ClinicalTrials.gov currently lists 134,926 studies with locations in all 50 states and in 181 countries.

Locations of Recruiting Studies

Recruiting Study Location Count Pie Chart
    Non-U.S. Only (49%)
    U.S. Only (45%)
    Both U.S. & Non-U.S. (7%)
Total N = 29,181 studies
Data as of October 30, 2012