Marked increase in etravirine and saquinavir plasma concentrations during atovaquone/proguanil prophylaxis

The case of a 32-year-old Caucasian female with multi-drug resistant HIV-1 subtype B infection treated with a salvage regimen including maraviroc, raltegravir, etravirine and unboosted saquinavir who started atovaquone/proguanil prophylaxis, is reported. The potential interactions between atovaquone/proguanil and these anti-retroviral drugs are investigated. Pharmacokinetic analyses documented a marked increase in etravirine and saquinavir plasma concentrations (+55% and +274%, respectively), but not in raltegravir and maraviroc plasma concentrations. The evidence that atovaquone/proguanil significantly interacts with etravirine and saquinavir, but not with raltegravir and maraviroc, suggests that the mechanism of interaction is related to cytochrome P450

Plasma concentrations of boosted and unboosted atazanavir are predicted by 63396C>T SNP in the PXR gene

Purpose of the study Atazanavir (ATV) is administered at the usual adult dose of 300 mg with 100 mg of ritonavir (RTV) once a day (boosted). However, 400 mg once a day (unboosted) is also used in some settings. ATV plasma concentrations are influenced by efflux transporters, influx transporters and metabolism enzymes. The expression of many of these proteins is regulated by nuclear receptors such as PXR. Recently polymorphisms in the regulatory region of the PXR gene have been reported to influence its expression and the activity of downstream genes, such as CYP3A4 and ABCB1. The aim of this study was to investigate whether polymorphisms in PXR influence trough concentrations (Ctrough) of boosted or unboosted ATV

A Non-Invasive Method for Detection of Antihypertensive Drugs in Biological Fluids: The Salivary Therapeutic Drug Monitoring

Objectives: Arterial hypertension is still the most frequent cause of cardiovascular and cerebrovascular morbidity and mortality. Antihypertensive treatment has proved effective in reduction of cardiovascular risk. Nevertheless, lifestyle interventions and pharmacological therapy in some cases are ineffective in reaching blood pressure target values, despite full dose and poly-pharmacological treatment. Poor adherence to medications is an important cause of treatment failure. Different methods to assess therapeutic adherence are currently available: Therapeutic drug monitoring in biological fluids has previously demonstrated its efficacy and reliability. Plasma and urine have been already used for this purpose, but they may be affected by some practical limitations. Saliva may represent a feasible alternative. Methods: Fourteen antihypertensive drugs and two metabolites were simultaneously tested in plasma, urine, and saliva. Tested molecules included: atenolol, nebivolol, clonidine, ramipril, olmesartan, telmisartan, valsartan, amlodipine, nifedipine, doxazosin, chlorthalidone, hydrochlorothiazide, indapamide, sacubitril, ramiprilat, and sacubitrilat. Therapeutic drug monitoring was performed using ultra-high performance liquid chromatography, coupled to tandem mass spectrometry (UHPLC-MS/MS). The method has been preliminarily evaluated in a cohort of hypertensive patients. Results: The method has been validated according to US Food and Drug Administration (FDA) and European Medicines Agency (EMA) guidelines. The application on a cohort of 32 hypertensive patients has demonstrated sensibility and specificity of 98% and 98.1%, respectively, with a good feasibility in real-life clinical practice. Conclusion: Saliva may represent a feasible biological sample for therapeutic drug monitoring by non-invasive collection, prompt availability, and potential accessibility also in out-of-clinic settings

Indirect hyperbilirubinemia and jaundice during chronic hepatitis C in an HIV-infected patient treated with glecaprevir/pibrentasvir (GLE/PIB) and antiretroviral therapy (ART). The first reported case in Italy

Glecaprevir (GLE)/pibrentasvir (PIB) is a pangenotypic direct- acting antiviral regimen approved for treating chronic hepatitis C virus. Primary treatment and re-treatment with GLE/PIB are effective and safe for patients without decompensated liver cirrhosis and chronic hepatitis C in a real-world clinical setting. However, in the context of compensated cirrhosis and concomitant adminis- tration of inhibitors of cytochromes, a careful monitoring of liver biomarkers, as well as therapeutic drug monitoring (TDM), may be advisable during GLE/PIB therapy. The GLE / PIB combination is very effective and safe in achieving a sustained virological response, but it can be associated with the development of severe hepatic adverse events, which require virological and serum con- centration monitoring of the two drugs to prevent a serious liver damage. The possible onset of hyperbilirubinemia must not neces- sarily lead to the suspension of therapy, because the phenomenon may be transient. We report what is likely the first known case of severe jaundice after treatment with GLE/PIB in Italy in a patient with compensated chronic hepatitis in the context of HIV disease