A Study of NNZ-2591 in Pediatric Participants With Phelan-McDermid Syndrome (NCT07281079) | Clinical Trial Compass
RecruitingPhase 3
A Study of NNZ-2591 in Pediatric Participants With Phelan-McDermid Syndrome
United States160 participantsStarted 2025-11-12
Plain-language summary
This Phase 3, randomized, double-blind, parallel-group (2-arm), placebo-controlled, multicenter study will evaluate the efficacy and safety of NNZ-2591 compared to placebo in pediatric participants with Phelan- McDermid Syndrome.
Who can participate
Age range
3 Years – 12 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Male or female pediatric participants with Phelan-McDermid syndrome ages 3 to 12 years (inclusive) at the time of signing the informed consent.
. Clinical diagnosis of Phelan-McDermid syndrome with a documented disease-causing genetic abnormality of SHANK3.
. Body weight ≥ 10 kg at Screening.
. Participants with a PMSA-S overall score ≥ 3 at the Screening and Baseline visits.
. Not actively undergoing regression or loss of skills.
Exclusion criteria
. Use of exclusionary medication or unstable treatment regimens of acceptable concomitant medications as required by the protocol.
. Current treatment with more than 3 allowable psychotropic medications.
. Participants with seizures must be controlled on no more than 2 anticonvulsant medications (not counting rescue medications).
. Psychotropic medications or any other medication used for a chronic illness (not including antibiotics, pain relievers, anti-diarrheals, and laxatives) with doses and dosing regimen that have not been stable for at least 4 weeks before Screening. If the treatment was discontinued, the discontinuation must have occurred no fewer than 2 weeks before the start of Screening.
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Efficacy of NNZ-2591 compared with placebo as measured by the Phelan-McDermid Syndrome Assessment of Change (PMSA-C) overall score.
Timeframe: Week 13
2
Efficacy of NNZ-2591 compared with placebo as measured by the change from baseline in the Vineland Adaptive Behavior Scales-3, Interview version (Vineland-3) receptive communication subdomain raw score.
. Any intercurrent seizures in the past 6 months and /or more than 1 seizure in the past 12 months. •A single febrile seizure in the 6 months prior to screening is allowable if no rescue medication was required.
. Abnormal liver function laboratory results during the Screening period, as defined by the protocol
. Abnormal QT interval on Screening ECG as defined by the protocol.