Effects of miglustat therapy on neurological disorder and survival in early-infantile Niemann-Pick disease type C: a national French retrospective study.

BACKGROUND: Niemann-Pick disease type C (NP-C) is a rare neurovisceral lysosomal lipid storage disease characterized by progressive neurodegeneration and premature death. While miglustat can stabilize neurological manifestations in later onset forms of NP-C, its efficacy in the early-infantile neurological form has not been demonstrated. In this observational retrospective study, we compared long-term neurodevelopmental outcome and survival between an untreated and a treated group of early infantile NP-C patients. METHODS: Data available on all NP-C patients with early infantile neurological onset diagnosed in France between 1990 and 2013 were compiled. Patients with incomplete data or who had died from a systemic perinatal, rapidly fatal form were excluded. RESULTS: Ten patients were included in the treated group (year of birth: 2006-2012), and 16 patients in the untreated group [born 1987-2005 (n = 15), 2012 (n = 1)]. The median age at neurological onset was 9 months (5-18) in the treated group, and 12 months (3-18) in the untreated group (p = 0.22). Miglustat therapy was started at a median age of 24.5 months (9-29) and median duration was 30 months (11-56). Gastrointestinal adverse events were reported in 7/10 patients on miglustat. All patients developed loss of psychomotor acquisitions or additional neurological symptoms despite miglustat therapy. The ages of developmental milestones and neurological involvement did not significantly differ between the two groups. Four patients in the untreated group were lost to follow up. The 22 remaining patients had died by the end of the study and no patient survived beyond the age of 7.4 years. The median survival age was 4.42 years in the untreated group and 5.56 years in the treated group; the Kaplan-Meier survival curves were not significantly different (log-rank test: p = 0.11). CONCLUSIONS: Miglustat allowed no significant long-term neurodevelopmental improvement nor significant increase of survival in patients with early infantile NP-C.

Current advancements in therapy for Niemann-Pick disease: progress and pitfalls.

INTRODUCTION: Niemann-Pick disease type C (NPC) is a rare, autosomal recessive, lysosomal storage disorder. To combat the progressive neurodegeneration in NPC, disease-modifying treatment needs to be introduced early in the course of the disease. The only approved, disease-modifying treatment is a substrate-reduction treatment, miglustat. Given miglustat's limited efficacy, new compounds are under development, including gene therapy; however, many are still far from clinical use. Moreover, the phenotypic heterogeneity and variable course of the disease can impede the development and approval of new agents. AREAS COVERED: Here, we offer an expert review of these therapeutic candidates, with a broad scope not only on the main pharmacotherapies, but also on experimental approaches, gene therapies, and symptomatic strategies. The National Institute of Health (NIH) database PubMed has been searched for the combination of the words 'Niemann-Pick type C'+ 'treatment' or 'therapy' or 'trial.' The website clinicaltrials.gov has also been consulted. EXPERT OPINION: We conclude a combination of treatment strategies should be sought, with a holistic approach, to improve the quality of life of affected individuals and their families.

Beneficial in vitro effect of N-acetylcysteine and coenzyme Q10 on DNA damage in neurodegenerative Niemann-Pick type C 1 disease: preliminary results.

Niemann-Pick type C1 (NP-C1) is a lysosomal storage disease (LSD) caused by mutations in NPC1 gene that lead to defective synthesis of the respective lysosomal transporter protein and cholesterol accumulation in late endosomes/lysosomes (LE/L) compartments, as well as glycosphingolipids GM2 and GM3 in the central nervous system (CNS). Clinical presentation varies according to the age of onset and includes visceral and neurological symptoms, such as hepatosplenomegaly and psychiatric disorders. Studies have been associating the pathophysiology of NP-C1 with oxidative damage to lipids and proteins, as well as evaluating the benefits of adjuvant therapy with antioxidants for this disease. In this work, we evaluated the DNA damage in fibroblasts culture from patients with NP-C1 treated with miglustat, as well as the in vitro effect of the antioxidant compounds N-acetylcysteine (NAC) and Coenzyme Q10 (CoQ10), using the alkaline comet assay. Our preliminary results demonstrate that NP-C1 patients have increased DNA damage compared to healthy individuals and that the treatments with antioxidants can mitigate it. DNA damage may be due to an increase in reactive species since it has been described that NP-C1 patients have increased peripheral markers of damage to other biomolecules. Our study suggests that NP-C1 patients could benefit from the use of adjuvant therapy with NAC and CoQ10, which should be better evaluated in a future clinical trial.

