DrugEvidence

Drugs / Aspirin

Aspirin

Drug

Aspirin (acetylsalicylic acid) is a nonsteroidal anti-inflammatory drug used for pain, fever, inflammation, and antithrombotic prevention. It is widely available as an over-the-counter medicine in many jurisdictions and remains one of the most used medicines globally. It also has long-term preventive use in selected cardiovascular patients.

Trials
1130
Recruiting
112
Completed
582
With results
208

Last revised

Pipeline

Phase by status

PhaseRecruitingNot yetBy invitationActiveCompletedTerminatedWithdrawnSuspendedUnknownNo longer availableTotal
Early Phase 1 411621415 43
Phase 1 31703214 84
Phase 1/2 22813 16
Phase 2 112789186116 150
Phase 2/3 23116120 43
Phase 3 3414610425933 225
Phase 4 40172616622775 335
Not applicable 11577512844 162
Unknown 7113323241 72

Trials started per year

2021
14
2022
48
2023
48
2024
45
2025
41
2026
36
2027
4

Conditions studied, by phase

ConditionEarly Phase 1Phase 1Phase 1/2Phase 2Phase 2/3Phase 3Phase 4Not applicableUnknownTotal
Coronary Artery Disease 145115641414 118
Stroke 337302396 81
Ischemic Stroke 55102320411 78
Cardiovascular Diseases 1417122494 62
Pre-Eclampsia 32511317112 54
Acute Coronary Syndrome 4362633 45
Myocardial Infarction 161121814 43
Thrombosis 13571665 43
Peripheral Arterial Disease 1261376 35
Atrial Fibrillation 2101632 33

Most active sponsors

#SponsorTrialsPhase 3
1Bayer3713
2AstraZeneca132
3Assiut University122
4Xijing Hospital124
5Beijing Tiantan Hospital118
6Bristol-Myers Squibb111
7Assistance Publique - Hôpitaux de Paris106
8Boehringer Ingelheim104
9National Cancer Institute (NCI)100
10Peking Union Medical College Hospital91

Most studied interventions

#InterventionTrials
1Aspirin1130
2Clopidogrel289
3Ticagrelor101
4Rivaroxaban69
5Warfarin37
6Cilostazol35
7Atorvastatin32
8Prasugrel Hydrochloride26
9apixaban25
10Enoxaparin22

Evidence

Results reported
35.7%208 of 582 completed
Published
17.9%104 of 582 completed
Primary endpoint met
43.9%58 of 132 analyses
Median months to report
16

Documents disclosed

Protocol available
107
Statistical analysis plan
106
PubMed citations
552

Trial profile

Median enrollment
126
Median duration
34.3months
Countries
96
Study sites
11893

Who is enrolled

Adults
1113
Children
76
Older adults
948
Healthy volunteers
252

Median enrollment by phase

Early Phase 1
47
Phase 1
40
Phase 1/2
49
Phase 2
62
Phase 2/3
100
Phase 3
468
Phase 4
194
Not applicable
100
Unknown
402

Where trials run

United States
340
China
178
Canada
94
South Korea
86
United Kingdom
78
France
61
Italy
58
Germany
49
Spain
47
Denmark
43

Busiest cities

#CityCountryTrials
1New YorkUnited States68
2BeijingChina65
3SeoulSouth Korea60
4BostonUnited States55
5HoustonUnited States51
6PhiladelphiaUnited States48
7BaltimoreUnited States42
8ChicagoUnited States41
9ParisFrance41
10ShanghaiChina41

Terminations

Terminated
88
Withdrawn
35
Suspended
3
Stopped for recruitment
3.1%35 of 1130 trials

Stated reasons

Other / unclear
55
Recruitment
35
Funding
16
COVID-19
6
Business decision
4
Lack of efficacy
4
Regulatory
3
Safety
3

Reasons are grouped from the sponsor's own wording with a rule-based classifier; the original text is shown below.

Recently stopped

TrialStatusStated reasonStopped
NCT03186456 Suspended Suspended Others 2027-12-31
NCT06290765 Withdrawn Withdrawn In alignment with company strategic direction. 2027-06-30
NCT05080946 Suspended Suspended Study drug is expiring. Will reopen when new drug is received. 2026-12-31
NCT04308551 Withdrawn Withdrawn shortage of funds 2026-12-30
NCT03729401 Terminated Terminated Testing supplies unavailable. 2026-02-26
NCT05104229 Withdrawn Withdrawn Limited Resources 2026-01-01
NCT03796156 Terminated Terminated Planned recruitment total was not achievable within the funded timeframe 2025-09-23
NCT04188119 Withdrawn Withdrawn Unable to open 2025-05-31
NCT06280976 Withdrawn Withdrawn study withdrawn, no participants enrolled, changes in the study design planned 2025-01-01
NCT04217447 Terminated Terminated The sponsor's decision to stop the study follows the DSMB's recommendations (end of enrolment and experimental treatment, post-treatment/end-of-study visit within 3 months of stopping treatment), regarding the benefit-risk balance. 2024-10-28

Trial records

Individual study records live on ClinicalTrials.gov. A sample of the trials counted above:

Search all Aspirin trials on ClinicalTrials.gov →