Clinical features of two Japanese siblings of neuronal ceroid lipofuscinosis type 1 (CLN1) complicated with Typeâ ¡ diabetes mellitus.

Neuronal ceroid lipofuscinosis type1(CLN1), is a one form of the group of neuronal ceroid lipofuscinoses (NCLs), which is a neurodegenerative disorder characterized by progressive psychomotor deterioration, ataxia, epilepsy, and visual impairment. Neurological manifestations occur at a wide range of ages, from infancy to adulthood, but are most common in infancy. The prevalence of CLN1 is unclear; however, it is very rare in Japan and Europe. In Japan, only a few cases have been reported, two of infantile- and one of juvenile-onset type. Nonetheless, the clinical characteristics of Japanese patients and their relationship with the genotype have not been sufficiently investigated. Here, we report the cases of two siblings that presented with juvenile-onset (a 22-year-old man and a 29-year-old woman) CLN1 associated with type II diabetes mellitus. In both cases, visual impairment followed by learning disability was observed from school-age, and retinitis pigmentosa was noted on ophthalmological examination. These patients presented type II diabetes mellitus during their later teenage years. Brain magnetic resonance imaging (MRI) revealed marked atrophy of the cerebrum and cerebellum. The clinical symptoms lead to suspect NCLs. Decreased PPT1 enzyme activity in dried blood spot (DBS)and leukocytes were observed, and the genetic analysis revealed heterozygous missense variants in PPT1, c.550G > A/c.664 A > G (p. Glu184Lys/p. Lys216Glu). The latter variant of this patients was novel variant. The residual enzymatic activity of PPT1 in these cases is higher than that in the infantile type. CLN1 mutant cells are known to have altered subcellular expression and localization, enhanced lipid raft-mediated endocytosis, abnormal autophagy, and mitochondrial dysfunction. Although the prevalence of diabetes mellitus is high and the possibility of coincidental complications cannot be ruled out, we concluded that mitochondrial abnormalities are involved in insulin resistance and may be implicated in the development of type II diabetes mellitus. Further studies are needed to prove the correlation between CLN1 and diabetes mellitus.

Safety and tolerability of agalsidase beta infusions shorter than 90 min in patients with Fabry disease: post-hoc analysis of a Japanese post-marketing study.

BACKGROUND: Agalsidase beta, an enzyme replacement therapy for Fabry disease, is dosed biweekly at 1 mg/kg body weight, with increasing infusion rates based on tolerability. The US label specifies ≥ 90-min infusions for all patients; the US and EU labels require ≤ 15 mg/hr infusions in patients < 30 kg. The Japanese label allows infusions up to 30 mg/hr, allowing < 90-min dosing for some patients weighing < 45 kg. Japanese post-marketing data were analyzed for rate of infusion-associated reactions (IARs), adverse events (AEs), and serious AEs (SAEs) based on infusion rate and patient attributes (weight, antibody status). RESULTS: Data were available for 436 reduced-duration infusions (< 90 min) and 2242 standard infusions (≥ 90 min). SAEs were rare (0.6%), and the frequency of all safety events decreased over the treatment course. Little impact of infusion duration on safety outcomes was observed: IARs and AEs were numerically more common when infusion duration was ≥ 90 min compared to < 90 min (IARs: 2.0% vs 0.9%; AEs: 2.9% vs 1.4%), while the rate of SAEs was similar (0.4% vs 0.5%). IAR, AE, and SAE frequencies decreased significantly with increasing infusion rates, and this trend was consistent in patients < 30 kg. Safety events tended to be less frequent in patients < 30 kg vs those ≥ 30 kg (IARs: 1.8% vs 2.1%; AEs: 2.3% vs 3.6%; SAEs: 0.0% vs 0.6%), although the differences were not statistically significant. IARs occurred in < 1% of all infusions in the < 30 kg group, 84% of which were < 90 min. More anti-agalsidase beta antibody-positive patients experienced IARs (41.9% vs 30.7%; P = 0.0445) and AEs (61.1% vs 49.3%; P = 0.0497) vs antibody-negative patients; however, there was no significant difference in the frequency of SAEs. In patients with available data, no changes in antibody status were observed after infusion durations were reduced to < 90 min. CONCLUSIONS: The results of this post-hoc analysis demonstrated no significant impact of infusion duration on safety outcomes, and no significant difference in outcomes between patients of different weights. These findings suggest that infusion times in patients who are tolerating treatment can, with careful monitoring, be gradually decreased.

