Prevalence of p.G87V and p.Gln298=Variations in LIPA Gene Within Middle Eastern Population Living Around Los Angeles.

Background: The LIPA gene encodes for lysosomal acid lipase (LAL), which catalyzes the hydrolysis of cholesterol esters and triglycerides. Variations in the LIPA gene impair LAL activity, predisposing patients to a rare metabolic disorder called LAL deficiency (LAL-D). The lack of functioning LAL promotes lipid accumulation and subsequent dyslipidemia, which can increase the likelihood of complications in both infants and adults. Although the worldwide prevalence is 1:500,000 births, the frequency in Mizrahi Jewish populations is projected to be as high as 1 in every 4200 births (Valles-Ayoub et al.) based on the LIPA p.G87V variant frequency among 162 individuals. Materials and Methods: This study was conducted to validate the previously reported prevalence of LAL-D in the Mizrahi Jewish population based on the pathogenic LIPA missense variants in exon 4 (c.260G>T; p.G87V) and exon 8 (c.894G>A; p.Gln298=) using a larger cohort of those with Middle Eastern ancestry living around Los Angeles. Among the 1184 individual samples sequenced, 660 self-reported as Mizrahi Jewish, while the remaining 524 came from other Middle Eastern groups labeled as "non-Jewish." Results: Of the 1184 samples, 22 alleles of the exon 4 variant were identified (1.85%), and 2 alleles of the exon 8 variant were identified (0.16%). For the exon 4 variant, 20 of 22 (90.9%) heterozygotes were Mizrahi Jewish, while 2 of 22 (9.09%) heterozygotes were "non-Jewish." For the exon 8 variant, 2 of 2 (100%) heterozygotes were Mizrahi Jewish. This suggests that the prevalence of LAL-D in this population is 1 in 900, which suggests that LAL-D may be 4.6% higher in the Mizrahi Jewish population in previous reports. Conclusion: These findings show increased prevalence of LIPA gene exon 4 variation p.G87V in the Middle East population when compared to the general population, indicating the need for prenatal screening in those of Mizrahi Jewish ancestry.

Wolman disease presenting with hemophagocytic lymphohistiocytosis syndrome and a novel LIPA gene variant: a case report and review of the literature.

BACKGROUND: Wolman disease is a rare disease caused by the absence of functional liposomal acid lipase due to mutations in LIPA gene. It presents with organomegaly, malabsorption, and adrenal calcifications. The presentations can resemble hemophagocytic lymphohistiocytosis, the life threatening hyperinflammatory disorder. Since the disease is very rare, clinicians might not think of it when a patient presents with hemophagocytic lymphohistiocytosis, and the opportunity to treat it properly can be lost, thus leading to demise of the child. CASE PRESENTATION: We present a 4.5-month-old Caucasian boy with fever, icterus, and hepatosplenomegaly who was treated according to presumed hemophagocytic lymphohistiocytosis disease. Wolman disease was diagnosed after the death of the child. There are some case reports in the literature presenting patients with Wolman disease primarily diagnosed as hemophagocytic lymphohistiocytosis, which we discuss in this review. The genetic analysis revealed after his demise was compatible with Wolman disease, introducing a novel mutation in LIPA gene: exon 4: NM_001127605: c. G353A (p.G118D), which converts the glycine amino acid to aspartic acid. CONCLUSIONS: Considering the similarities in presentation of Wolman disease and hemophagocytic lymphohistiocytosis, the patient's life can be saved if special attention is paid to presenting features of a patient with suspected hemophagocytic lymphohistiocytosis, that is special attention to symptoms, findings on physical exams, laboratory values, and radiologic findings, and the proper treatment is urgently initiated. Reporting the novel mutations of Wolman disease can help geneticists interpret the results of their patients' genetic studies appropriately, leading to correct diagnosis and treatment.

First LIPA Mutational Analysis in Egyptian Patients Reveals One Novel Variant: Wolman Disease.

