What is required for achieving hepatitis C virus elimination in Singapore? A modeling study
JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY
Authors: Chaillon, Antoine; Thurairajah, Prem Harichander; Hsiang, John Chen; Martin, Natasha K.
Abstract
Background and Aim The vast majority of hepatitis C virus (HCV) infection in Singapore is among those with a history of injecting drug use (IDU), yet harm reduction is not available and what is required to achieve the World Health Organization (WHO) HCV elimination targets (80% incidence reduction and 65% mortality reduction by 2030) is unknown. We model the intervention scale-up required to achieve WHO targets in Singapore. Methods A dynamic model of HCV transmission and progression among those with a history of IDU was calibrated to Singapore, a setting with declining IDU and no harm reduction (similar to 11 000 people with IDU history in 2017 and 45% HCV seropositive). We projected HCV treatment scale-up from 2019 required to achieve WHO targets with varying prioritization scenarios, with/without opiate substitution therapy scale-up (to 40% among people who inject drugs [PWID]). Results We estimated 3855 (95% confidence interval: 2635-5446) chronically HCV-infected individuals with a history of IDU and 148 (87-284) incident HCV cases in Singapore in 2019. Reaching the HCV incidence target requires 272 (187-384) treatments in 2019, totaling 2444 (1683-3452) across 2019-2030. By prioritizing PWID or PWID and cirrhotics, 60% or 30% fewer treatments are required, respectively, whereas the target cannot be achieved with cirrhosis prioritization. Opiate substitution therapy scale-up reduces treatments required by 21-24%. Achieving both WHO targets requires treating 631 (359-1047) in 2019, totaling 3816 (2664-5423) across 2019-2030. Conclusions Hepatitis C virus elimination is achievable in Singapore but even with declining IDU requires immediate treatment scale-up among PWID. Harm reduction provision reduces treatments required and provides additional benefits.
Discovery of novel Hepatitis C virus inhibitor targeting multiple allosteric sites of NS5B polymerase
INFECTION GENETICS AND EVOLUTION
Authors: Khalid, Hina; Landry, Koloko Brice; Ijaz, Bushra; Ashfaq, Usman Ali; Ahmed, Matloob; Kanwal, Afshan; Froeyen, Matheus; Mirza, Muhammad Usman
Abstract
HCV is a viral infection posing a severe global threat when left untreated progress to end-stage liver disease, including cirrhosis and HCC. The NS5B polymerase of HCV is the most potent target that harbors four allosteric binding sites that could interfere with the HCV infection. We present the discovery of a novel synthetic compound that harbors the potential of NS5B polymerase inhibition. All eight compounds belonging to the benzothiazine family of heterocycles displayed no cellular cytotoxicity in HepG2 cells at nontoxic dose concentration (200 mu M). Subsequently, among eight compounds of the series, merely compound 5b exhibited significant inhibition of the expression of the HCV NS5B gene as compared to DMSO control in semi-quantitative PCR. Based on our western blot result, 5b at the range of 50, 100 and 200 mu M induced 20, 40, and 70% inhibition of NS5B protein respectively. To estimate the binding potential, 5b was docked at respective allosteric sites followed by molecular dynamics (MD) simulations for a period of 20 ns. In addition, binding free energy calculation by MM-GB/PBSA method revealed a conserved interaction profile of residues lining the allosteric sites in agreement with the reported NS5B co-crystallized inhibitors. The presented results provide important information about a novel compound 5b which may facilitate the the discovery of novel inhibitors that tends to target multiple sites on NS5B polymerase.