Effect of comedication on ombitasvir/paritaprevir/ritonavir ± dasabuvir ± ribavirin therapy in chronic hepatitis C – a real-world study

AIM OF THE STUDY: This multicentre study aimed to examine the actual risk for drug-drug interactions in a cohort of Polish patients, and their impact on antiviral therapy. MATERIAL AND METHODS: Concomitant medications were analyzed in hepatitis C virus (HCV)-infected patients treated with still valuable therapy with OBV/PTV/r ± DSV ± RBV. An established online tool (http://www.hep-druginteractions.org/) was used to assess potential drug interactions. To assess the impact of comedications on virologic outcomes, HCV RNA levels were measured at given time points during and after the treatment. The results were compared between subgroups depending on the number of drugs used. RESULTS: Among the 209 patients included in this multicentre study, concomitant medications were taken by 140 (67.0%) patients. Modification of treatment due to expected interactions was required in 33 (15.8%) patients, of whom nine (4.3%) had at least one comedication replaced or discontinued. Sustained virologic response rates ranged from 95.1% to 100.0%, and were lowest in patients taking one to five comedications who were null-responders to pegylated interferon or cirrhotic. CONCLUSIONS: Although most HCV-infected patients received concomitant medications, only some required treatment modification. OBV/PTV/r ± DSV ± RBV was effective in all subgroups, irrespective of the number of comedications taken. Multimorbidity and polypharmacy in patients with chronic hepatitis C should not discourage the decision to initiate antiviral therapy, although caution should be exercised for potential drug-drug interactions.