Clinical trials

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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Source and date

Data as of
Published

The data

Year the trial started Clinical trials started
2000 1,876
2001 2,407
2002 3,497
2003 4,770
2004 6,318
2005 7,729
2006 9,302
2007 10,423
2008 11,898
2009 12,848
2010 13,420
2011 14,217
2012 15,027
2013 15,897
2014 17,599
2015 18,943
2016 20,366
2017 21,262
2018 22,870
2019 23,830
2020 23,586
2021 28,307
2022 28,090
2023 29,421
2024 30,544
2025 30,795