High frequency of potential interactions between direct-acting antivirals and concomitant therapy in HIV/hepatitis C virus-coinfected patients in clinical practice

Objectives The aim of the study was to analyse the frequency and degree of potential drug-drug interactions (DDIs) between direct-acting antivirals (DAAs) and concomitant medication used by HIV/hepatitis C virus (HCV)-coinfected patients, including antiretroviral therapy (ART) and other drugs. Methods All patients with HIV infection and viraemic HCV genotype 1, 3 or 4 coinfection attending a tertiary care centre in Spain (November 2014 to November 2015) were included in the study. DDIs were classified as major, i.e. drugs should not be co-administered, or minor, i.e. close monitoring, dosage alteration or change in timing may be required if drugs are co-administered, following the http://www.hep-druginteractions.org database recommendations. Results A total of 244 patients were included in the study, of whom 224 (92%) were previous injecting drug users. Major DDIs were found for: paritaprevir-r/ombitasvir plus dasabuvir (3D), in 60 (44%) of 138 individuals with genotype 1; paritaprevir-r/ombitasvir (2D), in 22 (37%) of 60 individuals with genotype 4; sofosbuvir/ledipasvir (SOF/LDV), in four (2%) of 198 patients with genotype 1 or 4; simeprevir (SMV) plus SOF, in 160 (81%) of 198 patients with genotype 1 or 4; daclatasvir (DCV) plus SOF, in seven (3%) of 244 patients with genotype 1, 3 or 4 (P < 0.001). Minor DDIs were found for: 3D, in 123 (89%) individuals with genotype 1; 2D, in 52 (87%) individuals with genotype 4; SOF/LDV, in 154 (78%) patients with genotype 1 or 4; SMV plus SOF, in 129 (65%) patients with genotype 1 or 4; DCV plus SOF, in 149 (61%) patients with genotype 1, 3 or 4 (P < 0.001). Conclusions Drug-drug interactions between DAAs and ART or other commonly prescribed medications are frequently found among HIV/HCV-coinfected patients. Potential major and minor DDIs are more frequent with 3D, 2D and SMV plus SOF regimens.