Cognitive and adaptive measurement endpoints for clinical trials in mucopolysaccharidoses types I, II, and III: A review of the literature

• Published in: Molecular genetics and metabolism 2017-06, Vol.121 (2), p.57-69
• Main Authors: Janzen, Darren, Delaney, Kathleen A., Shapiro, Elsa G.
• Format: Article
• Language: English
• Subjects: Adaptive skills; Brain - physiopathology; Clinical trials; Clinical Trials as Topic - methods; Cognition; Delphi Technique; Endpoint Determination; Humans; Mucopolysaccharidoses - diagnosis; Mucopolysaccharidoses - physiopathology; Mucopolysaccharidoses - therapy; Mucopolysaccharidosis; Mucopolysaccharidosis I - diagnosis; Mucopolysaccharidosis I - therapy; Neurocognition
• ISSN: 1096-7192; 1096-7206
• DOI: 10.1016/j.ymgme.2017.05.005

Sensitive, reliable measurement instruments are critical for the evaluation of disease progression and new treatments that affect the brain in the mucopolysaccharidoses (MPS). MPS I, II, and III have early onset clinical phenotypes that affect the brain during development and result in devastating cognitive decline and ultimately death without treatment. Comparisons of outcomes are hindered by diverse protocols and approaches to assessment including applicability to international trials necessary in rare diseases. We review both cognitive and adaptive measures with the goal of providing evidence to a Delphi panel to come to a consensus about recommendations for clinical trials for various age groups. The results of the consensus panel are reported in an accompanying article. The following data were gathered (from internet resources and from test manuals) for each measure and summarized in the discussion: reliability, validity, date and adequacy of normative data, applicability of the measure's metrics, cross cultural validity including translations and adaptations, feasibility in the MPS population, familiarity to sites, sensitivity to change, and interpretability. If, resulting from this consensus, standard protocols are used for both natural history and treatment studies, patients, their families, and health care providers will benefit from the ability to compare study outcomes. •Neuronopathic mucopolysacchardoses require consistent protocols to measure functional outcomes in clinical trials.•This literature review identifies cognitive and adaptive measures that will be most effective for clinical trials.•Specific criteria used were reliability, validity, normative data, metrics, cultural validity, sensitivity, feasibility.•These comparative data regarding tests and procedures will provide increased accuracy in clinical trials.