Theme: Clinical Research Year: 2015
Introduction: Adherence is associated with sustained virological response (SVR). This study assessed adherence and completion of response-guided pegylated interferon alfa-2a (PEG-IFN) and ribavirin (RBV) therapy among people with recent HCV infection.
Methods: Participants enrolled in the ATAHC II (PEG-IFN +/- RBV) and DARE-C I [PEG-IFN/RBV/telaprevir (TVR)] studies were included. Treatment duration was response-guided (ATAHC II: 8, 16, 24 or 48 weeks; DARE-C I: 8, 12 or 24 weeks). PEG-IFN and RBV adherence were assessed by 80/80 (≥80% of doses, ≥80% treatment duration) and 100/100 adherence, on-treatment adherence and treatment completion. Logistic regression analyses were used to identify predictors of adherence. PEG-IFN 80/80 adherence and treatment completion were compared with ATAHC I (n=109, PEG-IFN +/- RBV for 24 weeks).
Results: 66 participants (94% male, 72% HIV; 59% had injected drugs ever) received treatment (PEG-IFN, n=1; PEG-IFN/RBV, n=51; PEG-IFN/RBV/TVR, n=14). Median treatment duration was 14 weeks (IQR 8-16). Early treatment discontinuation occurred in 18% (virological failure, 11% [n=7]; medical contraindication to continuation, 1% [n=1], clinician decision to cease, 5% [n=3]; participant unwilling to continue, 1% [n=1]). PEG-IFN 80/80 and 100/100 adherence were 100% and 98% (mean on-treatment adherence=99.9%). PEG-IFN 80/80 adherence was higher in ATAHC II/DARE-C I participants compared with ATAHC I (100% vs 82%, p<0.001). RBV 80/80 and 100/100 adherence were 95% and 63% (mean on-treatment adherence=96.0%). RBV 80/80 adherence was higher in those with HCV/HIV (100% vs 82%, p=0.003). RBV adherence was not associated with SVR12. In adjusted analysis, <100/100 RBV adherence was associated with lower social functioning (AOR 0.23, 95% CI 0.06-0.84, p=0.026) and longer treatment duration (AOR 0.44, 95% CI 0.23-0.85, p=0.014), but not injecting drug use. Conclusion: Treatment adherence was high in participants receiving short duration response-guided therapy. Failure to achieve SVR was due to treatment discontinuation as opposed to non-adherence.Download abstract