The HDL mimetic CER-001 remodels plasma lipoproteins and reduces kidney lipid deposits in inherited lecithin:cholesterol acyltransferase deficiency

BACKGROUND

Kidney failure is the major cause of morbidity and mortality in familial lecithin:cholesterol acyltransferase deficiency (FLD), a rare inherited lipid disorder with no cure. Lipoprotein X (LpX), an abnormal lipoprotein, is primarily accountable for nephrotoxicity.

METHODS

CER-001 was tested in an FLD patient with dramatic kidney disease for 12 weeks.

RESULTS

Infusions of CER-001 normalized the lipoprotein profile, with a disappearance of the abnormal LpX in favour of normal-sized LDL. The worsening of kidney function was slowed by the treatment, and kidney biopsy showed a slight reduction of lipid deposits and a stabilization of the disease. In vitro experiments demonstrate that CER-001 progressively reverts lipid accumulation in podocytes by a dual effect: remodelling plasma lipoproteins and removing LpX-induced lipid deposit.

CONCLUSION

This study demonstrates that CER-001 may represent a therapeutic option in FLD patients. It also has the potential to be beneficial in other renal diseases characterized by kidney lipid deposits.

High Density Lipoproteins: Is There a Comeback as a Therapeutic Target?

Low plasma levels of High Density Lipoprotein (HDL) cholesterol (HDL-C) are associated with increased risks of atherosclerotic cardiovascular disease (ASCVD). In cell culture and animal models, HDL particles exert multiple potentially anti-atherogenic effects. However, drugs increasing HDL-C have failed to prevent cardiovascular endpoints. Mendelian Randomization studies neither found any genetic causality for the associations of HDL-C levels with differences in cardiovascular risk. Therefore, the causal role and, hence, utility as a therapeutic target of HDL has been questioned. However, the biomarker "HDL-C" as well as the interpretation of previous data has several important limitations: First, the inverse relationship of HDL-C with risk of ASCVD is neither linear nor continuous. Hence, neither the-higher-the-better strategies of previous drug developments nor previous linear cause-effect relationships assuming Mendelian randomization approaches appear appropriate. Second, most of the drugs previously tested do not target HDL metabolism specifically so that the futile trials question the clinical utility of the investigated drugs rather than the causal role of HDL in ASCVD. Third, the cholesterol of HDL measured as HDL-C neither exerts nor reports any HDL function. Comprehensive knowledge of structure-function-disease relationships of HDL particles and associated molecules will be a pre-requisite, to test them for their physiological and pathogenic relevance and exploit them for the diagnostic and therapeutic management of individuals at HDL-associated risk of ASCVD but also other diseases, for example diabetes, chronic kidney disease, infections, autoimmune and neurodegenerative diseases.

Novel ABCA1 peptide agonists with antidiabetic action

Previously, apoE-derived ABCA1 agonist peptides have been shown to possess anti-atherosclerotic and possibly antidiabetic properties. Here we assessed the in vitro and in vivo actions of a second generation of ABCA1 peptide agonists, CS6253 and T6991-2, on glucose homeostasis. The results show that these two peptides improve glucose tolerance in a prediabetic diet-induced obesity mouse model by enhancing insulin secretion. It was further demonstrated that T6991-2 also improved glucose tolerance in leptin-deficient (ob/ob) mice. CS6253 increased insulin secretion both under basal conditions and in response to high glucose stimulation in pancreatic INS-1 β-cells rendered leptin receptor deficient with specific siRNA. Additional in vitro cell studies suggest that the CS6253 agonist attenuates hepatic gluconeogenesis and glucose transport. It also potentiates insulin-stimulated glucose uptake and utilization. These observed anti-diabetic actions suggest additional benefits of the CS6253 and T6991-2 ABCA1 peptide agonists for cardiovascular disease beyond their direct anti-atherosclerosis properties previously described.

Intravenous toxicity and toxicokinetics of an HDL mimetic, Fx-5A peptide complex, in cynomolgus monkeys

Fx-5A peptide complex (Fx-5A), a High Density Lipoproteins (HDL) mimetic, has been shown to reduce atherosclerosis. The safety and toxicokinetics of Fx-5A administered IV by 30 min infusion at 8, 25 or 75 mg/kg body weight or vehicle, once every other day for 27 days, were assessed in cynomolgus monkeys. The Fx-5A was well tolerated at all doses. At the highest dose, there were statistically significant effects on hematology and clinical chemistry parameters that were considered non-adverse. Dose-dependent recoverable non-adverse erythrocytes morphological changes (acanthocytes, echinocytes, spherocytes, microcytes, and/or schistocytes) were observed. Fx-5A was not hemolytic in in-vitro fresh NHP or human blood assay. There were no Fx-5A-related statistically significant changes for any cardiovascular function, ECG or respiratory parameters, when compared to control. In addition, there were no Fx-5A-related effects on organ weights, macroscopic or microscopic endpoints. Finally, Fx-5A exhibited sporadic non-appreciable detection of anti-Fx-5A antibodies and a dose-dependent linear toxicokinetics with T_1/2 value ranges from 2.7 to 6.2 h. In conclusion, the No Observed Adverse Effect Level was considered to be 75 mg/kg/day with associated exposures average C_max and AUC_0-last of 453 μg/mL and 2232 h μg/mL, respectively, on Day 27.