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ClinicalTrials.gov 1,650 recruiting now below national open share #12 of 52 states

Colorado: below-average open trial sites

1,650 of 5,273 in-state trials are recruiting (31%); below the 37% national average by 6 percentage points.

According to ClinicalTrials.gov-derived indexes, Colorado sits in the upper quartile of US states by in-state trial count (#12 of 52 states by registered in-state trial count).

Colorado: 5,273 US clinical trials with in-state sites, 1,650 recruiting.

Colorado has 5,273 registered US clinical trials with a study site in-state, 1,650 of them currently recruiting (below the 37% national average by 6 percentage points). 1,536 of these trials are in Phase 3 (late-stage) and 1,205 in Phase 2. The most frequently studied condition in Colorado is HIV Infections, with 107 linked trials.

Upper-quartile research density

Colorado sits in the upper quartile by in-state trial count. Open share is below the 37% national average by 6 percentage points - denser than most states, still short of the top-decile research hubs.

Below-average open enrollment

Colorado still shows 1,650 recruiting of 5,273 in-state trials (31% open), but below the 37% national average by 6 percentage points, so archived statuses weigh heavier than the national baseline.

31%
open (below national share)
1,650
still recruiting despite cool share
1,205
Phase 2 rows in this footprint
107
top: HIV Infections

Recruiting share is below the 37% national average by 6 percentage points. Counts include every study with at least one recorded site in the state. Registry reference only, not medical advice.

Colorado vs all states by indexed in-state trial count

Where this state's ClinicalTrials.gov site count sits among every state with at least one listed trial (coverage density, not care quality)

5,273 Top 23% more indexed trials than 77% of 52 states

States, banded by indexed in-state trial count

Each bar is a band; taller bars hold more states. 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 · 2026-08-08

Key findings

What ClinicalTrials.gov does not surface for Colorado on its own pages , computed from the registry mirror as of 2026-08-08. Each line carries its own denominator so it can be quoted as it stands.

  1. Colorado open-enrollment share sits below the national baseline.

    1,650 of 5,273 in-state trials (31.3%) are recruiting, against 37% nationally (-5.7 percentage points). Counts include every study with at least one recorded site in the state.

  2. Colorado trial sites spread across 8 city hubs.

    Aurora lists 2,514 of 5,273 in-state trials (47.7%) across 710 named facilities. Cities need five or more listed trials to appear here; locations are as filed by sponsors.

  3. HIV Infections is the most-studied condition in Colorado.

    107 of 5,273 in-state trials (2%) list HIV Infections. That is a local concentration figure, not a national disease ranking.

  4. One sponsor accounts for a large share of Colorado trials.

    University of Colorado, Denver appears on 525 of 5,273 in-state trials (10%). Sponsor identity is as filed on ClinicalTrials.gov.

  5. 2,339 Colorado trials carry a completed status.

    2,339 of 5,273 (44.4%) are completed. The open share above is the remainder that still lists recruiting.

Phase 31,536Phase 21,205NA884Phase 1726Phase 4215Early Phase 122
Treemap Treemap of 15 categories, sized proportional to value. HIV Infections 107 Breast Cancer 99 Asthma 81 Non-Small Cell L… 81 Obesity 57 Multiple My… 56 Cystic Fibrosis 55 Prostate Cancer 55 Colorectal C… 47 Multiple Scl… 44 Diabetes Mell… 41 Lung Cancer 39 Heart Failure 38 Ovarian Cancer 38 Type 1 Diabetes 37

By Status

StatusTrial count
Completed 2,339
Recruiting 1,650
Active 1,284

By Phase

PhaseTrial count
Phase 3 1,536
Phase 2 1,205
NA 884
Phase 1 726
Phase 4 215
Early Phase 1 22

Where trials run in Colorado

Aurora carries 2,514 of Colorado's 5,273 indexed trials (48%) across 710 named sites, ahead of Denver at 1,712. 8 cities clear five listed trials, together naming 2,068 distinct sites.

City Trials Listed sites
Aurora 2,514 710
Denver 1,712 660
Colorado Springs 512 256
Englewood 250 123
Fort Collins 188 99
Boulder 182 77
Lakewood 162 78
Littleton 132 65

Distinct trials and named sites per city, as filed with ClinicalTrials.gov; cities under five trials omitted. Vintage 2026-08-08.

Volume high

Colorado indexes 5,273 in-state trials (p78 by registry volume among 52 states with sites).

Colorado: in-state trial volume sits in the high tercile

Sites spread across 8 cities with five or more listed trials, led by Aurora (2,514, 48% of the state total) and Denver (1,712), together naming 2,068 distinct research locations.

Phase mix: 1,536 Phase 3 vs 1,205 Phase 2 (balanced across stages).

Top condition: HIV Infections (107 trials); top sponsor University of Colorado, Denver (525).

high-volume · mid-open figures (5,273 trials · 31% open) describe registry geography under the volume high read, not clinic capacity or protocol fit. Confirm status on ClinicalTrials.gov before acting.

States near Colorado on in-state trial volume

Cross-state peers under the volume high read (high-volume · mid-open), not the same-state browse list.

Similar high-volume hubs (± open share)

Similar mid-open peers (± trial volume)

Source: ClinicalTrials.gov, the US trial registry maintained by the National Library of Medicine, part of the NIH. Colorado series (high-volume · mid-open · volume high) retrieved and formatted by PlainTrial, see methodology.