How many clinical trials start each year?
About 30,800 clinical trials registered on ClinicalTrials.gov started in 2025, up from about 11,900 in 2008 and 1,900 in 2000, the registry's first year. Early years count fewer trials because registering wasn't required until medical journals asked for it in 2005 and a U.S. law did in 2007; late registrations still add a few to recent years. ClinicalTrials.gov lists trials from around the world, not only the U.S.
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Measure: Clinical trials started. Written from the data below.
- The latest figure, for 2025, is 30,920.
- That is 16 times the 2000 figure, 1,876.
- It is the highest in the data, which go back to 2000.
- The lowest was 1,876 in 2000.
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- Data as of
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Citation
Chartly. “How many clinical trials start each year?” Chart. Data: ClinicalTrials.gov (U.S. National Library of Medicine), counted with its API v2, https://clinicaltrials.gov/data-api/api (data as of October 14, 2026). https://chart.ly/charts/clinical-trials-started-per-year (accessed October 15, 2026).
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The data
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| Year the trial started | Clinical trials started |
|---|---|
| 2000 | 1,876 |
| 2001 | 2,407 |
| 2002 | 3,497 |
| 2003 | 4,770 |
| 2004 | 6,319 |
| 2005 | 7,729 |
| 2006 | 9,300 |
| 2007 | 10,422 |
| 2008 | 11,900 |
| 2009 | 12,848 |
| 2010 | 13,420 |
| 2011 | 14,217 |
| 2012 | 15,027 |
| 2013 | 15,896 |
| 2014 | 17,600 |
| 2015 | 18,947 |
| 2016 | 20,370 |
| 2017 | 21,265 |
| 2018 | 22,870 |
| 2019 | 23,828 |
| 2020 | 23,595 |
| 2021 | 28,330 |
| 2022 | 28,111 |
| 2023 | 29,473 |
| 2024 | 30,651 |
| 2025 | 30,920 |
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