In January 1982, the Medical Genetics Unit of Hospital de Clinicas de Porto Alegre (HCPA) began its history in Brazil. It was elevated to a Medical Genetics Service (SGM) in 1996, and by the end of ...2016, it celebrated its 35· anniversary. This is a tale of continued progress, grounded in the idea that patient care, education, and research grow more and grow better if they are developed in harmony. In the SGM/HCPA, several units of the Federal University of Rio Grande do Sul state - UFRGS (Institute of Biosciences, Institute of Basic Health Sciences, Faculty of Medicine, Faculty of Pharmacy), and several postgraduate programs (Biochemistry, Genetics, Medical Sciences, Child and Adolescent Health, and Pharmaceutical Sciences) have become intrinsically interconnected. This heterogeneous and plural composition, acting around the central theme "Medical Genetics," became the brand of the group, which interacts transversally with numerous areas of the HCPA and has several associated sectors in the Experimental Research Center (Laboratory of Genetic Identification, Laboratory of Genomic Medicine, Gene Therapy Center, and Brain Laboratory) and the Clinical Research Center.
After the first description of a patient recognized as a MPS case was made in 1917, several similar cases were described and identified. Observations reported in the middle of the twentieth century ...concerning the presence of acid mucopolysaccharides (later called glycosaminoglycans, or GAGs) in tissues and especially in urine of patients were instrumental in providing an identity for these diseases, which became referred as "mucopolysaccharidoses" (MPS). In the late 1960's it was demonstrated that MPS were caused by defects in the breakdown of GAGs, and the specific enzyme deficiencies for the 11 types and subtypes of MPS were identified thereafter. Genes involved in the MPS were subsequently identified, and a large number of disease-causing mutations were identified in each one. Although individually rare, MPS are relatively frequent as a group, with an overall incidence estimated as 1:22,000. The increased excretion of urinary GAGs observed in the vast majority of MPS patients provides a simple screening method, the diagnosis usually being confirmed by the identification of the specific enzyme deficiency. Molecular analysis also plays a role, being helpful for phenotype prediction, prenatal diagnosis and especially for the identification of carriers. As the diseases are rare and diagnosis requires sophisticated methods, the establishment of reference laboratories for MPS identification is recommended. The successful experience of the MPS Brazil Network in providing access to information and diagnosis may be considered as an option for developing countries. The development of therapeutic strategies for MPS, including bone marrow/hematopoietic stem cell transplantation (BMT/HSCT) and enzyme replacement therapy (ERT), changed the natural history of many MPS types. However, some challenges still remain, including the prevention of cognitive decline which occurs in some MPS. Newer approaches, such as intratechal ERT, substrate reduction therapy, read-through, gene therapy and encapsulated modified cells may provide a better outcome for these diseases in the near future. As early diagnosis and early treatment seems to improve treatment outcomes, and as newborn screening is now technically feasible, pilot programs (including one in progress in an area with high-incidence of MPS VI in northeastern Brazil) should provide information about its potential impact in reducing the morbidity associated with MPS diseases.
Mucopolysaccharidosis (MPS) Type I (MPSI) is caused by mutations in the gene encoding the lysosomal enzyme, α-L-iduronidase (IDUA), and a majority of patients present with severe neurodegeneration ...and cognitive impairment. Recombinant IDUA does not cross the blood-brain barrier (BBB). To enable BBB transport, IDUA was re-engineered as an IgG-IDUA fusion protein, valanafusp alpha, where the IgG domain targets the BBB human insulin receptor to enable transport of the enzyme into the brain. We report the results of a 52-week clinical trial on the safety and efficacy of valanafusp alpha in pediatric MPSI patients with cognitive impairment. In the phase I trial, 6 adults with attenuated MPSI were administered 0.3, 1, and 3 mg/kg doses of valanafusp alpha by intravenous (IV) infusion. In the phase II trial, 11 pediatric subjects, 2-15 years of age, were treated for 52 weeks with weekly IV infusions of valanafusp alpha at 1, 3, or 6 mg/kg. Assessments of adverse events, cognitive stabilization, and somatic stabilization were made. Outcomes at 52 weeks were compared to baseline.
