Prevalence of Potentially Clinically Significant Drug-Drug Interactions With Antiretrovirals Against HIV Over Three Decades: A Systematic Review of the Literature

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.

Management of the Drug-Drug Interactions Between Valproic Acid and Dolutegravir-A Case Study

OBJECTIVE

Preliminary evidence shows that concomitant administration of valproic acid can reduce the exposure to dolutegravir with limited clinical impacts. Here, we describe a male living with HIV who experienced a drastic reduction in dolutegravir trough concentrations a few weeks after starting valproic acid treatment as identified by therapeutic drug monitoring. Concomitantly, pharmacists recommended a supplementation of magnesium to improve insomnia.

CASE REPORT

A 62-year-old man with HIV on antiretroviral therapy with dolutegravir and lamivudine recently added valproic acid to clonazepam and sertraline to treat severe sleep disturbances. An 84% reduction in dolutegravir trough concentrations was observed compared with the previous outpatient visit (418 versus 2714 ng/mL), with values close to the minimum effective drug concentration (300 ng/mL). Considering this, we strongly discourage the use of magnesium.

CONCLUSIONS

We are confident that our findings can contribute to a better understanding of the clinical problems that infectious disease physicians encounter in their daily management of people with HIV and how therapeutic drug monitoring may add value in this context. This case also highlights the importance of multidisciplinary services for the optimal management of polypharmacy in people with HIV.

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 potential drug-drug interactions among people living with HIV in the era of integrase strand transfer inhibitor-based antiretroviral therapy

OBJECTIVES

To investigate the prevalence of polypharmacy and potential drug-drug interactions (DDIs), and the factors associated with DDIs among people living with human immunodeficiency virus (HIV; PLWH) in the modern era of antiretroviral therapy (ART).

METHODS

This cross-sectional study included PLWH who had been on ART for ≥3 months at two designated HIV hospitals in Taiwan. All ART and non-ART prescriptions were collected from the NHI-MediCloud System and screened for DDIs using the University of Liverpool HIV drug interactions database. A case-control analysis was conducted to investigate the factors associated with DDIs.

RESULTS

In total, 1007 PLWH were included in this study from June 2021 to August 2022. The median age was 40 (interquartile range 33-49) years, and 96.2% were taking integrase strand transfer inhibitor (INSTI)-based ART. The proportions of PLWH with at least one non-communicable disease and polypharmacy were 50.0% and 18.7%, respectively. Seven (0.7%) PLWH had red-flagged DDIs, and 159 (15.8%) had amber-flagged DDIs. In multi-variable models, the prevalence of DDIs was associated with older age [adjusted odds ratio (aOR) per 1-year increase 1.022), number of co-medications (aOR 1.097), use of boosted INSTI-based ART (vs unboosted INSTI, aOR 8.653), and concomitant medications in the alimentary tract and metabolism category (aOR 11.058) and anti-neoplastic and immunomodulating agents (aOR 14.733).

CONCLUSIONS

In the INSTI era, the prevalence of potential DDIs is lower than noted previously, but remains substantial. Clinicians should monitor DDIs routinely, especially in older PLWH, those taking a higher number of co-medications, and those who are taking booster-containing ART or medications from specific categories.

Molecular Factors and Pathways of Hepatotoxicity Associated with HIV/SARS-CoV-2 Protease Inhibitors

Antiviral protease inhibitors are peptidomimetic molecules that block the active catalytic center of viral proteases and, thereby, prevent the cleavage of viral polyprotein precursors into maturation. They continue to be a key class of antiviral drugs that can be used either as boosters for other classes of antivirals or as major components of current regimens in therapies for the treatment of infections with human immunodeficiency virus (HIV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, sustained/lifelong treatment with the drugs or drugs combined with other substance(s) often leads to severe hepatic side effects such as lipid abnormalities, insulin resistance, and hepatotoxicity. The underlying pathogenic mechanisms are not fully known and are under continuous investigation. This review focuses on the general as well as specific molecular mechanisms of the protease inhibitor-induced hepatotoxicity involving transporter proteins, apolipoprotein B, cytochrome P450 isozymes, insulin-receptor substrate 1, Akt/PKB signaling, lipogenic factors, UDP-glucuronosyltransferase, pregnane X receptor, hepatocyte nuclear factor 4α, reactive oxygen species, inflammatory cytokines, off-target proteases, and small GTPase Rab proteins related to ER-Golgi trafficking, organelle stress, and liver injury. Potential pharmaceutical/therapeutic solutions to antiviral drug-induced hepatic side effects are also discussed.