Elbasvir–Grazoprevir Is Effective in HCV-Infected Patients Who Abuse Drugs

Although current hepatitis C virus (HCV) regimens are safe and highly effective, even among difficult-to-treat populations, their efficacy is unknown among marginalized populations like injection drug users.

In an industry-funded, randomized, controlled trial, researchers evaluated the efficacy of once-daily elbasvir–grazoprevir in patients with HCV genotype 1, 4, or 6 who had been receiving opioid-agonist therapy with methadone, buprenorphine, or buprenorphine–naloxone for ≥3 months and had ≥80% adherence to therapy appointments. Ongoing illicit drug use was not an exclusion criterion. Patients were randomized in a 2:1 ratio to immediate treatment (201 patients) or deferred treatment (placebo for 12 weeks followed by open-label treatment with elbasvir–grazoprevir; 100 patients). The primary outcome was sustained virologic response at 12 weeks after treatment completion (SVR12), and long-term SVR and reinfection rates were assessed through 2 years posttreatment.

The SVR12 rate was 91.5% in the immediate-treatment group and 89.5% in the deferred-treatment group. Among the 17 patients who did not achieve SVR12, failure was attributed to nonvirologic reasons (e.g., loss to follow-up) in 5. In the other 12 participants, sequencing and phylogenetic mapping suggested causes of viral relapse in 7 and likely reinfection in 5. More than half of all patients had consistently positive drug screens during the treatment period, but ongoing illicit drug use did not affect adherence or efficacy.