Chaperonas farmacológicas. Nueva alternativa terapéutica para la nefropatía por enfermedad de Fabry en Argentina

La enfermedad de Fabry (EF, OMIM 301500) es una enfermedad por depósito lisosomal (EDL). Este grupo de enfermedades incluye al menos cincuenta entidades  hereditarias de baja frecuencia, originadas por un error congénito del metabolismo, secundario a un defecto génico específico, que conduce a una deficiencia en la actividad de una o varias enzimas lisosomales. El déficit de actividad enzimática produce el acúmulo anormal de productos no metabolizados, primariamente en los lisosomas celulares. La EF es una EDL causada por la actividad deficiente de la enzima α-galactosidasa-A (αGal-A, EC 3.2.1.22), lo que produce la acumulación de glicoesfingolípidos complejos, principalmente globotriaosilceramida (Gb3) (Galα1→4Galβ1→4Glcβ→Cer, Gb3) y sus metabolitos asociados, en los lisosomas, otros compartimientos celulares y el plasma de manera progresiva y multisistémica

Fabry Disease: Switch from Enzyme Replacement Therapy to Oral Chaperone Migalastat: What Do We Know Today?

Fabry disease is a lysosomal storage disorder caused by the deficiency of the α-galactosidase-A enzyme. The result is the progressive accumulation of complex glycosphingolipids and cellular dysfunction. Cardiac, renal, and neurological involvement significantly reduces life expectancy. Currently, there is increasing evidence that clinical response to treatment improves with early and timely initiation. Until a few years ago, treatment options for Fabry disease were limited to enzyme replacement therapy with agalsidase alfa or beta administered by intravenous infusion every 2 weeks. Migalastat (Galafold®) is an oral pharmacological chaperone that increases the enzyme activity of “amenable” mutations. The safety and efficacy of migalastat were supported in the phase III FACETS and ATTRACT studies, compared to available enzyme replacement therapies, showing a reduction in left ventricular mass, and stabilization of kidney function and plasma Lyso-Gb3. Similar results were confirmed in subsequent extension publications, both in patients who started migalastat as their first treatment and in patients who were previously on enzyme replacement therapy and switched to migalastat. In this review we describe the safety and efficacy of switching from enzyme replacement therapy to migalastat in patients with Fabry disease and “amenable” mutations, referring to publications available to date

Fabry Disease: Switch from Enzyme Replacement Therapy to Oral Chaperone Migalastat: What Do We Know Today?

Fabry disease is a lysosomal storage disorder caused by the deficiency of the α-galactosidase-A enzyme. The result is the progressive accumulation of complex glycosphingolipids and cellular dysfunction. Cardiac, renal, and neurological involvement significantly reduces life expectancy. Currently, there is increasing evidence that clinical response to treatment improves with early and timely initiation. Until a few years ago, treatment options for Fabry disease were limited to enzyme replacement therapy with agalsidase alfa or beta administered by intravenous infusion every 2 weeks. Migalastat (Galafold®) is an oral pharmacological chaperone that increases the enzyme activity of “amenable” mutations. The safety and efficacy of migalastat were supported in the phase III FACETS and ATTRACT studies, compared to available enzyme replacement therapies, showing a reduction in left ventricular mass, and stabilization of kidney function and plasma Lyso-Gb3. Similar results were confirmed in subsequent extension publications, both in patients who started migalastat as their first treatment and in patients who were previously on enzyme replacement therapy and switched to migalastat. In this review we describe the safety and efficacy of switching from enzyme replacement therapy to migalastat in patients with Fabry disease and “amenable” mutations, referring to publications available to date

Migalastat as oral monotherapy for Fabry disease

Contexto: la enfermedad de Fabry es una patología de depósito lisosomal poco frecuente, ligada al cromosoma X y causada por la deficiencia o ausencia de la enzima ?-galactosidasa-A. La nefropatía, junto con la cardiopatía y el compromiso neurológico de la enfermedad, conduce a una muerte prematura. Objetivo: esta revisión describe la monoterapia oral con migalastat en pacientes con enfermedad de Fabry y mutaciones “amenables”. Metodología: una chaperona farmacológica oral denominada migalastat (Galafold®), estabiliza y favorece el pasaje de formas mutadas “amenables” de la enzima hacia los lisosomas, aumentando así su actividad. Resultados: los estudios de fase III Facets y Attract demostraron seguridad y eficacia en comparación con las terapias de reemplazo enzimático disponibles, alcanzando estabilización de la función renal, reducción de la masa ventricular izquierda y estabilización del biomarcador plasmático Lyso-Gb3. Conclusiones: migalastat fue generalmente bien tolerado en ambos estudios. Publicaciones posteriores de extensión evidenciaron resultados similares, confirmando la seguridad y la eficacia, tanto en pacientes que previamente se encontraban con terapia de reemplazo enzimático y han sido rotados a migalastat, como también en pacientes que han iniciado migalastat como primer tratamiento.Background: Fabry disease is a rare lysosomal storage disorder, linked to the X chromosome, and caused by the deficiency or absence of the enzyme ?-galactosidase-A. Nephropathy together with heart disease and neurological involvement lead to premature death. Purpose: This review describes oral migalastat monotherapy in patients with Fabry disease and “amenable” mutations. Methodology: An oral pharmacological chaperone called Migalastat (Galafold®), stabilizes and facilitates the trafficking of “amenable” mutated forms of the enzyme to the lysosomes, thus increasing its activity. Results: The phase III FACETS and ATTRACT studies have demonstrated safety and efficacy compared to available enzyme replacement therapies; achieving renal function stabilization, reduction of left ventricular mass and maintenance of plasmatic Lyso-Gb3 levels. Conclusions: Migalastat was generally well tolerated in both trials. Subsequent extension publications showed similar results, confirming the safety and efficacy both in patients who were previously on enzyme replacement therapy and have been switched to migalastat, as well as in patients who have started migalastat as their first treatment

