Search

Abstract Introduction Exploration of sexual and drug use behaviours following treatment for recent hepatitis C virus (HCV) is limited. This analysis modelled behavioural trajectories following treatment for recent HCV and assessed reinfection. Methods Participants treated for recent HCV in an international trial (enrolled 2017–2019) were followed at 3‐monthly intervals for up to 2 years to assess longitudinal behaviours. Population‐averaged changes were assessed using generalized estimating equations. Distinct behavioural trajectories were identified using group‐based trajectory modelling. HCV reinfection incidence was calculated using person‐years (PY) of observation. Results During the follow‐up of 212 participants (84% gay and bisexual men [GBM]; 69% HIV; 26% current injecting drug use [IDU]), behavioural trajectories for IDU and stimulant use (past month) did not change. However, population‐averaged decreases in the likelihood of daily IDU (adjusted odds ratio [AOR] 0.83; 95% CI 0.72, 0.95) and opioid use (AOR 0.84; 95% CI 0.75, 0.93) were observed. Among GBM, behavioural trajectories for chemsex did not change. Population‐averaged decreases in condomless anal intercourse with casual male partners (CAI‐CMP) (AOR 0.95; 95% CI 0.90, 0.99) and group‐sex (AOR 0.86; 95% CI 0.80, 0.93) were observed, but masked distinct trajectories. While a proportion had a decreased probability of CAI‐CMP (23%) and group‐sex (59%) post‐treatment, a substantial proportion retained a high probability of these behaviours. High HCV reinfection incidence was observed for the sustained high probability IDU (33.0/100 PY; 95% CI 17.7, 61.3) and chemsex (23.3/100 PY; 95% CI 14.5, 37.5) trajectories. Conclusions Limited sexual and drug use behavioural change was observed following treatment for recent HCV, supporting access to surveillance and (re)treatment.

Australia was one of the first countries with unrestricted access to government subsidized direct‐acting antiviral (DAA) therapy for adults with chronic hepatitis C virus. This study assessed real‐world DAA treatment outcomes across a diverse range of Australian clinical services and evaluated factors associated with successful treatment and loss to follow‐up. Real‐world Effectiveness of Antiviral therapy in Chronic Hepatitis C (REACH‐C) consisted a national observational cohort of 96 clinical services including specialist clinics and less traditional settings such as general practice. Data were obtained on consecutive individuals who commenced DAAs from March 2016 to June 2019. Effectiveness was assessed by sustained virological response ≥12 weeks following treatment (SVR) using intention‐to‐treat (ITT) and per‐protocol (PP) analyses. Within REACH‐C, 10,843 individuals initiated DAAs (male 69%; ≥50 years 52%; cirrhosis 22%). SVR data were available in 85% (9,174 of 10,843). SVR was 81% (8,750 of 10,843) by ITT and 95% (8,750 of 9,174) by PP. High SVR (≥92%) was observed across all service types and participant characteristics. Male gender (adjusted odds ratio [aOR] 0.56, 95% confidence interval [CI] 0.43‐0.72), cirrhosis (aOR 0.52, 95% CI 0.41‐0.64), recent injecting drug use (IDU; aOR 0.64, 95% CI 0.46‐0.91) and previous DAA treatment (aOR 0.50, 95% CI 0.28‐0.90) decreased the likelihood of achieving SVR. Multiple factors modified the likelihood of loss to follow‐up including IDU ± opioid agonist therapy (OAT; IDU only: aOR 1.75, 95% CI 1.44‐2.11; IDU + OAT: aOR 1.39, 95% CI 1.11‐1.74; OAT only, aOR 1.36; 95% CI 1.13‐1.68) and age (aOR 0.97, 95% CI 0.97‐0.98). Conclusion: Treatment response was high in a diverse population and through a broad range of services following universal access to DAA therapy. Loss to follow‐up presents a real‐world challenge. Younger people who inject drugs were more likely to disengage from care, requiring innovative strategies to retain them in follow‐up.

We assessed the predictive capacity of the HCV-MOSAIC risk score, originally developed for primary early HCV infection, as a screening tool for HCV reinfection in 103 men who have sex with men (MSM) with HIV using data from the MOSAIC cohort, including MSM with HIV/HCV-coinfection who became reinfected (cases, n = 27) or not (controls, n = 76) during follow-up. The overall predictive capacity of the score was assessed using the area under the receiver operating characteristic (AUROC) curve. The effects of covariates on the receiver operating characteristic (ROC) curve were assessed using parametric ROC regression. The score cut-off validated for primary early infection (≥2.0) was used, from which the sensitivity and specificity were calculated. The AUROC was 0.74 (95% confidence interval (CI) = 0.63–0.84). Group sex significantly increased the predictive capacity. Using the validated cut-off, sensitivity was 70.4% (95%CI = 49.8–86.2%) and specificity was 59.2% (95%CI: 47.3–70.4%). External validation from a cohort of 25 cases and 111 controls, all MSM with HIV, resulted in a sensitivity of 44.0% (95%CI = 24.4–65.1) and specificity of 71.2% (95%CI = 61.8–79.4). The HCV-MOSAIC risk score may be useful for identifying individuals at risk of HCV reinfection. In sexual health or HIV-care settings, this score could help guide HCV-RNA testing in MSM with a prior HCV infection.