FXR inhibition reduces ACE2 expression, SARS-CoV-2 infection and may improve COVID-19 outcome (preprint)

Prevention of SARS-CoV-2 entry in cells through the modulation of viral host receptors, such as ACE2, could represent a new therapeutic approach complementing vaccination. However, the mechanisms controlling ACE2 expression remain elusive. Here, we identify the farnesoid X receptor (FXR) as a direct regulator of ACE2 transcription in multiple COVID19-affected tissues, including the gastrointestinal and respiratory systems. We demonstrate that FXR antagonists, including the over-the-counter compound z-guggulsterone (ZGG) and the off-patent drug ursodeoxycholic acid (UDCA), downregulate ACE2 levels, and reduce susceptibility to SARS-CoV-2 infection in lung, cholangiocyte and gut organoids. We then show that therapeutic levels of UDCA downregulate ACE2 in human organs perfused ex situ and reduce SARS-CoV-2 infection ex vivo. Finally, we perform a retrospective study using registry data and identify a correlation between UDCA treatment and positive clinical outcomes following SARS-CoV-2 infection, including hospitalisation, ICU admission and death. In conclusion, we identify a novel function of FXR in controlling ACE2 expression and provide evidence that this approach could be beneficial for reducing SARS-CoV-2 infection, thereby paving the road for future clinical trials.

Drug-Induced Liver Injury Associated with Lopinavir- Ritonavir in Patients with COVID-19: A Disproportionality Analysis of U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) Data (preprint)

Background Liver injury has been documented independently in novel coronavirus disease 2019 (COVID-19) patients and patients treated with lopinavir-ritonavir.Objective to investigate the drug-induced liver injury associated with lopinavir-ritonavir among the patients with COVID-19.Methods We conducted a disproportionality analysis of US Food and Drug Administration Adverse Event Reporting System (FAERS) between 2020Q1 and 2020Q3 to evaluate the association between lopinavir-ritonavir and risk of drug-induced liver injury (or severe drug-induced liver injury) and calculated their reporting odds ratios (RORs) with 95% confidence intervals (CIs).Results A total of 1,754 reports of drug-induced liver injury in patients with COVID-19. The ROR for drug-induced liver injury was 1.4 (95% CI, 1.1–1.7), 3.6 (95% CI, 2.7–4.7), and 0.8 (95% CI, 0.7-1.0) when comparing lopinavir-ritonavir with all other drugs, hydroxychloroquine/chloroquine only, and remdesivir, respectively. For severe drug-induced liver injury, RORs for lopinavir-ritonavir provided evidence of an association compared with all other drugs (ROR, 4.9; 95% CI, 3.7–6.5), compared with hydroxychloroquine/chloroquine only (ROR, 4.3; 95% CI, 3.0-6.2), and compared with remdesivir (ROR, 10.4; 95% CI, 7.2–15.0).Conclusions In the FAERS, we observed a disproportional signal for severe drug-induced liver injury associated with lopinavir-ritonavir in patients with COVID-19.