Nefropatía por enfermedad de Fabry. Rol del nefrólogo y variables clínicas asociadas al diagnóstico

Resumen: Antecedentes: La detección temprana de la nefropatía por enfermedad de Fabry es de interés, pues su tratamiento es más eficaz en estadios precoces. Ha sido estudiada por biomarcadores moleculares y tisulares, pero estos poseen desventajas que dificultan su uso rutinario. El propósito del presente trabajo es describir el rol del nefrólogo en el diagnóstico de la enfermedad y las variables clínicas asociadas a nefropatía en pacientes afectados. Material y métodos: Estudio transversal. Se incluyeron pacientes de tres centros de referencia de Argentina. Resultados: Se estudiaron 72 pacientes (26,26 ± 16,48 años): 30 (41,6%) varones y 42 (58,4%) mujeres; 27 pediátricos y 45 adultos. Se detectaron 14 «casos índice», el 50% diagnosticados por nefrólogos. Se halló nefropatía en 44 pacientes (61%): 6 pediátricos y 38 adultos. Dos tipos de variables clínicas se asociaron a nefropatía: a) compromiso del sistema nervioso periférico (p ≤ 0,001), angioqueratomas (p ≤ 0,001) y compromiso auditivo (p = 0,01-0,001), siendo estas manifestaciones clínicas tempranas del fenotipo más severo de la enfermedad, y b) cardiopatía estructural (p = 0,01-0,001) y compromiso del sistema nervioso central (p = 0,05-0,01), que son complicaciones mayores y tardías, responsables de la morbimortalidad aumentada y la menor expectativa de vida. Conclusión: El nefrólogo cumple un rol importante en el diagnóstico de la enfermedad de Fabry, ya que aunque la detección de esta por su compromiso renal significaría diagnóstico tardío, debido a que la nefropatía se asocia a complicaciones tardías del fenotipo más severo de la enfermedad. Abstract: Background: The early detection of Fabry nephropathy is of interest to us. Its treatment is more effective in early stages. It has been studied by analysing molecular and tissue biomarkers. These have certain disadvantages that hinder its routine use. The aim of this study is to describe the role of the nephrologist in the diagnosis of the disease, and to describe the clinical variables associated with nephropathy in affected patients. Material and methods: Cross-sectional study. Patients were included from three reference centres in Argentina. Results: Seventy two patients were studied (26.26 ± 16.48 years): 30 of which (41.6%) were men and 42 of which (58.4%) were women; 27 paediatric patients and 45 adults. Fourteen “index cases” were detected, 50% of which were diagnosed by nephrologists. Nephropathy was found in 44 patients (61%): 6 paediatric patients and 38 adults. Two types of clinical variables were associated with nephropathy: (i) peripheral nervous system compromise (P ≤ .001), angiokeratomas (P ≤ .001) and auditory compromise (P = .01-.001), with these being early clinical manifestations of the most severe disease phenotype, and (ii) structural heart disease (P = .01-.001) and central nervous system compromise (P = .05-.01), which are major and late complications, responsible for increased morbidity and mortality and lower life expectancy. Conclusion: The nephrologist plays an important role in the diagnosis of Fabry nephropathy, although the detection thereof owing to its renal involvement would represent a late diagnosis, because nephropathy is associated with late complications of the most severe disease phenotype. Palabras clave: Enfermedad de Fabry, Nefropatía, Proteinuria, Diagnóstico temprano, Keywords: Fabry disease, Nephropathy, Proteinuria, Early diagnosi

