Identification of Drugs Acting as Perpetrators in Common Drug Interactions in a Cohort of Geriatric Patients from Southern Italy and Analysis of the Gene Polymorphisms That Affect Their Interacting Potential.

BACKGROUND: Pharmacogenomic factors affect the susceptibility to drug-drug interactions (DDI). We identified drug interaction perpetrators among the drugs prescribed to a cohort of 290 older adults and analysed the prevalence of gene polymorphisms that can increase their interacting potential. We also pinpointed clinical decision support systems (CDSSs) that incorporate pharmacogenomic factors in DDI risk evaluation. METHODS: Perpetrator drugs were identified using the Drug Interactions Flockhart Table, the DRUGBANK website, and the Mayo Clinic Pharmacogenomics Association Table. Allelic variants affecting their activity were identified with the PharmVar, PharmGKB, dbSNP, ensembl and 1000 genome databases. RESULTS: Amiodarone, amlodipine, atorvastatin, digoxin, esomperazole, omeprazole, pantoprazole, simvastatin and rosuvastatin were perpetrator drugs prescribed to >5% of our patients. Few allelic variants affecting their perpetrator activity showed a prevalence >2% in the European population: CYP3A4/5*22, *1G, *3, CYP2C9*2 and *3, CYP2C19*17 and *2, CYP2D6*4, *41, *5, *10 and *9 and SLC1B1*15 and *5. Few commercial CDSS include pharmacogenomic factors in DDI-risk evaluation and none of them was designed for use in older adults. CONCLUSIONS: We provided a list of the allelic variants influencing the activity of drug perpetrators in older adults which should be included in pharmacogenomics-oriented CDSSs to be used in geriatric medicine.

Doravirine Plus Integrase Strand Transfer Inhibitors as a 2-Drug Treatment-Switch Strategy in People Living with HIV: The Real-Life DORINI Multicentric Cohort Study.

BACKGROUND: Few data are available about the efficacy, durability, and tolerability of doravirine (DOR) + integrase strand inhibitors (INI) as a switching strategy among antiretroviral therapy (ART)-experienced people living with HIV (PLWH). SETTING: Retrospective, multicenter cohort study investigating the durability, efficacy, and tolerability of 2 off-label drug associations of DOR + INI among ART-experienced PLWH. METHODS: The study included PLWH who switched to DOR combined with either raltegravir (RAL) or dolutegravir (DTG) between June 1, 2020, and December 31, 2021, with at least 1 follow-up (FU) visit. Virologic, biometric, and metabolic parameters were evaluated at baseline (T0) and at 1-3 (T1), 6 (T2), and 12 (T3) months. Univariate and multivariate survival analyses assessed the 28-week probability of persistence on the regimens. Patient satisfaction was measured using the HIV Treatment Satisfaction Questionnaire. RESULTS: Ninety-five PLWH were included, 52 in DOR + RAL and 43 in DOR + DTG. Six treatment discontinuations were reported during a mean of 37 (±17) weeks of FU (incidence of 2.7 × 1000 person-weeks FU). Only 2 were the result of virological failure without resistance mutations. DOR + DTG demonstrated significantly higher 28-week persistence than DOR + RAL (HR 1.90, 95% CI: 1.24-2.90, log-rank: P = 0.003). Weight, waist circumference, and fasting lipids reduced considerably at T3 vs T0. Overall, high satisfaction with the new treatment was reported, particularly in the DOR + RAL (68 (64-72)/72), compared with the DOR + DTG group (58 (50-65)/72, P < 0.001). CONCLUSIONS: Our experience revealed few treatment discontinuations, improved metabolic parameters, and high patient satisfaction among ART-experienced PLWH switching to DOR combined with INI, irrespective of the specific INI used.

New Avenues for Treatment and Prevention of Drug-Induced Steatosis and Steatohepatitis: Much More Than Antioxidants.

