Most Studied Conditions

Medical conditions with the most U.S. clinical trials, ranked by total trial count drawn from ClinicalTrials.gov. According to ClinicalTrials.gov, the NIH registry maintained by the National Library of Medicine contains more than 500,000 studies in more than 220 countries. The 2007 FDAAA requires registration for most FDA-regulated studies. See our methodology for refresh cadence.

The number of clinical trials for a condition reflects research interest, unmet medical need, and commercial opportunity. Cancer-related conditions dominate clinical trial activity due to the large patient population, high unmet need, and the complexity of treatment (requiring many different therapeutic approaches to be tested). Cardiovascular, neurological, and autoimmune conditions also attract significant trial activity. The conditions with the most recruiting trials represent areas of active enrollment where patients may have opportunities to participate.

Condition Total trials
  1. 1 Breast Cancer 423 recruiting 1,251
  2. 2 Healthy 225 recruiting 1,096
  3. 3 Obesity 306 recruiting 1,057
  4. 4 Prostate Cancer 275 recruiting 749
  5. 5 Depression 245 recruiting 687
  6. 6 Cancer 279 recruiting 621
  7. 7 HIV Infections 56 recruiting 615
  8. 8 Hypertension 152 recruiting 472
  9. 9 Stroke 218 recruiting 456
  10. 10 Non-Small Cell Lung Cancer 206 recruiting 455
  11. 11 Multiple Myeloma 167 recruiting 441
  12. 12 Lung Cancer 146 recruiting 430
  13. 13 Heart Failure 164 recruiting 399
  14. 14 Colorectal Cancer 162 recruiting 394
  15. 15 Asthma 70 recruiting 378
  16. 16 Pain 106 recruiting 377
  17. 17 Anxiety 148 recruiting 367
  18. 18 Diabetes Mellitus, Type 2 63 recruiting 351
  19. 19 Diabetes 86 recruiting 342
  20. 20 Ovarian Cancer 147 recruiting 338
  21. 21 Lymphoma 88 recruiting 330
  22. 22 Type 2 Diabetes 120 recruiting 328
  23. 23 Schizophrenia 76 recruiting 318
  24. 24 Multiple Sclerosis 120 recruiting 317
  25. 25 Alzheimer Disease 155 recruiting 312
  26. 26 Acute Myeloid Leukemia 159 recruiting 307
  27. 27 HIV 109 recruiting 304
  28. 28 Cardiovascular Diseases 134 recruiting 304
  29. 29 Chronic Pain 139 recruiting 302
  30. 30 COVID-19 68 recruiting 299
  31. 31 Parkinson Disease 135 recruiting 298
  32. 32 Healthy Volunteers 79 recruiting 284
  33. 33 Major Depressive Disorder 109 recruiting 283
  34. 34 Pancreatic Cancer 101 recruiting 283
  35. 35 Leukemia 51 recruiting 274
  36. 36 Melanoma 89 recruiting 269
  37. 37 Post Traumatic Stress Disorder 110 recruiting 265
  38. 38 Aging 126 recruiting 263
  39. 39 Head and Neck Cancer 89 recruiting 260
  40. 40 Opioid Use Disorder 156 recruiting 258
  41. 41 Autism Spectrum Disorder 112 recruiting 225
  42. 42 Coronary Artery Disease 57 recruiting 220
  43. 43 Sickle Cell Disease 95 recruiting 214
  44. 44 Diabetes Mellitus 49 recruiting 210
  45. 45 Mild Cognitive Impairment 100 recruiting 206
  46. 46 Atrial Fibrillation 60 recruiting 204
  47. 47 Spinal Cord Injuries 108 recruiting 203
  48. 48 Dementia 79 recruiting 202
  49. 49 Glioblastoma 78 recruiting 200
  50. 50 Type 1 Diabetes 79 recruiting 199

The bar to make this list

How the top 50's own trial counts spread out

the top 50, bucketed by value

Each bar is a band; taller bars hold more conditions. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source ClinicalTrials.gov

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