GNE Myopathy is a rare genetic (autosomal recessive) disorder that causes progressive skeletal muscle atrophy and weakness. Previous names include hereditary inclusion body myopathy (HIBM), inclusion body myopathy type 2 (IBM2) or Nonaka myopathy.
Symptoms of the disease usually appear between 20 and 40 years of age and include foot drop and difficulty walking. The disease slowly affects other muscles of the arms and legs. Patients typically start using a wheelchair one or two decades later and eventually some patients may need assistance with activities of daily living.
GNE myopathy results from mutations in a gene called GNE, which is responsible for a step in the production of a sugar called sialic acid. GNE myopathy is diagnosed in patients presenting at the age of 20-40 with foot drop and progressive muscle weakness. Red-rimmed vacuoles (inclusions) are found on muscle biopsy. The diagnosis is confirmed by sequencing of the GNE gene.
GNE myopathy patients may go undiagnosed for many years. There are ~2,000 patients known worldwide and ~200 in the United States. However, we estimate (based on examining DNA sequencing databases) that there are at least 40,000 GNE myopathy patients worldwide, including ~13,000 in Asia (~750 in Japan), ~4,000 in Europe and ~3,000 in North America, meaning that many patients are undiagnosed.
No therapies are currently approved for GNE myopathy. Studies on mouse models of GNE myopathy have provided promising data and several therapeutic trials are currently underway. NIH investigators are developing ManNAc as a therapy for GNE myopathy.
Studies on GNE Myopaty Currently Recruiting
An Open-Label Phase 2 Study ManNAc in Subjects with GNE Myopathy [clinicaltrials.gov]
Multicenter Trial of ManNAc for GNE Myopathy
Coming in 2017
Nuria Carrillo, M.D.
Last Updated: February 13, 2017