HCV reinfection and injecting risk behavior following elbasvir/grazoprevir treatment in patients on opioid agonist therapy: Co-STAR Three Year Follow-up Study

Jason Grebely, Gregory Dore, Frederick Altice, Alain Litwin, Olav Dalgard, Edward Gane, Oren Shibolet, Anne Luetkemeyer, Ronald Nahass, Cheng-Yuan Peng, Brian Conway, David Iser, Hsueh-cheng Huang, Isaias Gendrano, Michelle Kelly, Peggy Hwang, Michael Robertson, Janice Wahl, Eliav Barr, Heather Platt

Aims: The aim of the Co-STAR Three Year Follow-up Study (3YFU) is to evaluate HCV reinfection and injecting risk behaviors in patients on opioid agonist therapy (OAT) treated with elbasvir/grazoprevir for 12 weeks.

Methods: This 3 year observational cohort study enrolled patients who received at least one dose of elbasvir/grazoprevir in the Phase 3 trial. Every 6 months, patients are tested for HCV RNA and if detected, viral genotype and sequencing are performed. Patients complete a questionnaire to assess drug use.

Results: Of 296 treated in Co-STAR, 185 patients (63%) were enrolled in the 3YFU (mean age 49, 76% male). Median time from EOT to the first visit during the 3YFU was 330 days (range: 206-485). In addition to 6 reinfections observed between EOT and follow-up week 24, two viral recurrences were identified at the first visit in the 3YFU. One patient had GT1a at baseline: the patient reported non-injection drug use at follow-up, GT3 was identified, and opioids and cannabinoids were detected by UDS. One patient had GT1b at baseline, had HCV RNA (258 IU/mL) detected at the first visit (genotype could not be determined due to low viral load), but no drug use was reported by the patient for the previous 6 months, and no drugs besides OAT were detected by UDS; this patient is not considered a reinfection. In the 3YFU, 58% (105/185) reported any drug use (non-injecting/injecting) in the past 6 months. Injecting drug use in the past 6 months was reported by 47 (25%) patients. Among those reporting injecting drug use in the past 6 months (n=47 patients), injected drugs included heroin (n=34; 72%), amphetamines (n=8; 17%), cocaine (n=7; 15%), and other opioids (n=7; 15%).

Conclusion: HCV reinfection among patients on opioid agonist therapy following elbasvir/grazoprevir treatment is uncommon despite ongoing drug use.