Lysosomal acid lipase (LAL) is a necessary enzyme for the hydrolysis of both triglycerides (TGs) and cholesteryl esters (CEs) in the lysosome. Deficiency of this enzyme encoded by the lipase A (LIPA) gene leads to LAL deficiency (LAL-D). A severe disease subtype of LAL-D is known as Wolman disease (WD), present with diarrhea, hepatosplenomegaly, and adrenal calcification. Untreated patients do not survive more than a year. The aim of this study was to assess the clinical and molecular characterizations of WD patients in Egypt. A total of seven patients (from five unrelated Egyptian families) were screened by targeted next-generation sequencing (NGS), and the co-segregation of causative variants was analyzed using Sanger sequencing. Furthermore, multiple in silico analyses were performed to assess the pathogenicity of the candidate variants. Overall, we identified three diseases causing variants harbored in the LIPA gene. One of these variants is a novel missense variant (NM_000235.4: c.1122 T > G; p. His374Gln), which was classified as a likely pathogenic variant. All variants were predicted to be disease causing using in silico analyses. Our findings expand the spectrum of variants involved in WD which may help to investigate phenotype-genotype correlation and assist genetic counseling. To the best of our knowledge, this is the first clinico-genetic study carried out on Egyptian patients affected with WD.

Recent insights into lysosomal acid lipase deficiency.

Lysosomal acid lipase (LAL) is the sole enzyme known to degrade neutral lipids in the lysosome. Mutations in the LAL-encoding LIPA gene lead to rare lysosomal lipid storage disorders with complete or partial absence of LAL activity. This review discusses the consequences of defective LAL-mediated lipid hydrolysis on cellular lipid homeostasis, epidemiology, and clinical presentation. Early detection of LAL deficiency (LAL-D) is essential for disease management and survival. LAL-D must be considered in patients with dyslipidemia and elevated aminotransferase concentrations of unknown etiology. Enzyme replacement therapy, sometimes in combination with hematopoietic stem cell transplantation (HSCT), is currently the only therapy for LAL-D. New technologies based on mRNA and viral vector gene transfer are recent efforts to provide other effective therapeutic strategies.

Lysosomal Acid Lipase Activity in Non-alcoholic Fatty Liver Disease as a Novel Diagnostic and Therapeutic Target: A Systematic Literature Review of Current Evidence and Future Directions.

Background and aim: Non-alcoholic fatty liver disease (NAFLD) presents with the accumulation of excessive intra-hepatic fat without significant alcohol intake. Multifactorial pathogenesis is reported to be involved. Reduced lysosomal acid lipase (LAL) activity is suggested as one of the novel-involved pathogenic mechanisms. This review summarizes the available evidence on the role of LAL activity in NAFLD pathogenesis. Methods: Four databases namely, PubMed/Medline, Science direct, Cochrane Library, and Google scholar were searched to identify relevant observational records evaluating the role of LAL activity in the pathogenesis of NAFLD. All studies were assessed for their quality by using Newcastle-Ottawa Scale or The Joanna Briggs Institute Critical Appraisal tools for cohort and cross-sectional studies, respectively. The estimates of LAL activity and other clinical outcomes were expressed as mean (SD) and number (%) as presented in the primary studies. Results: A total of nine good quality studies with 1711 patients with NAFLD and 877 controls from different groups (healthy volunteers, alcoholics, cryptogenic cirrhosis, and HCV-positive) were included. From the NAFLD group, 59.55% were males and the overall mean age ranged between the studies from 12.6 ± 8.5 months in pediatrics to 58.90 ± 13.82 years in adults. In the NAFLD group, the LAL activity varied from 0.53 ± 0.08 to 1.3 ± 0.70 (nmol/spot/hr) between the studies which was less than all control groups except cryptogenic cirrhosis patients (0.5 ± 0.15 nmol/spot/hr). Of the other outcomes of interest, ALT, AST, total cholesterol, triglyceride, and LDL cholesterol were found elevated in NAFLD patients than in controls. Conclusion: The current evidence suggests a potential correlation of reduced LAL activity with NAFLD pathogenesis according to its severity. Large-scale studies are recommended, more importantly in patients with NAFLD having no metabolic or genetic involvement. Further LAL can act as a new non-invasive diagnostic biomarker to identify that specific NAFLD subgroup.

