years of experience in market research and data analytics.

First published: Feb 13, 2026

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Statistic 1

Patient-centric strategies increased retention by 20%

Statistic 2

Transportation barriers cited by 40% of non-participants

Statistic 3

Mistrust in pharma: 30% decline reason among minorities

Statistic 4

Awareness gap: 75% unaware of local trials

Statistic 5

Time commitment deters 35% potential enrollees

Statistic 6

Reimbursement issues affect 25% site performance

Statistic 7

Regulatory burden delays site initiation by 3 months

Statistic 8

Physician reluctance: 50% don't discuss trials

Statistic 9

Digital divide excludes 20% rural patients

Statistic 10

Language barriers impact 15% Hispanic eligibility

Statistic 11

Fear of side effects: 28% top concern

Statistic 12

Site turnover: 30% annual, disrupts enrollment

Statistic 13

Protocol complexity causes 40% screen failures

Statistic 14

Insurance coverage gaps for 18% participants

Statistic 15

Pandemic travel restrictions: 60% enrollment drop Q2 2020

Statistic 16

Caregiver burden for elderly: 22% barrier

Statistic 17

Stigma in mental health trials: 45% avoidance

Statistic 18

Budget constraints delay 35% of site startups

Statistic 19

Eligibility criteria too strict: excludes 70% patients

Statistic 20

Lack of diversity training for sites: 50% issue

Statistic 21

Work schedule conflicts: 32% for working-age adults

Statistic 22

Poor communication from sponsors: 40% site complaint

Statistic 23

High screen failure rate 40% in oncology

Statistic 24

No compensation: deters 25% low-income

Statistic 25

African Americans comprise 5% of trial participants despite 13% U.S. population

Statistic 26

Women represent 42% of cardiovascular trial enrollees

Statistic 27

Hispanics/Latinos are 1% of Alzheimer’s trial participants

Statistic 28

Elderly (65+) are 25% of trial participants but 16% of population

Statistic 29

Asian Americans: 2% in oncology trials vs. 6% population

Statistic 30

Children under 18: only 1.4% of all trial enrollees globally

Statistic 31

Rural residents: 5% of U.S. trial participants despite 20% population

Statistic 32

LGBTQ+ individuals: less than 1% represented in trials

Statistic 33

Low-income participants: 10% enrollment despite 30% eligibility

Statistic 34

Native Americans: 0.4% of diabetes trial enrollees

Statistic 35

2023 diversity mandates increased minority enrollment by 12%

Statistic 36

Black participants: 5.2% in sickle cell trials vs. 95% affected

Statistic 37

Women in Phase I oncology: 38%

Statistic 38

Veterans: underrepresented at 2% in mental health trials

Statistic 39

Pregnant individuals: excluded from 90% of trials

Statistic 40

Immigrants/refugees: <1% in infectious disease trials

Statistic 41

65-74 age group: 30% of enrollees in immunology trials

Statistic 42

Pacific Islanders: 0.2% in obesity trials

Statistic 43

Disability status: 15% reported in trials vs. 25% population

Statistic 44

Urban vs. rural: 85-15% split in enrollment

Statistic 45

Gen Z (18-24): only 8% in dermatology trials

Statistic 46

Transgender participants: 0.1% across trials

Statistic 47

2022: Black women 4% in breast cancer trials

Statistic 48

Middle Eastern ethnicity: 1% in U.S. trials

Statistic 49

75+ age: 12% enrollment in cardiology trials

Statistic 50

Socioeconomic status low: 18% in vaccine trials

Statistic 51

Hispanic men: 3% in prostate cancer trials

Statistic 52

Asian women: 7% in osteoporosis studies

Statistic 53

In Phase I trials, 75% of participants are male

Statistic 54

In 2022, only 11% of clinical trial sites enrolled more than 85% of their target patients

