Eliglustat, marketed by Genzyme as CERDELGA, is a glucosylceramide synthase inhibitor indicated for the long-term treatment of type 1 Gaucher disease who are CYP2D6 extensive metabolizers, intermediate metabolizers, or poor metabolizers (PMs) as detected by an FDA-cleared test.

Miglustat, an N-alkylated imino sugar, is a synthetic analogue of D-glucose. Miglustat is an inhibitor of the enzyme glucosylceramide synthase, which is a glucosyl transferase enzyme responsible for catalyzing the formation of glucosylceramide (glucocerebroside). Glucosylceramide is a substrate for the endogenous glucocerebrosidase, an enzyme that is deficient in Gaucher's disease. The accumulation of glucosylceramide due to the absence of glucocerebrosidase results in the storage of this material in the lysosomes of tissue macrophages, leading to widespread pathology due to infiltration of lipid-engorged macrophages in the viscera, lymph nodes, and bone marrow. This results in secondary hematologic consequences including sever anemia and thrombocytopenia, in addition to the characteristic progressive hepatosplenomegaly, as well as skeletal complications including osteonecrosis and osteopenia with secondary pathological fractures. Miglustat functions as a competitive and reversible inhibitor of the enzyme glucosylceramide synthase, the initial enzyme in a series of reactions which results in the synthesis of most glycosphingolipids. The goal of treatment with miglustat is to reduce the rate of glycosphingolipid biosynthesis so that the amount of glycosphingolipid substrate is reduced to a level which allows the residual activity of the deficient glucocerebrosidase enzyme to be more effective (substrate reduction therapy), reducing the accumulation of glucocerebroside in macrophages. In vitro and in vivo studies have shown that miglustat can reduce the synthesis of glucosylceramide-based glycosphingolipids. In clinical trials, miglustat improved liver and spleen volume, as well as hemoglobin concentration and platelet count. Inhibition of glycosphingolipid synthesis has also shown to reduce intracellular lipid storage, improve fluid-phase endosomal uptake and normalize lipid transport in peripheral blood B lymphocytes of NP-C patients, which results in a decrease in the potentially neurotoxic accumulation of gnagliosides GM2 and GM3, lactosylceramide and glucosylceramide, possibly preventing further neuronal damage. Other studies have also suggested that miglustat may indirectly modulate intracellular calcium homeostasis through its effects on glucosylceramide levels, and evidence has shown that an initiating factor in the pathogenesis of NP-C may be impaired calcium homeostasis related to sphingosine storage. Therefore, the effect that miglustat exerts on intracellular calcium levels may influence an important underlying pathogenic mechanism of NP-C. Miglustat is used for the treatment of adult patients with mild to moderate type 1 (nonneuropathic) Gaucher's disease for whom enzyme replacement therapy is not a therapeutic option (e.g. due to constraints such as allergy, hypersensitivity, or poor venous access). Now approved in some countries for the treatment of progressive neurological symptoms in adult and pediatric patients with Niemann-Pick disease type C (NP-C). Miglustat is marketed under the trade name Zavesca.

Ibiglustat (GZ/SAR402671 or Genz-682452) is a small molecule inhibitor of glucosylceramide synthase. Ibiglustat has been demonstrated to effectively lower glycosphingolipid synthesis. Genzyme, a Sanofi Company is developing Ibiglustat for the treatment of Parkinson's Disease, Gaucher Disease, and Fabry Disease.

Genz-123346 is a potent and selective glucosylceramide synthase (GCS) inhibitor that blocks the conversion of ceramide to GL1. It has been studied as a potential treatment of diabetes mellitus, polycystic kidney disease and fatty liver disease. Genz-123346 improved glucose tolerance and increased insulin sensitivity in two animal models of type 2 diabetes. In Zucker diabetic fatty rats, treatment with Genz-123346 significantly lowered blood glucose levels and partially prevented the normal deterioration of pancreatic β-cell function over time and preserved the ability of the islets to secrete insulin. In the high-fat–fed diet-induced obese mice, Genz-123346 essentially normalized A1C levels to that of the lean animals. Inhibiting GSL synthesis ameliorates the liver pathology associated with obesity and diabetes in mice model. Blockade of kidney glucosylceramide GlcCer accumulation with the GCS inhibitor Genz-123346 effectively inhibits cystogenesis in mouse models orthologous to human autosomal dominant polycystic kidney disease (PKD) (Pkd1 conditional knockout mice) and nephronophthisis (jck and pcy mice). Molecular analysis in vitro and in vivo indicated that inhibition of GCS by Genz-123346 inhibited the AKT-mTOR signaling pathway. It induced autophagy via the AKT-mTOR signaling pathway in HEK293T cells, increased autophagy flux and reduced mutant α-syn levels in mouse primary neurons potentially via indendent mechanisms. Exposure of cells to Genz-123346 and to other GCS inhibitors at non-toxic concentrations can enhance the killing of tumor cells by cytotoxic anti-cancer agents. This chemosensitizing activity was unrelated to lowering intracellular glycosphingolipid levels. Genz-123346 is a substrate for multi-drug resistance efflux pumps such as P-gp (ABCB1, gP-170). In cell lines selected to over-express P-gp or which endogenously express P-gp, chemosensitization by Genz-123346 was primarily due to the effects on P-gp function. Genz-123346 has little effect on 1-O-acylceramide synthase activity at concentrations that effectively inhibit GL1 synthase activity and therefore do not significantly elevate cell ceramide levels in vitro. Unlike N-butyldeoxynojirimycin (NB-DNJ), another inhibitor of GCS Genz-123346 does not inhibit α-glucosidase or glucocerebrosidase.

