Short Communication Impact of early enzyme-replacement therapy for mucopolysaccharidosis VI: results of a long-term follow-up of Brazilian siblings.

Mucopolysaccharidosis type VI (MPS VI) is an autosomal recessive multisystem lysosomal storage disorder, which is characterized by the deficiency of the enzyme arylsulfatase B encoded by the ARSB gene. Treatment of this disease with enzyme-replacement therapy (ERT) improves the clinical status of and generates hope for MPS VI patients. However, only few reports on patients with MPS VI treated before 5 years of age have been published. Thus, the objective of this study was to compare the clinical parameters of two sisters affected by MPS VI who started ERT at different ages (9 years and 1 year 5 months, respectively) and to determine the most relevant clinical impacts of early treatment after 85 months of evaluation. The treatment was well tolerated by both siblings. ERT in the younger sibling resulted in increased growth, an improved 6-minute walk test, less coarse face, slower progression of cardiac valve disease, and the absence of compressive myelopathy compared to that in her older sister. On the other hand, the older sibling had typical MPS VI phenotypic features before the commencement of ERT. Corneal clouding, clawed hands, and progressive skeletal changes were observed in both siblings despite the treatment. Both siblings displayed reduced frequencies of upper respiratory infections and apnea indices. This study emphasizes that early diagnosis and treatment of MPS VI are critical for a better disease outcome and to enhance the quality of life for these patients.

Evolução do estado nutricional na doença de Gaucher tipo I em tratamento com reposição enzimática - relato de dois casos / The evolution of nutritional status in type I Gaucher’s disease treated with enzyme replacement - two case histories

A doença de Gaucher é um erro do metabolismo enzimático que leva ao acúmulo de glicocerebrosídeo nas células, o que caracteriza os sinais e sintomas da doença. No momento do diagnóstico, além de outros sinais e sintomas, é observado retardo no crescimento em crianças e adolescentes. O tratamento é realizado por meio de reposição enzimática, que pode ocasionar ganho de peso no paciente pela diminuição do metabolismo energético. Descrição: dois irmãos com diagnóstico de doença de Gaucher tipo I foram avaliados antes de iniciarem a reposição enzimática e depois a cada 2 meses de tratamento, por um período de 6 meses. A composição corporal foi avaliada por impedância bioelétrica, que avaliou a quantidade de massa livre de gordura e massa de gordura; o consumo energético e a relação de macronutrientes foram avaliados por registro alimentar de 3 dias. Discussão: os dois pacientes apresentavam baixa estatura para idade ao diagnóstico e tiveram aumento de massa de gordura durante o tratamento, sendo que um paciente também apresentou aumento da massa livre de gordura. O consumo energético e a relação de macronutrientes mantiveram-se semelhantes durante todo o período de acompanhamento para ambos os pacientes...

Gaucher’s disease is flaw in enzyme metabolism that leads to the accumulation of glycocerebrosides in cells that characterizes the signs and symptoms of the condition. At the time of diagnosis, retarded growth, among other signs and symptoms, is observed in children and adolescents. The disease is treated by enzyme replacement, which may lead to weight gain in the patient, owing to the reduction in energy metabolism. Description: two brothers diagnosed with type I Gaucher’s disease were evaluated prior to commencing enzyme replacement therapy and subsequently after every two months of treatment, for a period of six months. Body composition was assessed using bioelectrical impedance, which measures the quantity of fat-free and fat mass; energy consumption and macronutrients were evaluated using a three-day food diary. Discussion: the two patients were of low height for age on diagnosis and had experienced an increase in fat mass during treatment, with one patient also presenting with an increase in fat free mass. Energy consumption and macronutrients remained fairly constant during the follow-up period in both patients...

Laronidase-functionalized multiple-wall lipid-core nanocapsules: promising formulation for a more effective treatment of mucopolysaccharidosis type I.

PURPOSE: Mucopolysaccharidosis I is a genetic disorder caused by alpha-L-iduronidase deficiency. Its primary treatment is enzyme replacement therapy (ERT), which has limitations such as a high cost and a need for repeated infusions over the patient's lifetime. Considering that nanotechnological approaches may enhance enzyme delivery to organs and can reduce the dosage thereby enhancing ERT efficiency and/or reducing its cost, we synthesized laronidase surface-functionalized lipid-core nanocapsules (L-MLNC). METHODS: L-MLNCs were synthesized by using a metal complex. Size distributions were evaluated by laser diffraction and dynamic light scattering. The kinetic properties, cytotoxicity, cell uptake mechanisms, clearance profile and biodistribution were evaluated. RESULTS: Size distributions showed a D[4,3] of 134 nm and a z-average diameter of 71 nm. L-MLNC enhanced the Vmax and Kcat in comparison with laronidase. L-MLNC is not cytotoxic, and nanocapsule uptake by active transport is not only mediated by mannose-6-phosphate receptors. The clearance profile is better for L-MLNC than for laronidase. A biodistribution analysis showed enhanced enzyme activity in different organs within 4 h and 24 h for L-MLNC. CONCLUSIONS: The use of lipid-core nanocapsules as building blocks to synthesize surface-functionalized nanocapsules represents a new platform for producing decorated soft nanoparticles that are able to modify drug biodistribution.

Enzyme replacement therapy with galsulfase in 34 children younger than five years of age with MPS VI.

BACKGROUND: Mucopolysaccharidosis type VI (MPS VI) is a progressive, chronic and multisystem lysosomal storage disease with a wide disease spectrum. Clinical and biochemical improvements have been reported for MPS VI patients on enzyme replacement therapy (ERT) with rhASB (recombinant human arylsulfatase B; galsulfase, Naglazyme®, BioMarin Pharmaceutical Inc.), making early diagnosis and intervention imperative for optimal patient outcomes. Few studies have included children younger than five years of age. This report describes 34 MPS VI patients that started treatment with galsulfase before five years of age. METHODS: Data from patients who initiated treatment at <5 years of age were collected from patients' medical records. Baseline and follow-up assessments of common symptoms that led to diagnosis and that were used to evaluate disease progression and treatment efficacy were evaluated. RESULTS: A significant negative correlation was seen with treatment with ERT and urinary GAG levels. Of those with baseline and follow-up growth data, 47% remained on their pre-treatment growth curve or moved to a higher percentile after treatment. Of the 9 patients with baseline and follow-up sleep studies, 5 remained unaffected and 1 patient initially with mild sleep apnea showed improvement. Data regarding cardiac, ophthalmic, central nervous system, hearing, surgical interventions and development are also reported. No patient discontinued treatment due to an adverse event and all that were treatment-emergent resolved. CONCLUSIONS: The prescribed dosage of 1mg/kg IV weekly with galsulfase ERT is shown to be safe and effective in slowing and/or improving certain aspects of the disease, although patients should be closely monitored for complications associated with the natural history of the disease, especially cardiac valve involvement and spinal cord compression. A long-term follow-up investigation of this group of children will provide further information on the benefits of early treatment as well as disease progression and treatment efficacy and safety in this young patient population.