Statistic 55

Average clinical trial enrollment delay is 4.5 months beyond original timelines

Statistic 56

85% of trials experience enrollment delays

Statistic 57

In oncology trials, median enrollment time is 18 months

Statistic 58

30% of trials fail to reach 80% enrollment target

Statistic 59

U.S. trials enroll patients 28% faster than European sites

Statistic 60

COVID-19 disrupted 80% of ongoing trials' enrollment in 2020

Statistic 61

Decentralized trials reduced enrollment time by 25% in 2023 pilots

Statistic 62

Phase III trials take 20 months on average to fully enroll

Statistic 63

62% of sponsors report enrollment as top challenge

Statistic 64

Global enrollment rates dropped 15% during pandemic peaks

Statistic 65

Rare disease trials enroll 50% slower than common diseases

Statistic 66

Mobile apps boosted enrollment by 35% in digital trials

Statistic 67

70% of trials extend timelines by at least 6 months for enrollment

Statistic 68

U.K. sites enroll 1.8 patients per month per trial on average

Statistic 69

AI predictive models cut enrollment delays by 40%

Statistic 70

Pediatric trials enroll 4 times slower than adult trials

Statistic 71

2023 saw 25% increase in trial activations but flat enrollment

Statistic 72

Community sites enroll 2x faster than academic centers

Statistic 73

Virtual screening enrolled 50,000 participants in 3 months for COVID trials

Statistic 74

45% of trials close early due to poor enrollment

Statistic 75

Median patients per site is 3.2 in Phase II trials

Statistic 76

Blockchain tech improved enrollment verification speed by 60%

Statistic 77

Eastern Europe sites enroll 40% more efficiently than Western Europe

Statistic 78

55% of biotech trials face severe enrollment hurdles

Statistic 79

Patient registries accelerated enrollment by 30% in 50 trials

Statistic 80

Wearables enabled 20% faster screening-to-enrollment

Statistic 81

2021 oncology enrollment shortfall was 20% of targets

Statistic 82

Hybrid trials enrolled 15% more diverse patients faster

Statistic 83

Global average enrollment rate is 0.5 patients/site/month

Statistic 84

Phase III trials enroll 40% more females than Phase I

Statistic 85

Phase II oncology: average 150 patients enrolled

Statistic 86

Phase IV post-marketing: 500+ patients average

Statistic 87

90% of Phase I trials complete enrollment on time

Statistic 88

Phase III rare disease: median 200 patients after 3 years

Statistic 89

Phase I healthy volunteers: 95% enrollment rate

Statistic 90

Phase II neurology: 120 patients average

Statistic 91

Only 20% of Phase III trials enroll ahead of schedule

Statistic 92

Phase Ib/II combo trials: 80 patients median

Statistic 93

Phase 0 microdosing: 10-20 patients

Statistic 94

Adaptive Phase II/III: enrollment 25% faster

Statistic 95

Phase III cardiology: 1,000-5,000 patients average

Statistic 96

Phase I pediatrics: 12-30 patients typical

Statistic 97

Seamless Phase II/III: reduced enrollment by 30%

Statistic 98

Phase IV observational: 10,000+ enrollees common

Statistic 99

Phase II immunology: 200 patients median

Statistic 100

70% Phase I trials in healthy volunteers only

Statistic 101

Phase III global trials: 3,000 patients average

Statistic 102

Basket Phase II: 50-100 per basket

Statistic 103

Umbrella trials Phase II: 300 total enrollees

Statistic 104

Long-term Phase IV: 2 years to enroll 1,500

Statistic 105

Oncology dominates Phase I with 40% of trials

Statistic 106

Phase III vaccine trials: 30,000+ participants

Statistic 107

Oncology Phase III: enrolls 60% of all oncology patients in trials

Statistic 108

Rare disease Phase I/II: average 25 patients

Statistic 109

Phase II diabetes: 400 patients median

Statistic 110

Oncology accounts for 35% of all Phase III enrollments

Statistic 111

Cardiovascular trials enroll 15% of total patients annually

Statistic 112

Neurology trials: 10% of global enrollment, Alzheimer's 20% within

Statistic 113

Infectious diseases: 25% enrollment spike in 2020-2022

Statistic 114

Rare diseases: only 5% of total trial patients despite 7% prevalence

Statistic 115

Immunology/autoimmune: 12% of Phase III enrollments

Statistic 116

Diabetes/endocrinology: 8% of annual enrollments

Statistic 117

Psychiatry: 6% enrollment, depression trials 40% thereof

Statistic 118

Pulmonology: 7% post-COVID focus

Statistic 119

Dermatology: 4% of trials, psoriasis leading at 25%

Statistic 120

Hematology: 9% enrollment in oncology subset

Statistic 121

Gastroenterology: 5% total, IBD 50%

Statistic 122

Orthopedics: 3% enrollment, osteoarthritis dominant

Statistic 123

Nephrology: 4% of trials, CKD trials 60%

Statistic 124

Ophthalmology: 2.5% enrollment, AMD leading

Statistic 125

Vaccines (non-COVID): 5% baseline

Statistic 126

Pediatrics cross-area: 2% total enrollment

Statistic 127

Women's health: 3% outside oncology

Statistic 128

Pain management: 2% enrollment, chronic pain 70%

Statistic 129

Devices (not pharma): 10% of interventional trials enrollment

Statistic 130

Metabolic disorders: 6% , obesity trials surging 50%

Statistic 131

ENT/otolaryngology: 1.5%, hearing loss focus

1/131

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Imagine a system designed to save lives that consistently falls short, as in 2022 only 11% of clinical trial sites successfully enrolled more than 85% of their target patients, a stark statistic that highlights the profound enrollment crisis delaying medical breakthroughs.