Drug-induced lipid accumulation in the liver may induce two clinically relevant conditions, drug-induced steatosis (DIS) and drug-induced steatohepatitis (DISH). The list of drugs that may cause DIS or DISH is long and heterogeneous and includes therapeutically relevant molecules that cannot be easily replaced by less hepatotoxic medicines, therefore making specific strategies necessary for DIS/DISH prevention or treatment. For years, the only available tools to achieve these goals have been antioxidant drugs and free radical scavengers, which counteract drug-induced mitochondrial dysfunction but, unfortunately, have only limited efficacy. In the present review we illustrate how in vitro preclinical research unraveled new key players in the pathogenesis of specific forms of DISH, and how, in a few cases, proof of concept of the beneficial effects of their pharmacological modulation has been obtained in vivo in animal models of this condition. The key issue emerging from these studies is that, in selected cases, liver toxicity depends on mechanisms unrelated to those responsible for the desired, primary pharmacological effects of the toxic drug and, therefore, specific strategies can be designed to overcome steatogenicity without making the drug ineffective. In particular, the hepatotoxic drug could be given in combination with a second molecule intended to selectively antagonize its liver toxicity whilst, ideally, potentiating its desired pharmacological activity. Although most of the evidence that we discuss is from in vitro or animal models and will need to be further explored and validated in humans, it highlights new avenues to be pursued in order to improve the safety of steatogenic drugs.

Evaluation of the concentrations of psychotropic drugs in HIV-infected versus HIV-negative patients: Potential implications for clinical practice.

Objectives: The management of psychiatric illness in HIV-infected patients is clinically challenging because of the risk of potential drug-drug interactions. Here, we aimed to measure the antidepressant and/or antipsychotic drug concentrations in HIV-infected patients during routine outpatient visits.Methods: Six hundred HIV-infected patients were screened during the first 15 months after the introduction of our outpatient polytherapy management service in a search for subjects treated with psychotropic drugs for at least 3 months. The distribution of psychotropic drug concentrations in HIV-infected patients was compared with that observed in a control group of HIV-negative patients monitored over the same period.Results: The search identified 82 HIV-infected patients concomitantly receiving antiretroviral and psychotropic drug treatment, 55% of whom had plasma psychotropic drug concentrations that were below minimum effective levels. The same result was found in only 26% of the samples taken from HIV-negative patients. These results were not affected by patients' gender, age, adherence to therapies or drug-drug interactions.Conclusions: A higher rate of sub-therapeutic antidepressant and/or antipsychotic drugs concentrations were found in HIV-infected patients. The creation of multidiscliplinary specialist teams may contribute to improving the management of such complex patients.

Darunavir Population Pharmacokinetic Model Based on HIV Outpatient Data.

BACKGROUND: Darunavir is a second-generation protease inhibitor and is registered for the treatment of HIV-1 infection. The aim of this study was to develop and validate a darunavir population pharmacokinetic model based on data from daily practice. METHODS: Data sets were obtained from 2 hospitals: ASST Fatebenefratelli Sacco University Hospital, Italy (hospital A), and University Medical Center Groningen, the Netherlands (hospital B). A pharmacokinetic model was developed using data from the largest data set using the iterative two-stage Bayesian procedure within the MWPharm software package. External validation was conducted using data from the smaller data set with Passing-Bablok regression and Bland-Altman analyses. RESULTS: In total, data from 198 patients from hospital A and 170 patients from hospital B were eligible for inclusion. A 1-compartment model with first-order absorption and elimination resulted in the best model. The Passing-Bablok analysis demonstrated a linear correlation between measured concentration and predicted concentration with r = 0.97 (P < 0.05). The predicted values correlated well with the measured values as determined by a Bland-Altman analysis and were overestimated by a mean value of 0.12 mg/L (range 0.23-0.94 mg/L). A total of 98.2% of the predicted values were within the limits of agreement. CONCLUSIONS: A robust population pharmacokinetic model was developed, which can support therapeutic drug monitoring of darunavir in daily outpatient settings.

Uptake of hepatitis C virus treatment in HIV/hepatitis C virus-coinfected patients across Europe in the era of direct-acting antivirals.

BACKGROUND AND AIMS: To investigate the uptake of hepatitis C virus (HCV) therapy among HIV/HCV-coinfected patients in the pan-European EuroSIDA study between 2011 and 2016. METHODS: All HCV-RNA+ patients were included. Baseline was defined as latest of anti-HCV+, January 2011 or enrolment in EuroSIDA. The incidence of starting first interferon-free direct-acting antiviral (DAA) therapy was calculated. Factors associated with starting interferon-free DAA were determined by Poisson regression. RESULTS: Among 4308 HCV-RNA+ patients (1255, 970, 663, 633, 787 from South, West, North, Central East and East Europe, respectively) with 11 863 person-years of follow-up, 1113 (25.8%) started any HCV therapy. Among patients with at least F3 fibrosis, more than 50% in all regions remained untreated. The incidence (per 1000 person-years of follow-up, 95% confidence interval) of starting DAA increased from 7.8 (5.9-9.8) in 2014 to 135.2 (122.0-148.5) in 2015 and 128.9 (113.5-144.3) in 2016. The increase was highest in North and West and intermediate in South, but remained modest in Central East and Eastern Europe. After adjustment, women, individuals from Central East or East, genotype 3, antiretroviral therapy naïve and those with detectable HIV-RNA were less likely to start DAA. Older persons, those with HCV-RNA more than 500 000 IU/ml and those with more advanced liver fibrosis were more likely to start DAA. CONCLUSION: Uptake of DAA therapy among HIV/HCV-coinfected patients increased considerably in Western Europe between 2014 and 2016, but was modest in Central East and East. In all regions more than 50% with at least F3 fibrosis remained untreated. Women were less likely to start DAA.

