by Jeffrey T. Kirchner, DO, AAHIVS, AAHIVM Chief Medical Officer

November 24, 2020

Featured Literature:

El Moussaou, M et al. Evolution of drug Interactions with antiretroviral medication in people with HIV. Open Forum Infectious Diseases, Volume 7, Issue 11, November 2020.

The average age of persons with HIV (PWH) continues to increase. The aging of this population results in comorbidities which require medical therapy along with prescribed ART – thus creating the potential for drug-drug interactions. This paper from Belgium included 1,038 PWH cared for at a university clinic during 2012 and 2016. Data regarding their medication use was collected and analyzed with the University of Liverpool HIV database. In this database, drug-drug interactions are classified as “red flag” (contraindicated) and “orange flag” (potential dose adjustment and/or timing of administration and/or close monitoring required) interactions. Among the entire cohort, 78% were taking at least one additional medication besides ART and 20% were taking five or more concurrent medications. The authors found the percentage of PWH receiving medications causing at least one RED flag interaction was similar over time – 4.7% in 2012 and 4.8% in 2016. Regarding ORANGE flag interactions, the percentages were 41% and 43% respectively during this time. The most common classes of medications involved with drug interactions were CNS and CVD drugs, followed by hormonal therapies and dietary supplements. The 2016 analysis mainly found interactions between calcium-containing products and integrase inhibitors (INIs). Two factors that significantly contributed to the number of interactions included the total number of non-HIV therapies and the use of protease inhibitors (PIs). Despite the progressive change in first-line therapies away from PIs to INIs, this study found a persistence of drug-drug interactions in PWH over time.

Author’s Commentary:

Drug-drug interactions have been a concern since the use of protease inhibitors in the mid 1990s. These interactions can result in toxic drug levels or reduction in ARV levels leading to treatment failure and resistance. Simplification and expansion of ART, especially with integrase inhibitors have seemingly made drug interactions less common. However, as this study found, many PWH are taking multiple drugs besides ART. A large percentage also take OTC or alternative therapies. It is prudent to review ALL medications with PWH at every clinic visit and consider utilizing a clinical pharmacist who can also review the patient’s medication list. Identification, prevention and management of drug interactions remain a key priority in HIV care. The Liverpool HIV database can be accessed at

The author has no conflicts of interest to disclose.

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