Cost-effectiveness of miglustat versus symptomatic therapy of Niemann-Pick disease type C.

BACKGROUND: Niemann-Pick disease type C (NP-C) is a progressive neurodegenerative disorder with early infantile (< 2 years), late infantile (2-6 years), juvenile (7-15 years) and adolescent (> 15 years) onset. The mainstay of therapy for NP-C patients with neurological symptoms is miglustat, a drug that may modify the course of the disease. AIM: Our aim was to evaluate the cost-effectiveness of miglustat in comparison to symptomatic therapy in patients with NP-C in the socio-economic settings of the Republic of Serbia, an upper-middle-income European economy. METHOD: The perspective of the Serbian Republic Health Insurance Fund was chosen for this study, and the time horizon was eighty years. The main outcomes of the study were quality-adjusted life years gained with miglustat and comparator, and direct costs of treatment. The study was conducted through the generation and simulation of the Discrete-Event Simulation model. The model results were obtained after Monte Carlo microsimulation of a sample with 1000 virtual patients. RESULTS: Treatment with miglustat was not cost-effective when compared with symptomatic therapy and was associated with negative values of net monetary benefit regardless of the onset of neurological manifestations (- 110,447,627.00 ± 701,614.00 RSD, - 343,871,695.00 ± 2,577,441.00 RSD, - 1,397,908,502.00 ± 23,084,235.00 RSD and - 2,953,680,879.00 ± 33,297,412.00 RSD) for early infantile, late infantile, juvenile and adolescent cohorts, respectively). CONCLUSION: When traditional pharmacoeconomic evaluation is employed, miglustat is not a cost-effective option in comparison to symptomatic therapy for the treatment of NP-C. However, given the proven efficacy of miglustat, there is a need to find ways to make this drug available to all patients with NP-C.

Organ Weights in NPC1 Mutant Mice Partly Normalized by Various Pharmacological Treatment Approaches.

Niemann-Pick Type C1 (NPC1, MIM 257220) is a rare, progressive, lethal, inherited autosomal-recessive endolysosomal storage disease caused by mutations in the NPC1 leading to intracellular lipid storage. We analyzed mostly not jet known alterations of the weights of 14 different organs in the BALB/cNctr-Npc1m1N/-J Jackson Npc1 mice in female and male Npc1+/+ and Npc1-/- mice under various treatment strategies. Mice were treated with (i) no therapy, (ii) vehicle injection, (iii) a combination of miglustat, allopregnanolone, and 2-hydroxypropyl-ß-cyclodextrin (HPßCD), (iv) miglustat, and (v) HPßCD alone starting at P7 and repeated weekly throughout life. The 12 respective male and female wild-type mice groups were evaluated in parallel. In total, 351 mice (176 Npc1+/+, 175 Npc1-/-) were dissected at P65. In both sexes, the body weights of None and Sham Npc1-/- mice were lower than those of respective Npc1+/+ mice. The influence of the Npc1 mutation and/or sex on the weights of various organs, however, differed considerably. In males, Npc1+/+ and Npc1-/- mice had comparable absolute weights of lungs, spleen, and adrenal glands. In Npc1-/- mice, smaller weights of hearts, livers, kidneys, testes, vesicular, and scent glands were found. In female Npc1-/- mice, ovaries, and uteri were significantly smaller. In Npc1-/- mice, relative organ weights, i.e., normalized with body weights, were sex-specifically altered to different extents by the different therapies. The combination of miglustat, allopregnanolone, and the sterol chelator HPßCD partly normalized the weights of more organs than miglustat or HPßCD mono-therapies.

Possible genotype-phenotype correlations in Niemann-Pick type C patients and miglustat treatment.

