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ClinicalTrials.gov enrollment closed early-phase tilt small index

Smallpox: early-phase trial registry

A small indexed set (8 trials) with no open enrollment listed right now.

Corpus placement: #2,176 of 28,707 conditions by registered trial count.

8 US clinical trials · none currently recruiting · #2,176 of 28,707 conditions by registered trial count

Smallpox: 8 US clinical trials tracked, none currently recruiting.

Smallpox is the subject of 8 registered US clinical trials on ClinicalTrials.gov, none currently recruiting. 0 are in Phase 3-4 (later-stage) and 5 in Phase 1-2 (earlier-stage). The most active sponsor is Emergent BioSolutions, running 3 of these trials.

Enrollment posture brief

Registry condition smallpox

OPEN 0 | RECR 0% | LATE 0 | EARLY 5 | RANK #2176 | SPON 3

Nearest open-share peer: Accelerated Phase Chronic Myelogenous Leukemia (0% recruiting · 12 trials)

Activity, Motor75%Achalasia50%Abdominal Cancer25%Acne Scars - Mixed Atrophic 25%Smallpox (this)0%
Open-enrollment share among volume-matched conditions near Smallpox

Smallpox has no open enrollment in this registry pull (8 archived studies). Peers show how other volume-matched labels compare on open share. How peer matching works →

Key findings

What ClinicalTrials.gov does not surface for Smallpox 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. Smallpox is recruiting below its size-band peers.

    0 of 8 indexed trials (0%) are open to enrollment, against a 46.5% average across 27,806 conditions with fewer than 20 trials. The peer set uses the same ClinicalTrials.gov-derived counts as this page.

  2. One sponsor concentrates Smallpox research.

    Emergent BioSolutions accounts for 3 of 8 trials (37.5%). 4 distinct sponsors appear on at least one study for this condition label.

  3. Typical Smallpox enrolment sits around 523 participants.

    Median target enrolment is 523 among the 8 trials that report a genuine target (sentinel values excluded). 2 of those (25%) plan for fewer than 100 participants.

  4. Smallpox splits between interventional and observational designs.

    5 interventional and 3 observational studies make up this index (62.5% interventional). Study type is sponsor-reported on ClinicalTrials.gov.

Phase 11Phase 24

Phase Distribution

PhaseTrial count
Phase 1 1
Phase 2 4

Named interventions

Most-linked intervention names on Smallpox records (sponsor-reported on ClinicalTrials.gov). Counts are trial links, not unique products.

MVA Smallpox Vaccine Biological
2 trials
Placebo Other
2 trials
Dryvax Biological
1 trials
Live vaccinia virus vaccine Biological
1 trials
ACAM2000® smallpox vaccine Biological
1 trials
IMVAMUNE® Biological
1 trials
Smallpox and Mpox Vaccine Drug
1 trials
Tecovirimat Drug
1 trials

US sites by state

Facility locations filed on Smallpox trials. A trial with sites in several states counts in each.

Texas 4 trials
Missouri 4 trials
Iowa 3 trials
California 3 trials
Ohio 2 trials
Maryland 2 trials
Kentucky 2 trials
Washington 1 trials

Source: ClinicalTrials.gov, National Library of Medicine. Data is informational only.

What to do with this Smallpox page

8 registered trials, 0 currently recruiting, is a starting point for a conversation, not a diagnosis or a recommendation.

  • No Smallpox trials are currently recruiting in this registry; that can change as new trials post, or check the broader research index. Browse research indexes
  • Emergent BioSolutions sponsors the most Smallpox trials on record, review their full trial history before evaluating a specific study. See Emergent BioSolutions's trials
  • Bring the specific trial ID (NCT number) to your own doctor before enrolling, this page is a directory, not medical guidance. Read the trial-finding guide

Trial and recruiting counts reflect ClinicalTrials.gov registry status as of the data vintage above; individual trial eligibility and enrollment status can change.

Every figure on PlainTrial is rendered directly from the ClinicalTrials.gov registry, no number is typed in by an editor. This Smallpox condition card totals 8 registered trials; most-linked intervention MVA Smallpox Vaccine; top US site state Texas. See our editorial standards & corrections policy, the methodology behind these numbers, the data changelog, or report a data error.