Potential drug-drug interactions between antiretroviral drugs and comedications, including dietary supplements, among people living with HIV: A clinical survey

Therapeutic drug monitoring of antiretroviral therapy: current progresses and future directions

INTRODUCTION

The treatment of HIV infection has been revolutionized in recent years thanks to the advent of dual antiretroviral regimens, administered orally or as long-acting injectable formulations. Here, we provide an update on the usefulness of therapeutic drug monitoring (TDM) of antiretroviral drugs to optimize the management of people with HIV (PWH) in the current scenario.

AREAS COVERED

A MEDLINE PubMed search for articles published between January 2014 and January 2024 was completed matching the terms HIV, antiretrovirals and TDM. Moreover, additional studies were identified from the reference list of retrieved articles.

EXPERT OPINION

Available antiretroviral treatments achieve a response rate of 90%-95%, making the routine TDM of antiretroviral drugs of limited clinical value. However, there are still some important applications of TDM in selected clinical conditions, such as assessing patient compliance or suspected drug-drug interactions (DDIs). Indeed, we are increasingly having to deal with polypharmacy and DDIs in the context of an aging patient with comorbidities that may potentially alter the pharmacokinetics of antiretroviral drugs. Finally, the role of pharmacogenetics, which is closely related to TDM, in influencing both the disposition of antiretrovirals and the course of DDIs should also be considered.

An update on drug-drug interactions in older adults living with human immunodeficiency virus (HIV)

INTRODUCTION

People with HIV are living longer due to advances in antiretroviral therapy. With improved life expectancy comes an increased lifetime risk of comorbid conditions - such as cardiovascular disease and cancer - and polypharmacy. Older adults, particularly those living with HIV, are more vulnerable to drug interactions and adverse effects, resulting in negative health outcomes.

AREA COVERED

Antiretrovirals are involved in many potential drug interactions with medications used to treat common comorbidities and geriatric conditions in an aging population of people with HIV. We review the mechanisms and management of significant drug-drug interactions involving antiretroviral medications and non-antiretroviral medications commonly used among older people living with HIV. The management of these interactions may require dose adjustments, medication switches to alternatives, enhanced monitoring, and considerations of patient- and disease-specific factors.

EXPERT OPINION

Clinicians managing comorbid conditions among older people with HIV must be particularly vigilant to side effect profiles, drug-drug interactions, pill burden, and cost when optimizing treatment. To support healthier aging among people living with HIV, there is a growing need for antiretroviral stewardship, multidisciplinary care models, and advances that promote insight into the correlations between an individual, their conditions, and their medications.

Outcomes of Drug Interactions Between Antiretrovirals and Co-Medications, Including Over-the-Counter Drugs: A Real-World Study

INTRODUCTION

The objective was to characterize real-world outcomes of drug-drug interactions (DDIs) between antiretrovirals (ARVs) and other drugs, including over-the-counter medications (OTC), and treatment outcomes in clinical practice.

METHODS

www.clinicalcasesDDIs.com is an open-access website for healthcare providers to consult and briefly describe real-world clinical cases on DDI with ARVs. We reviewed all the clinical cases reported to the website between March 2019 and May 2023.

RESULTS

A total of 139 cases were reported, mostly involving ritonavir or cobicistat (boosters; 74 cases), unboosted integrase inhibitors (InSTI; 29 cases), and non-nucleoside reverse transcriptase inhibitors (NNRTI; 23 cases). Central nervous system drugs (29 cases) and cardiovascular drugs (19 cases) were the most frequently described co-medications. Notably, OTC medications were implicated in 27 cases, including mineral supplements (11 cases), herbals (8 cases), weight loss drugs (4 cases), anabolic steroids (3 cases), and recreational drugs (1 case). OTC acted as the perpetrator drug in 21 cases, leading to loss of ARV efficacy in 17 instances (mineral supplements in 10 cases, weight loss drugs in 4 cases, herbals in 3 cases). Additionally, toxicity was reported in 4 out of 6 cases where OTC was considered the victim drug of the DDI (anabolic steroids in 3 cases, MDMA in 1 case).

CONCLUSIONS

Frequent unwanted outcomes resulting from DDIs between ARVs and OTC medications underscore the importance of integrating non-prescription drugs into medication reconciliation. The real-world data available through www.clinicalcasesDDIs.com serves as a valuable resource for assessing the clinical relevance of DDIs.

Polypharmacy and Aging in People Living with HIV: 6 Years of Experience in a Multidisciplinary Outpatient Clinic

BACKGROUND

Despite the availability of potent antiretroviral drugs, the management of human immunodeficiency virus (HIV) infection still presents some important challenges, especially in older patients who often experience age-related comorbidities and complex polypharmacy.

OBJECTIVE

To describe the results of our 6 year experience with the outpatient clinic [Gestione Ambulatoriale Politerapie (GAP)] for the management of polypharmacy in people living with HIV (PLWH).

METHODS

Demographic characteristics, antiretroviral regimens, and number and type of comedications were collected in all PLWH included in the database of GAP from September 2016 to September 2022. Therapies were stratified based on the number of anti-HIV drugs (dual versus triple regimens) and on the presence of pharmacokinetic boosters (ritonavir or cobicistat).

