Clinical Trials by State

U.S. states ranked by total clinical trial count, drawn from ClinicalTrials.gov, the U.S. National Institutes of Health public registry maintained by the U.S. National Library of Medicine. According to ClinicalTrials.gov, the registry catalogs more than 500,000 clinical studies since 1997. See our methodology for refresh cadence.

The number of clinical trials hosted in a state reflects the concentration of academic medical centers, research hospitals, and pharmaceutical activity. States with large populations and major research universities tend to host the most trials, offering local patients more opportunities to participate in active studies.

#StateTotal Trials†Recruiting
1 California 16,646 5,482
2 Florida 10,986 3,625
3 New York 10,554 3,675
4 Texas 9,951 3,731
5 Massachusetts 7,667 2,710
6 Pennsylvania 6,946 2,373
7 Illinois 6,854 2,290
8 Ohio 6,514 2,298
9 Maryland 6,441 2,178
10 North Carolina 5,625 1,847
11 Arizona 5,607 1,688
12 Colorado 5,273 1,650
13 Georgia 5,195 1,657
14 Michigan 4,790 1,648
15 Minnesota 4,506 1,633
16 Alabama 4,168 1,209
17 Missouri 4,116 1,339
18 Connecticut 3,531 1,136
19 Tennessee 3,520 1,176
20 New Jersey 3,402 1,145
21 Indiana 3,113 903
22 Washington 2,795 913
23 Virginia 2,598 1,028
24 Arkansas 2,376 676
25 District of Columbia 2,316 727
26 Kentucky 2,183 700
27 Kansas 2,080 606
28 Oregon 1,999 679
29 Louisiana 1,936 534
30 Wisconsin 1,760 659
31 Utah 1,734 654
32 South Carolina 1,706 591
33 Iowa 1,544 508
34 Nebraska 1,301 382
35 Oklahoma 1,061 364
36 Nevada 900 240
37 Rhode Island 753 258
38 Delaware 652 218
39 Idaho 633 167
40 New Mexico 579 168
41 Mississippi 500 137
42 Alaska 485 123
43 New Hampshire 471 155
44 Hawaii 437 112
45 Maine 315 72
46 West Virginia 277 101
47 South Dakota 273 85
48 Montana 250 56
49 North Dakota 235 44
50 Vermont 191 60
51 Wyoming 17 6
52 Puerto Rico 14 8

† Counts include only the 60,823 of 175,638 indexed trials (35%) that have a listed U.S. site. Coverage is uneven by status: 92% of recruiting and active trials, 24% of completed trials, and 0 of the 23,032 terminated or not-yet-recruiting trials. Completed, terminated and upcoming studies are therefore under-counted in every state, so read the recruiting figures as the most complete.

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