A Study to Assess the Efficacy and Safety of Weekly Doses of GLM101 in Participants With PMM2-CDG

This Phase 2b, multicenter, randomized, double-blind, placebo-controlled clinical study is designed to evaluate the efficacy, safety, and pharmacokinetics (PK) of GLM101 in adult, adolescent, and pediatric participants with PMM2-CDG. The study is structured into: a 4-week Screening Period, a 24-week Double-blind Treatment Period (Part A) to assess primary efficacy, a 24-week Open-label Extension Period (Part B), and a safety follow-up visit conducted 4 weeks after the last infusion. In Part A, participants will be randomly assigned to receive weekly intravenous infusions of either GLM101 at 30 mg/kg or a placebo for 24 weeks. After the end of Part A, participants will transition into Part B, a 24-week open-label extension where all participants will receive GLM101. The primary objective of the trial is to identify changes from baseline in coordination and muscle movement (ataxia) using the International Co-operative Ataxia Rating Scale (ICARS) after 24 weeks of taking GLM101 compared to a placebo in PMM2-CDG patients.