RESULTS

A total of 556 PLWH were included in the GAP database. Overall, the enrolled patients were administered 4.2 ± 2.7 drugs (range 1-17) in addition to antiretroviral therapies. The number of comedications greatly increased with age (3.0 ± 2.2 versus 4.1 ± 2.5 versus 6.3 ± 3.2 in PLWH aged < 50 versus 50-64 versus > 65 years; p < 0.001 for all comparisons). PLWH on dual antiretroviral therapies were significantly older (58 ± 9 versus 54 ± 11 years; p < 0.001) and were concomitantly treated with more drugs (5.1 ± 3.2 versus 3.8 ± 2.5; p < 0.001) compared with those on triple therapies. A significant reduction of boosted antiretroviral regimens (53% versus 23%; p < 0.001) and in the number of comedications (4.0 ± 2.9 versus 3.1 ± 2.2 drugs; p < 0.001) was observed in the subgroup of patients (n = 198) with two GAP visits.

CONCLUSIONS

The high prevalence of polypharmacy in PLWH, especially among older adults, place these patients at high risk for clinically relevant drug-drug interactions (DDIs). A multidisciplinary approach involving physicians and clinical pharmacologists could help to optimize medication regimens associated with reduced risk.

Potential drug-drug interactions due to concomitant medicine use among people living with HIV on antiretroviral therapy in Australia

AIMS

We quantified concomitant medicine use and occurrence of potential drug-drug interactions in people living with HIV in Australia who are treated with antiretroviral therapy (ART).

METHODS

In this cohort study using dispensing claims of a 10% random sample of Australians, we identified 2230 people dispensed ART between January 2018 and December 2019 (mean age 49.0 years, standard deviation 12.0 years, 88% male). We examined concomitant medicine use by identifying nontopical medicines dispensed within 90-days of any antiretroviral medicine dispensing during a 12-month follow-up period. For every antiretroviral and nonantiretroviral pair, we identified and classified possible drug-drug interactions using the University of Liverpool HIV drug interactions database.

RESULTS

A total of 1728 (78%) people were dispensed at least 1 and 633 (28%) 5 or more unique medicines in addition to ART in a 12-month period; systemic anti-infectives and medicines acting on the nervous system were the most common (68% and 56%, respectively). Among comedicated people, 1637 (95%) had at least 1 medicine combination classified as weak interactions, 558 (32%) interactions requiring close monitoring/dose adjustment and 94 (5%) that should not be coadministered. Contraindication or interactions requiring close monitoring/dose adjustment were more common among people receiving protease inhibitors (50-73% across different antiretrovirals), non-nucleoside reverse transcriptase inhibitors (35-64%), people using single-tablet combinations containing elvitegravir (30-46%) and those using tenofovir disoproxil (26-30%).

CONCLUSION

Concomitant medicine use is widespread among people living with HIV in Australia. Despite a relatively low prevalence of contraindicated medicines, almost a third received medicines that require close monitoring or dose adjustment.

Pharmacist-Involved Antiretroviral Stewardship Programs in People Living with HIV/AIDS: A Systematic Review

People living with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS; PLWHA) frequently encounter antiretroviral (ARV) therapy-related problems. Clinical pharmacists with specialized training in ARV stewardship play an important role in managing these problems. However, there is a paucity of evidence to clarify the impact of clinical pharmacists' interventions on managing ARV therapy-related problems in PLWHA. Therefore, we aim to systematically review the literature to determine the nature and impact of pharmacists' interventions on managing medication-related problems in PLWHA. The review protocol was registered on International Prospective Register of Systematic Reviews (PROSPERO; CRD42020173078). Relevant records were identified from six electronic bibliographic databases (PubMed, Embase, EBSCOhost, ProQuest, Scopus, and the Cochrane Central Register) from their inception until September 2022. We included all randomized and nonrandomized interventional studies that were published in English. After the abstract and full-text screening, data were extracted from the selected studies, and the quality of the studies was assessed. The electronic database search and citation tracking identified two thousand and three citations. The review included 21 of these studies, involving 2998 PLWHA, published between 2014 and 2022. Pharmacists' interventions, working alone or in a multi-disciplinary team, comprised ARV medication review, management of adverse drug reactions (ADRs), therapeutic drug monitoring, prevention of drug interactions, and provision of drug information to PLWHA or the health care team. The pharmacist-involved interventions significantly reduced incorrect/incomplete ARV regimens, drug interactions, incorrect dosages, duplicate therapy, polypharmacy, administration errors, missing medication, wrong formulation, ADRs, and prescribing errors. Most studies reported that physicians usually accept more than 90% of the pharmacists' recommendations. ARV medication-related problems remain highly prevalent in PLWHA. Pharmacist-led interventions and stewardship significantly reduce ARV therapy-related problems in PLWHA and are widely accepted by physicians. Dedicated pharmacists with specialized training and credentialing in infectious diseases or HIV/AIDS have a great potential to improve health outcomes in PLWHA.