Lysosomal acid lipase deficiency: A rare inherited dyslipidemia but potential ubiquitous factor in the development of atherosclerosis and fatty liver disease.

Lysosomal acid lipase (LAL), encoded by the gene LIPA, is the sole neutral lipid hydrolase in lysosomes, responsible for cleavage of cholesteryl esters and triglycerides into their component parts. Inherited forms of complete (Wolman Disease, WD) or partial LAL deficiency (cholesteryl ester storage disease, CESD) are fortunately rare. Recently, LAL has been identified as a cardiovascular risk gene in genome-wide association studies, though the directionality of risk conferred remains controversial. It has also been proposed that the low expression and activity of LAL in arterial smooth muscle cells (SMCs) that occurs inherently in nature is a likely determinant of the propensity of SMCs to form the majority of foam cells in atherosclerotic plaque. LAL also likely plays a potential role in fatty liver disease. This review highlights the nature of LAL gene mutations in WD and CESD, the association of LAL with prediction of cardiovascular risk from genome-wide association studies, the importance of relative LAL deficiency in SMC foam cells, and the need to further interrogate the pathophysiological impact and cell type-specific role of enhancing LAL activity as a novel treatment strategy to reduce the development and induce the regression of ischemic cardiovascular disease and fatty liver.

LC-MS/MS-based enzyme assay for lysosomal acid lipase using dried blood spots.

Lysosomal acid lipase deficiency (LAL-D) (OMIM: 278000) is a lysosomal storage disorder with two distinct disease phenotypes such as Wolman disease and cholesteryl ester storage disorder (CESD), characterized by an accumulation of endocytosed cholesterol in the body. Due to the presence of multiple lipases in DBS, previous studies measured LAL enzyme activity in the presence of Lalistat-2, an established LAL-specific inhibitor (Hamilton J et al Chim Clin Acta (2012) 413:1207-1210). Alternatively, a novel substrate specific for LAL has been reported very recently (Masi S. et al Clin Chem (2018) 64:690-696). In this study, we examined the LAL enzyme activity of a Japanese population with the LAL-specific substrate using liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based enzyme assay whether an affected individual can be identified among this population. To achieve this, we first performed assay validation using LC-MS/MS. Under our experimental setting, typically we obtained LAL enzyme activity for QC High (100% enzyme activity) as 261.9 ± 3.2 µmol/h/L (n = 5) and for QC Low as (5% enzyme activity) as 14.7 ± 0.5 µmol/h/L (n = 5). The percentage of coefficient of variation for interday assay for QC High was 9.6% (n = 4) and for QC Low was 7.9% (n = 4), respectively. Based on these results, we further examined the LAL enzyme activity of control Japanese population and that of affected individuals with Wolman disease and CESD. The averaged enzyme activity for control newborns, Wolman, and CESD was 123.9 ± 53.9 µmol/h/L (n = 131), 6.6 ± 0.9 µmol/h/L (n = 3), and 4.8 ± 0.3 µmol/h/L (n = 3), respectively. These results suggest that an LAL-D-affected individual can be readily identified by enzyme activity using LC-MS/MS-based technique.

Clinical insights from Wolman disease: Evaluating infantile hepatosplenomegaly.

There is a broad differential diagnosis of infantile hepatosplenomegaly, with some etiologies being debilitating and treatable. A structured approach to history, examination, and laboratory and radiographic findings is important in diagnosis. Herein, we present a case of Wolman disease presenting as hepatosplenomegaly in an infant. This case details important learning points to help distinguish the diagnosis of Wolman disease from other conditions with overlapping clinical features, such as hemophagocytic lymphohistiocytosis (HLH). The advent of enzyme replacement therapy has dramatically changed the natural history of Wolman disease, and this child showed remarkable improvement with treatment. This child was later found to have extensive adenopathy with retroperitoneal lymph node biopsy demonstrating diffuse infiltration by lipid-laden macrophages, fatty deposits, cholesterol crystals, and calcifications. Similar to the collection of characteristic cells in other lysosomal storage disorders, we postulate that this is characteristic of underlying Wolman disease. We conclude with a summary of learning points from this presentation on infantile hepatosplenomegaly, pertinent to the geneticist, pediatrician, and pediatric subspecialists.