Characterization of cellular phenotypes in neurons derived from induced pluripotent stem cells of male patients with Fabry disease.

Fabry disease (FD) is an X-linked inherited lysosomal metabolism disorder in which globotriaosylceramide (Gb3) accumulates in various organs resulting from a deficiency in alpha-galactosidase A. The clinical features of FD include progressive impairments of the renal, cardiac, and peripheral nervous systems. In addition, patients with FD often develop neuropsychiatric symptoms, such as depression and dementia, which are believed to be induced by the cellular injury of cerebrovascular and partially neuronal cells due to Gb3 accumulation. Although the analysis of autopsy brain tissue from patients with FD showed no accumulation of Gb3, abnormal deposits of Gb3 were found in the neurons of several brain areas, including the hippocampus. Therefore, in this study, we generated induced pluripotent stem cells (iPSCs) from patients with FD and differentiated them into neuronal cells to investigate pathological and biological changes in the neurons of FD. Neural stem cells (NSCs) and neurons were successfully differentiated from the iPSCs we generated; however, cellular damage and morphological changes were not found in these cells. Immunostaining revealed no Gb3 accumulation in NSCs and neurons. Transmission electron microscopy did not reveal any zebra body-like structures or inclusion bodies, which are characteristic of FD. These results indicated that neuronal cells derived from FD-iPSCs exhibited normal morphology and no Gb3 accumulation. It is likely that more in vivo environment-like cultures are needed for iPSC-derived neurons to reproduce disease-specific features.

Development of a Highly Sensitive and Rapid Liquid Chromatography-Tandem Mass Spectrometric Method Using a Basic Mobile Phase Additive to Determine the Characteristics of the Urinary Metabolites for Niemann-Pick Disease Type C.

As Niemann-Pick disease type C (NPC) is difficult to diagnose owing to its various clinical symptoms; biomarker tests have been developed. Previously, we revealed urinary sulfated cholesterol metabolites as noninvasive biomarkers for NPC. However, LC/tandem mass spectrometry (LC/MS/MS) requires long separation time and large urine volumes. Recently, a basic mobile phase was reported to increase the MS intensity. Thus, we developed a highly sensitive and rapid LC/MS/MS method for analyzing urinary cholesterol metabolites using a basic mobile phase additive. 3ß-Sulfooxy-7ß-N-acetylglucosaminyl-5-cholenic acid, its glycine and taurine conjugates, 3ß-sulfooxy-7ß-hydroxy-5-cholenic acid, and 7-oxo form were measured, with selected reaction monitoring in negative ion mode. Oasis HLB and L-column 3 were used for column-switching LC/MS/MS and urine diluted 10-fold was employed as the sample. After trapping, gradient separation was performed using solutions containing 1% (v/v) ammonium solution. On average, a 16-fold increase in peak areas was observed compared to that obtained at pH 5.5 with the mobile phases. Although the previous method needed 60 min for separation from interference peaks, we succeeded to separate them in 7 min with optimized LC condition. Further, all compounds showed good linearity from 0.3-1000 ng/mL, with satisfactory intra- and inter-day reproducibility. The developed method was applied to the urinalysis of healthy participants and NPC patients. Overall, the concentrations of metabolites correlated with those obtained using the previous method. Therefore, we succeeded to increasing MS intensity and shorten LC running time; and the method is useful for the noninvasive diagnostic screening of patients with NPC.

A survey on the patient journey in Fabry disease in Japan.

