Pharmacokinetic Drug–Drug Interaction Study Between Raltegravir and Atorvastatin 20 mg in Healthy Volunteers

Real-life management of drug-drug interactions between antiretrovirals and statins

BACKGROUND

PIs cause drug-drug interactions (DDIs) with most statins due to inhibition of drug-metabolizing enzymes and/or the hepatic uptake transporter OATP1B1, which may alter the pharmacodynamic (PD) effect of statins.

OBJECTIVES

To assess the management of DDIs between antiretrovirals (ARVs) and statins in people living with HIV (PLWH) considering statin plasma concentrations, compliance with dosing recommendations and achievement of lipid targets.

METHODS

PLWH of the Swiss HIV Cohort Study were eligible if they received a statin concomitantly with ARVs. HDL, total cholesterol (TC) and statin plasma concentration were measured during follow-up visits. Individual non-HDL and TC target values were set using the Framingham score and the 2018 European AIDS Clinical Society recommendations.

RESULTS

Data were analysed for rosuvastatin (n = 99), atorvastatin (n = 92), pravastatin (n = 46) and pitavastatin (n = 21). Rosuvastatin and atorvastatin underdosing frequently led to suboptimal PD response. Insufficient lipid control was observed with PIs despite high atorvastatin concentrations, likely explained by inhibition of OATP1B1 resulting in less statin uptake in the liver. Target lipid values were more often achieved with unboosted integrase inhibitors due to both their favourable DDI profiles and neutral effect on lipids. Insufficient lipid control was common with pravastatin and pitavastatin regardless of co-administered ARVs and despite using maximal recommended statin doses. The latter suggests lower efficacy compared with rosuvastatin or atorvastatin.

CONCLUSIONS

Suboptimal management of DDIs with statin underdosing was observed in 29% of prescriptions. Integrase inhibitor-based regimens and/or treatment with rosuvastatin or atorvastatin should be favoured in patients with refractory dyslipidaemia.

A population pharmacokinetics analysis assessing the exposure of raltegravir once-daily 1200 mg in pregnant women living with HIV

Once-daily two 600 mg tablets (1200 mg q.d.) raltegravir offers an easier treatment option compared to the twice-daily regimen of one 400 mg tablet. No pharmacokinetic, efficacy, or safety data of the 1200 mg q.d. regimen have been reported in pregnant women to date as it is challenging to collect these clinical data. This study aimed to develop a population pharmacokinetic (PopPK) model to predict the pharmacokinetic profile of raltegravir 1200 mg q.d. in pregnant women and to discuss the expected pharmacodynamic properties of raltegravir 1200 mg q.d. during pregnancy based on previously reported concentration-effect relationships. Data from 11 pharmacokinetic studies were pooled (n = 221). A two-compartment model with first-order elimination and absorption through three sequential transit compartments best described the data. We assessed that the bio-availability of the 600 mg tablets was 21% higher as the 400 mg tablets, and the bio-availability in pregnant women was 49% lower. Monte-Carlo simulations were performed to predict the pharmacokinetic profile of 1200 mg q.d. in pregnant and nonpregnant women. The primary criteria for efficacy were that the lower bound of the 90% confidence interval (CI) of the concentration before next dose administration (C_trough ) geometric mean ratio (GMR) of simulated pregnant/nonpregnant women had to be greater than 0.75. The simulated raltegravir C_trough GMR (90% CI) was 0.51 (0.41-0.63), hence not meeting the primary target for efficacy. Clinical data from two pregnant women using 1200 mg q.d. raltegravir showed a similar C_trough ratio pregnant/nonpregnant. Our pharmacokinetic results support the current recommendation of not using the raltegravir 1200 mg q.d. regimen during pregnancy until more data on the exposure-response relationship becomes available.