Wolman's Disease: A Rare Cause of Infantile Cholestasis and Cirrhosis.

Liver cirrhosis in infancy can be secondary to various etiologies such as biliary atresia, familial cholestatic and metabolic disorders. Wolman's disease (WD) is a lysosomal storage disorder caused by the absence of lysosomal acid lipase enzyme activity and a significant association with infantile cholestasis and cirrhosis. We encountered an infant presenting with advanced cirrhosis and decompensation having splenomegaly for which the underlying etiology was found to be WD and the diagnostic clue came from abdominal X-ray showing bilateral adrenal calcifications. The diagnosis was confirmed by genetic analysis. The outcome was poor and died before 6 months of age without enzyme replacement therapy or hematopoietic stem cell transplantation.

Living-Donor Liver Transplantation for Late-Onset Lysosomal Acid Lipase Deficiency.

Late-onset liposomal acid lipase deficiency (LAL deficiency), previously known as Cholesteryl ester storage disease (CESD) is a rare genetic lysosomal storage disorder caused by deficiency of lysosomal acid lipase (LAL) due to mutations in the LIPA gene. LAL deficiency is a systemic disease that leads to the accumulation of fat and inflammation in the liver, premature atherosclerosis and gastrointestinal disease. Most of the patients require liver transplantation due to decompensated cirrhosis. Enzyme replacement therapy has been approved and is available in many countries. Here we describe a 16-year-old patient who was diagnosed to have late-onset LAL deficiency when he presented to us with ESLD. Subsequently, he underwent a living-donor liver transplant (LDLT) successfully. We discuss the ethical dilemmas in considering LDLT for LAL deficiency.

"Why them, why me, why us?" The experiences of parents of children with lysosomal acid lipase deficiency: an interpretative phenomenological analysis study.

BACKGROUND: Lysosomal acid lipase deficiency (LALD) is an ultra-rare, inherited metabolic disease within the category of lysosomal storage disorders, affecting an infant's ability to metabolise cholesterol. Developments in treatment, including Enzyme Replacement Therapy, have proven successful, with some children living for a number of years with treatment, although the future still remains unknown. The aim of this study was to explore the lived experiences of parents of children with LALD. MAIN TEXT: Participants were recruited from across the United Kingdom between 2020 and 2021. Eight parents (five mothers and three fathers) whose child had a confirmed diagnosis of LALD were interviewed. Data collected from the semi-structured interviews were audio-record, transcribed and analysed using Interpretative Phenomenological Analysis (IPA). Three superordinate and nine subordinate themes emerged from the data: (1) Uncertainty-a double-edged sword (plunged into an uncertain world, living life with worry and walking the tightrope of stability), (2) Powerless against a shared battle with LALD (a helpless parent, a joint battle, protection against distress and a vulnerable parent needing help) and 3) Accepting a life with LALD (coming to terms with a diagnosis of LALD and a hidden condition). CONCLUSIONS: The findings of this study highlight that the diagnosis of LALD proves to be a very challenging and emotionally distressing time in parents' lives, with increased uncertainty about what the future will hold for their child. This study signified the importance of healthcare pathways and service provisions to support parents and their children throughout diagnosis and beyond.

Diagnosis, treatment, and follow-up of a case of Wolman disease with hemophagocytic lymphohistiocytosis.