Eliglustat, marketed by Genzyme as CERDELGA, is a glucosylceramide synthase inhibitor indicated for the long-term treatment of type 1 Gaucher disease who are CYP2D6 extensive metabolizers, intermediate metabolizers, or poor metabolizers (PMs) as detected by an FDA-cleared test.

Ibiglustat (GZ/SAR402671 or Genz-682452) is a small molecule inhibitor of glucosylceramide synthase. Ibiglustat has been demonstrated to effectively lower glycosphingolipid synthesis. Genzyme, a Sanofi Company is developing Ibiglustat for the treatment of Parkinson's Disease, Gaucher Disease, and Fabry Disease.

Ibiglustat (GZ/SAR402671 or Genz-682452) is a small molecule inhibitor of glucosylceramide synthase. Ibiglustat has been demonstrated to effectively lower glycosphingolipid synthesis. Genzyme, a Sanofi Company is developing Ibiglustat for the treatment of Parkinson's Disease, Gaucher Disease, and Fabry Disease.

Ibiglustat (GZ/SAR402671 or Genz-682452) is a small molecule inhibitor of glucosylceramide synthase. Ibiglustat has been demonstrated to effectively lower glycosphingolipid synthesis. Genzyme, a Sanofi Company is developing Ibiglustat for the treatment of Parkinson's Disease, Gaucher Disease, and Fabry Disease.

Genz-123346 is a potent and selective glucosylceramide synthase (GCS) inhibitor that blocks the conversion of ceramide to GL1. It has been studied as a potential treatment of diabetes mellitus, polycystic kidney disease and fatty liver disease. Genz-123346 improved glucose tolerance and increased insulin sensitivity in two animal models of type 2 diabetes. In Zucker diabetic fatty rats, treatment with Genz-123346 significantly lowered blood glucose levels and partially prevented the normal deterioration of pancreatic β-cell function over time and preserved the ability of the islets to secrete insulin. In the high-fat–fed diet-induced obese mice, Genz-123346 essentially normalized A1C levels to that of the lean animals. Inhibiting GSL synthesis ameliorates the liver pathology associated with obesity and diabetes in mice model. Blockade of kidney glucosylceramide GlcCer accumulation with the GCS inhibitor Genz-123346 effectively inhibits cystogenesis in mouse models orthologous to human autosomal dominant polycystic kidney disease (PKD) (Pkd1 conditional knockout mice) and nephronophthisis (jck and pcy mice). Molecular analysis in vitro and in vivo indicated that inhibition of GCS by Genz-123346 inhibited the AKT-mTOR signaling pathway. It induced autophagy via the AKT-mTOR signaling pathway in HEK293T cells, increased autophagy flux and reduced mutant α-syn levels in mouse primary neurons potentially via indendent mechanisms. Exposure of cells to Genz-123346 and to other GCS inhibitors at non-toxic concentrations can enhance the killing of tumor cells by cytotoxic anti-cancer agents. This chemosensitizing activity was unrelated to lowering intracellular glycosphingolipid levels. Genz-123346 is a substrate for multi-drug resistance efflux pumps such as P-gp (ABCB1, gP-170). In cell lines selected to over-express P-gp or which endogenously express P-gp, chemosensitization by Genz-123346 was primarily due to the effects on P-gp function. Genz-123346 has little effect on 1-O-acylceramide synthase activity at concentrations that effectively inhibit GL1 synthase activity and therefore do not significantly elevate cell ceramide levels in vitro. Unlike N-butyldeoxynojirimycin (NB-DNJ), another inhibitor of GCS Genz-123346 does not inhibit α-glucosidase or glucocerebrosidase.