Treatment of Fabry Disease management with migalastat-outcome from a prospective 24 months observational multicenter study (FAMOUS).

AIMS: Fabry disease (FD) is an X-linked lysosomal storage disorder caused by a deficiency of the lysosomal enzyme α-galactosidase A (GLA/AGAL), resulting in the lysosomal accumulation of globotriaosylceramide (Gb3). Patients with amenable GLA mutations can be treated with migalastat, an oral pharmacological chaperone increasing endogenous AGAL activity. In this prospective observational multicentre study, safety as well as cardiovascular, renal, and patient-reported outcomes and disease biomarkers were assessed after 12 and 24 months of migalastat treatment under 'real-world' conditions. METHODS AND RESULTS: A total of 54 patients (26 females) (33 of these [61.1%] pre-treated with enzyme replacement therapy) with amenable mutations were analysed. Treatment was generally safe and well tolerated. A total of 153 events per 1000 patient-years were detected. Overall left ventricular mass index decreased after 24 months (all: -7.5 ± 17.4 g/m2, P = 0.0118; females: -4.6 ± 9.1 g/m2, P = 0.0554; males: -9.9 ± 22.2 g/m2, P = 0.0699). After 24 months, females and males presented with a moderate yearly loss of estimated glomerular filtration rate (-2.6 and -4.4 mL/min/1.73 m2 per year; P = 0.0317 and P = 0.0028, respectively). FD-specific manifestations/symptoms remained stable (all P > 0.05). A total of 76.9% of females and 50% of males suffered from pain, which has not improved under treatment. FD-specific disease scores (Disease Severity Scoring System and Mainz Severity Score Index) remained stable during treatment. AGAL activities and plasma lyso-Gb3 values remained stable, although some male patients presented with increasing lyso-Gb3 levels over time. CONCLUSIONS: Treatment with migalastat was generally safe and resulted in most patients in an amelioration of left ventricular mass. However, due to the heterogeneity of FD phenotypes, it is advisable that the treating physician monitors the clinical response regularly.

Analysis of Renal and Cardiac Outcomes in Male Participants in the Fabry Outcome Survey Starting Agalsidase Alfa Enzyme Replacement Therapy Before and After 18 Years of Age.

PURPOSE: To determine the impact of initiating enzyme replacement therapy (ERT) with agalsidase alfa early in the course of Fabry disease, we evaluated renal and cardiac outcomes for ≤10 years after ERT initiation in males from the Fabry Outcome Survey (FOS). PATIENTS AND METHODS: Male patients from FOS were stratified into three cohorts by age at ERT initiation: ≤18 years (cohort 1), >18 and ≤30 years (cohort 2), and >30 years (cohort 3). Analysis included age at symptom onset, diagnosis, and ERT initiation; ERT duration; FOS-Mainz Severity Score Index (FOS-MSSI); estimated glomerular filtration rate (eGFR); proteinuria level; and left ventricular mass indexed to height (LVMI). Mixed-effect models estimated renal and cardiac outcomes during follow-up between and within cohorts. FINDINGS: The analysis included 560 male patients: 151 (27.0%) in cohort 1, 155 (27.7%) in cohort 2, and 254 (45.4%) in cohort 3. Mean±SD duration of ERT for cohorts 1, 2, and 3 was 6.3±4.3, 8.6±4.9, and 7.9±4.9 years, respectively. Mean±SD baseline FOS-MSSI scores increased with age from 9.8±7.2 in cohort 1 to 24.7±11.4 in cohort 3. Cohort 3 showed the lowest baseline mean±SD value for eGFR (87.1±29.0 mL/min/1.73m2) and highest baseline mean±SD values for proteinuria (801.9±952.6 mg/day) and LVMI (56.7±16.0 g/m2.7) among the three cohorts. Evaluation of mean annual rates of change in eGFR, proteinuria, and LVMI revealed no significant differences in any parameter for cohort 1. For cohort 2, proteinuria and LVMI remained stable, whereas eGFR significantly deteriorated annually (-1.12 mL/min/1.73m2; P<0.001). Cohort 3 demonstrated significant annual deteriorations in eGFR (-2.60 mL/min/1.73m2; P<0.001), proteinuria (+34.10 mg/day; P<0.001), and LVMI (+0.59 g/m2.7; P=0.001). IMPLICATIONS: Renal and/or cardiac disease progression appears attenuated in patients starting ERT in childhood or early adulthood versus patients starting ERT in later adulthood. These findings support early ERT initiation in Fabry disease. ClinicalTrials.gov identifier: NCT03289065.