Major Organic Involvement in Women with Fabry Disease in Argentina

Fabry disease (FD) is an X-linked lysosomal storage disorder resulting from the deficiency or absence of the alpha galactosidase A enzyme. Organic involvement in men is well known, but in women it is controversial, partly due to the random X-chromosomes inactivation (Lyon hypothesis). The aim of this study was to describe the organic involvement in women at the time of FD diagnosis. A descriptive, cross-sectional and multicenter study was carried out. Thirty-five women with FD from three reference centers in Argentina were evaluated. The mean age of the whole group (n=35) was 26.6±16.9 years; 22 were adult (over 18) and 13 were paediatric patients. Enzymatic activity was performed in 29/35 patients, which was normal in 24/29 (82.8%). Seven different mutations of the GLA gene were found. The results showed urinary protein loss (45.7%) and decreased glomerular filtration rate (31.4%), mainly in adults. And also, cornea verticillata (56.5%), peripheral neuropathy (51.4%), cardiovascular manifestations (31.4%), hearing loss (20%), angiokeratomas (20%), central nervous system (17.1%), and gastrointestinal involvement (14.3%). Organic compromise in females with FD may be as severe as in men. This analysis has demonstrated a significant proportion of women with signs, symptoms, and major organic involvement at FD diagnosis

Prevalence of chronic kidney disease in fabry disease patients: Multicenter cross sectional study in Argentina

Nephropathy is one of the major complications of Fabry Disease (FD) and mainly includes reduced glomerular filtration rate (GFR) and proteinuria. Despite the frequency, scarce information exists regarding the frequency of CKD as well as other related complications in FD patients in Argentina. The aim of the study was to measure the prevalence of CKD at diagnosis of FD as well as to describe other related conditions in a large cohort of patients with FD. Methods: a cross-sectional study performed in three FD centers of Argentina during January 2014 and January 2016. Information at diagnosis regarding patient demographics, disease characteristics, key laboratory values, and renal, cardiac, cerebrovascular diseases and other related complications were collected. Results: A total of 60 patients were included. The mean age at diagnosis was 25.5 ± 16 years. 42% of included patients presented CKD in which the disease was mild (GFR ≥60 and <90) in 60% (n = 15), moderate (GFR ≥30 and <60) in 16% (n = 4), severe (GFR ≥15 and <30) in 4% (n = 1) and failure (GFR <15) in 20% (n = 5). Arrhythmias were reported for 13.3% of patients. In 33.3% the echocardiographic evaluation demonstrated left ventricular hypertrophy and peripheral neuropathy in 63.3%. Conclusion: This study presents information regarding the prevalence of CKD in a large cohort of FD patients at the moment of diagnosis in Argentina. Future studies will help us to confirm these initial findings

Early Renal Involvement in a Girl with Classic Fabry Disease

Fabry disease is an X-linked lysosomal storage disorder resulting from the deficiency or absence of the enzyme alpha galactosidase A; this defect leads to the systemic accumulation of globotriaosylceramide and its metabolites. Organic involvement in men is well known, but in women it is controversial, mainly due to the random X-chromosome inactivation in each of their cells (Lyon hypothesis). This would explain why women (heterozygotes) present a wide variability in the severity of their phenotype. The manifestations are multisystemic and begin in early childhood, reaching a severe compromise in adulthood. Typical acroparesthesia in hands and feet, gastrointestinal symptoms, angiokeratomas, dyshidrosis, hearing loss, arrhythmias, hypertrophic cardiomyopathy, cerebrovascular accidents, and renal failure can be observed. Nephropathy is one of the major complications of Fabry disease. Glomerular and vascular changes are present before progression to overt proteinuria and decreased glomerular filtration rate, even in pediatric patients. A case of incipient renal involvement in a girl with classic Fabry disease is reported

Baseline Characteristics of Fabry Disease “Amenable” Migalastat Patients in Argentinian Cohort

Fabry disease (FD) is a multisystem lysosomal storage disorder induced by genetic variants in the alpha-galactosidase A (αGalA) gene. Some FD patients have GLA variants with a reduction in overall αGalA enzymatic activity due to mutated proteins with reduced stability, caused by protein misfolding and premature degradation, but the αGalA catalytic activity remains conserved (“amenable” genetic variants). To correct this misfolding and to prevent premature degradation, migalastat, a small iminosugar molecule was developed. We report the clinical characteristics of FD “amenable” cohort patients from Argentina, prior to starting treatment with migalastat. Seventeen Fabry adult patients were recruited from 13 Argentinian Centers; 8 males (47.1%) and 9 females (52.9%) were included. All genotypes included were missense-type “amenables” mutations. Some classic FD typical early manifestations were more frequent in patients with “classic” versus “late-onset” FD phenotype (pain, p=0.002; cornea verticillata, p=0.019). There was a statistically significant difference in estimated glomerular filtration rate in the “classic” versus “late-onset” phenotype (p=0.026) but no difference between genders (p=0.695). Left ventricular mass was similar between genders (p=0.145) and phenotypes (p=0.303). Cardiovascular risk factors were present among “late-onset” females (obesity 50% and smoke 25%). In patients who started “de novo” migalastat, the main indications were (i) heart disease, (ii) kidney damage, and (iii) pain, while in “switched from prior enzyme replacement therapy” patients, the most frequent indication was “patient decision;” this coincides with publications by other authors