Background: Fabry disease (FD) is a rare X-linked lysosomal storage disease caused by a deficiency in α-galactosidase that is frequently diagnosed late after disease onset. While previous studies have focused on the multisystem manifestations that can lead to delayed or incorrect diagnosis and management, none have investigated the entire patient journey, and few have examined the patient's disease experience. Objective: To investigate the path to diagnosis from disease onset, and the impact of the disease on daily life, among individuals with FD in Japan. Methods: A nationwide survey of patients with FD receiving enzyme replacement therapy (ERT) was conducted between March 27 and June 11, 2018. Participants were recruited via patient support groups or physicians. Respondents completed a questionnaire eliciting information on sociodemographic status, self-perceived health status, initial and current clinical manifestations, the process of diagnosis, and impact on their life. Responses were analyzed descriptively. Results: Data from 40 respondents were analyzed (17 males and 23 females; 77.5% aged ≥30 years). Mean ERT duration was 7.7 years. Mean time from disease onset to diagnosis was 18.7 years (16.7 years [males] vs 20.3 years [females]). The final diagnosis was made most commonly by pediatricians (38%). Forty percent of respondents felt relieved and 30% felt anxious when diagnosed, and when initiating ERT, 48% felt more positive about their daily life. Nevertheless, 85% reported that treatment affected their lives/work, and most (73%) experienced difficulties in their relationships with others. Conclusion: Efforts are needed to achieve early diagnosis of patients with FD in Japan, to improve clinician awareness, and improve the psychosocial issues associated with FD.

The role of native T1 values on the evaluation of cardiac manifestation in Japanese Fabry disease patients.

Aims: T1 mapping in cardiac magnetic resonance imaging enables us to distinguish various myocardial diseases showing left ventricular hypertrophy. Fabry disease is a lysosomal storage disorder causing the accumulation of glycosphingolipids into various organs, including the heart, which can be detected by native T1 values in T1 mapping. However, there is no report for the systematic evaluation of native T1 values in Fabry disease in Japan. Methods and results: We analyzed native T1 values of 30 Fabry disease patients (14 males and 16 females) obtained by 3-T cardiac magnetic resonance imaging. Averaged T1 values were significantly lower in male patients (septal T1: 1149.5 ± 63.3 ms; total T1: 1145.1 ± 59.5 ms) than in female patients (septal T1: 1210.5 ± 45.5 ms; total T1: 1198.8 ± 51.8 ms) (p < 0.01). We compared the native T1 values of Fabry disease patients with those obtained from 15 hypertrophic cardiomyopathy patients (9 males and 6 females). Native T1 values effectively differentiate Fabry disease from hypertrophic cardiomyopathy (septal T1: sensitivity 93.3% and specificity 80.0%; total T1: sensitivity 86.7% and specificity 73.3%). In addition, native T1 values had a significant negative correlation with the left ventricular mass index in male patients at the pre-hypertrophic stage (p < 0.05). In male and female patients without late-gadolinium enhancement, native T1 values also had a significant negative correlation with the left ventricular mass index (p < 0.05). Conclusion: These results suggest that native T1 values can be used to discriminate Fabry disease from hypertrophic cardiomyopathy and can reflect the accumulation of glycosphingolipids in cardiomyocytes.

Generation and characterization of motor neuron progenitors and motor neurons using metachromatic leukodystrophy-induced pluripotent stem cells.

The pathological consequences leading to primary storage, autophagy impairment, impaired mitochondrial dynamics, and endoplasmic reticulum (ER) stress on neural cell dysfunction and apoptosis in metachromatic leukodystrophy (MLD) have been poorly elucidated. In the present study, we generated 2 cell lines of patient-specific-induced pluripotent stem cells (iPSCs) and modeled the progression of pathological events during the differentiation of iPSCs to motor neuron progenitors (MNPs) and mature motor neurons (MNs). The iPS cells were generated from two late-infantile MLD patient-derived skin fibroblasts using electroporation or the Sendai virus. Olig2+ MNPs were generated from both iPSC lines using a combination of small molecules in a chemically defined neural medium. Furthermore, the MNPs could be differentiated into mature MNs, which was confirmed by RT-PCR and MN markers, including SMI32 and ChAT. The population of MNs was approximately 50% under the culture conditions. Pathological observation of MLD patient-derived iPSCs revealed lysosomal accumulation and impaired autophagy. In addition, both MNPs and MNs derived from MLD-iPSCs showed increased lysosomal accumulation, dysfunctional autophagy, impaired mitophagy, endoplasmic reticulum (ER) stress or unfolded protein response (UPR) activation, and premature cellular death.

