Actively Recruiting

Phase 3
Age: 3Years - 12Years
All Genders
ID07281079

A Phase 3 Randomized, Double-blind, Placebo-controlled Study to Investigate the Efficacy and Safety of Orally Administered NNZ-2591 Compared With Placebo in Pediatric Participants With Phelan-McDermid Syndrome

Led by Neuren Pharmaceuticals Limited · Updated on 2026-05-29

160

Participants Needed

7

Research Sites

2 weeks

Total Duration

On this page

AI-Summary

What this Trial Is About

Researchers are evaluating the effectiveness and safety of NNZ-2591 compared to a placebo in children aged 3 to 12 years with Phelan-McDermid Syndrome, a rare genetic condition caused by abnormalities in the SHANK3 gene. This Phase 3, randomized, double-blind, placebo-controlled study includes multiple centers to ensure broad participation and reliable results. After informed consent, participants will enter a 4-week screening period to confirm eligibility and assess baseline symptoms. Those who qualify will be randomly assigned to receive either NNZ-2591 or a matching placebo, both taken orally twice daily, during a 13-week treatment period. Following treatment, there will be a 2-week safety follow-up to monitor participants. During the study, children will undergo various assessments including the Phelan-McDermid Syndrome Assessment of Change and the Vineland Adaptive Behavior Scales to evaluate communication and behavior changes. Caregivers will provide impressions of change, and researchers will monitor safety through clinical evaluations. The total participation time per child is approximately 17 to 19 weeks.

CONDITIONS

Brief Title

A Study of NNZ-2591 in Pediatric Participants With Phelan-McDermid Syndrome

Who Can Participate

Age: 3Years - 12Years
All Genders

Eligibility Criteria

Eligible

You may qualify if you...

  • Male or female pediatric participants with Phelan-McDermid syndrome aged 3 to 12 years at the time of consent
  • Clinical diagnosis of Phelan-McDermid syndrome with a documented SHANK3 genetic abnormality
  • Body weight of at least 10 kilograms at screening
  • PMSA-S overall score of 3 or higher at Screening and Baseline visits
  • Not currently experiencing regression or loss of skills
Not Eligible

You will not qualify if you...

  • Use of exclusionary medications or unstable treatment regimens as specified by the protocol
  • Treatment with more than 3 allowable psychotropic medications
  • Participants with seizures must be controlled on no more than 2 anticonvulsant medications, excluding rescue medications
  • Psychotropic or chronic illness medications not stable for at least 4 weeks before screening or discontinued less than 2 weeks before screening
  • Any seizures in the past 6 months or more than one seizure in the past 12 months (a single febrile seizure without rescue medication in the past 6 months is allowed)
  • Abnormal liver function tests during screening as defined by the protocol
  • Abnormal QT interval on screening ECG as defined by the protocol

AI-Screening

AI-Powered Screening

Complete this quick 3-step screening to check your eligibility

1
2
3
+1

Your Study Journey

Screening

Duration - 4 weeks

Participants are screened for eligibility to participate in the trial.

Assessments for eligibility, baseline characteristics, and symptom severity occur during this period.

Treatment

Duration - 13 weeks

Participants receive either the study drug NNZ-2591 or a matching placebo, administered orally twice daily.

Visits occur throughout the treatment period to monitor efficacy and safety.

Follow-up

Duration - 2 weeks

Participants undergo a safety follow-up period immediately after completing treatment to monitor for any adverse effects.

Visits focus on safety assessments following treatment completion.

Trial Site Locations

Total: 7 locations

1

Neuren PMS-301 Site#111

San Rafael, California, United States, 94903

Actively Recruiting

2

Neuren PMS-301 Site#102

Chicago, Illinois, United States, 60612

Actively Recruiting

3

Neuren PMS-301 Site#109

Chevy Chase, Maryland, United States, 20815

Actively Recruiting

4

Neuren PMS-301 Site#106

Brookline, Massachusetts, United States, 02445

Actively Recruiting

5

Neuren PMS-301 Site#104

Lexington, Massachusetts, United States, 02421

Actively Recruiting

6

Neuren PMS-301 Site#101

New York, New York, United States, 10029

Actively Recruiting

7

Neuren PMS-301 Site#108

Cincinnati, Ohio, United States, 45229

Actively Recruiting

Loading map...

Research Team

M

Medical Information Lead

How is the study designed?

Study Type

INTERVENTIONAL

Masking

QUADRUPLE

Allocation

RANDOMIZED

Model

PARALLEL

Primary Purpose

TREATMENT

Number of Arms

2

Similar Trials

A Phase 3 Open-label Extension Study to Investigate the Long...

Phelan-McDermid Syndrome

Actively Recruiting

1 location

JAG201 Gene Therapy Phase 1/2 Study via Intracerebroventricu...

SHANK3 Haploinsufficiency

Actively Recruiting

3 locations

An Open-label, Single Arm, Dose-Escalation Study Evaluating ...

Phelan-McDermid Syndrome

Actively Recruiting

1 location

Frequently Asked Questions

Have more questions? Get in touch with our team for quick support

Not the Right Trial for You?

Explore thousands of other clinical trials that might be a better match.
Sign up to get personalized trial recommendations delivered to your inbox.

Already have an account? Log in here