Treatment duration affects adherence in HCV patients on glecaprevir/pibrentasvir

Post hoc analyses evaluating adherence based on pill count in patients prescribed 8- or 12-week glecaprevir/pibrentasvir (G/P) reveal that treatment duration influences adherence rates and further stress the concept of “treatment forgiveness” with direct-acting antiviral therapies.

In this study, the investigators pooled data from 10 phase III clinical trials of treatment-naïve patients with hepatitis C virus (HCV) genotype 1–6 with or without compensated cirrhosis (treatment adherence analysis) and 13 phase III clinical trials of all patients with HCV (interruption analysis).

A total of 2,149 patients were included, with an overall mean adherence of 99.4 percent. Adherence decreased (weeks 0–4: 100 percent; weeks 5–8: 98.3 percent; weeks 9–12 97.1 percent) and the percentage of patients with ≥80- or ≥90-percent adherence declined over the treatment duration.

In the intention-to-treat (ITT) population, sustained virologic response at post-treatment week 12 (SVR12) was 97.7 percent (modified ITT SVR12, 99.3 percent) and remained high in nonadherent patients in the modified ITT population (<90 percent: 94.4 percent to 100 percent; <80 percent: 83.3 percent to 100 percent).

Psychiatric disorders correlated with <80-percent adherence, while shorter treatment duration was associated with ≥80-percent adherence.

The interruption analysis revealed that 33 of 2,902 patients (1.1 percent) had a G/P treatment interruption of ≥1 day, with an SVR12 rate of 93.9 percent (31/33). Virologic failures did not occur.

“Pangenotypic, all-oral direct-acting antivirals, such as G/P, are recommended for treatment of HCV infection,” the investigators said. “Concerns exist about the impact on efficacy in patients with suboptimal adherence, particularly with shorter treatment durations.”