Results of a study of contraindicated concomitant medication use among recipients of preferred antiretroviral therapy (ART) regimens are reported.Methods.
A retrospective study was conducted to evaluate concomitant medication use in a cohort of previously treatment-naive, human immunodeficiency virus (HIV)–infected U.S. patients prescribed preferred ART regimens during the period April 2014–March 2015. Data were obtained from a proprietary longitudinal prescription database; elements retrieved included age, sex, and prescription data. The outcome of interest was the frequency of drug–drug interactions (DDIs) associated with concomitant use of contraindicated medications.Results.
Data on 25,919 unique treatment-naive patients who used a preferred ART regimen were collected. Overall, there were 384 instances in which a contraindicated medication was dispensed for concurrent use with a recommended ART regimen. Rates of contraindicated concomitant medication use differed significantly by ART regimen; the highest rate (3.2%) was for darunavir plus ritonavir plus emtricitabine–tenofovir disoproxil fumarate (DRV plus RTV plus FTC/TDF), followed by elvitegravir–cobicistat–emtricitabine–tenofovir disoproxil fumarate (EVG/c/FTC/TDF)(2.8%). The highest frequencies of DDIs were associated with ART regimens that included a pharmacoenhancing agent: DRV plus RTV plus FTC/TDF (3.2%) and EVG/c/FTC/TDF (2.8%).Conclusion.
In a large population of treatment-naive HIV-infected patients, ART regimens that contained a pharmacoenhancing agent were involved most frequently in contraindicated medication–related DDIs. All of the DDIs could have been avoided by using therapeutic alternatives within the same class not associated with a DDI.