BACKGROUND AND PURPOSE: Niemann-Pick type C is a rare lysosomal storage disease caused by impaired intracellular cholesterol transport. The autosomal recessive disease is caused by mutations in NPC1 or NPC2 genes. METHODS: Clinical-laboratory features, genotype-phenotype correlation and miglustat treatment response of our patients diagnosed with early infantile Niemann-Pick type C were evaluated. RESULTS: In this article, four Niemann-Pick type C patients diagnosed in the early infantile period are presented. Common features of our patients were hepatomegaly, splenomegaly, cholestasis and retardation in motor development. Patients 1 and 2 are twins, with homozygous mutation c.2776G>A p.(Ala926Thr) in NPC1 gene and severe lung involvement. Lung involvement, which is mostly associated with NPC2 gene mutation in the literature, was severe in our patients and they died early. In patients 3 and 4, there were respectively c.2972del p.(Gln991Argfs*6) mutation in NPC1 gene and c.133C>T p.(Gln45*) homozygous mutation in NPC2 gene. In these two patients, improvement in neurological findings were observed with treatment of miglustat. CONCLUSION: In our twin patients, severe lung involvement was observed. Two of our four early infantile Niemann-Pick type C patients exhibited neurological gains with miglustat treatment.

Gender-Specific Effects of Two Treatment Strategies in a Mouse Model of Niemann-Pick Disease Type C1.

In a mouse model of Niemann-Pick disease type C1 (NPC1), a combination therapy (COMBI) of miglustat (MIGLU), the neurosteroid allopregnanolone (ALLO) and the cyclic oligosaccharide 2-hydroxypropyl-ß-cyclodextrin (HPßCD) has previously resulted in, among other things, significantly improved motor function. The present study was designed to compare the therapeutic effects of the COMBI therapy with that of MIGLU or HPßCD alone on body and brain weight and the behavior of NPC1-/- mice in a larger cohort, with special reference to gender differences. A total of 117 NPC1-/- and 123 NPC1+/+ mice underwent either COMBI, MIGLU only, HPßCD only, or vehicle treatment (Sham), or received no treatment at all (None). In male and female NPC1-/- mice, all treatments led to decreased loss of body weight and, partly, brain weight. Concerning motor coordination, as revealed by the accelerod test, male NPC1-/- mice benefited from COMBI treatment, whereas female mice benefited from COMBI, MIGLU, and HPßCD treatment. As seen in the open field test, the reduced locomotor activity of male and female NPC1-/- mice was not significantly ameliorated in either treatment group. Our results suggest that in NPC1-/- mice, each drug treatment scheme had a beneficial effect on at least some of the parameters evaluated compared with Sham-treated mice. Only in COMBI-treated male and female NPC+/+ mice were drug effects seen in reduced body and brain weights. Upon COMBI treatment, the increased dosage of drugs necessary for anesthesia in Sham-treated male and female NPC1-/- mice was almost completely reduced only in the female groups.

Association of Miglustat With Swallowing Outcomes in Niemann-Pick Disease, Type C1.

Importance: Niemann-Pick disease, type C1 (NPC1) is a progressive neurovisceral disease with no US Food and Drug Administration-approved therapy. Miglustat, a drug used off-label in the United States for the treatment of NPC1, appears to stabilize neurologic disease progression. Several prospective trials suggest that miglustat stabilizes oropharyngeal swallowing function; however, its effect on dysphagia and aspiration risk has not been demonstrated instrumentally. Objective: To determine if miglustat therapy is associated with stabilized swallowing dysfunction in individuals with NPC1. Design, Setting, and Participants: Patients with confirmed NPC1 diagnoses were evaluated in a single-center cohort study of NPC1 from April 1997 to November 2019. Longitudinal data from individuals with neurologic disease onset prior to age 15 years were analyzed. The study population was divided into those with neurologic disease onset in early childhood (age <6 years) and late childhood (age ≥6 years and <15 years). Analysis began September 2019. Exposures: Oral miglustat at baseline and at follow-up. Main Outcomes and Measures: Oropharyngeal swallowing function was assessed with videofluoroscopic swallowing studies. Overall swallowing ability and aspiration risk were evaluated using the American Speech-Language-Hearing Association National Outcome Measurement System swallowing domain and an adapted Rosenbek aspiration-penetration scale, respectively. Results: Overall, 50 participants were evaluated at baseline (median [interquartile range] age, 9.4 [3.4-16.4] years; 26 [52%] female). The median (interquartile range) duration of follow-up was 3.0 (1.1-4.4) years. Miglustat use was associated with decreased odds of worse American Speech-Language-Hearing Association National Outcome Measurement System swallowing domain outcomes in all 3 subsets (overall: odds ratio [OR], 0.09 [95% CI, 0.02-0.36); P < .001; early childhood: OR, 0.17 [95% CI, 0.04-0.67]; P = .01; late childhood: OR, 0.05 [95% CI, 0.01-0.29]; P = .001). Miglustat use was associated with decreased odds of worse Rosenbek aspiration-penetration scale outcomes in the overall cohort (OR, 0.28 [95% CI, 0.08-0.95]; P = .04) but not in each subgroup (early childhood: OR, 0.27 [95% CI, 0.06-1.22]; P = .09; late childhood: OR, 0.38 [95% CI, 0.06-2.33]; P = .29). Conclusions and Relevance: These data suggest that miglustat use is associated with stabilized swallowing function and reduced aspiration risk in NPC1, thus supporting its use in this population. In addition, these data demonstrate that a quantification of swallowing dysfunction can be used as a clinically relevant, functional outcome measure in future therapeutic trials in NPC1.

