While FSHD can manifest at any age, the onset of symptoms in many patients occurs before the age of 18. We refer to this patient population as early onset FSHD. We have selected those patients with onset of symptoms before the age of 10 for our current clinical trial. Within the early onset population are individuals with symptom onset at less than five years of age, with progression in disease prior to age ten. These individuals have the most severe muscle symptoms and significant extra-muscular manifestations such as auditory deficits and retinal complications that may result in vision loss. This sub-group of early onset patients are often referred to as having “infantile onset” FSHD. Estimates of prevalence vary, however we believe the domestic “infantile onset” FSHD population is approximately 1,000.
Natural History Study Collaboration:
We recently entered into collaboration with The Cooperative International Neuromuscular Research Group (CINRG) on a longitudinal natural history study, comprised of 53 patients, to advance knowledge of early onset FSHD.
We provide financial support to this study, which was initially implemented by the FSH Society, the FSHD Global Research Foundation and Muscular Dystrophy Canada.