Correlation between inner retinal layer thickness and cognitive function in HIV: new insights from an exploratory study.

OBJECTIVE: To compare retinal layer thickness in HIV-infected subjects with (CI-HIV) and without (NCI-HIV) cognitive impairment, with a control population and to correlate this with the cognitive status of the patient and other clinical parameters. DESIGN: Single-center cross-sectional study. METHODS: Participants with controlled HIV infection aged between 40 and 70 years and sex-matched and age-matched controls were enrolled. Retinal nerve fiber layer (RNFL), ganglion cell layer (GCL) and inner plexiform layer (IPL) thickness were assessed using optical coherence tomography. These measurements in HIV patients were compared with those in controls. Age-related and sex-related changes were compared in both groups. Other variables studied in HIV patients included: duration of HIV infection, CD4 cell count nadir, antiretroviral therapy regimen and cognitive status using the Montreal Cognitive Assessment (MoCA) test. RESULTS: Sixty-nine individuals, 34 with and 35 without cognitive impairment, and 70 controls were enrolled. GCL was significantly thinner in CI-HIV patients compared with NCI-HIV patients and controls (P = 0.01 and P = 0.02, respectively). GCL and IPL thickness significantly decreased with age in patients with HIV (P = 0.0003, P = 0.02, respectively, for the entire cohort). This change was not seen in controls. MoCA test score significantly decreased with age in HIV patients and controls. GCL thickness positively correlated with cognitive function across the entire HIV cohort (P = 0.02). CONCLUSION: GCL was thinner in HIV patients with cognitive impairment. GCL thickness correlated positively with cognitive function and negatively with age in HIV patients. GCL thickness may reflect accelerated cognitive aging in HIV.

Effect of Cobicistat on Tenofovir Disoproxil Fumarate (TDF): What Is True for TAF May Also Be True for TDF.

BACKGROUND: The dose of tenofovir alafenamide is reduced from 25 to 10 mg daily when given with boosting agents. However, such dose reduction has never been adopted for tenofovir disoproxil fumarate (TDF). In this study, we aim to quantify the effect of cobicistat (COBI) both on tenofovir concentrations and TDF durability in real life setting. METHODS: HIV-positive patients receiving TDF-containing antiretroviral therapies with at least 1 assessment of tenofovir plasma trough concentrations were included in the study. Univariate and multivariate regression analyses were performed considering tenofovir concentration as the dependent variable and clinical characteristics as independent covariates. Subsequently, survival and Cox analyses were performed considering as the primary outcome TDF discontinuation for any reasons. RESULTS: Patients were given TDF with protease inhibitors/ritonavir (n = 212), non-nucleoside reverse transcriptase inhibitors (n = 176), integrase inhibitors (dolutegravir or raltegravir, n = 46), or with elvitegravir/COBI (ELV/COBI) (n = 76). By multivariate analysis, concomitant antiretroviral therapies resulted significantly associated with tenofovir levels, with the highest drug concentrations measured in patients given ELV/COBI. By survival analysis, we found that patients given TDF with ELV/COBI had the lowest rate of drug durability. Overall, these patients had a 2.3-fold increased risk to experience TDF discontinuation. CONCLUSIONS: Coadministration with COBI resulted in significantly higher tenofovir concentrations and higher TDF discontinuation compared with other antiretroviral regimens. Accordingly, the possibility that the lack of proper dose adjustment for TDF when given with COBI might have biased the safety comparisons with tenofovir alafenamide during registrative trials cannot be ruled out.

Generics for the Treatment of Hepatitis C in Monoinfected and HIV-coinfected Patients: Pros and Cons.