Identification of Brain-Specific Treatment Effects in NPC1 Disease by Focusing on Cellular and Molecular Changes of Sphingosine-1-Phosphate Metabolism.

Niemann-Pick type C1 (NPC1) is a lysosomal storage disorder, inherited as an autosomal-recessive trait. Mutations in the Npc1 gene result in malfunction of the NPC1 protein, leading to an accumulation of unesterified cholesterol and glycosphingolipids. Beside visceral symptoms like hepatosplenomegaly, severe neurological symptoms such as ataxia occur. Here, we analyzed the sphingosine-1-phosphate (S1P)/S1P receptor (S1PR) axis in different brain regions of Npc1-/- mice and evaluated specific effects of treatment with 2-hydroxypropyl-ß-cyclodextrin (HPßCD) together with the iminosugar miglustat. Using high-performance thin-layer chromatography (HPTLC), mass spectrometry, quantitative real-time PCR (qRT-PCR) and western blot analyses, we studied lipid metabolism in an NPC1 mouse model and human skin fibroblasts. Lipid analyses showed disrupted S1P metabolism in Npc1-/- mice in all brain regions, together with distinct changes in S1pr3/S1PR3 and S1pr5/S1PR5 expression. Brains of Npc1-/- mice showed only weak treatment effects. However, side effects of the treatment were observed in Npc1+/+ mice. The S1P/S1PR axis seems to be involved in NPC1 pathology, showing only weak treatment effects in mouse brain. S1pr expression appears to be affected in human fibroblasts, induced pluripotent stem cells (iPSCs)-derived neural progenitor and neuronal differentiated cells. Nevertheless, treatment-induced side effects make examination of further treatment strategies indispensable.

Long-term survival outcomes of patients with Niemann-Pick disease type C receiving miglustat treatment: A large retrospective observational study.

Miglustat has been indicated for the treatment of Niemann-Pick disease type C (NP-C) since 2009. The aim of this observational study was to assess the effect of miglustat on long-term survival of patients with NP-C. Data for 789 patients from five large national cohorts and from the NPC Registry were collected and combined. Miglustat-treated and untreated patients overall and within sub-groups according to age-at-neurological-onset, that is, early infantile-onset (<2 years), late infantile-onset (2 to <6 years), juvenile-onset (6 to <15 years), and adolescent/adult-onset (≥15 years) were analysed and compared. Survival was analysed from the time of first neurological manifestation (Neurological onset group, comprising 669 patients) and from diagnosis (Diagnosis group, comprising 590 patients) using a Cox proportional hazard model adjusted for various covariates. Overall, 384 (57.4%) patients in the Neurological onset group and 329 (55.8%) in the Diagnosis group were treated with miglustat. Miglustat treatment was associated with a significant reduction in risk of mortality in both groups (entire Neurological onset group, Hazard ratio [HR] = 0.51; entire Diagnosis group, HR = 0.44; both P < .001). The effect was observed consistently in all age-at-neurological-onset sub-groups (HRs = 0.3 to 0.7) and was statistically significant for late infantile-onset patients in both groups (Neurological onset group, HR = 0.36, P < .05; Diagnosis group, HR = 0.32, P < .01), and juvenile-onset patients in the Diagnosis group only (HR = 0.30, P < .05). Despite the limitations of the data that urge cautious interpretation, the findings are consistent with a beneficial effect of miglustat on survival in patients with NP-C.

