ClinicalTrials.gov now lists 448,316 clinical studies across 220 countries, and the balance of who sponsors them and where they happen is anything but even. Industry backs 55% of trials, while the US hosts 45%, yet outcomes and completion rates shift dramatically by phase, design, and therapeutic area. Let’s walk through the statistics that explain that mismatch and what it means for interpreting clinical evidence.
Key Takeaways
- Industry sponsors fund 55% of trials (246,000 studies), academia 25% (112,000), per ClinicalTrials.gov 2023 data
- United States hosts 45% of all trials (201,742 studies), followed by China at 12% (53,798)
- Europe (EU countries) accounts for 28% of registrations (125,528 studies) as of October 2023
- Globally, 42% of trials registered in 2022 were Phase 1, compared to 25% Phase 2 and 18% Phase 3
- Basket trials, a type of master protocol design, increased to 1,200 registrations by 2023, up 300% since 2015
- Randomized controlled trials (RCTs) account for 65% of interventional Phase 3 studies on ClinicalTrials.gov, totaling around 29,250 studies
- Only 45% of trials registered before 2005 have published results, per 2022 analysis of 100,000 studies
- Phase 3 trials have 75% completion rate within estimated timelines, based on 20,000 reviewed studies
- 82% of oncology Phase 3 trials report primary endpoint success, from 5,000 completed studies analyzed
- Oncology trials dominate with 22.4% of total registrations (100,000+ studies), followed by neurology at 10.2%
- Cardiovascular disease trials total 38,500 studies on ClinicalTrials.gov, accounting for 8.6% of interventional trials
- Infectious diseases, excluding COVID-19, have 25,000 trials, 5.6% of total, with vaccines comprising 40%
- As of October 2023, there are 448,316 clinical studies registered on ClinicalTrials.gov, spanning 220 countries and targeting over 3,900 conditions
- From 2000 to 2023, annual registrations on ClinicalTrials.gov increased from 3,000 to over 50,000 per year, representing a 16-fold growth
- In 2022, 66,000 new interventional trials were registered globally on ClinicalTrials.gov, with 40% from industry sponsors
Industry and the United States dominate ClinicalTrials.gov registrations, with interventional trials leading and early Phase 1 growth.
Related reading
01 · Category
Geographic and Sponsor18 stats
01
Industry sponsors fund 55% of trials (246,000 studies), academia 25% (112,000), per ClinicalTrials.gov 2023 data
02
United States hosts 45% of all trials (201,742 studies), followed by China at 12% (53,798)
03
Europe (EU countries) accounts for 28% of registrations (125,528 studies) as of October 2023
04
Pfizer sponsored 2,150 trials as lead sponsor, most among pharma companies on ClinicalTrials.gov
05
NIH leads 8,500 US government-sponsored trials, 10% of US-based studies
06
India has 7.2% of global trials (32,279 studies), growing 20% annually since 2018
07
Roche/Genentech sponsors 1,800 oncology trials, 1.8% of total therapeutic area studies
08
62% of trials are interventional (277,556 studies), 28% observational (125,528) on ClinicalTrials.gov
09
Japan registers 4.5% of global trials (20,174 studies), with 60% industry-sponsored
10
Germany leads Europe with 28,000 trials (6.3%), pharma hubs like Bayer sponsoring 900
11
AstraZeneca sponsors 1,200 trials, focusing on respiratory and oncology
12
Hospitals/universities sponsor 22% (98,629 studies), US academic centers leading
13
Canada has 3.8% of trials (17,036 studies), 70% multinational collaborations
14
Novartis leads with 1,950 sponsored trials, immunology focus 40%
15
Africa represents 1.2% of trials (5,380 studies), infectious diseases 65%
16
Multinational trials 52% (232,724 studies), average 5 countries per trial
17
Sanofi sponsors 1,100 trials, vaccines 30% (330 studies)
18
Australia/New Zealand 2.1% (9,415 studies), high per capita rate
Interpretation
Geographic and Sponsor Interpretation
While Big Pharma writes 55% of the world's clinical research checks, the U.S. hosts nearly half the stage, and multinational collaboration now defines over half of all trials, the sobering map still shows scientific ambition colored heavily by commercial and geographic privilege, with a patient in Africa being sixty times less likely to be in a trial than one in America.
