Safety and Effects of Intrathecal ION440 in Males with MECP2 Duplication Syndrome Aged 2 to 65 Years

What this Trial Is About

Researchers are evaluating the safety, tolerability, pharmacokinetics, and pharmacodynamics of the drug ION440 in people with Methyl CpG Binding Protein 2 MECP2 Duplication Syndrome MDS. This phase 1-2 randomized, double-blind, sham-controlled study includes both pediatric and adult participants to better understand how ION440 affects this rare genetic condition. The study is sponsored by Ionis Pharmaceuticals, Inc. and aims to carefully monitor treatment impacts over time. Participants will be randomly assigned to receive one of three different doses of ION440 or a sham procedure during the first part of the study, which lasts about 36 weeks. ION440 is given by injection into the spinal fluid intrathecal bolus. After completing the first part, participants may enter a second open-label extension lasting up to approximately 156 weeks, where they receive the same dose of ION440 as before. The study includes two age groups children aged 2 to 7 years and participants aged 8 to 65 years. The dosing groups are evaluated sequentially, starting with the older group. During the study, participants will undergo physical and neurological exams, vital sign checks, lab tests, electrocardiograms, and monitoring for any adverse effects. Blood and cerebrospinal fluid samples will be collected to measure drug levels. The study will assess the number of participants experiencing treatment-related side effects and changes in health markers over both the initial 36-week period and the longer extension. Participants are expected to complete all study visits and procedures to support these evaluations, which together may last more than three years.

ATTUNE: A Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Intrathecally-Administered ION440 in Participants With Methyl CpG Binding Protein 2 (MECP2) Duplication Syndrome (MDS)