The treatment of hepatitis C virus in monoinfected and HIV-coinfected patients has greatly changed over recent years as a result of the introduction of direct-acting antiviral agents (DAAs), which have revolutionized clinical outcomes and led to sustained virological response rates above 90-95%. The discovery of new molecules and the subsequent competition between pharmaceutical companies, together with the negotiated price policies pursued by many national health systems, have led to a gradual reduction in the cost of DAAs, and expand their use to an increasing number of patients, including those with mild liver damage. However, the cost of branded DAAs is still too high for many developing countries, and many patients are still left without therapy. In this context, the availability of generic DAAs certainly provides a major opportunity for further cost savings in industrialized countries and will ensure broader access to treatment elsewhere. However, their more widespread use must not lead to a reduction in pharmaceutical quality because this could result in serious clinical consequences, including high rat failures, and selection of drug resistance. It is therefore essential that all generic formulations of DAAs are pre-qualified by the World Health Organization, and that real-life studies are carried out to verify their pharmacokinetic bioequivalence (ideally in patients, and not just in healthy volunteers) and clinical effectiveness. In this regard, lessons from expanding access programs in the HIV field would be very helpful.

Effect of Legal Status on the Early Treatment Outcomes of Migrants Beginning Combined Antiretroviral Therapy at an Outpatient Clinic in Milan, Italy.

OBJECTIVE: In a setting of free access to HIV care, we compared the early treatment outcomes of HIV-infected undocumented migrants (UMs), documented migrants (DMs), and Italian subjects. METHODS: The clinical data of 640 Italians and 245 migrants who started combined antiretroviral therapy (cART) at an HIV clinic in Milan, Italy, were reviewed. The migrants were mainly Latin Americans (83 DMs and 56 UMs) or sub-Saharan Africans (52 DMs and 11 UMs), but a minority were of other origin (33 DMs and 10 UMs). Retention in follow-up and HIV suppression were compared between UMs, DMs, and natives 12 months ± 90 days after start of cART. RESULTS: There were no significant between-group differences in the stage of HIV infection at the start of cART or the type of regimen received. The Latin American DMs and UMs included a higher proportion of transgender women than the other ethnic groups (P < 0.001). The UMs were less frequently followed up after 12 months than the DMs and natives (P = 0.004) and were more frequently permanently lost to follow-up (P < 0.001). UM status was an independent predictor of lost to follow-up (adjusted odds ratio 8.05, P < 0.001). The DMs and UMs were less frequently HIV suppressed after 12 months than the natives (78% and 80.7% vs 90.5%, P = 0.001), and Latin American migrants were significantly less likely to be virologically suppressed than the natives (adjusted odds ratio 0.30, P = 0.001). CONCLUSIONS: Despite their free access to cART, subgroups of migrants facing multiple levels of vulnerability still have difficulties in gaining optimal HIV care.

Elvitegravir/cobicistat-associated toxic optical neuropathy in an HIV-infected patient: a call for caution?

Ocular toxicity may not only be caused by medication overdoses and drug-drug interactions, but also by chronic administration of medications at recommended doses. We describe a case of an HIV-infected patient who experienced significant and sustained bilateral visual loss 2 months after starting treatment with elvitegravir/cobicistat/tenofovir/emtricitabine. Given the absence of any evidence of tenofovir- or emtricitabine-induced optical neuropathy after several years of clinical use, the antiretroviral therapy was promptly changed to tenofovir/emtricitabine plus atazanavir/ritonavir, which led to a progressive improvement in visual acuity. However, visual evoked potentials never returned to normal amplitudes. This is the first report of toxic optical neuropathy associated with the use of elvitegravir/cobicistat. It is imperative to recognize any signs of possible eye toxicity as rapidly as possible, and refer affected patients to an ophthalmologist promptly because early detection and the withdrawal of the offending agent are crucial in reversing this adverse ocular event.

Abacavir-induced liver toxicity

Abstract Abacavir-induced liver toxicity is a rare event almost exclusively occurring in HLA B*5701-positive patients. Herein, we report one case of abnormal liver function tests occurring in a young HLA B*5701-negative woman on a stable nevirapine-based regimen with no history of liver problems or alcohol abuse after switching to abacavir from tenofovir. We also investigated the reasons for abacavir discontinuation in a cohort of patients treated with abacavir-lamivudine-nevirapine.

Abacavir-induced liver toxicity.

Abacavir-induced liver toxicity is a rare event almost exclusively occurring in HLA B*5701-positive patients. Herein, we report one case of abnormal liver function tests occurring in a young HLA B*5701-negative woman on a stable nevirapine-based regimen with no history of liver problems or alcohol abuse after switching to abacavir from tenofovir. We also investigated the reasons for abacavir discontinuation in a cohort of patients treated with abacavir-lamivudine-nevirapine.