Treatment of Fabry's Disease With Migalastat: Outcome From a Prospective Observational Multicenter Study (FAMOUS).

Fabry's disease (FD) is an X-linked lysosomal storage disorder caused by the deficient activity of the lysosomal enzyme α-galactosidase A (α-Gal A) leading to intracellular accumulation of globotriaosylceramide (Gb3). Patients with amenable mutations can be treated with migalastat, a recently approved oral pharmacologic chaperone to increase endogenous α-Gal A activity. We assessed safety along with cardiovascular, renal, and patient-reported outcomes and disease biomarkers in a prospective observational multicenter study after 12 months of migalastat treatment under "real-world" conditions. Fifty-nine (28 females) patients (34 (57.6%) pretreated with enzyme replacement therapy) with amenable mutations were recruited. Migalastat was generally safe and well tolerated. Females and males presented with a reduction of left ventricular mass index (primary end point) (-7.2 and -13.7 g/m2 , P = 0.0050 and P = 0.0061). FD-specific manifestations and symptoms remained stable (all P > 0.05). Both sexes presented with a reduction of estimated glomerular filtration rate (secondary end point) (-6.9 and -5.0 mL/minute/1.73 m2 ; P = 0.0020 and P = 0.0004, respectively), which was most prominent in patients with low blood pressure (P = 0.0271). α-Gal A activity increased in male patients by 15% from 29% to 44% of the normal wild-type activity (P = 0.0106) and plasma lyso-Gb3 levels were stable in females and males (P = 0.3490 and P = 0.2009). Reevaluation of mutations with poor biochemical response revealed no marked activity increase in a zero activity background. We conclude that therapy with migalastat was generally safe and resulted in an amelioration of left ventricular mass. In terms of impaired renal function, blood pressure control seems to be an unattended important goal.

Paediatric Fabry disease: prognostic significance of ocular changes for disease severity.

BACKGROUND: Ocular signs of Fabry disease can be seen in the first decade of life. METHODS: We examined the occurrence of ocular signs in 232 paediatric patients in the Fabry Outcome Survey (FOS) international registry and looked for relationships between the presence of eye findings and disease severity as measured by the FOS Mainz severity score index (FOS-MSSI). RESULTS: At least one ocular sign was found in 55/101 (54.5%) girls and 62/131 (47.3%) boys: cornea verticillata in 53/101 (52.5%) girls and 55/131 (42.0%) boys, vessel tortuosity in 17/98 (17.3%) girls and 32/131 (24.4%) boys, and posterior spoke-like lens opacities in 3/97 (3.1%) girls and 2/130 (1.5%) boys. Summary statistics showed higher median (range) age-adjusted FOS-MSSI total score indicating more severe disease in children with eye findings versus those without eye findings (0.5 [-11.0, 20.7] versus -2.3 [-11.1, 18.8]). At least one eye finding was observed in 59.1% of treated and 37.9% of untreated children. CONCLUSIONS: We conclude that the presence of ocular signs, particularly cornea verticillata, correlates with more severe disease as indicated by FOS-MSSI scores in paediatric patients with Fabry disease. Ocular signs appear in roughly half of school-aged children with Fabry disease and are well-recognised as a valuable tool for diagnosis of Fabry disease in children; they also may help identify patients who are at risk for developing early severe manifestations of Fabry disease and who should be further evaluated and closely followed up.

Multicenter Female Fabry Study (MFFS) - clinical survey on current treatment of females with Fabry disease.

BACKGROUND: The aim of the present study was to assess manifestations of and applied treatment concepts for females with Fabry disease (FD) according to the current European Fabry Guidelines. METHODS: Between 10/2008 and 12/2014, data from the most recent visit of 261 adult female FD patients from six German Fabry centers were retrospectively analyzed. Clinical presentation and laboratory data, including plasma lyso-Gb3 levels were assessed. RESULTS: Fifty-five percent of females were on enzyme replacement therapy (ERT), according to recent European FD guidelines. Thirty-three percent of females were untreated although criteria for ERT initiation were fulfilled. In general, the presence of left ventricular hypertrophy (LVH) seemed to impact more on ERT initiation than impaired renal function. In ERT-naïve females RAAS blockers were more often prescribed if LVH was present rather than albuminuria. Affected females with missense mutations showed a similar disease burden compared to females with nonsense mutations. Elevated plasma lyso-Gb3 levels in ERT-naïve females seem to be a marker of disease burden, since patients showed comparable incidences of organ manifestations even if they were ~8 years younger than females with normal lyso-Gb3 levels. CONCLUSION: The treatment of the majority of females with FD in Germany is in line with the current European FD guidelines. However, a relevant number of females remain untreated despite organ involvement, necessitating a careful reevaluation of these females.