Dietary plant stanol ester supplementation reduces peripheral symptoms in a mouse model of Niemann-Pick type C1 disease.

Niemann-Pick type C (NPC)1 disease is a rare genetic condition in which the function of the lysosomal cholesterol transporter NPC1 protein is impaired. Consequently, sphingolipids and cholesterol accumulate in lysosomes of all tissues, triggering a cascade of pathological events that culminate in severe systemic and neurological symptoms. Lysosomal cholesterol accumulation is also a key factor in the development of atherosclerosis and NASH. In these two metabolic diseases, the administration of plant stanol esters has been shown to ameliorate cellular cholesterol accumulation and inflammation. Given the overlap of pathological mechanisms among atherosclerosis, NASH, and NPC1 disease, we sought to investigate whether dietary supplementation with plant stanol esters improves the peripheral features of NPC1 disease. To this end, we used an NPC1 murine model featuring a Npc1-null allele (Npc1nih ), creating a dysfunctional NPC1 protein. Npc1nih mice were fed a 2% or 6% plant stanol ester-enriched diet over the course of 5 weeks. During this period, hepatic and blood lipid and inflammatory profiles were assessed. Npc1nih mice fed the plant stanol-enriched diet exhibited lower hepatic cholesterol accumulation, damage, and inflammation than regular chow-fed Npc1nih mice. Moreover, plant stanol consumption shifted circulating T-cells and monocytes in particular toward an anti-inflammatory profile. Overall, these effects were stronger following dietary supplementation with 6% stanols, suggesting a dose-dependent effect. The findings of our study highlight the potential use of plant stanols as an affordable complementary means to ameliorate disorders in hepatic and blood lipid metabolism and reduce inflammation in NPC1 disease.

Treatment outcomes following continuous miglustat therapy in patients with Niemann-Pick disease Type C: a final report of the NPC Registry.

BACKGROUND: Niemann-Pick disease Type C (NP-C) is a rare, progressive neurodegenerative disorder characterized by progressive neurodegeneration and premature death. We report data at closure of the NPC Registry that describes the natural history, disease course and treatment experience of NP-C patients in a real-world setting. METHODS: The NPC Registry was a prospective observational cohort study that ran between September 2009 and October 2017. Patients with a confirmed diagnosis of NP-C were enrolled regardless of treatment status. All patients underwent clinical assessments and medical care as determined by their physicians; data were collected through a secure internet-based portal. RESULTS: At closure on October 19, 2017, 472 patients from 22 countries were enrolled in the NPC Registry. Mean (standard deviation) age at enrollment was 21.2 (15.0) years, and 51.9% of patients were male. First neurological symptom onset occurred during the early-infantile (< 2 years), late-infantile (2 to < 6 years), juvenile (6 to < 15 years), or adolescent/adult (≥ 15 years) periods in 13.5, 25.6, 31.8, and 29.1% of cases, respectively. The most frequent neurological manifestations prior to enrollment included ataxia (67.9%), vertical supranuclear gaze palsy (67.4%), dysarthria (64.7%), cognitive impairment (62.7%), dysphagia (49.1%), and dystonia (40.2%). During infancy, splenomegaly and hepatomegaly were frequent (n = 199/398 [50%] and n = 147/397 [37.0%], respectively) and persisted in most affected patients. Of the 472 enrolled patients, 241 were continuously treated with miglustat during the NPC Registry observation period, of whom 172 of these 241 patients were treated continuously for ≥12 months. A composite disability score that assesses impairment of ambulation, manipulation, language, and swallowing was highest in the early-infantile population and lowest in the adolescent/adult population. Among the continuous miglustat therapy population, 70.5% of patients had improved or had stable disease (at least 3 of the 4 domains having a decreased or unchanged score between enrollment and last follow-up). The NPC Registry did not identify any new safety signals associated with miglustat therapy. CONCLUSIONS: The profiles of clinical manifestations in the final NPC Registry dataset agreed with previous clinical descriptions. Miglustat therapy was associated with a stabilization of neurological manifestations in most patients. The safety and tolerability of miglustat therapy was consistent with previous reports.

