Impact of recent drug use on the efficacy of elbasvir/grazoprevir for HCV-infected people on opioid agonist therapy

Elbasvir/grazoprevir (EBR/GZR) use in drug users on opiate agonist therapy (OAT) is supported by the C-EDGE Co-STAR trial. SVR rates in this study were within those found in the rest of patients included by the EBR/GZR development programme. In clinical practice, however, efficacy could theoretically be lower. Thus, we aimed at evaluating the SVR rates of EBR/GZR among people who injected drugs (PWID) with and without OAT in clinical practice. Patients starting EBR/GZR included in the HEPAVIR-DAA (NCT02057003), recruiting HIV/HCV-coinfected patients or the GEHEP-MONO (NCT02333292), including HCV-monoinfected individuals, prospective cohorts were analysed. Overall SVR12 (ITT), discontinuations due to adverse effects and drop-outs were evaluated. The same analysis was carried out for PWID with and without OAT. 336 patients had started EBR/GZR and reached the SVR12 evaluation date. 318 [95%, 95% confidence interval (95% CI): 92%-98%] patients achieved SVR12. SVR12 was 97% (95% CI: 93%-99%, n/N = 141/145) among people who never used injecting drugs, 94% (95% CI: 88%-97%, n/N = 117/125) among PWIDs without OAT and 91% (95% CI: 81%-97%, n/N = 60/66) among PWIDs with OAT (p = 0.134). Five (1.5%) patients showed relapses, and two (0.6%) individuals showed viral breakthrough. The SVR12 rate for recent drug users was 69% (n/N = 18/26) compared with 97% (n/N = 276/284) for individuals without recent drug use (in the prior year) (p < 0.001). Among recent drug users, three (12%) showed relapses, and five (19%) were lost-to-follow-up. The SVR rates achieved with EBR/GZR were high in real-world conditions of use. However, PWID with recent drug use reach suboptimal response rates with EBR/GZR.