Prediction of Cyclosporin-Mediated Drug Interaction Using Physiologically Based Pharmacokinetic Model Characterizing Interplay of Drug Transporters and Enzymes

Uptake transporter organic anion transporting polypeptides (OATPs), efflux transporters (P-gp, BCRP and MRP2) and cytochrome P450 enzymes (CYP450s) are widely expressed in the liver, intestine or kidney. They coordinately work to control drug disposition, termed as "interplay of transporters and enzymes". Cyclosporine A (CsA) is an inhibitor of OATPs, P-gp, MRP2, BCRP and CYP3As. Drug-drug interaction (DDI) of CsA with victim drugs occurs via disordering interplay of transporters and enzymes. We aimed to establish a whole-body physiologically-based pharmacokinetic (PBPK) model which predicts disposition of CsA and nine victim drugs including atorvastatin, cerivastatin, pravastatin, rosuvastatin, fluvastatin, simvastatin, lovastatin, repaglinide and bosentan, as well as drug-drug interactions (DDIs) of CsA with nine victim drugs to investigate the integrated effect of enzymes and transporters in liver, intestinal and kidney on drug disposition. Predictions were compared with observations. Most of the predictions were within 0.5-2.0 folds of observations. Atorvastatin was represented to investigate individual contributions of transporters and CYP3As to atorvastatin disposition and their integrated effect. The contributions to atorvastatin disposition were hepatic OATPs >> hepatic CYP3A > intestinal CYP3As ≈ efflux transporters (P-gp/BCRP/MRP2). The results got the conclusion that the developed PBPK model characterizing the interplay of enzymes and transporters was successfully applied to predict the pharmacokinetics of 10 OATP substrates and DDIs of CsA with 9 victim drugs.

An updated review of pharmacokinetic drug interactions and pharmacogenetics of statins

INTRODUCTION

Hydroxymethylglutaryl-coenzyme A reductase inhibitors (statins) lower cholesterol synthesis in patients with hypercholesterolemia. Increased statin exposure is an important risk factor for skeletal muscle toxicity. Potent inhibitors of cytochrome P450 (CYP) 3A4 significantly increase plasma concentrations of the active forms of simvastatin, lovastatin, and atorvastatin. Fluvastatin is metabolized by CYP2C9, whereas pravastatin, rosuvastatin, and pitavastatin are unaffected by inhibition by either CYP. Statins also have different affinities for membrane transporters involved in processes such as intestinal absorption, hepatic absorption, biliary excretion, and renal excretion.

AREAS COVERED

In this review, the pharmacokinetic aspects of drug-drug interactions with statins and genetic polymorphisms of CYPs and drug transporters involved in the pharmacokinetics of statins are discussed.

EXPERT OPINION

Understanding the mechanisms underlying statin interactions can help minimize drug interactions and reduce the adverse side effects caused by statins. Since recent studies have shown the involvement of drug transporters such as OATP and BCRP as well as CYPs in statin pharmacokinetics, further clinical studies focusing on the drug transporters are necessary. The establishment of biomarkers based on novel mechanisms, such as the leakage of microRNAs into the peripheral blood associated with the muscle toxicity, is important for the early detection of statin side effects.

HIV-Nef Protein Transfer to Endothelial Cells Requires Rac1 Activation and Leads to Endothelial Dysfunction Implications for Statin Treatment in HIV Patients

RATIONALE

Even in antiretroviral therapy-treated patients, HIV continues to play a pathogenic role in cardiovascular diseases. A possible cofactor may be persistence of the early HIV response gene Nef, which we have demonstrated recently to persist in the lungs of HIV+ patients on antiretroviral therapy. Previously, we have reported that HIV strains with Nef, but not Nef-deleted HIV strains, cause endothelial proinflammatory activation and apoptosis.

OBJECTIVE

To characterize mechanisms through which HIV-Nef leads to the development of cardiovascular diseases using ex vivo tissue culture approaches as well as interventional experiments in transgenic murine models.

