Toward a Core Outcome Set for Head, Neck, and Respiratory Disease in Mucopolysaccharidosis Type II: Systematic Literature Review and Assessment of Heterogeneity in Outcome Reporting

Abstract The mucopolysaccharidoses (MPS) are a relatively uncommon group of inherited metabolic disorders, with significant negative implications for life span and aspects of quality of life. Their rarity means that producing evidence to guide best practice has often entailed assimilating findings from multiple studies. Core outcome sets (COS) are being increasingly used across medicine as a potential solution to the problems arising from heterogeneous reporting of outcomes in effectiveness studies. A COS is a recommended minimum set of outcomes that should be measured for a given condition in an effectiveness study, with the ultimate aim of increasing the value of clinical information by enabling meaningful comparison and combination of data from various sources. A systematic review identified 41 outcomes measured in published studies and ongoing and completed clinical trials, with individual outcomes being measured using a variety of measurement instruments/tools. This work represents the important initial steps in the development of COS for head, neck, and respiratory disorders in MPS type II, raising awareness of the extent of heterogeneity in outcome reporting and determining the scope of outcomes and corresponding instruments currently used. The next step will be to use the generated "longlist" of outcomes to develop an electronic Delphi prioritization exercise with the intention of reaching a consensus regarding the most important outcomes to measure in effectiveness studies for head, neck, and respiratory disease in MPS type II.

Health Related Quality of Life, Disability, and Pain in Alpha Mannosidosis: Long-Term Data of Enzyme Replacement Therapy With Velmanase Alfa (Human Recombinant Alpha Mannosidase)

Abstract Alpha-mannosidosis, a rare lysosomal storage disorder caused by deficiency of the lysosomal enzyme alpha-mannosidase, results in accumulation of mannose-rich glycoproteins in the tissues and sequelae leading to intellectual disability, ataxia, impaired hearing and speech, recurrent infections, skeletal abnormalities, muscular pain, and weakness. This study aimed to investigate disability, pain, and overall health using the Childhood Health Assessment Questionnaire (CHAQ) and the EuroQol 5 Dimension-5 Level Questionnaire (EQ-5D-5L) in patients with alpha-mannosidosis participating in rhLAMAN-10, a phase III open-label, clinical trial of velmanase alfa, a recombinanthumanlysosomalalpha-mannosidase. Long-termprognosesformost patients withuntreatedalpha-mannosidosisarepoor due to progressive neuromuscular, skeletal, and intellectual deterioration, leading to increased dependence in mobility and activities of daily living and increased caregiver and health-care burden. Long-term CHAQ and EQ-5D-5L data highlight improvement trends in health-related quality of life and a reduction in disability and pain in patients receiving up to 48 months of velmanase alfa treatment.

Long-Term Galsulfase Treatment Associated With Improved Survival of Patients With Mucopolysaccharidosis VI (Maroteaux-Lamy Syndrome): 15-Year Follow-Up From the Survey Study

Abstract Mucopolysaccharidosis VI (MPS VI) is a progressive lysosomal storage disorder with multiorgan and multisystemic pathology. Currently, galsulfase enzyme replacement therapy (ERT) is the only approved treatment for MPS VI. A crosssectional survey study of 121 patients with MPS VI conducted in 2001 to 2002 and a 10-year follow-up study of the same patients (resurvey study; ClinicalTrials.gov NCT01387854) found that those receiving galsulfase at any time showed physical improvements and a lower mortality rate (16.5%) versus treatment-naive patients (50%). After *15 years, galsulfasetreated patients (n » 104) continue to have a survival advantage over treatment-naive patients (n » 14), as demonstrated by a 24% versus 57% mortality rate. This survival advantage is further supported by data from the commercial use of galsulfase (2005-2016), which show a 5-year mortality rate for galsulfase-treated patients of 12.5%. Together, these findings suggest that galsulfase ERT can increase life expectancies for patients with MPS VI over a period of at least 15 years.

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.

Obstructive Sleep Apnea in MPS: A Systematic Review of Pretreatment and Posttreatment Prevalence and Severity

Abstract The mucopolysaccharidoses (MPSs) are a group of inherited, metabolic disorders characterized by progressive multisystem accumulation of partially degraded glycosaminoglycans. This manifests with multilevel airway obstruction, presenting with obstructive sleep apnea (OSA). We systematically reviewed the literature to determine the severity and prevalence of OSA in MPS based on polysomnography analysis. Fifteen studies with 294 participants met the inclusion criteria for review. The pretreatment prevalence of OSA in MPS was 81% with a mean apnea-hypopnea index (AHI) of 10.4. Patients with MPS I are most significantly affected, with 75% suffering with moderate to severe OSA (mean AHI, 16.6). Enzyme replacement therapy (ERT) results in an almost significant reduction in OSA in MPS I (P = .06), while adenotonsillar surgery significantly improves AHI (P = .002). Obstructive sleep apnea least affects MPS III. There is a lack of long-term post-ERT and hematopoietic stem cell transplant data relating to OSA outcomes in this population, with further prospective studies required to determine the ongoing response to treatment.