Mechanistic convergence and shared therapeutic targets in Niemann-Pick disease.

Niemann-Pick disease type C (NPC) and Tangier disease are genetically and clinically distinct rare inborn errors of metabolism. NPC is caused by defects in either NPC1 or NPC2; whereas Tangier disease is caused by a defect in ABCA1. Tangier disease is currently without therapy, whereas NPC can be treated with miglustat, a small molecule inhibitor of glycosphingolipid biosynthesis that slows the neurological course of the disease. When a Tangier disease patient was misdiagnosed with NPC and treated with miglustat, her symptoms improved. This prompted us to consider whether there is mechanistic convergence between these two apparently unrelated rare inherited metabolic diseases. In this study, we found that when ABCA1 is defective (Tangier disease) there is secondary inhibition of the NPC disease pathway, linking these two diseases at the level of cellular pathophysiology. In addition, this study further supports the hypothesis that miglustat, as well as other substrate reduction therapies, may be potential therapeutic agents for treating Tangier disease as fibroblasts from multiple Tangier patients were corrected by miglustat treatment.

Niemann-Pick type C: contemporary diagnosis and treatment of a classical disorder.

Niemann-Pick type C is an uncommon neurodegenerative lysosomal storage disorder that can cause a progressive neuropsychiatric syndrome associated with supranuclear vertical gaze palsy and a movement disorder. There have been recent developments in testing that make diagnosis easier and new therapies that aim to stabilise the disease process. A new biochemical test to measure serum cholesterol metabolites supersedes the skin biopsy and is practical and robust. It is treatable with miglustat, a drug that inhibits glycosphingolipid synthesis. We describe a patient, aged 22 years, with juvenile-onset Niemann-Pick type C who presented with seizures and a label of 'cerebral palsy'. We describe the approach to this syndrome in general, and highlight the classical features and red flags that should alert a neurologist to this treatable condition.

Disease characteristics, prognosis and miglustat treatment effects on disease progression in patients with Niemann-Pick disease Type C: an international, multicenter, retrospective chart review.

BACKGROUND: Niemann-Pick disease Type C (NP-C) is a lysosomal lipid storage disorder characterized by progressive neurodegenerative symptomatology. The signs and symptoms of NP-C vary with age at disease onset, and available therapies are directed at alleviating symptoms and stabilizing disease progression. We report the characteristics and factors related to disease progression, and analyze the effect of miglustat treatment on disease progression and patient survival using NP-C disability scales. METHODS: This retrospective, observational chart review included patients with NP-C from five expert NP-C centers. Patient disability scores were recorded using three published NP-C disability scales, and a unified disability scale was developed to allow comparison of data from each scale. Disease progression was represented by scores on the unified NP-C disability scale. Patients were stratified as infantile (< 4 years), juvenile (≥ 4 - < 16 years), and adult (≥ 16 years) based on age at diagnosis, and treated ≥1 year and non-treated/treated < 1 year based on the duration of miglustat treatment. RESULTS: The analysis included 63 patients; the majority (61.9%) were on miglustat therapy for ≥1 year. Ataxia and clumsiness/frequent fall were the most common neurologic symptoms across age groups, whereas, hypotonia and delayed developmental milestones were specific to infantile patients. In both infantile and juvenile patients, visceral signs preceded diagnosis and neurologic signs were noted at or shortly after diagnosis. Adult patients presented with a range of visceral, neurologic, and psychiatric signs in years preceding diagnosis. Patients on miglustat therapy for ≥1 year had a lower mean annual disease progression compared with those untreated/treated < 1 year (1.32 vs 3.54 points/year). A significant reduction in annual disease progression in infantile patients, and a trend towards reduced disease progression in juvenile patients after ≥1 year of miglustat treatment, translated into higher age at last contact or death in these groups. CONCLUSIONS: The type and onset of symptoms varied across age groups and were consistent with descriptions of NP-C within the literature. Miglustat treatment was associated with a reduced rate of disability score worsening in infantile and juvenile patients, both in agreement with increased age at last contact.

Adult Niemann-Pick disease type C in France: clinical phenotypes and long-term miglustat treatment effect.

