Drug Interactions Are Manageable in Older Adults With HIV
Polypharmacy is more prevalent among individuals with HIV, especially those who are aged 50 years or older. Therefore, it is important for health care providers to understand the mechanisms of drug-drug interactions, the difference in drug-drug interaction potential of currently recommended antiretroviral therapies, and the clinical relevance of drug-drug interactions.
This was the topic of Thursday’s Plenary Session at the Conference on Retroviruses and Opportunistic Infections 2019. David Blast, from the University of Liverpool in the United Kingdom, presented “The Challenges of HIV Treatment in an Era of Polypharmacy.”
Blast started his lecture by explaining the research that has shed light on the prevalence of comorbidities and other age-related conditions in individuals with HIV.
“Here we can see multiple studies in the last 12 months, which have shown us that the prevalence of polypharmacy is in the region of 30% to 50%,” Blast said.
“We live in an age of multi-morbidity, particularly in our older HIV patients. This leads to polypharmacy and sometimes polydoctory, leading to an increase in pill burden, a decrease in medication adherence, and an increase of prescribing cascade error. But at the center, we’re looking at drug interactions and the potential of an interaction to be clinically relevant,” Blast said.
Then Blast discussed how to evaluate the interaction potential of a drug. In preclinical studies, there will be an understanding of whether the drug is a perpetrator or a victim of drug interactions. Phase 1 and 2 studies will focus on phamarcokinetics and drug interactions, using plausible mechanisms and potential comedications in the target population.
In terms of which antiretrovirals are most risky, Blast said raltegravir, dolutegravir, bictegravir, efavirenz, etravirine, rilpivirine, and doravirine all have interactions. However, raltegravir and dolutegravir have the least amount of interactions overall.
“DDIs are practically unavoidable in HIV care, but they are mostly manageable. Older patients are particularly at risk for age-related comorbidities and physiological changes. And searchable online drug-drug interaction checkers are a vital resource,” Blast concluded.
—Amanda Balbi
Reference:
Back D. The challenges of HIV treatment in an era of polypharmacy. Session presented at: Conference on Retroviruses and Opportunistic Infections 2019; March 4-7, 2019; Seattle, WA. http://www.croiconference.org/sessions/challenges-hiv-treatment-era-polypharmacy. Accessed March 8, 2019.