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ClinicalTrials.gov 2 recruiting now full pipeline small index

Phelan-McDermid Syndrome: full-pipeline trial registry

2 of 5 indexed Phelan-McDermid Syndrome trials are currently recruiting.

Corpus placement: #3,391 of 28,707 conditions by registered trial count.

5 US clinical trials · 2 currently recruiting · #3,391 of 28,707 conditions by registered trial count

Phelan-McDermid Syndrome: 5 US clinical trials tracked, 2 recruiting.

Phelan-McDermid Syndrome is the subject of 5 registered US clinical trials on ClinicalTrials.gov, 2 of them currently open to new participants. 1 are in Phase 3-4 (later-stage) and 1 in Phase 1-2 (earlier-stage). The most active sponsor is Boston Children's Hospital, running 2 of these trials.

Enrollment posture brief

Registry condition phelan-mcdermid-syndrome

OPEN 2 | RECR 40% | LATE 1 | EARLY 1 | RANK #3391 | SPON 2

Nearest open-share peer: Achondroplasia (40% recruiting · 10 trials)

Ablation80%ACL Reconstruction80%Abuse, Drug60%Acceptability60%Phelan-McDermid Syndrome (th…40%
Open-enrollment share among volume-matched conditions near Phelan-McDermid Syndrome

Phelan-McDermid Syndrome lists 2 open slots (40% of 5 indexed trials). Peers are matched on registered volume, not therapeutic-area browse lists. How peer matching works →

Key findings

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

    2 of 5 indexed trials (40%) 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 Phelan-McDermid Syndrome research.

    Boston Children's Hospital accounts for 2 of 5 trials (40%). 4 distinct sponsors appear on at least one study for this condition label.

  3. Most Phelan-McDermid Syndrome trials plan to enrol fewer than 100 people.

    Median target enrolment is 51 among the 5 trials that report a genuine target (sentinel values excluded). 3 of those (60%) plan for fewer than 100 participants.

  4. Phelan-McDermid Syndrome research leans observational.

    2 interventional and 3 observational studies make up this index (40% interventional). Study type is sponsor-reported on ClinicalTrials.gov.

Phase 11Phase 31

Phase Distribution

PhaseTrial count
Phase 1 1
Phase 3 1

Named interventions

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

NNZ-2591 Drug
1 trials
JAG201 Genetic
1 trials
No Intervention Other
1 trials
Placebo Drug
1 trials

US sites by state

Facility locations filed on Phelan-McDermid Syndrome trials. A trial with sites in several states counts in each.

New York 3 trials
Maryland 3 trials
Massachusetts 3 trials
Illinois 3 trials
California 3 trials
Texas 1 trials
Arkansas 1 trials

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

What to do with this Phelan-McDermid Syndrome page

5 registered trials, 2 currently recruiting, is a starting point for a conversation, not a diagnosis or a recommendation.

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 Phelan-McDermid Syndrome condition card totals 5 registered trials; most-linked intervention NNZ-2591; top US site state New York. See our editorial standards & corrections policy, the methodology behind these numbers, the data changelog, or report a data error.