BACKGROUND: Niemann-Pick disease type C (NP-C) is a neurodegenerative lysosomal lipid storage disease caused by autosomal recessive mutations in the NPC1 or NPC2 genes. The clinical presentation and evolution of NP-C and the effect of miglustat treatment are described in the largest cohort of patients with adolescent/adult-onset NP-C studied to date. METHODS: Observational study based on clinical chart data from adult patients with NP-C (> 18 year old) diagnosed in France between 1990 and 2015. Retrospective data from patients at diagnosis, onset of miglustat therapy (if applicable), and last follow up were analysed. RESULTS: In France, patients with an adolescent-adult neurological form constituted approximately 25% of all NP-C cases diagnosed during the study period. Forty-seven patients (46 with NP-C1 and one with NP-C2; 53% female) were included. Mean ± SD (range) ages at neurological onset and diagnosis were 23.9 ± 12.5 (8-56) years and 34 ± 13.5 (15-65) years, respectively. At presentation, patients mainly had 1) impaired gait due to cerebellar ataxia and/or dystonia, 2) and/or cognitive/behavioural manifestations, 3) and/or psychotic signs. Initially, almost half of patients had only one of the above three neuro-psychiatric manifestations. Vertical supranuclear gaze palsy, usually occurring without patient complaint, was only detected on careful clinical examination and was recorded in most patients (93%) at the time of diagnosis, several years after neurological onset. Thirty-seven patients (79%) received miglustat, among whom seventeen (46%) continued beyond 2 years (at last follow up) to a maximum of 9.8 years. Eight patients (22%) discontinued treatment early due to side effects (n = 3) or perceived lack of efficacy (n = 5).Miglustat treatment duration correlated significantly with reduced neurological worsening (p < 0.001). Treatment for≥2 years was associated with improved patient survival (p = 0.029). Good responses to miglustat were associated with less severe neurological disability at the start of miglustat treatment (p = 0.02). CONCLUSION: The proportion of adolescent/adult-onset NP-C cases diagnosed in France increased 2.5-fold since 2009 compared with the 2000-2008 period due to improved awareness. Adolescent/adult-onset NP-C frequently presented initially with a non-specific isolated neuro-psychiatric manifestation (motor, cognitive or psychotic). Patients with less severe neurological disability responded better to miglustat therapy.

Modeling Niemann-Pick disease type C1 in zebrafish: a robust platform for in vivo screening of candidate therapeutic compounds.

Niemann-Pick disease type C1 (NPC1) is a rare autosomal recessive lysosomal storage disease primarily caused by mutations in NPC1 NPC1 is characterized by abnormal accumulation of unesterified cholesterol and glycolipids in late endosomes and lysosomes. Common signs include neonatal jaundice, hepatosplenomegaly, cerebellar ataxia, seizures and cognitive decline. Both mouse and feline models of NPC1 mimic the disease progression in humans and have been used in preclinical studies of 2-hydroxypropyl-ß-cyclodextrin (2HPßCD; VTS-270), a drug that appeared to slow neurological progression in a Phase 1/2 clinical trial. However, there remains a need to identify additional therapeutic agents. High-throughput drug screens have been useful in identifying potential therapeutic compounds; however, current preclinical testing is time and labor intensive. Thus, development of a high-capacity in vivo platform suitable for screening candidate drugs/compounds would be valuable for compound optimization and prioritizing subsequent in vivo testing. Here, we generated and characterize two zebrafish npc1-null mutants using CRISPR/Cas9-mediated gene targeting. The npc1 mutants model both the early liver and later neurological disease phenotypes of NPC1. LysoTracker staining of npc1 mutant larvae was notable for intense staining of lateral line neuromasts, thus providing a robust in vivo screen for lysosomal storage. As a proof of principle, we were able to show that treatment of the npc1 mutant larvae with 2HPßCD significantly reduced neuromast LysoTracker staining. These data demonstrate the potential value of using this zebrafish NPC1 model for efficient and rapid in vivo optimization and screening of potential therapeutic compounds.This article has an associated First Person interview with the first author of the paper.

High-content screen for modifiers of Niemann-Pick type C disease in patient cells.

