Data
Number of clinical trials
What you should know about this indicator
- This data comes from the ClinicalTrials.gov database. It only includes interventional or observational clinical trials that are marked as "completed" and have a valid "completion date". Expanded access studies, which provide access to investigational drugs or devices for patients with serious conditions, are not included in this data.
- Country location is determined by the country with the most locations listed in the trial. If multiple countries have the same number of locations, the first one listed is used.
- The year is the year of the trial's completion date. This is first entered (as a planned completion data) when the trial is first registered, and then updated when the trial is completed.
Number of clinical trials
Annual number of completed clinical trials registered in the ClinicalTrials.gov database for each country. Registration in the ClinicalTrials database is mandatory for trials in the United States, but voluntary for other countries.
Source
ClinicalTrials.gov (2025) – with major processing by Our World in Data
Last updated
July 28, 2025
Next expected update
July 2026
Date range
1918–2031
Unit
trials
What you should know about this indicator
- This data comes from the ClinicalTrials.gov database. It only includes interventional or observational clinical trials that are marked as "completed" and have a valid "completion date". Expanded access studies, which provide access to investigational drugs or devices for patients with serious conditions, are not included in this data.
- Country location is determined by the country with the most locations listed in the trial. If multiple countries have the same number of locations, the first one listed is used.
- The year is the year of the trial's completion date. This is first entered (as a planned completion data) when the trial is first registered, and then updated when the trial is completed.
Number of clinical trials
Annual number of completed clinical trials registered in the ClinicalTrials.gov database for each country. Registration in the ClinicalTrials database is mandatory for trials in the United States, but voluntary for other countries.
Source
ClinicalTrials.gov (2025) – with major processing by Our World in Data
Last updated
July 28, 2025
Next expected update
July 2026
Date range
1918–2031
Unit
trials
Sources and processing
This data is based on the following sources
How we process data at Our World in Data
All data and visualizations on Our World in Data rely on data sourced from one or several original data providers. Preparing this original data involves several processing steps. Depending on the data, this can include standardizing country names and world region definitions, converting units, calculating derived indicators such as per capita measures, as well as adding or adapting metadata such as the name or the description given to an indicator.
At the link below you can find a detailed description of the structure of our data pipeline, including links to all the code used to prepare data across Our World in Data.
Notes on our processing step for this indicator
- If multiple locations are listed, the country with the most locations listed is used. If multiple countries have the same number of locations, the first one listed is used.
- If a trial has no locations listed or the country is not specified, the location is set to "Location not specified".
Reuse this work
- All data produced by third-party providers and made available by Our World in Data are subject to the license terms from the original providers. Our work would not be possible without the data providers we rely on, so we ask you to always cite them appropriately (see below). This is crucial to allow data providers to continue doing their work, enhancing, maintaining and updating valuable data.
- All data, visualizations, and code produced by Our World in Data are completely open access under the Creative Commons BY license. You have the permission to use, distribute, and reproduce these in any medium, provided the source and authors are credited.
Citations
How to cite this page
To cite this page overall, including any descriptions, FAQs or explanations of the data authored by Our World in Data, please use the following citation:
“Data Page: Number of clinical trials”. Our World in Data (2025). Data adapted from ClinicalTrials.gov. Retrieved from https://archive.ourworldindata.org/20250918-121032/grapher/number-of-clinical-trials.html [online resource] (archived on September 18, 2025).How to cite this data
In-line citationIf you have limited space (e.g. in data visualizations), you can use this abbreviated in-line citation:
ClinicalTrials.gov (2025) – with major processing by Our World in DataFull citation
ClinicalTrials.gov (2025) – with major processing by Our World in Data. “Number of clinical trials” [dataset]. ClinicalTrials.gov, “Clinical Trials (ClinicalTrials.gov)” [original data]. Retrieved December 5, 2025 from https://archive.ourworldindata.org/20250918-121032/grapher/number-of-clinical-trials.html (archived on September 18, 2025).