Enzyme Replacement Therapy with Pabinafusp Alfa for Neuronopathic Mucopolysaccharidosis II: An Integrated Analysis of Preclinical and Clinical Data.

Enzyme replacement therapy (ERT) improves somatic manifestations in mucopolysaccharidoses (MPS). However, because intravenously administered enzymes cannot cross the blood-brain barrier (BBB), ERT is ineffective against the progressive neurodegeneration and resultant severe central nervous system (CNS) symptoms observed in patients with neuronopathic MPS. Attempts to surmount this problem have been made with intrathecal and intracerebroventricular ERT in order to achieve CNS effects, but the burdens on patients are inimical to long-term administrations. However, since pabinafusp alfa, a human iduronate-2-sulfatase fused with a BBB-crossing anti-transferrin receptor antibody, showed both central and peripheral efficacy in a mouse model, subsequent clinical trials in a total of 62 patients with MPS-II (Hunter syndrome) in Japan and Brazil substantiated this dual efficacy and provided an acceptable safety profile. To date, pabinafusp alfa is the only approved intravenous ERT that is effective against both the somatic and CNS symptoms of patients with MPS-II. This article summarizes the previously obtained preclinical and clinical evidence related to the use of this drug, presents latest data, and discusses the preclinical, translational, and clinical challenges of evaluating, ameliorating, and preventing neurodegeneration in patients with MPS-II.

A neuropathological cell model derived from Niemann-Pick disease type C patient-specific iPSCs shows disruption of the p62/SQSTM1-KEAP1-NRF2 Axis and impaired formation of neuronal networks.

Niemann-Pick disease type C (NPC) is a rare neurodegenerative disorder caused by a recessive mutation in the NPC1 or NPC2 gene, in which patients exhibit lysosomal accumulation of unesterified cholesterol and glycolipids. Most of the research on NPC has been done in patient-derived skin fibroblasts or mouse models. Therefore, we developed NPC patient neurons derived from induced pluripotent stem cells (iPSCs) to investigate the neuropathological cause of the disease. Although an accumulation of cholesterol and glycolipids, which is characteristic of NPC, was observed in both undifferentiated iPSCs and derived neural stem cells (NSCs), we could not observed the abnormalities in differentiation potential and autophagic activity in such immature cells. However, definite neuropathological features were detected in mature neuronal cells generated from NPC patient-derived iPSCs. Abnormal accumulation of cholesterol and other lipids identified by lipid droplets and number of enlarged lysosomes was more prominent in mature neuronal cells rather than in iPSCs and/or NSCs. Thin-sectioning electron microscopic analysis also demonstrated numerous typical membranous cytoplasmic bodies in mature neuronal cells. Furthermore, TUJ1-positive neurite density was significantly reduced in NPC patient-derived neuronal cells. In addition, disruption of the p62/SQSTM1-KEAP1-NRF2 axis occurred in neurons differentiated from NPC patient-derived iPSCs. These data indicate the impairment of neuronal network formation associated with neurodegeneration in mature neuronal cells derived from patients with NPC.

Prevalence of patients with lysosomal storage disorders and peroxisomal disorders: A nationwide survey in Japan.