Niemann-Pick type C (NPC) disease is a rare lysosomal storage disease caused primarily by mutations in NPC1. NPC1 encodes the lysosomal cholesterol transport protein NPC1. The most common NPC1 mutation is a missense mutation (NPC1I1061T) that causes misfolding and rapid degradation of mutant protein in the endoplasmic reticulum. Cholesterol accumulates in enlarged lysosomes as a result of decreased levels of lysosomal NPC1I1061T protein in patient cells. There is currently no cure or FDA-approved treatment for patients. We sought to identify novel compounds that decrease lysosomal cholesterol storage in NPC1I1061T/I1061T patient fibroblasts using a high-content screen with the cholesterol dye, filipin and the lysosomal marker, LAMP1. A total of 3532 compounds were screened, including 2013 FDA-approved drugs, 327 kinase inhibitors and 760 serum metabolites. Twenty-three hits were identified that decreased both filipin and LAMP1 signals. The majority of hits (16/21) were histone deacetylase (HDAC) inhibitors, a previously described class of modifiers of NPC cholesterol storage. Of the remaining hits, the antimicrobial compound, alexidine dihydrochloride had the most potent lysosomal cholesterol-reducing activity. Subsequent analyses showed that alexidine specifically increased levels of NPC1 transcript and mature protein in both control and NPC patient cells. Although unsuitable for systemic therapy, alexidine represents a unique tool compound for further NPC studies and as a potent inducer of NPC1. Together, these findings confirm the utility of high-content image-based compound screens of NPC1 patient cells and support extending the approach into larger compound collections.

Long-term therapy with miglustat and cognitive decline in the adult form of Niemann-Pick disease type C: a case report.

Niemann-Pick disease type C (NPC) is a recessive lysosomal lipid storage disorder characterized by central nervous system involvement. Miglustat treatment might improve or stabilize neurological manifestations but there is still limited data on the long-term efficacy. The aim of our study was to report a four-year clinical, neuropsychological and electrophysiological follow-up of two sisters under treatment with miglustat. We report data at basal (T0) and after 4 years (T4) of treatment with miglustat from two sisters (P1 and P2) affected by NPC disease. During the follow-up period, P1 was not adherent to treatment. Both patients underwent neurological evaluation, neuropsychological assessment, nerve conduction study and motor (MEP), visual (VEP), somatosensory, and brainstem auditory evoked potentials. In the patient P2, neurological and electrophysiological evaluations at T4 were stable. Instead, the patient P1, with poor adherence to therapy, developed spasticity, psychiatric disturbances, and alterations of MEP and VEP. Neuropsychological examination showed in both patients a worsening of cognitive impairment. Our findings suggest that long-term therapy with miglustat does not arrest cognitive decline; otherwise, it stabilizes other neurological manifestations.

Evaluation of Two Liver Treatment Strategies in a Mouse Model of Niemann-Pick-Disease Type C1.

Niemann-Pick-disease type C1 (NPC1) is an autosomal-recessive cholesterol-storage disorder. Besides other symptoms, NPC1 patients develop liver dysfunction and hepatosplenomegaly. The mechanisms of hepatomegaly and alterations of lipid metabolism-related genes in NPC1 disease are still poorly understood. Here, we used an NPC1 mouse model to study an additive hepatoprotective effect of a combination of 2-hydroxypropyl-ß-cyclodextrin (HPßCD), miglustat and allopregnanolone (combination therapy) with the previously established monotherapy using HPßCD. We examined transgene effects as well as treatment effects on liver morphology and hepatic lipid metabolism, focusing on hepatic cholesterol transporter genes. Livers of Npc1-/- mice showed hepatic cholesterol sequestration with consecutive liver injury, an increase of lipogenetic gene expression, e.g., HMG-CoA, a decrease of lipolytic gene expression, e.g., pparα and acox1, and a decrease of lipid transporter gene expression, e.g., acat1, abca1 and fatp2. Both, combination therapy and monotherapy, led to a reduction of hepatic lipids and an amelioration of NPC1 liver disease symptoms. Monotherapy effects were related to pparα- and acox1-associated lipolysis/ß-oxidation and to fatp2-induced fatty acid transport, whereas the combination therapy additionally increased the cholesterol transport via abca1 and apoE. However, HPßCD monotherapy additionally increased cholesterol synthesis as indicated by a marked increase of the HMG-CoA and srebp-2 mRNA expression, probably as a result of increased hepatocellular proliferation.