RecruitingPhase 3Drug trialA Study of NNZ-2591 in Pediatric Participants With Phelan-McDermid SyndromeThis 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.