METHODS AND RESULTS

Extracellular vesicles derived from both peripheral blood mononuclear cells and plasma from HIV+ patient blood samples induced human coronary artery endothelial cells dysfunction. Plasma-derived extracellular vesicles from antiretroviral therapy+ patients who were HIV-Nef+ induced significantly greater endothelial apoptosis compared with HIV-Nef-plasma extracellular vesicles. Both HIV-Nef expressing T cells and HIV-Nef-induced extracellular vesicles increased transfer of cytosol and Nef protein to endothelial monolayers in a Rac1-dependent manner, consequently leading to endothelial adhesion protein upregulation and apoptosis. HIV-Nef induced Rac1 activation also led to dsDNA breaks in endothelial colony forming cells, thereby resulting in endothelial colony forming cell premature senescence and endothelial nitric oxide synthase downregulation. These Rac1-dependent activities were characterized by NOX2-mediated reactive oxygen species production. Statin treatment equally inhibited Rac1 inhibition in preventing or reversing all HIV-Nef-induction abnormalities assessed. This was likely because of the ability of statins to block Rac1 prenylation as geranylgeranyl transferase inhibitors were effective in inhibiting HIV-Nef-induced reactive oxygen species formation. Finally, transgenic expression of HIV-Nef in endothelial cells in a murine model impaired endothelium-mediated aortic ring dilation, which was then reversed by 3-week treatment with 5 mg/kg atorvastatin.

CONCLUSIONS

These studies establish a mechanism by which HIV-Nef persistence despite antiretroviral therapy could contribute to ongoing HIV-related vascular dysfunction, which may then be ameliorated by statin treatment.

UHPLC-MS/MS assay for simultaneous determination of amlodipine, metoprolol, pravastatin, rosuvastatin, atorvastatin with its active metabolites in human plasma, for population-scale drug-drug interactions studies in people living with HIV

Thanks to highly active antiretroviral treatments, HIV infection is now considered as a chronic condition. Consequently, people living with HIV (PLWH) live longer and encounter more age-related chronic co-morbidities, notably cardiovascular diseases, leading to polypharmacy. As the management of drug-drug interactions (DDIs) constitutes a key aspect of the care of PLWH, the magnitude of pharmacokinetic DDIs between cardiovascular and anti-HIV drugs needs to be more thoroughly characterized. To that endeavour, an UHPLC-MS/MS bioanalytical method has been developed for the simultaneous determination in human plasma of amlodipine, metoprolol, pravastatin, rosuvastatin, atorvastatin and its active metabolites. Plasma samples were subjected to protein precipitation with methanol, followed by evaporation at room temperature under nitrogen of the supernatant, allowing to attain measurable plasma concentrations down to sub-nanogram per milliliter levels. Stable isotope-labelled analytes were used as internal standards. The five drugs and two metabolites were analyzed using a 6-min liquid chromatographic run coupled to electrospray triple quadrupole mass spectrometry detection. The method was validated over the clinically relevant concentrations ranging from 0.3 to 480 ng/mL for amlodipine, atorvastatin and p-OH-atorvastatin, and 0.4 to 480 ng/mL for pravastatin, 0.5 to 480 ng/mL for rosuvastatin and o-OH-atorvastatin, and 3 to 4800 ng/mL for metoprolol. Validation performances such as trueness (95.4-110.8%), repeatability (1.5-13.4%) and intermediate precision (3.6-14.5%) were in agreement with current international recommendations. Accuracy profiles (total error approach) were lying within the limits of ±30% accepted in bioanalysis. This rapid and robust UHPLC-MS/MS assay allows the simultaneous quantification in plasma of the major currently used cardiovascular drugs and offers an efficient analytical tool for clinical pharmacokinetics as well as DDIs studies.