Drug related adverse events included infusion related reactions, with an incidence of 1.7%, and transient hypoglycemia, with an incidence of 6.4%. The pediatric subjects had CNS involvement with a mean enrollment Development Quotient (DQ) of 36.1±7.1. The DQ, and the cortical grey matter volume of brain, were stabilized by valanafusp alpha treatment. Somatic manifestations were stabilized, or improved, based on urinary glycosaminoglycan levels, hepatic and spleen volumes, and shoulder range of motion.
Clinical evidence of the cognitive and somatic stabilization indicates that valanafusp alpha is transported into both the CNS and into peripheral organs due to its dual targeting mechanism via the insulin receptor and the mannose 6-phosphate receptor. This novel fusion protein offers a pharmacologic approach to the stabilization of cognitive function in MPSI.
Clinical Trials.Gov, NCT03053089 . Retrospectively registered 9 February, 2017; Clinical Trials.Gov, NCT03071341 . Registered 6 March, 2017.
Started in 1963 by Robert Guthrie, newborn screening (NBS) is considered to be one of the great public health achievements. Its original goal was to screen newborns for conditions that could benefit ...from presymptomatic treatment, thereby reducing associated morbidity and mortality. With advances in technology, the number of disorders included in NBS programs increased. Pompe disease is a good candidate for NBS. Because decisions regarding which diseases should be included in NBS panels are made regionally and locally, programs and efforts for NBS for Pompe disease have been inconsistent both in the United States and globally. In this article, published in the "Newborn Screening, Diagnosis, and Treatment for Pompe Disease" guidance supplement, the Pompe Disease Newborn Screening Working Group, an international group of experts in both NBS and Pompe disease, review the methods used for NBS for Pompe disease and summarize results of current and ongoing NBS programs in the United States and other countries. Challenges and potential drawbacks associated with NBS also are discussed.
In this study, we aimed to describe the natural history of mucopolysaccharidosis I.
Data from 1,046 patients who enrolled in the MPS I Registry as of August 2013 were available for descriptive ...analysis. Only data from untreated patients and data prior to treatment for patients who received treatment were considered. Age at symptom onset, diagnosis, and treatment initiation were examined by geographic region and phenotype (from most to least severe: Hurler, Hurler-Scheie, and Scheie). For each symptom, frequency and age at onset were examined.
Natural history data were available for 987 patients. Most patients were from Europe (45.5%), followed by North America (34.8%), Latin America (17.3%), and Asia Pacific (2.4%). Phenotype distribution was 60.9% for Hurler, 23.0% for Hurler-Scheie, and 12.9% for Scheie (3.2% undetermined) syndromes. Median age at symptom onset for Hurler, Hurler-Scheie, and Scheie syndromes was 6 months, 1.5 years, and 5.3 years, respectively; median age at treatment initiation was 1.5 years, 8.0 years, and 16.9 years, respectively. Coarse facial features and corneal clouding were among the most common symptoms in all three phenotypes.
A delay between symptom onset and treatment exists, especially in patients with attenuated mucopolysaccharidosis I. A better understanding of disease manifestations may help facilitate prompt diagnosis and treatment and improve patient outcomes.
Migalastat stabilizes mutant α-galactosidase in Fabry's disease, reducing globotriaosylceramide deposition. In this study, the percentage of patients with a decrease of 50% or more in kidney ...interstitial capillary deposition at 6 months was similar in the migalastat and placebo groups.
Fabry’s disease is a rare, progressive, and devastating X-linked disorder caused by the functional deficiency of lysosomal α-galactosidase.
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The resultant accumulation of glycosphingolipids, predominantly globotriaosylceramide (GL-3), can lead to multisystem disease and early death.
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Binding of the pharmacologic chaperone migalastat to the active site of α-galactosidase stabilizes certain mutant enzymes, thus facilitating proper trafficking to lysosomes, where dissociation of migalastat allows α-galactosidase to catabolize accumulated substrates.
