2025 Volume 42 Issue 4 Pages 609-613
GNE myopathy is rare muscle disease affecting distal muscles like tibialis anterior. GNE gene, which encodes for a key enzyme in the sialic acid biosynthesis pathway, is mutated in the homozygote or compound heterozygote manner. The lack of sialic acid in skeletal muscle is the critical pathological process in GNE myopathy. Sialic acid supplementation to a presymptomatic GNE myopathy mouse model was effective in preventing the development of the disease. Phase 1 clinical trial in Japan was conducted at Tohoku University Hospital using aceneuramic acid, followed by the trials using slow–release product. Several clinical studies have been conducted to evaluate the safety and efficacy of sialic acid supplementation in humans. Based on the favorable results of these studies, an extended–release aceneuramic acid formulation was approved for treatment of GNE myopathy in Japan in March 2024. It is anticipated that it will be a significant step in the development of an effective treatment for GNE myopathy and other ultra–orphan diseases.