INTRODUCTION: Lysosomal storage disorders and peroxisomal disorders are rare diseases caused by the accumulation of substrates of the metabolic pathway within lysosomes and peroxisomes, respectively. Owing to the rarity of these diseases, the prevalence of lysosomal storage disorders and peroxisomal disorders in Japan is unknown. Therefore, we conducted a nationwide survey to estimate the number of patients with lysosomal storage disorders and peroxisomal disorders in Japan. METHODS: A nationwide survey was conducted following the "Manual of nationwide epidemiological survey for understanding patient number and clinical epidemiology of rare diseases (3rd version)". A questionnaire asking for detailed information, such as disease phenotypes and medical history, was created and sent to 504 institutions with doctors who have experience in treating patients with lysosomal storage disorders and peroxisomal disorders. Result A total of 303 completed questionnaires were collected from 504 institutions (response rate: 60.1%). The number of patients was estimated by calculating the rate/frequency of overlap. The estimated number of patients was 1658 (±264.8) for Fabry disease, 72 (±11.3) for mucopolysaccharidosis I, 275 (±49.9) for mucopolysaccharidosis II, 211 (±31.3) for Gaucher disease, 124 (±25.8) for Pompe disease, 83 (±44.3) for metachromatic leukodystrophy, 57 (±9.4) for Niemann-Pick type C, and 262 (±42.3) for adrenoleukodystrophy. In addition the birth prevalence was calculated using the estimated number of patients and birth year data for each disease, and was 1.25 for Fabry disease, 0.09 for mucopolysaccharidosis I, 0.38 for mucopolysaccharidosis II, 0.19 for Gaucher disease, 0.14 for Pompe disease, 0.16 for metachromatic leukodystrophy, 0.16 for Niemann-Pick type C, and 0.20 for adrenoleukodystrophy. DISCUSSION: Among the diseases analyzed, the disease with the highest prevalence was Fabry disease, followed by mucopolysaccharidosis II, adrenoleukodystrophy, Gaucher disease and metachromatic leukodystrophy. In particular, the high prevalence of mucopolysaccharidosis II and Gaucher disease type II was a feature characteristic of Japan. CONCLUSION: We estimated the number of patients with lysosomal storage disorders and peroxisomal disorders in Japan. The details of the age at diagnosis and treatment methods for each disease were clarified, and will be useful for the early diagnosis of these patients and to provide appropriate treatments. Furthermore, our results suggest that supportive care and the development of an environment that can provide optimal medical care is important in the future.

A Phase 2/3 Trial of Pabinafusp Alfa, IDS Fused with Anti-Human Transferrin Receptor Antibody, Targeting Neurodegeneration in MPS-II.

Pabinafusp alfa (JR-141) is a novel enzyme drug that crosses the blood-brain barrier by transcytosis via transferrin receptors. In order to establish its efficacy and safety, a multicenter, single-arm, open-label phase 2/3 clinical trial was conducted in 28 Japanese patients with mucopolysaccharidosis II (MPS-II, Hunter syndrome) by intravenous administrations of 2.0 mg/kg of pabinafusp alfa for 52 weeks. The primary efficacy endpoint was changes in heparan sulfate (HS) concentrations in the cerebrospinal fluid (CSF). Secondary endpoints included assessments of neurocognitive development for central efficacy, and changes in plasma HS and dermatan sulfate (DS) concentrations for peripheral efficacy. HS concentrations in the CSF significantly decreased from baseline to week 52 (p < 0.001), suggesting continuous inhibition of substrate accumulations in the CNS, i.e., hitherto unaddressed progressive neurodegeneration. Evaluations of neurocognitive developments showed positive changes in 21 of the 28 patients. Serum HS and DS concentrations, liver and spleen volumes, and other assessments suggested the peripheral efficacy of pabinafusp alfa was comparable to that of idursulfase. Drug-related adverse events were mild or moderate in severity, transient, and manageable. The results establish delivery across the BBB of pabinafusp alfa as an effective therapeutic for treating both the CNS and peripheral symptoms of patients with MPS-II.

A combination of 7-ketocholesterol, lysosphingomyelin and bile acid-408 to diagnose Niemann-Pick disease type C using LC-MS/MS.