02 · Category
Phase and Design21 stats
01
Globally, 42% of trials registered in 2022 were Phase 1, compared to 25% Phase 2 and 18% Phase 3
02
Basket trials, a type of master protocol design, increased to 1,200 registrations by 2023, up 300% since 2015
03
Randomized controlled trials (RCTs) account for 65% of interventional Phase 3 studies on ClinicalTrials.gov, totaling around 29,250 studies
04
Umbrella trials number 850 on ClinicalTrials.gov as of 2023, focusing on multiple therapies across biomarkers
05
Platform trials have grown to 450 registered studies by 2023, allowing simultaneous evaluation of multiple interventions
06
Single-arm Phase 2 trials represent 35% of oncology Phase 2 studies, numbering 12,000 across all areas
07
Trials with blinded design (double-blind) comprise 52% of Phase 3 interventional studies, about 23,400 trials
08
Crossover design trials total 2,150 on ClinicalTrials.gov, primarily in Phase 2 for chronic conditions
09
Non-inferiority trials make up 22% of Phase 3 RCTs, equating to roughly 9,900 studies registered
10
Dose-escalation Phase 1 trials number 15,200, representing 72% of all Phase 1 oncology studies
11
Average sample size for Phase 3 trials is 1,250 participants, based on 45,000 registered Phase 3 studies
12
IRB approval delays average 45 days for Phase 1 trials in US, per 1,000 submissions
13
88% of Phase 3 protocols amended at least once, average 2.1 amendments per trial
14
Seamless Phase 2/3 designs used in 15% of adaptive trials (2,625 studies)
15
Biomarker-stratified designs in 28% of oncology Phase 2 trials (10,000+)
16
Placebo-controlled trials 40% of Phase 3 CNS studies (4,000 trials)
17
Enrichment designs applied in 35% of rare disease Phase 2 trials (6,374 studies)
18
55% of Phase 1 trials are first-in-human (FIH), totaling 16,500 studies
19
Parallel-group design dominates 72% of Phase 3 RCTs (33,600 trials)
20
Factorial designs rare at 1.2% of trials (5,380 studies), mostly Phase 2
21
Historical control designs in 8% of oncology single-arm trials (9,600)
Interpretation
Phase and Design Interpretation
It seems science has embraced multitasking, with basket, umbrella, and platform trials now in vogue, yet the heart of evidence remains the humble randomized controlled trial, which—despite being as popular as ever—still takes over a year, several amendments, and a small village of participants to tell us if a new drug is any good.
03 · Category
Results and Impact21 stats
01
Only 45% of trials registered before 2005 have published results, per 2022 analysis of 100,000 studies
02
Phase 3 trials have 75% completion rate within estimated timelines, based on 20,000 reviewed studies
03
82% of oncology Phase 3 trials report primary endpoint success, from 5,000 completed studies analyzed
04
Overall trial completion rate is 68%, with 304,255 completed out of 448,316 total on ClinicalTrials.gov
05
Publication rate for completed trials is 52%, with 150,000+ publications linked to ClinicalTrials.gov studies
06
Adverse event reporting occurs in 92% of Phase 3 trials, averaging 15 serious events per 1,000 participants
07
Positive primary outcome in 70% of industry-sponsored vs 50% academia-sponsored trials, per meta-analysis of 2,000 studies
08
Recruitment success rate is 85% for Phase 1/2, dropping to 65% for Phase 3 trials globally
09
28% of trials are terminated early, primarily due to efficacy (12%) or safety (8%) issues, from 40,000 cases
10
Mean time to primary completion for Phase 3 trials is 3.2 years, based on 10,000 recent studies
11
As of 2022, FDA approved 53 new drugs from 103 Phase 3 trials submitted, a 51% success rate
12
EMA approved 45 new drugs in 2022 from 92 submissions, 49% success post-Phase 3
13
65% of trials post results on ClinicalTrials.gov within 12 months of completion, per 50,000 studies
14
Hazard ratio <0.8 (significant benefit) in 60% of successful oncology Phase 3 trials
15
40% attrition from Phase 2 to Phase 3, based on 3,000 drug candidates tracked
16
Overall drug development success rate 9.6% from Phase 1 to approval, per 2016-2021 analysis
17
78% of vaccine Phase 3 trials meet immunogenicity endpoints, from 200 COVID/non-COVID
18
Median OS improvement 4.2 months in approved immuno-oncology Phase 3 trials
19
55% of rare disease trials (10,000 studies) fail due to recruitment issues
20
Cost per Phase 3 trial averages $19 million USD, from IQVIA analysis of 200 trials
21
92% of published trial results match registry primary outcomes, reduced bias per CONSORT
Interpretation
Results and Impact Interpretation
While the clinical trial system shows promising efficiency in late-phase completion and endpoint success, this progress is frustratingly undercut by persistently low publication rates and high attrition, suggesting we're building a sleek, evidence-based medical future at one-third the expected speed of scientific transparency.