Wolman Disease (WD) is a severe multi-system metabolic disease due to lysosomal acid lipase (LAL) deficiency. We report on a WD infant who developed an unusual hemophagocytic lymphohistiocytosis (HLH) phenotype related to WD treated with sebelipase alfa. A male baby came to our attention at six months of life for respiratory insufficiency and sepsis, abdominal distension, severe hepatosplenomegaly, diarrhea, and severe growth retardation. HLH was diagnosed and treated with intravenous immunoglobulin, steroids, cyclosporine, broad-spectrum antimicrobial therapy, and finally with the anti-IL-6 drug tocilizumab. WD was suspected for the presence of adrenal calcifications and it was confirmed by LAL enzyme activity and by molecular analysis of LIPA. Plasma oxysterols cholestan-3ß,5α,6ß-triol (C-triol), and 7-ketocholesterol (7-KC) were markedly increased. Sebelipase alfa was started with progressive amelioration of biochemical and clinical features. The child died from sepsis, 2 months after sebelipase discontinuation requested by parents. Our case shows the importance of an early diagnosis of WD and confirms the difficulty to reach a diagnosis in the HLH phenotype. Sebelipase alpha is an effective treatment for LAL deficiency, also in children affected by WD. Further data are necessary to confirm the utility of measuring plasma c-triol as a biochemical marker of the disease.

Lysosomal acid lipase deficiency in pediatric patients: a scoping review

Abstract Objective: Lysosomal acid lipase deficiency (LAL-D) is an underdiagnosed autosomal recessive disease with onset between the first years of life and adulthood. Early diagnosis is crucial for effective therapy and long-term survival. The objective of this article is to recognize warning signs among the clinical and laboratory characteristics of LAL-D in pediatric patients through a scope review. Sources: Electronic searches in the Embase, PubMed, Livivo, LILACS, Web of Science, Scopus, Google Scholar, Open Gray, and ProQuest Dissertations and Theses databases. The dataset included observational studies with clinical and laboratory characteristics of infants, children and adolescents diagnosed with lysosomal acid lipase deficiency by enzyme activity testing or analysis of mutations in the lysosomal acid lipase gene (LIPA). The reference selection process was performed in two stages. The references were selected by two authors, and the data were extracted in June 2020. Summary of the findings: The initial search returned 1593 studies, and the final selection included 108 studies from 30 countries encompassing 206 patients, including individuals with Wolman disease and cholesteryl ester storage disease (CESD). The most prevalent manifestations in both spectra of the disease were hepatomegaly, splenomegaly, anemia, dyslipidemia, and elevated transaminases. Conclusions: Vomiting, diarrhea, jaundice, and splenomegaly may be correlated, and may serve as a starting point for investigating LAL-D. Familial lymphohistiocytosis should be part of the differential diagnosis with LAL-D, and all patients undergoing upper gastrointestinal endoscopy should be submitted to intestinal biopsy.

Lysosomal acid lipase deficiency in pediatric patients: a scoping review.

OBJECTIVE: Lysosomal acid lipase deficiency (LAL-D) is an underdiagnosed autosomal recessive disease with onset between the first years of life and adulthood. Early diagnosis is crucial for effective therapy and long-term survival. The objective of this article is to recognize warning signs among the clinical and laboratory characteristics of LAL-D in pediatric patients through a scope review. SOURCES: Electronic searches in the Embase, PubMed, Livivo, LILACS, Web of Science, Scopus, Google Scholar, Open Gray, and ProQuest Dissertations and Theses databases. The dataset included observational studies with clinical and laboratory characteristics of infants, children and adolescents diagnosed with lysosomal acid lipase deficiency by enzyme activity testing or analysis of mutations in the lysosomal acid lipase gene (LIPA). The reference selection process was performed in two stages. The references were selected by two authors, and the data were extracted in June 2020. SUMMARY OF THE FINDINGS: The initial search returned 1593 studies, and the final selection included 108 studies from 30 countries encompassing 206 patients, including individuals with Wolman disease and cholesteryl ester storage disease (CESD). The most prevalent manifestations in both spectra of the disease were hepatomegaly, splenomegaly, anemia, dyslipidemia, and elevated transaminases. CONCLUSIONS: Vomiting, diarrhea, jaundice, and splenomegaly may be correlated, and may serve as a starting point for investigating LAL-D. Familial lymphohistiocytosis should be part of the differential diagnosis with LAL-D, and all patients undergoing upper gastrointestinal endoscopy should be submitted to intestinal biopsy.

CT features of Wolman disease (lysosomal acid lipase enzyme deficiency) - A case report.

