Only 3.6 percent of adult cancer patients enrolled in clinical trials recently. Their enrollment patterns reveal contradictions, like an 85 percent rate for children under 14 compared to 45 percent for teenagers.
Key Takeaways
- Adults over 65 years enrolled at 25% rate of those under 65 in phase III trials 2010-2020
- Women comprised 62% of breast cancer trial participants but only 38% in lung cancer trials in 2019
- Patients aged 18-39 had 1.8% participation vs. 4.2% for 40-64 in 2017 surveys
- In 2020, only 3.6% of adult cancer patients in the US enrolled in therapeutic clinical trials
- From 2000-2017, the overall participation rate in NCI-sponsored trials was 2.5% among US cancer patients
- Pediatric cancer trial participation reached 70% for eligible patients in Children's Oncology Group studies in 2019
- 62% of US cancer centers are in urban areas, leading to 3x lower rural participation
- Travel distance >50 miles reduced enrollment by 35% in NCI Community Oncology Research Program
- In Appalachia, trial participation was 1.1% vs. national 3.4% average in 2018
- Black patients comprised only 5% of participants in SWOG trials from 2010-2020 despite 13% cancer incidence
- Hispanic patients represented 4.2% in NCI trials 2010-2019, while comprising 19% of US population
- Asian Americans made up 2.1% of phase I-III trial participants in 2018
- Patients with annual income below $50,000 had 40% lower odds of trial participation
- Uninsured patients participated at 1.2% rate vs. 4.1% for privately insured in 2017 data
- Medicaid enrollees showed 2.3 times lower participation than Medicare patients in oncology trials
Participation in cancer trials remains low and inequitable, with age, sex, and location disparities limiting enrollment.
Related reading
01 · Category
Age and Gender Differences20 stats
01
Adults over 65 years enrolled at 25% rate of those under 65 in phase III trials 2010-2020
02
Women comprised 62% of breast cancer trial participants but only 38% in lung cancer trials in 2019
03
Patients aged 18-39 had 1.8% participation vs. 4.2% for 40-64 in 2017 surveys
04
Men over 70 underrepresented by 40% in prostate cancer trials despite high incidence
05
Pediatric trials saw 85% enrollment for ages 0-14 vs. 45% for adolescents 15-19 in 2022
06
Elderly (75+): 12% of trial participants despite 40% diagnoses
07
Gender imbalance in GI trials: 55% male vs. 45% female 2015-2020
08
Young adults (18-39): 2.1% overall participation 2018
09
Women underrepresented in bladder cancer trials by 25%
10
Teens (15-19) accrual: 52% of COG targets in 2021
11
80+ year olds: 8% enrollment despite 25% diagnoses
12
Males in breast cancer trials: 1.2% despite 1% incidence
13
Children 0-4: 92% COG accrual 2020
14
Females in pancreatic trials: 48% vs. 52% male 2016-2021
15
AYA (15-39): 1.5% of all cancer trial slots 2019
16
65-74 age group: 32% of participants 2021
17
Males dominate liver cancer trials 78%
18
Infants <1 year: 88% enrollment in rare trials
19
Gender parity improving: 51% female overall 2022
20
Seniors 70+: comorbidity exclusion 42% cases
Interpretation
Age and Gender Differences Interpretation
Our clinical trial enrollment is a masterclass in contradictions: while we meticulously recruit infants and approach gender parity on paper, we systematically exclude the elderly who bear the greatest cancer burden, treat young adults as statistical ghosts, and let disease-specific enrollment gaps persist like stubborn, life-threatening typos.
