A phase 3 randomized study evaluating sialic acid extended-release for GNE myopathy

Area of Science:

• Neurology
• Rare Diseases
• Pharmacology

Background:

• GNE myopathy is a rare, progressive neuromuscular disorder characterized by muscle weakness.
• Aceneuramic acid extended-release (Ace-ER) is designed to address sialic acid deficiency in GNE myopathy.
• Investigating novel therapeutic strategies is crucial for managing GNE myopathy.

Purpose of the Study:

• To evaluate the efficacy and safety of Ace-ER compared to placebo in patients with GNE myopathy.
• To determine if Ace-ER can improve muscle strength and function in this patient population.
• To assess the impact of Ace-ER on key functional endpoints over a 48-week treatment period.

Main Methods:

• A Phase 3, double-blind, placebo-controlled, randomized international study (UX001-CL301) was conducted.
• Eighty-nine patients with GNE myopathy were randomized to receive Ace-ER or placebo for 48 weeks.
• Muscle strength was assessed using upper extremity composite (UEC) and lower extremity composite (LEC) scores, knee extensor strength, and the GNEM-FAS mobility domain.

Main Results:

• No significant difference was observed in the primary endpoint, change in UEC score, between the Ace-ER and placebo groups.
• Key secondary endpoints, including LEC score, knee extensor strength, and GNEM-FAS mobility, also showed no significant improvement with Ace-ER.
• Gastrointestinal events were the most frequently reported adverse events in the Ace-ER group.

Conclusions:

• Ace-ER did not demonstrate superiority over placebo in enhancing muscle strength or function in patients with GNE myopathy.
• The study provides Class I evidence that Ace-ER is not effective for treating GNE myopathy.
• Further research may be needed to explore alternative therapeutic approaches for GNE myopathy.