BACKGROUND: Niemann-Pick disease type C (NPC) is an autosomal recessive disorder caused by mutations of NPC1 or NPC2, which encode the proteins that are responsible for intracellular cholesterol trafficking. Loss of this function results in the accumulation of cholesterol-related products, such as oxysterols, sphingolipids, and NPC-related bile acids, which were recently used as biochemical biomarkers for the diagnosis of NPC. Bile acid-408 is a new significant compound we found in Japanese NPC patients, and it likely belongs to the category of bile acids. However, the diagnosis of NPC using a single biomarker is not satisfactory for clinical application because of the high instance of false negatives or positives. Therefore, we proposed an application of NPC diagnosis using a combination of 7-ketocholesterol (7-KC), lysosphingomyelin (lysoSM), bile acid-408 and/or glucosylsphingosine (lysoGL-1). METHODS AND FINDINGS: 7-KC, lysoSM and lysoGL-1 in sera and bile acid-408 in dried blood spots (DBS) were quantified within 17 minutes using tandem mass spectrometry and high-resolution mass spectrometry, respectively. We measured these biomarkers in NPC patients (n = 19), X-linked adrenoleukodystrophy (X-ALD) patients (n = 5), patients with other lysosomal diseases (n = 300), newborns (n = 124) and healthy people (n = 74). Our results showed a promising accuracy (97%) for NPC diagnosis using the combination of 7-KC, lysoSM and bile acid-408. However, contrary to our expectations, lysoGL-1 levels did not present at a significantly greater amount in NPC patients than other patients and negative controls. CONCLUSIONS: The combination of 7-KC, lysoSM and bile acid-408 improves the accuracy of NPC diagnosis and is feasible for mass screening due to its simple sample preparation and measurement. Future research should investigate the chemical structure of bile acid-408 to further facilitate its advantage in diagnosis.

Massive accumulation of globotriaosylceramide in various tissues from a Fabry patient with a high antibody titer against alpha-galactosidase A after 6 years of enzyme replacement therapy.

Fabry disease is an X-linked metabolic disorder due to a pathogenic mutation of the GLA gene. The accumulation of globotriaosylceramide (Gb3) damages multiple organs, including the heart, kidney and nervous system, especially in classical type Fabry disease. Enzyme replacement therapy (ERT) using recombinant alpha-galactosidase A has been shown to remove Gb3 from organs and to improve the prognosis of Fabry disease. We herein report the case of a 67-year-old classical type Fabry patient who had been treated with ERT for 6 years and who continuously showed a high antibody titer against recombinant alpha-galactosidase A during therapy. A post-mortem examination was performed after sudden death. A histological examination revealed the massive accumulation of Gb3 in various organs, even after long term ERT. In addition to the typical pathological findings as reported in tissue biopsy samples, the serious accumulation of Gb3 in the cardiac conduction system and the endocrine system was detected. Since the start of ERT for this patient might be too late to improve organ damage and prognosis, ERT should be started before the appearance of major organ involvement for the effective elimination of Gb3 and changes in the therapeutic strategy might be considered if the patient shows a high antibody titer against recombinant alpha-galactosidase A.

Development of a Diagnostic Screening Strategy for Niemann-Pick Diseases Based on Simultaneous Liquid Chromatography-Tandem Mass Spectrometry Analyses of N-Palmitoyl-O-phosphocholine-serine and Sphingosylphosphorylcholine.

Early diagnosis of Niemann-Pick diseases (NPDs) is important for better prognosis of such diseases. N-Palmitoyl-O-phosphocholine-serine (PPCS) is a new NPD biomarker possessing high sensitivity, and with its combination with sphingosylphosphocholine (SPC) it may be possible to distinguish NPD-C from NPD-A/B. In this study, a rapid liquid chromatography-tandem mass spectrometry (LC-MS/MS) method (method 1) and a validated LC-MS/MS analysis (method 2) of PPCS and SPC were developed, and we have proposed a diagnostic screening strategy for NPDs using a combination of serum PPCS and SPC concentrations. Nexera and API 5000 were used as LC-MS/MS systems. C18 columns with lengths of 10 and 50 mm were used for method 1 and 2, respectively. 2H3-Labeled PPCS and nor-SPC were used as internal standards. Selective reaction monitoring in positive-ion mode was used for MS/MS. Run times of 1.2 and 8 min were set for methods 1 and 2, respectively. In both methods 1 and 2, two analytes showed high linearity in the range of 1-4000 ng/mL. Method 2 provided high accuracy and precision in method validation. Serum concentrations of both analytes were significantly higher in NPD-C patients than those of healthy subjects in both methods. Serum PPCS correlated between methods 1 and 2; however, it was different in the case of SPC. The serum PPCS/SPC ratio was different in healthy subjects, NPD-C, and NPD-A/B. These results suggest that using a combination of the two LC-MS/MS analytical methods for PPCS and SPC is useful for diagnostic screening of NPDs.