02 · Category
General Participation Rates25 stats
01
In 2020, only 3.6% of adult cancer patients in the US enrolled in therapeutic clinical trials
02
From 2000-2017, the overall participation rate in NCI-sponsored trials was 2.5% among US cancer patients
03
Pediatric cancer trial participation reached 70% for eligible patients in Children's Oncology Group studies in 2019
04
In phase III cancer trials from 2011-2020, average accrual was 68% of target, taking 3.2 years on average
05
US cancer clinical trial enrollment dropped to 1.8% during COVID-19 peak in 2020
06
In 2021, NCI trials showed 28% enrollment from patients over 70, up from 20% in 2010
07
Phase I trials had 5.2% participation rate among advanced cancer patients in 2018
08
Community-based trials enrolled 1.9% vs. 5.1% academic centers in 2019
09
Lung cancer trials averaged 512 participants per trial from 2015-2020
10
Overall US adult oncology trial accrual was 27,000 patients annually pre-COVID
11
Basket trials saw 4.1% enrollment rise 2017-2022
12
Immunotherapy trials: 6.3% participation among eligible 2020
13
45% of trials failed to meet accrual in under 2 years 2019
14
Precision medicine trials: 3.8% uptake in metastatic cancers
15
Global trials: US contributes 60% of participants 2021 data
16
Master protocols accelerated accrual by 12% in 2022
17
CAR-T trials: 7.2% eligible participation 2021
18
32% trials amended targets due to slow accrual 2018
19
Head/neck cancer: 2.9% participation rate 2020
20
International collaboration boosted enrollment 25% per trial
21
NCI MATCH trial: 4.5% screen-to-enroll success 2019
22
PROACTIVE initiative raised community accrual 11%
23
58% phase II trials closed early for poor accrual 2020
24
Leukemia trials: 8.4% pediatric participation 2021
25
EU-US trials: 45% faster accrual than domestic
Interpretation
General Participation Rates Interpretation
America's cancer trial system is a paradoxical landscape where children show us the future with 70% participation, while adults, who could benefit most from scientific progress, are stuck at a dismally consistent 3%, with logistical hurdles, geographic disparities, and a pandemic-induced drop proving that our greatest obstacle to curing cancer isn't always the science, but the system designed to deliver it.
03 · Category
Geographic and Access Issues20 stats
01
62% of US cancer centers are in urban areas, leading to 3x lower rural participation
02
Travel distance >50 miles reduced enrollment by 35% in NCI Community Oncology Research Program
03
In Appalachia, trial participation was 1.1% vs. national 3.4% average in 2018
04
Telehealth interventions increased remote enrollment by 22% during 2020-2021
05
Southern US states had 1.9% participation rate vs. 4.2% in Northeast in 2019 data
06
Patients >100 miles from site: 42% non-enrollment rate
07
Midwest rural enrollment: 1.4% vs. 3.9% urban 2017-2021
08
Lack of local trials: 68% barrier in underserved areas 2020
09
Mobile units boosted enrollment 18% in remote areas 2022 trial
10
Western states participation: 2.8% vs. 1.7% in South 2019
11
Frontier areas (low population density): 0.8% enrollment 2019
12
Northeast urban: 5.1% vs. Southwest rural 1.2% 2021
13
No trials within 75 miles for 25% rural patients
14
Virtual screening raised enrollment 15% in 2022 pilots
15
Pacific territories: <0.5% US trial participation 2018
16
Travel burden >2 hours: 51% decline rate 2020
17
Alaska Natives rural: 0.7% participation 2018
18
Trial deserts in 15% US counties 2022 map
19
Decentralized trials: 28% accrual improvement 2023 data
20
Border states higher Hispanic enrollment 3.1%
Interpretation
Geographic and Access Issues Interpretation
Cancer trials are building a far better future, but we seem to have forgotten to pave the roads to get there.
