Brief Report: High Need to Switch cART or Comedication with the Initiation of DAAs in Elderly HIV/HCV-Coinfected Patients

Background: To describe the use of nonantiretroviral comedication and combination antiretroviral therapy (cART) in patients coinfected with HIV/hepatitis C virus (HCV) and to predict the potential for drug-drug interactions (DDIs) with direct-acting antivirals (DAAs) against HCV. Methods: This is a retrospective, cross-sectional study, using the Dutch, nationwide ATHENA observational HIV cohort database. All patients with a known HIV/HCV coinfection on January 1, 2015, were included. Comedication and cART registered in the database were listed. The potential for DDIs between DAAs and comedication/cART were predicted using http://hep-druginteractions.org. DDIs were categorized as: (1) no clinically relevant DDI; (2) possible DDI; (3) contraindication; or (4) no information available. Results: We included 777 patients of whom 488 (63%) used nonantiretroviral comedication. At risk for a category 2/3 DDI with nonantiretroviral comedications were 299 patients (38%). Most DDIs were predicted with paritaprevir/ritonavir, ombitasvir ± dasabuvir (47% of the drugs) and least with grazoprevir/elbasvir (11% of the drugs). Concerning cART, daclatasvir/sofosbuvir is the most favorable combination as no cART is contraindicated with this combination. In genotype 1/4 patients, grazoprevir/elbasvir is least favorable as 75% of the patients must alter their cART. Conclusions: This study showed that comedication use in the aging HIV/HCV population is frequent and diverse. There is a high potential for DDIs between DAAs and comedication/cART.