Assess the safety, tolerability and efficacy of GHF-201 in patients with Adult Polyglucosan Body Disease (APBD) in a pivotal phase 2/3 study.
APBD is an ultra-rare, adult-onset autosomal recessive leukodystrophy with no approved treatment. The disease is caused by glycogen branching enzyme (GBE1) deficiency leading to polyglucosan body (PB) accumulation and progressive neurodegeneration. GHF-201 is a novel small molecule demonstrated to enhance autophagic flux and improve survival and motor parameters in several mouse models of glycogen and lysosomal storage diseases (GSDs/LSDs), including APBD. Additionally, GHF-201 was associated with clinically meaningful benefits in 3 APBD patients participating in a compassionate use program with ~12 patient-years of follow-up. GHF-201 also showed no safety issues in a phase I study in healthy volunteers.
Study GHF-201-02-APBD will be a phase 2/3 adaptive design study. The first stage will be a randomized, placebo-controlled, double-blind trial evaluating the efficacy and safety of two doses of GHF-201 compared to placebo in APBD patients over ~24 weeks (Cohort 1). The second stage is informed by a comparative interim analysis (IA) supporting a confirmatory assessment of the optimal dose of GHF-201 and treatment duration determined during the IA (Cohort 2). Various clinician/ observer-based (ClinRo; ObsRO), performance-based (PerfO), patient-reported (PRO) endpoints, as well as MRI, biomarkers (PB burden, neurofilament light chain) and natural history will provide a totality-of-evidence review.
The safety, clinical efficacy, and biomarker results from the ongoing compassionate use program support the examination of GHF-201 in this pivotal study. An updated study design will be presented at the meeting.
This innovative, adaptive trial design is intended to maximize efficiency by leveraging advanced statistical methodologies and incorporating biomarker and real-world data to detect clinically meaningful benefits in APBD. Findings may support accelerated approval of GHF-201 as the first targeted therapy for APBD.