Study of the effect of anti-rhGAA antibodies at low and intermediate titers in late onset Pompe patients treated with ERT.

Late onset Pompe disease (LOPD) is a genetic disorder characterized by slowly progressive skeletal and respiratory muscle weakness. Symptomatic patients are treated with enzyme replacement therapy (ERT) with alglucosidase alpha (rhGAA). Although most of ERT treated patients develop antibodies against rhGAA, their influence on clinical progression is not completely known. We studied the impact of anti-rhGAA antibodies on clinical progression of 25 ERT treated patients. We evaluated patients at visit 0 and, after 1 year, at visit 1. We performed several muscle function tests, conventional spirometry and quantitative muscle MRI (qMRI) using 3-point Dixon analysis of thigh muscles at both visits. We also obtained serum samples at both visits and anti-rhGAA antibodies were quantified using ELISA. Antibody titers higher than 1:200 were identified in 18 patients (72%) of our cohort. Seven patients (28%) did not develop antibodies (0 to <1:200), 17 patients (68%) developed low to intermediate titers (1:200 to <1:31,200) and 1 patient (4%) developed high titers (>1:31,200). We analyzed the effect of low and intermediate antibody titers in clinical and radiological progression. There were no differences between the results of muscle function tests, spirometry or fat fraction analyzed using qMRI between patients with and without antibodies groups at baseline. Moreover, antibody titers did not influence muscle function test, spirometry results or qMRI results at year 1 visit. Most of the LOPD patients developed antibodies against ERT that persisted over time at low or intermediate levels. However, antibodies at these low and intermediate titers might not influence clinical response to the drug.

Gender Differences in the Application of Spanish Criteria for Initiation of Enzyme Replacement Therapy for Fabry Disease in the Fabry Outcome Survey.

Both male/female patients with Fabry disease (FD) may receive enzyme replacement therapy (ERT). Previously published analyses of the Fabry Outcome Survey (FOS; Shire-sponsored) database suggested gender differences in timing of ERT initiation. We assessed alignment of criteria for ERT initiation in the Spanish adult population included in FOS with recommendations of a Spanish national consensus. This retrospective analysis examined baseline clinical data of 88 adults (49 females) enrolled in the FOS database up to August 2014. Thirty-five (39.8%) patients were not receiving ERT: five (12.8%) males and 30 (61.2%) females. Baseline disease severity on the FOS-derived Mainz Severity Score Index was lower in untreated males (median (interquartile range), 0.0 (0.0-1.0)) than treated males (TM; 15.0 (7.5-26.5)), and was similar in untreated and treated females. The percentage of untreated females with at least one criterion for treatment initiation was 76.7% versus 100.0% of treated females (p = 0.0340) and 97.1% (p = 0.0210) of TM. In discordance with Spanish consensus recommendations, a substantial number of females with evidence of FD who might benefit from ERT have not yet initiated treatment. These results suggest unequal gender perceptions with respect to ERT initiation in Spain.

Description of clinical and genetic features of 122 patients included in the Spanish Pompe registry.

Pompe disease is a rare genetic disorder with an estimated prevalence of 1:60.000. The two main phenotypes are Infantile Onset Pompe Disease (IOPD) and Late Onset Pompe Disease (LOPD). There is no published data from Spain regarding the existing number of cases, regional distribution, clinical features or, access and response to the treatment. We created a registry to collect all these data from patients with Pompe in Spain. Here, we report the data of the 122 patients registered including nine IOPD and 113 LOPD patients. There was a high variability in how the diagnosis was obtained and how the follow-up was performed among different centres. Seven IOPD patients were still alive being all treated with enzymatic replacement therapy (ERT) at last visit. Ninety four of the 113 LOPD patients had muscle weakness of which 81 were receiving ERT. We observed a progressive decline in the results of muscle function tests during follow-up. Overall, the Spanish Pompe Registry is a valuable resource for understanding the demographics, patient's journey and clinical characteristics of patients in Spain. Our data supports the development of agreed guidelines to ensure that the care provided to the patients is standardized across the country.

Screening for late-onset Pompe disease in Internal Medicine departments in Spain.