Benefits and Risks of Statin Therapy in the HIV-Infected Population

PURPOSE OF REVIEW

HIV-infected patients face an increased risk for cardiovascular disease (CVD), estimated at 1.5- to 2-fold as compared to HIV-uninfected persons. This review provides a recent (within preceding 5 years) summary of the role of statin therapy and associated role in CVD risk reduction among HIV-infected patients on anti-retroviral therapy.

RECENT FINDINGS

Statins remain the preferred agents for reducing risk for CVD among HIV-infected populations based on guidance extrapolated from general population (HIV-uninfected) cholesterol treatment guidelines across different settings globally. However, HIV-infected patients are consistently under prescribed statin therapy when compared to their HIV-uninfected counterparts. The most commonly studied statins in clinical care and small randomized and cohort studies have been rosuvastatin and atorvastatin. Both agents are preferred for their potent lipid-lowering effects and their favorable or neutral pleotropic effects on chronic inflammation, renal function, and hepatic steatosis among others. However, growing experience with the newer glucuronidated pitavastatin suggests that this agent has virtually no adverse drug interactions with ART or effects on glucose metabolism-all marked additional benefits when compared with rosuvastatin and atorvastatin while maintaining comparable anti-lipid effects. Pitavastatin is therefore the statin of choice for the ongoing largest trial (6500 participants) to test the benefits of statin therapy among HIV-infected adults. Statins are underutilized in the prevention of CVD in HIV-infected populations based on criteria in established cholesterol guidelines. There is a potential role for statin therapy for HIV-infected patients who do not meet guideline criteria which will be further delineated through ongoing clinical trials.

A PRISMA-compliant systematic review and meta-analysis of randomized controlled trials investigating the effects of statin therapy on plasma lipid concentrations in HIV-infected patients

Statin therapy may lower plasma lipid concentrations, but the evidence in HIV-infected patients is still unclear. Therefore, we aimed to investigate the impact of statin therapy on plasma lipid concentrations through a systematic review of the literature and meta-analysis of available randomized controlled trials (RCTs). The literature search included PUBMED, SCOPUS, Web of Science and Google Scholar up to October 30, 2015. The meta-analysis was performed using either a fixed-effects or random-effect model according to I(2) statistic. Effect sizes were expressed as weighted mean difference (WMD) and 95% confidence interval (CI). Two investigators independently reviewed the title or abstract, further reviewed the full-texts and extracted information on study characteristics and study outcomes. Meta-analysis of 12 RCTs with 697 participants suggested significant reductions in plasma concentrations of low density lipoprotein (LDL) cholesterol (WMD: -0.72mmol/L [-27.8mg/dL], 95%CI: -1.04, -0.39, p<0.001; I(2)=85.7%), total cholesterol (WMD: -1.03mmol/L [-39.8mg/dL], 95%CI: -1.42, -0.64, p<0.001; I(2)=94.7%) and non-high density lipoprotein cholesterol (non-HDL-C) (WMD: -0.81mmol/L [-31.3mg/dl], 95%CI: -1.32, -0.30, p=0.002; I(2)=76.5%), and elevations in HDL-C (WMD: 0.072mmol/L [2.8mg/dL], 95%CI: 0.053, 0.092, p<0.001; I(2)=0%) following treatment with statins (mostly of moderate-intensity). No significant alteration in plasma triglycerides (TG) concentrations was found (WMD: -0.16mmol/L [-14.2mg/dL], 95%CI: -0.61, 0.29, p=0.475; I(2)=90.2%). All these effects were robust in sensitivity analysis, suggesting that the computed effect is not driven by any single study. In subgroup analysis, no significant difference was found among different statins in terms of changing plasma concentrations of LDL-C, HDL-C and TG. However, atorvastatin was found to be more efficacious in reducing plasma total cholesterol concentrations (p<0.001). In conclusion, the meta-analysis suggested significant reductions in plasma concentrations of LDL-C, total cholesterol and non-HDL-C, and elevations in HDL-C, but no significant alteration in plasma TG following treatment with statins.