Long-Term Cardiorespiratory, Endocrine, Ophthalmic, and Functional Outcomes in Adult Patients with Mucopolysaccharidosis Type I (Hurler Syndrome) Post Haematopoietic Stem Cell Transplantation: The Irish Experience

Abstract Mucopolysaccharidosis type IH (MPS IH) is caused by homozygous IDUA gene pathogenic variants. This results in deficiency of the enzyme α-L-iduronidase (IDUA), which is necessary for the degradation of glycosaminoglycans (GAGs). This study outlines the long-term outcomes in adult Irish patients affected with MPS IH, who were followed up for mean 28 years post Haematopoietic Stem Cell Transplantation. Nineteen adult MPS IH patients underwent HSCT in childhood. The participant cohort represents 6 families. Among the 13 patients with Irish Traveller ethnicity, 6 patients were either siblings or first cousins. All these related patients were homozygous for p. Trp402Ter (W402X). Mean age at the first transplantation was 8 months (range 3-21). Five patients had undergone a second transplantation (n=5, 26%) in childhood, due to graft failure. None of the patients had a cardiac valve surgery at the time of the study. 14/19 patients had mild to moderate aortic or mitral valve insufficiency or stenosis. 3/19 patients used non-invasive ventilation at night. Two patients had tracheostomy in situ. Both sensorineural as well as conductive hearing defects. No corneal clouding post corneal transplantation (n=8) was observed. Six patients attended regular secondary school. Multidisciplinary follow-up is needed to address the disease specific complications in adulthood.

Impact of Elosulfase Alfa on Pain in Patients with Morquio A Syndrome over 52 Weeks: MOR-008: A Randomized, Double-Blind, Pilot Study

Abstract Patients with mucopolysaccharidosis (MPS), and Morquio A syndrome (MPS IVA) in particular, often report substantial pain burden. MOR-008 was a randomized, double-blind, pilot study assessing the safety and efficacy, including impact on patient-reported pain, of 52 weeks of treatment with elosulfase alfa (at a dose of 2.0 or 4.0 mg/kg/week) in patients with Morquio A syndrome (?7 years old). Assessment of pain at baseline revealed that patients (N = 25) had a mean number of pain locations of 5.7, mean pain intensity score of 4.6 (indicative of medium pain), and a mean number of selected pain descriptors of 7.4 words. Treatment with elosulfase alfa improved subjective pain score (reduced to 3.2), pain locations (reduced by a mean of 1 location), and pain descriptor words (reduced to 4.9 words) over 1 year (52 weeks), suggesting that elosulfase alfa can reduce pain in some patients with Morquio A.