BACKGROUND: The screening of high-risk populations using dried blood spots (DBS) has allowed the rapid identification of patients with Pompe disease, mostly in Neurology departments. The aim of the study was to determine the prevalence of late-onset Pompe disease (LOPD) among patients not previously diagnosed or tested for this entity despite presenting possible signs or symptoms of the disease in Internal Medicine departments in Spain. METHODS: This epidemiological, observational, cross-sectional, multicenter study included a single cohort of individuals with clinical suspicion of LOPD seen at Internal Medicine departments in Spain. The diagnosis of LOPD was initially established on the basis of the result of DBS. If decreased enzyme acid-alpha-1,4-glucosidase (GAA) activity was detected in DBS, additional confirmatory diagnostic measurements were conducted, including GAA activity in lymphocytes, fibroblasts, or muscle and/or genetic testing. RESULTS: The diagnosis of LOPD was confirmed in 2 out of 322 patients (0.6%). Reasons for suspecting LOPD diagnosis were polymyositis or any type of myopathy of unknown etiology (in one patient), and asymptomatic or pauci-symptomatic hyperCKemia (in the other). The time between symptom onset and LOPD diagnosis was 2.0 and 0.0 years. Both patients were asymptomatic, with no muscle weakness. Additionally, 19.7% of the non-LOPD cases received an alternative diagnosis. CONCLUSIONS: Our study highlights the existence of a hidden population of LOPD patients in Internal Medicine departments who might benefit from early diagnosis and early initiation of potential treatments.

Response of women with Fabry disease to enzyme replacement therapy: comparison with men, using data from FOS--the Fabry Outcome Survey.

Fabry disease (α-galactosidase A deficiency) is an X-linked disorder. Women who are heterozygous for disease-causing mutations often manifest signs and symptoms of Fabry disease, but most studies of the effects of enzyme replacement therapy (ERT) have included only men. To date, no direct comparison has been made of the relative effectiveness of long-term ERT between men and women. The aim of this analysis was to report the effectiveness of agalsidase alfa in a cohort of 78 women treated for 4 years and to compare outcomes with those of 172 men. All data were obtained from the Fabry Outcome Survey--an international database of patients with Fabry disease sponsored by Shire Human Genetic Therapies. Quantifiable clinical parameters were assessed at baseline and the 4-year time point. Measures of pain, health-related quality of life, cardiac structure and function, and renal function changed to a similar extent in women and men during treatment, with the exception of left ventricular mass, which only reduced significantly in women. Changes in the presence of each of 27 clinical features after 4 years of ERT were evaluated in two subpopulations: patients with and patients without clinical features at baseline. It was clear for most types of clinical features that a number of women with a feature at baseline were no longer reported to have it at the 4-year time point, and that clinical features were observed in only a small percentage of women in whom they had been absent at baseline. The percentage of patients who were symptomatic at the 4-year time point was calculated for each type of clinical feature. The results showed no significant differences between men and women for most clinical features evaluated. Overall, both sexes responded to agalsidase alfa in a similar way, suggesting there should be no difference in the criteria for assessment of treatment in women and men.

Novel GAA Variants and Mosaicism in Pompe Disease Identified by Extended Analyses of Patients with an Incomplete DNA Diagnosis.

Pompe disease is a metabolic disorder caused by a deficiency of the glycogen-hydrolyzing lysosomal enzyme acid α-glucosidase (GAA), which leads to progressive muscle wasting. This autosomal-recessive disorder is the result of disease-associated variants located in the GAA gene. In the present study, we performed extended molecular diagnostic analysis to identify novel disease-associated variants in six suspected Pompe patients from four different families for which conventional diagnostic assays were insufficient. Additional assays, such as a generic-splicing assay, minigene analysis, SNP array analysis, and targeted Sanger sequencing, allowed the identification of an exonic deletion, a promoter deletion, and a novel splicing variant located in the 5' UTR. Furthermore, we describe the diagnostic process for an infantile patient with an atypical phenotype, consisting of left ventricular hypertrophy but no signs of muscle weakness or motor problems. This led to the identification of a genetic mosaicism for a very severe GAA variant caused by a segmental uniparental isodisomy (UPD). With this study, we aim to emphasize the need for additional analyses to detect new disease-associated GAA variants and non-Mendelian genotypes in Pompe disease where conventional DNA diagnostic assays are insufficient.

Clinical profile of women diagnosed with Fabry disease non receiving enzyme replacement therapy.