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In patients with mutant enzymes that are identified with the validated assay, orally administered migalastat may be an alternative treatment option for addressing certain unmet medical needs associated with enzyme-replacement therapy — for . . .
Outcomes in patients with Fabry disease receiving migalastat during the phase 3 FACETS trial (NCT00925301) were evaluated by phenotype.
Data were evaluated in two subgroups of patients with ...migalastat-amenable GLA variants: “classic phenotype” (n=14; males with residual peripheral blood mononuclear cell α-galactosidase A <3% normal and multiorgan system involvement) and “other patients” (n=36; males not meeting classic phenotype criteria and all females). Endpoints included estimated glomerular filtration rate (eGFR), left ventricular mass index (LVMi), Gastrointestinal Symptoms Rating Scale diarrhea subscale (GSRS-D), renal peritubular capillary (PTC) globotriaosylceramide (GL-3) inclusions, and plasma globotriaosylsphingosine (lyso-Gb3).
Baseline measures in the classic phenotype patients suggested a more severe phenotype. At month 24, mean (SD) annualized change in eGFRCKD-EPI with migalastat was −0.3 (3.76) mL/min/1.73m2 in the classic phenotype subgroup; changes in LVMi, GSRS-D, and lyso-Gb3 were −16.7 (18.64) g/m2, −0.9 (1.66), and −36.8 (35.78) nmol/L, respectively. At month 6, mean PTC GL-3 inclusions decreased with migalastat (−0.8) and increased with placebo (0.3); switching from placebo to migalastat, PTC inclusions decreased by −0.7. Numerically smaller changes in these endpoints were observed in the other patients.
Migalastat provided clinical benefit to patients with Fabry disease and amenable variants, regardless of disease severity.
To assess olipudase alfa enzyme replacement therapy for non–central nervous system manifestations of acid sphingomyelinase deficiency (ASMD) in children.
This phase 1/2, international, multicenter, ...open-label trial (ASCEND-Peds/NCT02292654) administered intravenous olipudase alfa every 2 weeks with intrapatient dose escalation to 3 mg/kg. Primary outcome was safety through week 64. Secondary outcomes included pharmacokinetics, spleen and liver volumes, lung diffusing capacity (DLCO), lipid profiles, and height through week 52.
Twenty patients were enrolled: four adolescents (12–17 years), nine children (6–11 years), and seven infants/early child (1–5 years). Most adverse events were mild or moderate, including infusion-associated reactions (primarily urticaria, pyrexia, and/or vomiting) in 11 patients. Three patients had serious treatment-related events: one with transient asymptomatic alanine aminotransferase increases, another with urticaria and rash (antidrug antibody positive ADA+), and a third with an anaphylactic reaction (ADA+) who underwent desensitization and reached the 3 mg/kg maintenance dose. Mean splenomegaly and hepatomegaly improved by >40% (p < 0.0001). Mean % predicted DLCO improved by 32.9% (p = 0.0053) in patients able to perform the test. Lipid profiles and elevated liver transaminase levels normalized. Mean height Z-scores improved by 0.56 (p < 0.0001).
In this study in children with chronic ASMD, olipudase alfa was generally well-tolerated with significant, comprehensive improvements in disease pathology across a range of clinically relevant endpoints.
Mucopolysaccharidosis VI (Maroteaux-Lamy syndrome) is a lysosomal storage disease that is characterized by systemic clinical manifestations and significant functional impairment. Diagnosis and ...management are often challenging because of the considerable variability in symptom presentation and rate of progression. The optimal standard of care should be based on evidence from randomized, controlled trials, meta-analyses, systematic reviews, and expert opinion. In support of this goal, comprehensive management guidelines have been drafted by an international group of experts in the management of patients with mucopolysaccharidosis VI. The guidelines provide a detailed outline of disease manifestations by body system, recommendations for regular assessments, and an overview of current treatment options.