Apolipoprotein-mimetic nanodiscs reduce lipid accumulation and improve liver function in acid sphingomyelinase deficiency.

Acid sphingomyelinase deficiency (ASMD) is a severe lipid storage disorder caused by the diminished activity of the acid sphingomyelinase enzyme. ASMD is characterized by the accumulation of sphingomyelin in late endosomes and lysosomes leading to progressive neurological dysfunction and hepatosplenomegaly. Our objective was to investigate the utility of synthetic apolipoprotein A-I (ApoA-I) mimetics designed to act as lipid scavengers for the treatment of ASMD. We determined the lead peptide, 22A, could reduce sphingomyelin accumulation in ASMD patient skin fibroblasts in a dose dependent manner. Intraperitoneal administration of 22A formulated as a synthetic high-density lipoprotein (sHDL) nanodisc mobilized sphingomyelin from peripheral tissues into circulation and improved liver function in a mouse model of ASMD. Together, our data demonstrates that apolipoprotein mimetics could serve as a novel therapeutic strategy for modulating the pathology observed in ASMD.

Healthcare Service Use Patterns Among Patients with Acid Sphingomyelinase Deficiency Type B: A Retrospective US Claims Analysis.

INTRODUCTION: Acid sphingomyelinase deficiency (ASMD) is a rare lysosomal storage disease. Patients with ASMD type B experience multiple morbidities, potentially leading to early mortality. Before the 2022 approval of olipudase alfa for non-neuronopathic ASMD manifestations, only symptom management was offered. Data on healthcare services used by patients with ASMD type B are limited. This analysis used medical claims data to evaluate real-world healthcare service use by patients with ASMD type B in the United States of America (USA). METHODS: The IQVIA Open Claims patient-level database (2010-2019) was cross-examined. Two patient cohorts were identified: the primary analysis cohort, which included patients with at least two claims associated with ASMD type B (ICD-10 code E75.241) and more total claims with ASMD type B than any other ASMD types, and the sensitivity analysis cohort, which included patients with a high probability of having ASMD type B identified using a validated machine-learning algorithm. Claims for ASMD-associated healthcare services were recorded, including outpatient visits, emergency department (ED) visits, and inpatient hospitalizations. RESULTS: The primary analysis cohort included 47 patients; a further 59 patients made up the sensitivity analysis cohort. Patient characteristics and healthcare service use were similar in both cohorts and were consistent with established characteristics of ASMD type B. Overall, 70% of the primary analysis cohort from this study were aged < 18 years, and the liver, spleen, and lungs were the most frequently affected organs. Cognitive, developmental, and/or emotional problems and respiratory/lung disorders caused most outpatient visits; respiratory/lung disorders accounted for most ED visits and hospitalizations. CONCLUSION: This retrospective analysis of medical claims data identified patients with ASMD type B who had characteristics typical of this condition. A machine-learning algorithm detected further cases with a high probability of having ASMD type B. High use of ASMD-related healthcare services and medications was observed in both cohorts.

Acid sphingomyelinase deficiency (ASMD) type B, historically known as Niemann­Pick type B, is a rare illness. People with acid sphingomyelinase deficiency type B experience damage to many organs of the body (such as the liver and lungs), which may lead to early death. Until recently, no treatment has been available, and people were only treated for their symptoms. Now, a treatment called olipudase alfa has been approved in Europe, Japan, and the USA. People with ASMD type B may need lots of tests, surgeries, medications, and physician visits; however, we do not know how often these healthcare services are used. This study used medical claims to find out more about the healthcare services used by people with ASMD type B. To find as many people with ASMD type B as possible, we identified two groups of people. The first group included people with diagnosis codes for ASMD type B, the other group was identified as having a high likelihood of ASMD type B. The people in each group were similar in age and the illnesses/symptoms they had. The liver, spleen, and lungs were the most frequently damaged organs, and most physician visits were for mental, developmental, and/or emotional problems, and breathing or lung diseases. Breathing or lung disease and bleeding problems caused the most emergency department visits and hospitalizations. Overall, the use of healthcare services was high in people with ASMD type B. This study shows the need for specific treatments for people with ASMD.

Clearance of Hepatic Sphingomyelin by Olipudase Alfa Is Associated With Improvement in Lipid Profiles in Acid Sphingomyelinase Deficiency.

Acid sphingomyelinase deficiency (ASMD; Niemann-Pick disease type A and B) is a lysosomal storage disorder characterized by abnormal intracellular sphingomyelin (SM) accumulation. Prominent liver involvement results in hepatomegaly, fibrosis/cirrhosis, abnormal liver chemistries, and a proatherogenic lipid profile. Olipudase alfa (recombinant human ASM) is in clinical development as an investigational enzyme replacement therapy for the non-neurological manifestations of ASMD. In a phase 1b study conducted to evaluate the safety and tolerability of within-patient dose escalation with olipudase alfa, measurement of SM levels in liver biopsies was used as a pharmacodynamic biomarker of substrate burden. Five adult patients with non neuronopathic ASMD received escalating doses of olipudase alfa every 2 weeks for 26 weeks. Liver biopsies obtained at baseline and 26 weeks after treatment were evaluated for SM storage by histomorphometric analysis, biochemistry, and electron microscopy. Biopsies were also assessed for inflammation and fibrosis, and for the association of SM levels with liver volume, liver function tests, and lipid profiles. At baseline, SM storage present in Kupffer cells and hepatocytes ranged from 9.8% to 53.8% of the microscopic field. After 26 weeks of treatment, statistically significant reductions in SM (P<0.0001) measured by morphometry were seen in 4 patients with evaluable liver biopsies. The 26-week biopsy of the fifth patient was insufficient for morphometric quantitation. Posttreatment SM levels ranged from 1.2% to 9.5% of the microscopic field, corresponding to an 84% to 92% relative reduction from baseline. Improvements in liver volume, liver function tests, and lipid profiles were also observed. This study illustrates the utility of SM assessment by liver biopsy as a pharmacodynamic biomarker of disease burden in these patients.