Pharmacokinetics and pharmacodynamics of JR-051, a biosimilar of agalsidase beta, in healthy adults and patients with Fabry disease: Phase I and II/III clinical studies.

Fabry disease is a rare X-linked lysosomal disease, in which mutations in the gene encoding α-galactosidase A result in progressive cellular accumulation of globotriaosylceramide (GL-3) in various organs including the skin, kidney, and heart, often leading to life-threatening conditions. Enzyme replacement therapy is currently the standard therapy for the disease, to which two α-galactosidase A formulations have been approved: agalsidase α (Replagal®, Shire) and agalsidase ß (Fabrazyme®, Sanofi). We have recently developed a biosimilar of agalsidase ß, JR-051, and investigated its pharmacokinetics and pharmacodynamics to assess its bioequivalence to agalsidase ß. In a randomized phase I study, healthy adult male volunteers were treated with JR-051 or agalsidase ß and the pharmacokinetics of the drugs were compared. The ratio of geometric means (90% confidence interval [CI]) of the AUC0-24 and Cmax for JR-051 over agalsidase ß were 0.91 (0.8294, 1.0082) and 0.90 (0.7992, 1.0125), respectively. In a 52-week, single-arm, phase II/III study, patients with Fabry disease switched therapy from agalsidase ß to JR-051 to evaluate its pharmacodynamics. The mean (95% CI) plasma GL-3 concentrations at weeks 26 and 52 relative to pre-JR-051 administration were 1.03 (0.91, 1.15) and 0.96 (0.86, 1.06), respectively, which were within the pre-determined bioequivalence acceptance range (0.70, 1.43). The mean (95% CI) plasma globotriaosylsphingosine (lyso-GL-3) concentrations at weeks 26 and 52 relative to pre-JR-051 administration were 1.07 (0.92, 1.23) and 1.13 (1.03, 1.22), respectively. Estimated glomerular filtration rate and left ventricular mass index, as renal and cardiac function indicators, showed no notable changes from baseline throughout the study period, and no new safety concerns were identified. In conclusion, these studies demonstrated bioequivalence of JR-051 to agalsidase ß in terms of its pharmacokinetics and pharmacodynamics. JR-051 offers a potential new treatment option for patients with Fabry disease.

Characteristics of the Electrocardiogram in Japanese Fabry Patients Under Long-Term Enzyme Replacement Therapy.

Objective: An electrocardiogram (ECG) is an important tool for demonstrating cardiac manifestations in various heart diseases. The present study clarified the characteristics of ECG parameters in Japanese Fabry patients under long-term enzyme replacement therapy (ERT). Methods: We analyzed the ECGs of 40 Fabry patients (male, n = 17; female, n = 23) before and after treatment with ERT. To evaluate the atrio-ventricular conduction, the PQ interval, corrected PQ and PQ minus P-wave in lead II (Pend-Q) were calculated. The QRS duration, QTc, Sokolow-Lyon index, and strain pattern were also examined. Results: At the baseline, the shortening of the PQ interval, corrected PQ and Pend-Q was identified in 7.5, 25.0, and 47.5% of cases, respectively. The prolongation of QRS duration and QTc was found in 7.5 and 40.0% of cases, respectively. The strain pattern was mainly identified in female patients, irrespective of left ventricular hypertrophy (LVH). During long-term ERT, the PQ interval, corrected PQ and Pend-Q did not change significantly. The QRS duration was significantly prolonged in both genders, whereas the QTc was significantly prolonged only in male patients. A subgroup analysis revealed that the prolongation of the QRS duration and QTc only occurred in male patients with LVH and only occurred in female patients with the classical type mutation. The prevalence of the strain was significantly increased only in male patients with LVH. Conclusions: These results suggest that the shortening of the Pend-Q is a specific finding in Japanese Fabry patients, and the strain pattern without LVH in female patients can be considered Fabry disease. During long-term ERT, prolongation of the QRS duration and QTc can indicate the progression of myocardial damage in male patients with LVH and in female patients with the classical type mutation.