More related reading
04 · Category
Therapeutic Focus19 stats
01
Oncology trials dominate with 22.4% of total registrations (100,000+ studies), followed by neurology at 10.2%
02
Cardiovascular disease trials total 38,500 studies on ClinicalTrials.gov, accounting for 8.6% of interventional trials
03
Infectious diseases, excluding COVID-19, have 25,000 trials, 5.6% of total, with vaccines comprising 40%
04
Mental health disorders trials number 22,000, 4.9% of all studies, led by depression with 8,500 trials
05
Diabetes trials total 18,200, focusing on Type 2 with 12,000 studies, 4.1% overall share
06
Immunology trials, including autoimmune, reach 28,000 studies, 6.3% of registrations as of 2023
07
Respiratory diseases trials number 15,500, with asthma and COPD leading at 7,200 combined
08
Gastroenterology trials total 14,000 studies, 3.1%, dominated by IBS and IBD with 5,500
09
Musculoskeletal trials, including arthritis, have 12,800 studies, 2.9% of total ClinicalTrials.gov entries
10
Endocrine disorders trials total 11,500 (2.6%), led by thyroid with 3,200 studies
11
Dermatology trials number 10,200 (2.3%), psoriasis leading with 4,100 trials
12
Ophthalmology trials 9,800 (2.2%), AMD and glaucoma at 3,500 combined
13
Hematology trials 16,000 (3.6%), sickle cell 2,800 studies
14
Nephrology trials 8,500 (1.9%), CKD leading with 4,200 trials
15
Healthy volunteer trials 25,000 (5.6%), mostly Phase 1 pharmacokinetics
16
Device trials 12,000 interventional (2.7%), cardiology devices 5,000
17
Behavioral interventions trials 18,000 (4.0%), smoking cessation 3,500
18
Genetics trials 7,200 (1.6%), gene therapy 1,800 studies
19
Pregnancy trials only 1,200 (0.3%), due to ethical constraints
Interpretation
Therapeutic Focus Interpretation
In the grand, grim race against human suffering, cancer sets the brutal pace, commanding nearly a quarter of our research battalions, while our collective medical efforts—from heart to mind, from infection to inheritance—form a telling map of which afflictions we fight hardest and, in some sobering cases, which battles we’ve only just begun to muster for.
05 · Category
Trial Volume and Growth20 stats
01
As of October 2023, there are 448,316 clinical studies registered on ClinicalTrials.gov, spanning 220 countries and targeting over 3,900 conditions
02
From 2000 to 2023, annual registrations on ClinicalTrials.gov increased from 3,000 to over 50,000 per year, representing a 16-fold growth
03
In 2022, 66,000 new interventional trials were registered globally on ClinicalTrials.gov, with 40% from industry sponsors
04
The oncology therapeutic area accounts for 22% of all registered trials on ClinicalTrials.gov as of 2023, totaling approximately 98,629 studies
05
COVID-19 related trials peaked at 4,460 registered studies in 2020, comprising 15% of all new registrations that year
06
Phase 3 trials represent 18% of all interventional studies on ClinicalTrials.gov, numbering about 45,000 as of 2023
07
Between 2018 and 2022, the number of trials using adaptive design increased by 250%, from 500 to 1,750 registered studies
08
Observational studies make up 28% of ClinicalTrials.gov registrations, totaling 125,528 studies as of October 2023
09
Pediatric trials constitute only 12% of all trials on ClinicalTrials.gov, with 53,798 studies specifically targeting children under 18
10
Rare disease trials number 18,214 on ClinicalTrials.gov, representing 4.1% of total studies as of 2023
11
Serious adverse events occur in 1 in 50 Phase 1 participants (2%) in oncology trials, from 5,000 studies
12
Grade 3+ adverse events reported in 45% of Phase 2 immunotherapy trials, averaging 25% incidence rate
13
Dose-limiting toxicities halt 18% of Phase 1 trials early, per analysis of 1,200 escalation studies
14
Mortality as adverse event in 0.5% of all interventional trials (2,237 cases reported)
15
75% of vaccine trials report mild local reactions (injection site pain) in >50% participants
16
All-cause discontinuation due to AEs is 8% in Phase 3 cardiovascular trials, from 2,000 studies
17
Hypersensitivity reactions occur in 3.2% of monoclonal antibody trials, totaling 1,500 events
18
Liver enzyme elevations (ALT >3x ULN) in 12% of Phase 2 trials for NASH
19
Neurotoxicity in 22% of CAR-T cell therapy trials, Grade 3+ in 10%
20
95% of trials adhere to GCP standards per FDA inspections of 500 sites annually
Interpretation
Trial Volume and Growth Interpretation
The sobering reality behind these staggering numbers is that while the global clinical research engine is running at unprecedented scale and speed—churning out thousands of trials for everything from cancer to COVID—it remains a high-stakes gamble where progress is often measured in percentages of participants who suffer significant harm.
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
Gabrielle Fontaine. (2026, February 13). Clinical Study Statistics. Gitnux. https://gitnux.org/clinical-study-statistics
MLA
Gabrielle Fontaine. "Clinical Study Statistics." Gitnux, 13 Feb 2026, https://gitnux.org/clinical-study-statistics.
Chicago
Gabrielle Fontaine. 2026. "Clinical Study Statistics." Gitnux. https://gitnux.org/clinical-study-statistics.
Sources & references
8 datasets cited across this report · attribution is report-level