Wolman disease is a lethal rare autosomal recessive disorder defined by the deficiency of acid lipase enzyme. The disease is a lysosomal storage disease. Multiple organs such as adrenal glands, liver, spleen, bone marrow, small bowel loops, and abdominal lymph nodes are infiltrated by the deposition of lipids. Infants generally present with failure to thrive, abdominal distention, vomiting, steatorrhea, and hepatosplenomegaly. Authors' present a 1 month-old male infant with abdominal distention and failure to thrive who was referred for abdomen CT scan. The CT scan revealed stippled calcifications of both enlarged adrenal glands, without the distortion of the adreniform shape, fatty liver, splenomegaly and thickened small bowel loops; characteristic imaging findings of Wolman disease. CT scan is the imaging modality of choice for the recognition of the disease. There is no definite cure explained yet. Further studies are required to find the definite treatment of the disease.

Enzyme replacement therapy and hematopoietic stem cell transplant: a new paradigm of treatment in Wolman disease.

BACKGROUND: Wolman disease is a rare, lysosomal storage disorder in which biallelic variants in the LIPA gene result in reduced or complete lack of lysosomal acid lipase. The accumulation of the substrates; cholesterol esters and triglycerides, significantly impacts cellular function. Untreated patients die within the first 12 months of life. Clinically, patients present severely malnourished, with diarrhoea and hepatosplenomegaly, many have an inflammatory phenotype, including with hemophagocytic lymphohistiocytosis (HLH). Hematopoietic stem cell transplant (HCT) had been historically the only treatment available but has a high procedure-related mortality because of disease progression and disease-associated morbidities. More recently, enzyme replacement therapy (ERT) with dietary substrate reduction (DSR) has significantly improved patient survival. However, ERT is life long, expensive and its utility is limited by anti-drug antibodies (ADA) and the need for central venous access. RESULTS: We describe five Wolman disease patients diagnosed in infancy that were treated at Royal Manchester Children's Hospital receiving ERT with DSR then HCT-multimodal therapy. In 3/5 an initial response to ERT was attenuated by ADA with associated clinical and laboratory features of deterioration. 1/5 developed anaphylaxis to ERT and the other patient died post HCT with ongoing HLH. All patients received allogeneic HCT. 4/5 patients are alive, and both disease phenotype and laboratory parameters are improved compared to when they were on ERT alone. The gastrointestinal symptoms are particularly improved after HCT, with reduced diarrhoea and vomiting. This allows gradual structured normalisation of diet with improved tolerance of dietary fat. Histologically there are reduced cholesterol clefts, fewer foamy macrophages and an improved villous structure. Disease biomarkers also show improvement with ERT, immunotherapy and HCT. Three patients have mixed chimerism after HCT, indicating a likely engraftment-defect in this condition. CONCLUSION: We describe combined ERT, DSR and HCT, multimodal treatment for Wolman disease. ERT and DSR stabilises the sick infant and reduces the formerly described prohibitively high, transplant-associated mortality in this condition. HCT abrogates the problems of ERT, namely attenuating ADA, the need for continuing venous access, and continuing high cost drug treatment. HCT also brings improved efficacy, particularly evident in improved gastrointestinal function and histology. Multimodal therapy should be considered a new paradigm of treatment for Wolman disease patients where there is an attenuated response to ERT, and for all patients where there is a well-matched transplant donor, in order to improve long term gut function, tolerance of a normal diet and quality of life.

