The SPARKLE study: Shedding light on alpha mannosidosis.

Alpha-mannosidosis (AM) is a lysosomal storage disorder caused by reduced activity of the enzyme alpha-mannosidase, leading to intracellular accumulation of mannose-rich oligosaccharides in various organs. Velmanase alfa (VA) is a human recombinant alpha-mannosidase approved in Europe in 2018 as enzyme replacement therapy for the treatment of non-neurological manifestations in mild to moderate AM patients. A post-authorization safety and efficacy registry called SPARKLE was designed as a multi-centre, multi-national, non-interventional, prospective cohort study. SPARKLE has two objectives. The first is to assess post-marketing safety and effectiveness of VA (product registry) the second is to gain new understanding of the natural course of AM (disease registry). In terms of effectiveness, the primary focus is to estimate the treatment response rate based on a multi-parametric response model. The effectiveness assessment includes the measurement of serum oligosaccharides, serum immunoglobulin G levels, endurance, pulmonary function, hearing tests, incidence of infections, use of antibiotics, psychotic events, questionnaires on quality of life and burden of disease for caregivers, among others. All patients affected by AM can participate into the registry, regardless of their treatment. Based on the current protocol, the study will be opened for participation for an indefinite time and each patient will be followed up for 15 years. The protocol does not foresee a pre-specified sample size and aims at including most of the patients treated with VA in clinical practice. The SPARKLE study will start in Europe in the second half of 2019. [ABSTRACT FROM AUTHOR]