Clinical findings of gadolinium-enhanced cardiac magnetic resonance in Fabry patients.

BACKGROUND: Fabry disease is one of the causes of left ventricular hypertrophy (LVH) and can be treated with enzyme replacement therapy or pharmacological chaperone therapy. Late gadolinium enhancement (LGE) in cardiac magnetic resonance (CMR) can identify myocardial fibrosis and be used for the stratification in LVH. However, the details of the prevalence and characteristics of LGE in Japanese Fabry patients have not been reported. METHODS: We evaluated myocardial involvement in 26 Fabry patients (10 males, 16 females) using gadolinium-enhanced CMR. LGE areas were analyzed using the previously reported scoring method. Echocardiography was also performed to evaluate the left ventricular function and left ventricular mass. RESULTS: LGE on CMR images was positive in 5 out of 26 patients, and all patients with LGE-positive findings suffered from LVH (2 out of 5 male patients and 3 out of 4 female patients with LVH on echocardiography). LGE was specifically localized at the mid-wall in the infero-lateral area of the left ventricle. LGE-positive patients seemed to be older, and tended to have a larger left ventricular mass index and higher B-type natriuretic peptide level than LGE-negative patients. CONCLUSIONS: These results revealed that specific localization of LGE was present in Fabry patients.

Structural Determination of Lysosphingomyelin-509 and Discovery of Novel Class Lipids from Patients with Niemann-Pick Disease Type C.

Niemann-Pick disease type C (NPC) is an autosomal recessive disorder caused by the mutation of cholesterol-transporting proteins. In addition, early treatment is important for good prognosis of this disease because of the progressive neurodegeneration. However, the diagnosis of this disease is difficult due to a variety of clinical spectrum. Lysosphingomyelin-509, which is one of the most useful biomarkers for NPC, was applied for the rapid and easy detection of NPC. The fact that its chemical structure was unknown until recently implicates the unrevealed pathophysiology and molecular mechanisms of NPC. In this study, we aimed to elucidate the structure of lysosphingomyelin-509 by various mass spectrometric techniques. As our identification strategy, we adopted analytical and organic chemistry approaches to the serum of patients with NPC. Chemical derivatization and hydrogen abstraction dissociation-tandem mass spectrometry were used for the determination of function groups and partial structure, respectively. As a result, we revealed the exact structure of lysosphingomyelin-509 as N-acylated and O-phosphocholine adducted serine. Additionally, we found that a group of metabolites with N-acyl groups were increased considerably in the serum/plasma of patients with NPC as compared to that of other groups using targeted lipidomics analysis. Our techniques were useful for the identification of lysosphingomyelin-509.

Investigation of diagnostic performance of five urinary cholesterol metabolites for Niemann-Pick disease type C.

Niemann-Pick disease type C (NPC) is an autosomal recessive disorder characterized by progressive nervous degeneration. Because of the diversity of clinical symptoms and onset age, the diagnosis of this disease is difficult. Therefore, biomarker tests have attracted significant attention for earlier diagnostics. In this study, we developed a simultaneous analysis method for five urinary conjugated cholesterol metabolites, which are potential diagnostic biomarkers for a rapid, convenient, and noninvasive chemical diagnosis, using LC/MS/MS. By the method, their urinary concentrations were quantified and the NPC diagnostic performances were evaluated. The developed LC/MS/MS method showed high accuracy and satisfied all analytical method validation criteria. When the urine of healthy controls and patients with NPC was analyzed, three of five urinary conjugated cholesterol metabolite concentrations corrected by urinary creatinine were significantly higher in the patients with NPC. As a result of receiver operating characteristics analysis, these urinary metabolites might have excellent diagnostic marker performance. 3ß-Sulfooxy-7ß-hydroxy-5-cholenoic acid showed particularly excellent diagnostic performance with both 100% clinical sensitivity and specificity, suggesting that it is a useful NPC diagnostic marker. The urinary conjugated cholesterol metabolites exhibited high NPC diagnostic marker performance and could be used for NPC diagnosis.