Wolman's disease presenting with secondary hemophagocytic lymphohistiocytosis: a case report from Saudi Arabia and literature review.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a rare and potentially fatal syndrome that is characterized by strong activation of the immune system from hyperinflammatory cytokines. Symptoms of HLH patients include fever, hepatosplenomegaly, cytopenia, and hyperferritinemia. Inherited HLH is classified as primary, whereas secondary HLH (sHLH) occurs when acquired from non-inherited reasons that include severe infection, immune deficiency syndrome, autoimmune disorder, neoplasm, and metabolic disorder. Wolman's disease (WD) is a rare and fatal infantile metabolic disorder caused by lysosomal acid lipase deficiency, that exhibits similar clinical signs and symptoms as HLH. This paper reports the case of an infant diagnosed with WD and who presented with sHLH. CASE PRESENTATION: A 4-month-old infant presenting with hepatosplenomegaly, failure to thrive, and other abnormalities. WD diagnosis was confirmed by the presence of the LIPA gene homozygous deletion c.(428 + 1_967-1)_(*1_?)del. The infant also met the HLH-2004 diagnostic criteria. CONCLUSIONS: Metabolic disorder such as WD should be investigated in infants fulfilling the HLH criteria to diagnose the underlying condition. More studies are needed to understand the link between WD and sHLH and to identify appropriate therapies.

Long-term survival with sebelipase alfa enzyme replacement therapy in infants with rapidly progressive lysosomal acid lipase deficiency: final results from 2 open-label studies.

BACKGROUND: If symptomatic in infants, the autosomal recessive disease lysosomal acid lipase deficiency (LAL-D; sometimes called Wolman disease or LAL-D/Wolman phenotype) is characterized by complete loss of LAL enzyme activity. This very rare, rapidly progressive form of LAL-D results in severe manifestations leading to failure to thrive and death, usually by 6 months of age. We report results from 2 open-label studies of enzyme replacement therapy with sebelipase alfa, a recombinant human LAL, in infants with LAL-D: the phase 2/3 Survival of LAL-D Infants Treated With Sebelipase Alfa (VITAL) study (NCT01371825) and a phase 2 dose-escalation study (LAL-CL08 [CL08]; NCT02193867). In both, infants received once-weekly intravenous infusions of sebelipase alfa. RESULTS: The analysis population contained 19 patients (9 in VITAL; 10 in CL08). Kaplan-Meier estimates of survival to 12 months and 5 years of age were 79% and 68%, respectively, in the combined population, and the median age of surviving patients was 5.2 years in VITAL and 3.2 years in CL08. In both studies, median weight-for-age, length-for-age, and mid-upper arm circumference-for-age z scores increased from baseline to end of study. Decreases in median liver and spleen volume over time were noted in both studies. Short-term transfusion-free hemoglobin normalization was achieved by 100% of patients eligible for assessment in VITAL, in an estimated median (95% confidence interval [CI]) time of 4.6 (0.3-16.6) months. In CL08, short-term transfusion-free hemoglobin normalization was achieved by 70% of patients eligible for assessment, in an estimated median (95% CI) time of 5.5 (3.7-19.6) months. No patient discontinued treatment because of treatment-emergent adverse events. Most infusion-associated reactions (94% in VITAL and 88% in CL08) were mild or moderate in severity. CONCLUSIONS: The findings of these 2 studies of infants with rapidly progressive LAL-D demonstrated that enzyme replacement therapy with sebelipase alfa prolonged survival with normal psychomotor development, improved growth, hematologic parameters, and liver parameters, and was generally well tolerated, with an acceptable safety profile.

• Lysosomal acid lipase deficiency (LAL-D) is a rare, inherited disease in which fatty material (cholesterol and triglycerides) becomes trapped in cells throughout the body, causing organ damage.• Infants can experience a particularly aggressive form of this disease where the functioning of the liver and intestine is impaired, thus leading to an enlarged abdomen and failure to grow and thrive.• If left untreated, LAL-D in infants leads to death, usually by 6 months of age.• This publication reports the results from 2 studies involving 19 infants with rapidly progressive LAL-D; infants received once-weekly intravenous infusions of sebelipase alfa for up to 3 or 5 years, depending on the study.• Results show that with sebelipase alfa treatment, the likelihood of an infant with LAL-D surviving to 12 months of age is 79% and the likelihood of surviving to 5 years of age is 68%.• Throughout both studies, treatment with sebelipase alfa was associated with (1) improvements in growth (weight, length/height, and arm circumference), (2) improvements in liver function, and (3) a decrease in liver and spleen size.• All patients experienced 1 or more adverse events (unwanted side effects), most of which were mild or moderate in severity; no patient stopped receiving treatment because of these events.