1. Hepatitis C treatment and reinfection surveillance among people who inject drugs in a low-threshold program. And new models to reach those hard to reach; results from Point of Care testing and treatment in a nurse led and a peer led mobile clinic
Abstract
Aim 1: to evaluate HCV-treatment effectiveness, estimate reinfection rates, and demonstrate the feasibility of reinfection surveillance and retreatment among people who inject drugs (PWID). This abstract presents a recently published study (Midgard et al. IJDP 2021).
Design: Prospective observational study including consecutive HCV-RNA positive individuals attending a low-threshold clinic in Oslo, 2013-2020. Participants were offered individually tailored HCV-treatment and post-treatment HCV-RNA surveillance at three months intervals.
363 of 488 HCV-RNA positive individuals-initiated treatment. All participants had a history of injecting drug use, 70.1% reported recent injecting, and 71.1% received opioid agonist treatment. Excluding those with HCV-RNA results pending, virologic response was achieved in 306/340 participants. Also excluding those with loss to follow-up, virologic response was achieved in 306/323. Reinfection surveillance was accomplished in 297 individuals (308.2 PY of follow-up; median 0.50 years). Eight cases of reinfection were detected for an incidence of 2.60/100 PY (95% CI 1.12–5.11) overall, and 3.74/100 PY (95% CI 1.62–7.37) among those with injecting drug use during follow-up (n=205). Reinfection was associated with younger age (IRR 0.37; 95% CI 0.18– 0.74); all cases occurred in participants aged below 49 years with ongoing injecting drug use and a mix of heroin/amphetamine use. Successful retreatment was provided in all cases and no second reinfections were observed.
The findings consolidate previous evidence supporting the effectiveness of HCV-treatment among PWID, provide novel data on reinfection rates and associated factors, and demonstrate the feasibility of reinfection surveillance and retreatment in a real-world setting.
Aim 2: We offered point-of-care (POC) testing for HCV and immediate HCV-treatment to people who inject drugs (PWID) in a mobile clinic in the centre of Oslo. Aims: To compare HCV-treatment uptake among users of the clinic who were either screened for anti-HCV-antibodies prior to HCV-RNA-testing, or immediately tested for HCV-RNA without prior screening.
Design: Prospective, non-randomised controlled study. Methods: POC HCV-RNA-testing was performed on capillary blood (GeneXpert® HCV Viral Load) in a mobile outreach clinic for PWID in Oslo. Period A: users were first screened for anti-HCV antibodies with an oral swab (OraQuick®). Those who were antibody positive were offered immediate POC HCVRNA-testing. Period B: users received immediate POC HCV-RNA-testing. Patients who were HCVRNA-positive were offered prompt pangenotypic DAA-treatment.
We included 98 participants, 48 in period A and 50 in period B. The median age was 38 years, 65% were male, 18% were previously treated for HCV-infection, 90% had recent (past 6 months) injecting drug use, 60% injected daily, and 35% received opioid agonist treatment. In period A, 27/48 (56%) were anti-HCV positive and 14/27 (52%) were lost to follow-up before POC HCV-RNA-test could be performed. HCV-RNA was detected in 4/13. In period B, 9/50 had detectable HCV-RNA. In period A, 3/48 (6,3%) initiated treatment, compared to 8/50 (16%) in period B (p=0.18).
In mobile HCV-clinics we recommend immediate POC HCV-RNA-testing instead of POC anti-HCV screening followed by POC HCV-RNA-testing.