D313Y mutation in the differential diagnosis of white matter lesions: Experiences from a multiple sclerosis outpatient clinic.

White matter lesions (WML) in younger patients might be due to a variety of neurological disorders. Fabry disease (FD), an x-linked inherited lysosomal storage disorder, happens to be misdiagnosed as multiple sclerosis (MS). In two middle-aged female patients, presenting bilateral WML, diagnosis of MS turned out to be doubtful. Human genetic analysis presented the Fabry mutation D313Y, in which clinical impact is still unclear. Disease manifestations outside the central nervous system were not detected. Our findings support the suspicion that Fabry mutation D313Y may be involved in neural damage resulting in WML.

Recommendations for initiation and cessation of enzyme replacement therapy in patients with Fabry disease: the European Fabry Working Group consensus document.

INTRODUCTION: Fabry disease (FD) is a lysosomal storage disorder resulting in progressive nervous system, kidney and heart disease. Enzyme replacement therapy (ERT) may halt or attenuate disease progression. Since administration is burdensome and expensive, appropriate use is mandatory. We aimed to define European consensus recommendations for the initiation and cessation of ERT in patients with FD. METHODS: A Delphi procedure was conducted with an online survey (n = 28) and a meeting (n = 15). Patient organization representatives were present at the meeting to give their views. Recommendations were accepted with ≥75% agreement and no disagreement. RESULTS: For classically affected males, consensus was achieved that ERT is recommended as soon as there are early clinical signs of kidney, heart or brain involvement, but may be considered in patients of ≥16 years in the absence of clinical signs or symptoms of organ involvement. Classically affected females and males with non-classical FD should be treated as soon as there are early clinical signs of kidney, heart or brain involvement, while treatment may be considered in females with non-classical FD with early clinical signs that are considered to be due to FD. Consensus was achieved that treatment should not be withheld from patients with severe renal insufficiency (GFR < 45 ml/min/1.73 m(2)) and from those on dialysis or with cognitive decline, but carefully considered on an individual basis. Stopping ERT may be considered in patients with end stage FD or other co-morbidities, leading to a life expectancy of <1 year. In those with cognitive decline of any cause, or lack of response for 1 year when the sole indication for ERT is neuropathic pain, stopping ERT may be considered. Also, in patients with end stage renal disease, without an option for renal transplantation, in combination with advanced heart failure (NYHA class IV), cessation of ERT should be considered. ERT in patients who are non-compliant or fail to attend regularly at visits should be stopped. CONCLUSION: The recommendations can be used as a benchmark for initiation and cessation of ERT, although final decisions should be made on an individual basis. Future collaborative efforts are needed for optimization of these recommendations.

Ocular signs correlate well with disease severity and genotype in Fabry disease.

Ocular signs in Fabry disease have generally been regarded to be primarily of diagnostic value. We explored whether ocular findings, alone or in particular in combination with the α-galactosidase A gene mutation, have predictive value for disease severity. Data from the Fabry Outcome Survey (FOS), a large, global database sponsored by Shire, were selected for adult patients who had undergone ophthalmological examination. Three ocular signs were assessed: cornea verticillata, tortuous conjunctival and/or retinal vessels, and cataract. Fabry disease severity was measured using FOS Mainz Severity Score Index and modifications thereof. Ophthalmological data were available for 1203 (699 female, 504 male) adult patients with eye findings characteristic of Fabry disease in 55.1%. Cornea verticillata had a similar distribution in women (51.1%) and men (50.8%), whereas tortuous vessels and Fabry cataract were somewhat more frequent in men than in women. Patients with cornea verticillata, selected as the principal ocular sign for this study, had more severe disease (median score, 20.0) versus those without ocular signs (11.0; P<0.001). This finding could be confirmed by applying age adjusted severity scores. Moreover, the prevalence of cornea verticillata was significantly higher in patients with null (male, 76.9%; female, 64.5%) and missense (male, 79.2%; female, 67.4%) mutations versus mild missense (male, 17.1%; female, 23.1%) and the p.N215S (male, 15.0%; female, 15.6%) mutations (P<0.01). Our analyses show a correlation between the prevalence of ocular changes in Fabry disease and disease severity. Consequently, information on ocular findings and α-galactosidase A gene mutation may help assess the risk for more severe Fabry disease. These observed findings are of notable clinical importance, as Fabry disease is characterized by high clinical course variability and only weak genotype-phenotype correlation at the individual patient level. Further confirmatory studies are needed.

