Inhibition of UDP-glucosylceramide synthase in mice prevents Gaucher disease-associated B-cell malignancy

Profile of eliglustat tartrate in the management of Gaucher disease

Gaucher disease (GD) is a lysosomal storage disorder caused by the deficient activity of acid beta glucosidase, with consequent accumulation of glucosylceramide in the spleen, liver, bone marrow, and various organs and tissues. Currently, the gold standard for GD treatment is enzyme replacement therapy (ERT). The efficacy of ERT in improving or stabilizing the visceral and hematological symptoms of GD is well-proven. However, since ERT has to be administered by frequent intravenous infusions, this therapeutic approach has an important impact on the patient’s quality of life. Eliglustat tartrate is a new substrate reduction therapy for GD, which acts as a specific and potent inhibitor of glucosylceramide synthase and can be administered orally. This review summarizes the results of the preclinical and clinical trials, which experimented with eliglustat, and discusses its possible role in the management of GD, when compared to the currently available treatments and the new experimental approaches.

Eliglustat tartrate for the treatment of adults with type 1 Gaucher disease

The purpose of this article is to review eliglustat tartrate, a substrate reduction therapy, for the treatment of Gaucher disease type 1 (GD1). GD is an rare inborn error of metabolism caused by accumulation of lipid substrates such as glucosylceramide within the monocyte-macrophage system that affects the body by causing enlargement of the spleen and liver, destruction of bone, and abnormalities of the lungs and blood, such as anemia, thrombocytopenia, and leukopenia. GD is classified into three types: GD1, a chronic and non-neuronopathic disease accounting for 95% of GD cases; and types 2 and 3 (GD2 GD3) which are more progressive diseases with no approved drugs available at this time. Treatment options for GD1 include enzyme replacement therapy and substrate reduction therapy. Eliglustat works by inhibiting UDP-glucosylceramide synthase, the first enzyme that catalyzes the biosynthesis of glycosphingolipids, thus reducing the load of glucosylceramide influx into the lysosome. Eliglustat was approved by the US Food and Drug Administration after three Phase I, two Phase II, and two Phase III clinical trials. The dose of eliglustat is 84 mg twice a day or once daily depending on the cytochrome P450 2D6 genotype of the patient.

Gaucher disease and comorbidities: B-cell malignancy and parkinsonism

Data emerging from the International Collaborative Gaucher Group (ICGG) Gaucher Registry together with other contemporary clinical surveys have revealed a close association between Gaucher disease and non-Hodgkin's B-cell lymphoma and myeloma and Gaucher disease and Parkinson's disease. Several possible explanations for increased B-cell proliferation and neoplasia in Gaucher disease have been proposed, including the possible influence of sphingosine (derived from the extra lysosomal metabolism of glucosylceramide), gene modifiers, splenectomy and immune system deregulation induced by cytokines, chemokines, and hydrolases released from Gaucher cells. Parkinson's disease is frequently seen in the otherwise-healthy relatives of Gaucher disease patients leading to the finding that GBA mutations represent a genetic risk factor for Parkinson's disease. The mechanism of the association between GBA mutations and Parkinson's disease has yet to be elucidated but the pathogenesis appears distinct from that of Gaucher disease. Several pathogenic pathways have been proposed including lysosomal and/or mitochondrial dysfunction. The effect of Gaucher disease specific therapies on the incidence of cancer or Parkinson's disease are not clear and will likely be evaluated in future ICGG Gaucher Registry studies.