INTRODUCTION AND OBJECTIVE: Fabry disease (FD) is an X-linked lysosomal storage disorder due to a deficiency of the α-galactosidase A enzyme. Although women were historically considered only carriers, many studies have contradicted this fact. The main aim of this work was to set the first Spanish study out of the on-going registries on health status and management of women diagnosed with FD who were not receiving enzyme replacement therapy (ERT). MATERIAL AND METHODS: An epidemiological, cross-sectional, descriptive and multicentre study was assessed in women diagnosed for FD who were not receiving ERT. Assessments on symptomatology and severity were collected using several clinical questionnaires. Additionally, clinical information and lab tests were obtained from clinical records. RESULTS: Thirty-three women with a mean age of 45.6±16.2 years were studied. Symptom onset was at a median age of 35.5 years old (range: 30.0-51.5), being diagnosed a median of 2 years later (range: 1.0-1.5). Missense mutations were the most prevalent mutation (n=22, 68.8%). Although 69% considered themselves as asymptomatic, 22 (66.7%) showed at least one FD-related clinical symptom. Using Mainz Severity Score index and Fabry International Prognosis Index neurological symptomatology obtained higher scores both for severity and prognostic. The EQ-5D questionnaire showed 42.2% patients referring to some anxiety or depression, and 30.3% thought that their life was somehow altered by the pain. 62.5% were not receiving any treatment and ERT was offered only to one patient (3.6%) who refused it. CONCLUSIONS: Although most of the heterozygous women for FD had not received ERT or either symptomatic treatment, they present symptoms of disease. Careful follow-up of female patients or some adjuvant treatment may be considered to delay progressive organ damage and improve patient quality of life.

Long-term effect of 2 intensive statin regimens on treatment and incidence of cardiovascular events in familial hypercholesterolemia: The SAFEHEART study.

BACKGROUND: Maximal doses of potent statins are the basement of treatment of familial hypercholesterolemia (FH). Little is known about the use of different statin regimens in FH. OBJECTIVES: The objectives of the study were to describe the treatment changes and low-density lipoprotein cholesterol (LDL-C) goal achievement with atorvastatin (ATV) and rosuvastatin (RV) in the SAFEHEART cohort, as well as to analyze the incidence of atherosclerotic cardiovascular events (ACVEs) and changes in the cardiovascular risk. METHODS: SAFEHEART is a prospective follow-up nationwide cohort study in a molecularly defined FH population. The patients were contacted on a yearly basis to obtain relevant changes in life habits, medication, and ACVEs. RESULTS: A total of 1939 patients were analyzed. Median follow-up was 6.6 years (5-10). The estimated 10-year risk according the SAFEHEART risk equation was 1.61 (0.67-3.39) and 1.22 (0.54-2.93) at enrollment for ATV and RV, respectively (P < .001). There were no significant differences at the follow-up: 1.29 (0.54-2.82) and 1.22 (0.54-2.76) in the ATV and RV groups, respectively (P = .51). Sixteen percent of patients in primary prevention with ATV and 18% with RV achieved an LDL-C <100 mg/dL and 4% in secondary prevention with ATV and 5% with RV achieved an LDL-C <70 mg/dL. The use of ezetimibe was marginally greater in the RV group. One hundred sixty ACVEs occurred during follow-up, being its incidence rate 1.1 events/100 patient-years in the ATV group and 1.2 in the RV group (P = .58). CONCLUSION: ATV and RV are 2 high-potency statins widely used in FH. Although the reduction in LDL-C levels was greater with RV than with ATV, the superiority of RV for reducing ACVEs was not demonstrated.

Quantification of urinary derivatives of Phenylbutyric and Benzoic acids by LC-MS/MS as treatment compliance biomarkers in Urea Cycle disorders.

PURPOSE: Salts of phenylacetic acid (PAA) and phenylbutyric acid (PBA) have been used for nitrogen elimination as a treatment for hyperammonaemia caused by urea cycle disorders (UCD). A new analytical method for PBA measurement in urine which helps to evaluate the drug adherence has been implemented. METHODS: Urine specimens from UCD patients receiving PBA were analysed by tandem mass spectrometry to measure urine phenylacetylglutamine (PAGln). Some clinical and biochemical data for each patient were collected. RESULTS: Our study included 87 samples from 40 UCD patients. The PAGln levels did not correlate with height, weight or age. However, the PAGln values showed correlation with PBA dose (r = 0.383, P = 0.015). Plasma glutamine and ammonia levels presented a positive correlation (r = 0.537, P < 0.001). The stability for PAGln in urine was determined at different storage temperatures. CONCLUSIONS: We have developed a simple method for the determination of PAGln in urine, which acts as useful biomarker of effective drug delivery. PAGln in urine is stable at room temperature at least for 15 days, and for several months when frozen at -20 °C. This procedure is useful for the optimization and monitorization of the drug dose allowing the use of spot urine samples.

[Fabry disease in Spain: first analysis of the response to enzyme replacement therapy]. / Enfermedad de Fabry en España: primer análisis de la respuesta al tratamiento de sustitución enzimática.