Key Takeaways

In 2022, only 11% of clinical trial sites enrolled more than 85% of their target patients
Average clinical trial enrollment delay is 4.5 months beyond original timelines
85% of trials experience enrollment delays
African Americans comprise 5% of trial participants despite 13% U.S. population
Women represent 42% of cardiovascular trial enrollees
Hispanics/Latinos are 1% of Alzheimer’s trial participants
Phase III trials enroll 40% more females than Phase I
Phase II oncology: average 150 patients enrolled
Phase IV post-marketing: 500+ patients average
Oncology accounts for 35% of all Phase III enrollments
Cardiovascular trials enroll 15% of total patients annually
Neurology trials: 10% of global enrollment, Alzheimer's 20% within
Patient-centric strategies increased retention by 20%
Transportation barriers cited by 40% of non-participants
Mistrust in pharma: 30% decline reason among minorities

Clinical trial enrollment faces severe delays and diversity gaps despite new recruitment strategies.

Barriers and Challenges

Patient-centric strategies increased retention by 20%
Transportation barriers cited by 40% of non-participants
Mistrust in pharma: 30% decline reason among minorities
Awareness gap: 75% unaware of local trials
Time commitment deters 35% potential enrollees
Reimbursement issues affect 25% site performance
Regulatory burden delays site initiation by 3 months
Physician reluctance: 50% don't discuss trials
Digital divide excludes 20% rural patients
Language barriers impact 15% Hispanic eligibility
Fear of side effects: 28% top concern
Site turnover: 30% annual, disrupts enrollment
Protocol complexity causes 40% screen failures
Insurance coverage gaps for 18% participants
Pandemic travel restrictions: 60% enrollment drop Q2 2020
Caregiver burden for elderly: 22% barrier
Stigma in mental health trials: 45% avoidance
Budget constraints delay 35% of site startups
Eligibility criteria too strict: excludes 70% patients
Lack of diversity training for sites: 50% issue
Work schedule conflicts: 32% for working-age adults
Poor communication from sponsors: 40% site complaint
High screen failure rate 40% in oncology
No compensation: deters 25% low-income

Barriers and Challenges Interpretation

While clinical trials are built on the promise of scientific progress, their success often hinges on the very human details of trust, access, and logistics that, if ignored, can turn a study protocol into a masterclass in how not to find participants.

Demographics and Diversity

African Americans comprise 5% of trial participants despite 13% U.S. population
Women represent 42% of cardiovascular trial enrollees
Hispanics/Latinos are 1% of Alzheimer’s trial participants
Elderly (65+) are 25% of trial participants but 16% of population
Asian Americans: 2% in oncology trials vs. 6% population
Children under 18: only 1.4% of all trial enrollees globally
Rural residents: 5% of U.S. trial participants despite 20% population
LGBTQ+ individuals: less than 1% represented in trials
Low-income participants: 10% enrollment despite 30% eligibility
Native Americans: 0.4% of diabetes trial enrollees
2023 diversity mandates increased minority enrollment by 12%
Black participants: 5.2% in sickle cell trials vs. 95% affected
Women in Phase I oncology: 38%
Veterans: underrepresented at 2% in mental health trials
Pregnant individuals: excluded from 90% of trials
Immigrants/refugees: <1% in infectious disease trials
65-74 age group: 30% of enrollees in immunology trials
Pacific Islanders: 0.2% in obesity trials
Disability status: 15% reported in trials vs. 25% population
Urban vs. rural: 85-15% split in enrollment
Gen Z (18-24): only 8% in dermatology trials
Transgender participants: 0.1% across trials
2022: Black women 4% in breast cancer trials
Middle Eastern ethnicity: 1% in U.S. trials
75+ age: 12% enrollment in cardiology trials
Socioeconomic status low: 18% in vaccine trials
Hispanic men: 3% in prostate cancer trials
Asian women: 7% in osteoporosis studies
In Phase I trials, 75% of participants are male

Demographics and Diversity Interpretation

Our clinical trial enrollment statistics paint a depressingly exclusive portrait of modern medicine, where the promise of universal benefit is routinely tested on a startlingly narrow slice of humanity.

