Discovery of a tricyclic farnesoid X receptor agonist HEC96719, a clinical candidate for treatment of non-alcoholic steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) is becoming the most predominant burden of chronic liver disease worldwide. Non-alcoholic steatohepatitis (NASH), the progressive form of NAFLD, can develop into cirrhosis and hepatocellular cancer. Unfortunately, current options for therapeutic treatment of NASH are very limited. Among multiple pathways in NASH, farnesoid X receptor (FXR), a nuclear bile acid receptor, is well-recognized as an important effective target. Here we report the synthesis and characterization of compound HEC96719 a novel tricyclic FXR agonist based on a prior high-affinity nonsteroidal molecule GW4064. HEC96719 exhibits excellent potency superior to GW4064 and obeticholic acid in in vitro and in vivo assays of FXR activation. It also shows higher FXR selectivity and more favorable tissue distribution dominantly in liver and intestine. Preclinical data on pharmacokinetic properties, efficacy, and safety profiles overall indicate that HEC96719 is a promising drug candidate for NASH treatment.

Current and emerging pharmacological options for the treatment of nonalcoholic steatohepatitis

Nonalcoholic fatty liver disease (NAFLD) is a highly prevalent disease and important unmet medical need. Current guidelines recommend, under specific restrictions, pioglitazone or vitamin E in patients with NASH and significant fibrosis, but the use of both remains off-label. We summarize evidence on medications for the treatment of nonalcoholic steatohepatitis (NASH), since NASH has been mainly associated with higher morbidity and mortality. Some of these medications are currently in phase 3 clinical trials, including obeticholic acid (a farnesoid X receptor agonist), elafibranor (a peroxisome proliferator activated receptor [PPAR]-α/δ dual agonist), cenicriviroc (a CC chemokine receptor antagonist), MSDC-0602 K (a PPAR sparing modulator), selonsertib (an apoptosis signal-regulating kinase-1 inhibitor) and resmetirom (a thyroid hormone receptor agonist). A significant research effort is also targeting PPARs and selective PPAR modulators, including INT131 and pemafibrate, with the expectation that novel drugs may have beneficial effects similar to those of pioglitazone, but without the associated adverse effects. Whether these and other medications could offer tangible therapeutic benefits, alone or in combination, apparently on a background of lifestyle modification, i.e. exercise and a healthy dietary pattern (e.g. Mediterranean diet) remain to be proven. In conclusion, major advances are expected for the treatment of NASH.

Farnesoid X receptor agonist GW4064 indirectly inhibits HCV entry into cells via down-regulating scavenger receptor class B type I

Farnesoid X receptor (FXR) agonists play important regulatory roles in bile acid, lipid and glucose metabolism in vitro and in vivo. Thus, FXR agonists exhibit potential therapeutic effects on metabolism-related diseases that are associated with extrahepatic manifestations induced by hepatitis C virus (HCV) infection. This study investigated the effect and mechanism of FXR agonist GW4064 against HCV in vitro to explore the potential application of FXR agonists. Results showed that GW4064 and other FXR agonists have potent antiviral activity against HCV in Huh7.5 cells. GW4064 down-regulated the expression of scavenger receptor class B type I protein via FXR and thereby indirectly inhibited HCV entry into cells, leading to interruption of HCV life cycle. GW4064 also exhibited synergistic anti-HCV effect with known direct-acting antiviral agents (DAAs) used in the clinic and remained sensitive to DAA-resistant HCV mutations. Therefore, FXR agonists are also a kind of antiviral agent, and might be helpful in treatment of HCV-induced hepatic and extrahepatic manifestations.

Agonist of farnesoid X receptor protects against bile acid induced damage and oxidative stress in mouse placenta--a study on maternal cholestasis model

INTRODUCTION

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific disorder, which is characterized by raised serum bile acid level and potential adverse fetal outcome. Farnesoid X receptor (FXR), also known as a bile acid receptor, was found to be expressed in placenta with low level. Whether activation of FXR by specific agonists could regulate the pathogenesis of ICP is still unclear.

METHODS

A model of maternal cholestasis was induced by administration of 17α-ethynylestradiol (E2) in pregnant mice for 6 days. We explored the regulatory effect of WAY-362450 (W450), a highly selective and potent FXR agonist on placenta.

RESULTS

In this study, we demonstrated that administration of E2 increased bile acid levels in mouse serum, liver and amniotic fluid. Bile acid levels were significantly decreased after W450 treatment. W450 protected against the impairment of placentas induced by E2, including severe intracellular edema and apoptosis of trophoblasts. Moreover, W450 significantly induced the expressions of FXR target bile acid transport gene ATP-binding cassette, sub-family B (MDR/TAP), member 11 (Abcb11;Bsep) in placenta. W450 could also attenuate placental oxidative stress and increase the expressions of antioxidant enzymes Prdx1 and Prdx3.

DISCUSSION AND CONCLUSION

In conclusion, our data demonstrated that FXR agonist W450 modulated bile acid balance and protected against placental oxidative stress. Thus, our results support that potent FXR agonists might represent promising drugs for the treatment of ICP.

Activation of farnesoid X receptor attenuates hepatic injury in a murine model of alcoholic liver disease

Alcoholic liver disease (ALD) is a common cause of advanced liver disease, and considered as a major risk factor of morbidity and mortality worldwide. Hepatic cholestasis is a pathophysiological feature observed in all stages of ALD. The farnesoid X receptor (FXR) is a member of the nuclear hormone receptor superfamily, and plays an essential role in the regulation of bile acid, lipid and glucose homeostasis. However, the role of FXR in the pathogenesis and progression of ALD remains largely unknown. Mice were fed Lieber-DeCarli ethanol diet or an isocaloric control diet. We used a specific agonist of FXR WAY-362450 to study the effect of pharmacological activation of FXR in alcoholic liver disease. In this study, we demonstrated that FXR activity was impaired by chronic ethanol ingestion in a murine model of ALD. Activation of FXR by specific agonist WAY-362450 protected mice from the development of ALD. We also found that WAY-362450 treatment rescued FXR activity, suppressed ethanol-induced Cyp2e1 up-regulation and attenuated oxidative stress in liver. Our results highlight a key role of FXR in the modulation of ALD development, and propose specific FXR agonists for the treatment of ALD patients.