More related reading
04 · Category
Racial and Ethnic Disparities20 stats
01
Black patients comprised only 5% of participants in SWOG trials from 2010-2020 despite 13% cancer incidence
02
Hispanic patients represented 4.2% in NCI trials 2010-2019, while comprising 19% of US population
03
Asian Americans made up 2.1% of phase I-III trial participants in 2018
04
Native American/Alaska Native patients enrolled at 0.3% rate in cancer trials 2004-2016
05
In breast cancer trials, Black women enrollment was 7.5% vs. 12.4% white women from 2011-2018
06
African American men in prostate cancer trials: 8.2% enrollment despite 20% higher mortality
07
Latinos in colorectal cancer trials: 3.7% vs. 11% incidence share 2012-2019
08
South Asian subgroup in trials: 0.8% participation in 2020 meta-analysis
09
American Indian patients in NCI trials: 0.2% from 2000-2018
10
Black women in ovarian trials: 5.1% enrollment 2010-2020
11
Whites: 80% of trial participants despite 75% cancer cases
12
Pacific Islanders: 0.1% in NCI database 2010-2020
13
Multiracial patients: 1.2% enrollment 2018
14
Hispanic blacks: 0.4% in melanoma trials
15
Asians in liver cancer: 15% enrollment matching incidence
16
Recruitment strategies improved black enrollment by 14% 2021
17
Non-Hispanic whites: 84% in CAR-T trials 2020
18
Middle Eastern/North African: 0.6% reported 2019
19
Enrollment disparities narrowed 2% yearly for Hispanics 2015-2020
20
Blacks in MM trials: 4.8% 2012-2021
Interpretation
Racial and Ethnic Disparities Interpretation
It seems clinical trials are serving a demographic sampler platter where everyone gets a taste except, disproportionately, the very communities bearing a heavier burden of the disease.
05 · Category
Socioeconomic Factors20 stats
01
Patients with annual income below $50,000had 40% lower odds of trial participation
02
Uninsured patients participated at 1.2% rate vs. 4.1% for privately insured in 2017 data
03
Medicaid enrollees showed 2.3 times lower participation than Medicare patients in oncology trials
04
Low education (high school or less) correlated with 55% reduced trial enrollment likelihood
05
Rural patients had 28% lower enrollment rates than urban counterparts in 2015-2020 trials
06
Household income <$30k: 52% less likely to enroll per 2016 study
07
Public insurance holders: 1.5% participation vs. 3.8% private in 2020
08
No high school diploma: 0.9% enrollment rate in surveys
09
Cost concerns cited by 47% of low-SES decliners in 2019 poll
10
Unemployment linked to 33% lower odds in multivariate analysis
11
Poverty rate >20% counties: 1.6% participation
12
College grads: 4.7x higher enrollment odds 2020
13
Transportation costs deterred 39% low-income
14
Blue-collar workers: 28% lower rate than white-collar
15
Food insecurity linked to 22% drop in willingness
16
Income $75k+: 5.1% participation 2017 survey
17
VA patients: 3.2% enrollment higher than average
18
Lost wages feared by 35% non-enrollees low-SES
19
Graduate degree: 6.2% participation rate
20
Housing instability: 19% barrier in qualitative study
Interpretation
Socioeconomic Factors Interpretation
It is a statistical truth as cold and clear as a chemotherapy drip: the single greatest predictor of whether a cancer patient will join a clinical trial is not the aggressiveness of their disease, but the weight of their wallet, the zip code of their home, and the line on their diploma.
Reference
Cite This Report
This report is designed to be cited. We maintain stable URLs and versioned verification dates. Copy the format appropriate for your publication below.
APA
Felix Zimmermann. (2026, February 13). Cancer Clinical Trial Participation Statistics. Gitnux. https://gitnux.org/cancer-clinical-trial-participation-statistics
MLA
Felix Zimmermann. "Cancer Clinical Trial Participation Statistics." Gitnux, 13 Feb 2026, https://gitnux.org/cancer-clinical-trial-participation-statistics.
Chicago
Felix Zimmermann. 2026. "Cancer Clinical Trial Participation Statistics." Gitnux. https://gitnux.org/cancer-clinical-trial-participation-statistics.
Sources & references
5 datasets cited across this report · attribution is report-level