Thromboembolic events in Fabry disease and the impact of factor V Leiden.

OBJECTIVES: Although several reports suggest an increased thromboembolic event rate, especially regarding strokes and TIAs at early age in patients with Fabry disease (FD), the risk for patients with FD to experience these events, the clinical relevance of additional risk factors including the concurrence of factor V Leiden (FVL), and the benefit of enzyme replacement therapy (ERT) regarding these events remain unclear. METHODS: Three hundred four consecutively recruited patients with FD were evaluated for their lifetime occurrence of thromboembolic events such as stroke, TIA, deep vein thrombosis, and pulmonary embolism. The thromboembolic risk was determined in patients with FD and concurrent FVL, and the impact of ERT was assessed. RESULTS: The 304 patients with FD had a median age of 41 years and 53 (17.4%) had experienced at least one thromboembolic event during their lifetime. Among 226 patients with FD screened for FVL, 16 gene carriers were identified (7.1%). The occurrence of thromboembolic events in patients with FD and concurrent FVL was significantly increased compared to those without FVL (hazard ratio = 5.45, 95% confidence interval 2.29-12.99; p < 0.001). Patients with FD receiving ERT had a significantly decreased risk of thromboembolic events compared to those without ERT (hazard ratio = 0.362, 95% confidence interval 0.132-0.992; p = 0.0422). CONCLUSION: This observational study confirms that patients with FD have a high risk of clinically relevant thromboembolic events, which could be aggravated by a concurrence of FVL. ERT might be of benefit in preventing vascular events in patients with FD. The latter observation needs confirmation, however, by randomized and controlled clinical trials.

Dose responsive effects of subcutaneous pentosan polysulfate injection in mucopolysaccharidosis type VI rats and comparison to oral treatment.

BACKGROUND: We previously demonstrated the benefits of daily, oral pentosan polysulfate (PPS) treatment in a rat model of mucopolysaccharidosis (MPS) type VI. Herein we compare these effects to once weekly, subcutaneous (s.c.) injection. The bioavailability of injected PPS is greater than oral, suggesting better delivery to difficult tissues such as bone and cartilage. Injected PPS also effectively treats osteoarthritis in animals, and has shown success in osteoarthritis patients. METHODOLOGY/PRINCIPAL FINDINGS: One-month-old MPS VI rats were given once weekly s.c. injections of PPS (1, 2 and 4 mg/kg, human equivalent dose (HED)), or daily oral PPS (4 mg/kg HED) for 6 months. Serum inflammatory markers and total glycosaminoglycans (GAGs) were measured, as were several histological, morphological and functional endpoints. Overall, weekly s.c. PPS injections led to similar or greater therapeutic effects as daily oral administration. Common findings between the two treatment approaches included reduced serum inflammatory markers, improved dentition and skull lengths, reduced tracheal deformities, and improved mobility. Enhanced effects of s.c. treatment included GAG reduction in urine and tissues, greater endurance on a rotarod, and better improvements in articular cartilage and bone in some dose groups. Optimal therapeutic effects were observed at 2 mg/kg, s.c.. No drug-related increases in liver enzymes, coagulation factor abnormalities or other adverse effects were identified following 6 months of s.c. PPS administration. CONCLUSIONS: Once weekly s.c. administration of PPS in MPS VI rats led to equal or better therapeutic effects than daily oral administration, including a surprising reduction in urine and tissue GAGs. No adverse effects from s.c. PPS administration were observed over the 6-month study period.

Mucopolysaccharidoses and other lysosomal storage diseases.

Mucopolysaccharidosis and other lysosomal storage diseases are rare, chronic, and progressive inherited diseases caused by a deficit of lysosomal enzymes. Patients are affected by a wide variety of symptoms. For some lysosomal storage diseases, effective treatments to arrest disease progression, or slow the pathologic process, and increase patient life expectancy are available or being developed. Timely diagnosis is crucial. Rheumatologists, orthopedics, and neurologists are commonly consulted due to unspecific musculoskeletal signs and symptoms. Pain, stiffness, contractures of joints in absence of clinical signs of inflammation, bone pain or abnormalities, osteopenia, osteonecrosis, secondary osteoarthritis or hip dysplasia are the alerting symptoms that should induce suspicion of a lysosomal storage disease.