Enrollment Rates and Timelines

In 2022, only 11% of clinical trial sites enrolled more than 85% of their target patients
Average clinical trial enrollment delay is 4.5 months beyond original timelines
85% of trials experience enrollment delays
In oncology trials, median enrollment time is 18 months
30% of trials fail to reach 80% enrollment target
U.S. trials enroll patients 28% faster than European sites
COVID-19 disrupted 80% of ongoing trials' enrollment in 2020
Decentralized trials reduced enrollment time by 25% in 2023 pilots
Phase III trials take 20 months on average to fully enroll
62% of sponsors report enrollment as top challenge
Global enrollment rates dropped 15% during pandemic peaks
Rare disease trials enroll 50% slower than common diseases
Mobile apps boosted enrollment by 35% in digital trials
70% of trials extend timelines by at least 6 months for enrollment
U.K. sites enroll 1.8 patients per month per trial on average
AI predictive models cut enrollment delays by 40%
Pediatric trials enroll 4 times slower than adult trials
2023 saw 25% increase in trial activations but flat enrollment
Community sites enroll 2x faster than academic centers
Virtual screening enrolled 50,000 participants in 3 months for COVID trials
45% of trials close early due to poor enrollment
Median patients per site is 3.2 in Phase II trials
Blockchain tech improved enrollment verification speed by 60%
Eastern Europe sites enroll 40% more efficiently than Western Europe
55% of biotech trials face severe enrollment hurdles
Patient registries accelerated enrollment by 30% in 50 trials
Wearables enabled 20% faster screening-to-enrollment
2021 oncology enrollment shortfall was 20% of targets
Hybrid trials enrolled 15% more diverse patients faster
Global average enrollment rate is 0.5 patients/site/month

Enrollment Rates and Timelines Interpretation

It seems the clinical trial ecosystem is stuck in a chronic condition of ambitious targets meeting the stubborn reality of patient recruitment, where only a fraction of sites perform and delays have become an expensive, industry-wide symptom rather than a surprise.

Phase-specific Enrollment

Phase III trials enroll 40% more females than Phase I
Phase II oncology: average 150 patients enrolled
Phase IV post-marketing: 500+ patients average
90% of Phase I trials complete enrollment on time
Phase III rare disease: median 200 patients after 3 years
Phase I healthy volunteers: 95% enrollment rate
Phase II neurology: 120 patients average
Only 20% of Phase III trials enroll ahead of schedule
Phase Ib/II combo trials: 80 patients median
Phase 0 microdosing: 10-20 patients
Adaptive Phase II/III: enrollment 25% faster
Phase III cardiology: 1,000-5,000 patients average
Phase I pediatrics: 12-30 patients typical
Seamless Phase II/III: reduced enrollment by 30%
Phase IV observational: 10,000+ enrollees common
Phase II immunology: 200 patients median
70% Phase I trials in healthy volunteers only
Phase III global trials: 3,000 patients average
Basket Phase II: 50-100 per basket
Umbrella trials Phase II: 300 total enrollees
Long-term Phase IV: 2 years to enroll 1,500
Oncology dominates Phase I with 40% of trials
Phase III vaccine trials: 30,000+ participants
Oncology Phase III: enrolls 60% of all oncology patients in trials
Rare disease Phase I/II: average 25 patients
Phase II diabetes: 400 patients median

Phase-specific Enrollment Interpretation

While Phase III trials enroll thousands like a well-organized army, nearly three-quarters of Phase I studies are still limited to small, healthy platoons, highlighting the persistent gulf between early safety checks and the final large-scale battle for efficacy.

Therapeutic Area Enrollment

Oncology accounts for 35% of all Phase III enrollments
Cardiovascular trials enroll 15% of total patients annually
Neurology trials: 10% of global enrollment, Alzheimer's 20% within
Infectious diseases: 25% enrollment spike in 2020-2022
Rare diseases: only 5% of total trial patients despite 7% prevalence
Immunology/autoimmune: 12% of Phase III enrollments
Diabetes/endocrinology: 8% of annual enrollments
Psychiatry: 6% enrollment, depression trials 40% thereof
Pulmonology: 7% post-COVID focus
Dermatology: 4% of trials, psoriasis leading at 25%
Hematology: 9% enrollment in oncology subset
Gastroenterology: 5% total, IBD 50%
Orthopedics: 3% enrollment, osteoarthritis dominant
Nephrology: 4% of trials, CKD trials 60%
Ophthalmology: 2.5% enrollment, AMD leading
Vaccines (non-COVID): 5% baseline
Pediatrics cross-area: 2% total enrollment
Women's health: 3% outside oncology
Pain management: 2% enrollment, chronic pain 70%
Devices (not pharma): 10% of interventional trials enrollment
Metabolic disorders: 6% , obesity trials surging 50%
ENT/otolaryngology: 1.5%, hearing loss focus

Therapeutic Area Enrollment Interpretation

The grim reality of clinical research shows oncology rightfully consuming the lion’s share of focus, while the world's urgent and chronic crises—from infectious disease surges to neglected rare conditions—must claw for scraps of attention and patients amidst a brutal, data-driven triage of human suffering.

Sources & References

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