Selection of an appropriate antiretroviral regimen for the patient infected with human immunodeficiency virus can be challenging, as various considerations must be taken into account including viral resistance mutations, patient comorbidities, drug interactions, and the potential for drug-related adverse effects and toxicities. Treatment is further complicated when a clinical scenario arises requiring an alteration in the dosage form. Factors ranging from dysphagia to administration through an enteral feeding tube can affect decisions regarding antiretroviral dosage forms. Limited pharmacokinetic data exist regarding the alteration of antiretroviral medications from their original form. Bioavailability may vary substantially between dosage forms, which can lead to unpredictable drug concentrations. Supratherapeutic or subtherapeutic antiretroviral drug concentrations can result in increased toxicity, virologic failure, or the emergence of drug resistance. We performed a systematic literature search to review the available antiretroviral literature on the modification of solid dosage forms as well as alternative routes of administration of oral antiretroviral agents and their application to clinical practice.

Fidaxomicin is a well-tolerated agent for the treatment of CDI and has been shown to be noninferior to vancomycin in the management of mild-to-moderately severe CDI.

Background Switching antiretroviral therapy (ART) in people with HIV (PWH) can influence their risk for drug–drug interactions (DDIs). The purpose of this study was to assess changes in the incidence and severity of DDIs among PWH who switched their ART to bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF). Methods This was a multicenter retrospective cohort study of PWH on ART and at least 1 concomitant medication (CM) who switched to BIC/FTC/TAF between 3/2018 and 6/2019. Using the University of Liverpool’s HIV Drug Interaction Database, 2 DDI analyses were performed for each patient. The first assessed patients’ preswitch ART regimens with their CM list. The second assessed the same CM list with BIC/FTC/TAF. Each ART-CM combination was given a score of 0 (no or potential weak interaction), 1 (potential interaction), or 2 (contraindicated interaction). A paired t test analyzed changes in total DDI scores following ART switches, and linear regression examined factors contributing to DDI score reductions. Results Among 411 patients, 236 (57%) had at least 1 DDI present at baseline. On average, baseline DDI scores (SD) were 1.4 (1.8) and decreased by 1 point (95% CI, –1.1 to –0.8) after patients switched to BIC/FTC/TAF (P < .0001). After adjusting for demographics, baseline ART, and CM categories, switching to BIC/FTC/TAF led to significant DDI score reductions in patients receiving CMs for cardiovascular disease, neurologic/psychiatric disorders, chronic pain, inflammation, gastrointestinal/urologic conditions, and conditions requiring hormonal therapy. Conclusions Treatment-experienced PWH eligible to switch their ART may experience significant declines in number and severity of DDIs if switched to BIC/FTC/TAF.

Highly active antiretroviral therapy (ART) and its widespread availability have revolutionized the landscape of HIV care and patient outcomes, transforming infection with HIV into a manageable chronic condition rather than a life-limiting disease. This transformation has created an older patient demographic. The effect that older age has on the outcomes of ART is not completely understood. Limited data are available in older individuals due to underrepresentation in clinical trials. To better understand this relationship, we conducted a literature search to assess the impact of older age on the outcomes of ART in the older HIV-infected population, including immunologic and virologic outcomes, mortality, disease progression, toxicity of ART, and pharmacokinetic considerations. In addition, package inserts of antiretroviral (ARV) medications were reviewed for efficacy, safety, and pharmacokinetic information pertaining to the older population. Most studies in older adults (50 yrs or older) demonstrated slower and blunted CD4 immune recovery but better virologic suppression in response to ART. Higher rates of mortality and faster disease progression have been observed in adults 50 years and older, particularly during the first year after ART initiation. HIV-infected patients aged 50 years and older appear to be at greater risk for certain ART-associated toxicities including nephrotoxicity, decline in bone mineral density and bone fracture, symptomatic peripheral neuropathy, and cardiovascular disease including myocardial infarction. The available literature suggests that clinicians should consider avoiding agents such as tenofovir disoproxil fumarate (TDF) in older patients with risk factors for renal impairment and/or osteoporosis. If TDF is used in patients aged 50 years or older, more frequent monitoring should be considered. Older age was a significant predictor for higher atazanavir exposure and higher lopinavir trough concentration at 24 weeks. The clinical implications of these findings are unknown. It is imperative that future development of novel ARV drug therapies includes a greater proportion of older subjects in clinical trials.