Background: Directly acting antivirals (DAA) against hepatitis C virus (HCV) infection have facilitated sustained virologic response (SVR) rates >90% in clinical studies. Yet, real life data regarding DAA treatment in people who inject drugs (PWIDs) are scarce. We evaluated the effectiveness of glecaprevir/pibrentasvir (G/P) in difficult-to-treat PWIDs with presumed high risk of non-adherence to DAA therapy using the concept of directly observed therapy involving their opioid substitution therapy (OST) facility.
Methods: N = 145 patients (m/f: 91/54; median age: 41.1 (IQR 19.5) years; HCV-genotype (GT) 1/2/3/4: 82/1/56/5, GT3: 38.6%; cirrhosis: n = 6; 4.1%) treated with G/P were included. PWIDs at high risk for non-adherence to DAA therapy received HCV treatment together with their OST under the supervision of medical staff ("directly observed therapy", DOT). The effectiveness of G/P given as DOT in PWIDs with presumed high risk of non-adherence to DAA therapy was compared to patients with suspected "excellent compliance" in the "standard setting" (SS) of G/P prescription at a tertiary care center and self-managed G/P intake at home. Treatment duration was 8-16 weeks according to the G/P drug label.
Results: DOT-patients (n = 74/145; 51.0%) were younger than SS-patients (median 38.7, IQR 12.5 vs. median 50.6, IQR 20.3 years), all had psychiatric co-morbidities and most had a poor socioeconomic status. 50/74 (67.6%) reported ongoing intravenous drug use (IDU). SVR was achieved in n = 70/74 (94.6%) patients with n = 3 being lost to follow-up (FU) and n = 1 showing nonresponse to therapy. SS-patients achieved SVR in 97.2% (69/71) with n = 1 patient being lost to FU and n = 1 patient with GT3 showing HCV relapse.
Conclusion: G/P given as DOT along with OST in PWIDs with high risk of non-adherence to DAA therapy resulted in similarly high SVR rates (94.6%) as in patients with presumed "excellent compliance" under standard drug intake.