BACKGROUND AND OBJECTIVE: Fabry disease is a X-linked lysosomal disorder caused by a deficient activity of the enzyme alfa-galactosidase A. Lack of enzyme activity results in progressive accumulation of globotriaosylceramide (Gb3) leading to multiorgan dysfunction and early death. Enzyme replacement therapy (ERT) has recently become available and the database Fabry Outcome Survey (FOS) of Spain gives us the opportunity to asses the efficacy of this therapy. Our objective is to describe the safety and the effects on renal, cardiac and neurological (pain) aspects of ERT with agalsidase alfa. PATIENTS AND METHOD: The effects of 1, 2, 3 and 4 years of ERT with agalsidase alfa on renal function (assessed by estimated glomerular filtration rate), proteinuria, heart size (assessed by echocardiography), arrhythmias, cardiac valvular anomalies and pain (assessed by the need of concomitant pain therapy) were analyzed in 33 patients under treatment. Safety of ERT was assessed by the reported infusion-related reactions in FOS. RESULTS: Overall, treatment with agalsidase alfa stabilized renal function, but the final result depends on the onset of ERT: there is a tendency to stabilization of renal function in those patients with mild deterioration of renal function, a tendency to improve in those patients with moderate deterioration and to worse in those with severe deterioration of renal function. Proteinuria and left ventricular heart size also estabilized under ERT, and pain improved. TSE infusion-related reactions occurred with an incidence of 0.7%. CONCLUSIONS: ERT with agalsidase alfa is safe and stabilized the abnormal clinical parameters observed in patients with Fabry disease.

[Fabry's disease in Spain. Study of 24 cases]. / Enfermedad de Fabry en España. Análisis de 24 casos.

BACKGROUND AND OBJECTIVE: Fabry's disease is a rare metabolic disorder inherited as an X-linked trait resulting from a decreased activity of the alpha-galactosidase A lysosomal enzyme. This defect leads to an accumulation of unmetabolized neutral glycosphingolipids in all cell types. This condition displays a high rate of early mortality and affects both hemizygous males and heterozygous females. We present data from Spanish patients admitted to the Fabry Outcome Survey (FOS), a multicenter European registry for patients suffering from Fabry's disease, at the time of their inclusion. PATIENTS AND METHOD: The study presents baseline data from 24 Spanish patients upon inclusion in the registry, with an analysis of their overall clinical characteristics and relationship to gender. RESULTS: The median age of onset of symptoms was 13 years, while it was 25.5 years for diagnosis. In 7 patients, the manifestations of the disease had been attributed to other processes. Predominant manifestations in males were angiokeratomas (86%), pain (71%), cardiovascular involvement (71%), kidney involvement (50%), digestive symptoms (43%) and ophthalmologic complications (43%). Among females, ophthalmologic complications were present in 50%, followed by cardiovascular involvement (40%); 30% of females had a painful clinical condition which is characteristic of the process. CONCLUSIONS: We present the clinical characteristics of the largest Spanish cohort of Fabry's disease sufferers reported so far. Due to the wide spectrum of clinical manifestations, their awareness allows an early diagnosis as well as the possibility of starting the specific therapy currently available.

[Comparison of patients from a Spanish Registry of Fabry disease in two periods]. / Comparación de los pacientes de un registro español de enfermedad de Fabry en dos periodos de tiempo.

BACKGROUND AND OBJECTIVE: Fabry disease (FD) is a rare X-linked lysosomal storage disorder caused by a deficiency of the enzyme alpha-galactosidase A, that leads to multiorgan dysfunction and premature death. Data from the first 24 Spanish patients enrolled on the Fabry Outcome Survey (FOS) were published in 2004, with a significant increase in the number of patients since then. This manuscript analyzes whether the clinical profile or diagnosis of these patients between the 2 periods has changed. PATIENTS AND METHODS: In 2009 the FOS included data from 92 patients. Patients included up to 2003 and those included after that year (68) were compared by sex, regarding age at onset of symptoms and diagnosis, severity and previous misdiagnoses. Similar analysis was performed between the index cases (31) and the other patients. RESULTS: Mean delay in diagnosis was 10 years for both sexes. Male had a classic phenotype, and up to 40% of the females reported symptoms. In females, the enzyme activity seemed to determine disease severity. No differences were observed in any parameter when comparing the patients included in the first period to those included afterwards, nor when comparing index cases with the rest of the patients. CONCLUSIONS: Registries like FOS have a great value to deepen our understanding of rare diseases. We confirm that women are not just carriers of the disease. There is still a lack of education and awareness in order to include FD in the differential diagnosis of other processes. Complete family studies would allow early diagnosis of this disorder.