Inflammation and pharmacokinetics: potential implications for HIV-infection

Trajectories of Antiretroviral Therapy Adherence and Virologic Failure in Women With HIV in the United States

BACKGROUND

Women with HIV (WHIV) in the United States face many challenges with adherence to antiretroviral therapy (ART), and suboptimal adherence often leads to virologic failure. This study aimed to determine the association between ART adherence trajectories and the risk of virologic failure.

METHODS

We included WHIV (aged 18 years or older) enrolled in the Women's Interagency HIV Study in the United States from April 2014 to September 2019 who had at least 2 consecutive measurements of HIV RNA and ≥3 measurements of self-reported adherence. Group-based trajectory modeling was used to identify adherence trajectories. Cox proportional hazard ratios were used to measure the association.

MAIN OUTCOME MEASURE

Virologic failure was defined as HIV RNA ≥200 copies/mL at 2 consecutive visits.

RESULTS

We included 1437 WHIV (median age 49 years). Of all women, 173 (12.0%) experienced virologic failure. Four adherence trajectories were identified, namely "consistently high" (26.3%), "moderate increasing" (9.5%), "moderate decreasing" (30.6%), and "consistently low" (33.5%). Women in the consistently low adherence group consumed alcohol and experienced depression more than other groups. Compared with the "consistently high" trajectory, the risk of virologic failure was higher among women with "consistently low" [adjusted hazard ratio (aHR) 2.8; 95% confidence interval (CI): 1.6 to 4.9; P < 0.001] and "moderate decreasing" adherence trajectories (aHR 1.8; 95% CI: 1.0 to 3.2; P = 0.04), but it was similar to those with "moderate increasing" adherence trajectory (aHR 1.0; 95% CI: 0.4 to 2.5; P = 0.94).

CONCLUSIONS

Adherence to ART remains a challenge among WHIV. Multilevel behavioral interventions to address poor adherence, alcohol consumption, and depression are needed.

Lamivudine and Emtricitabine Dosing Proposal for Children with HIV and Chronic Kidney Disease, Supported by Physiologically Based Pharmacokinetic Modelling

Dose recommendations for lamivudine or emtricitabine in children with HIV and chronic kidney disease (CKD) are absent or not supported by clinical data. Physiologically based pharmacokinetic (PBPK) models have the potential to facilitate dose selection for these drugs in this population. Existing lamivudine and emtricitabine compound models in Simcyp^® (v21) were verified in adult populations with and without CKD and in non-CKD paediatric populations. We developed paediatric CKD population models reflecting subjects with a reduced glomerular filtration and tubular secretion, based on extrapolation from adult CKD population models. These models were verified using ganciclovir as a surrogate compound. Then, lamivudine and emtricitabine dosing strategies were simulated in virtual paediatric CKD populations. The compound and paediatric CKD population models were verified successfully (prediction error within 0.5- to 2-fold). The mean AUC ratios in children (GFR-adjusted dose in CKD population/standard dose in population with normal kidney function) were 1.15 and 1.23 for lamivudine, and 1.20 and 1.30 for emtricitabine, with grade-3- and -4-stage CKD, respectively. With the developed paediatric CKD population PBPK models, GFR-adjusted lamivudine and emtricitabine dosages in children with CKD resulted in adequate drug exposure, supporting paediatric GFR-adjusted dosing. Clinical studies are needed to confirm these findings.

P-Glycoprotein and Organic Anion Transporter Polypeptide 1B/Breast Cancer Resistance Protein Drug Transporter Activity in Pregnant Women Living With HIV

This study evaluates the influence of pregnancy and HIV infection in conjunction with the use of raltegravir, lamivudine, and tenofovir disoproxil fumarate (combined antiretroviral therapy [cART]) on intestinal P-glycoprotein (P-gp) and hepatic organic anion transporter polypeptide (OATP) 1B1/1B3 and/or breast cancer resistance protein (BCRP) drug transporter activity using rosuvastatin (OATP1B/BCRP) and fexofenadine (P-gp) probes. Single oral doses of 5-mg rosuvastatin and 60-mg fexofenadine were administered to women living with HIV under cART in the third trimester of gestation (n = 15) and postpartum period (n = 10). A control group of 12 healthy nonpregnant women also was investigated. Pharmacokinetic parameters were estimated by using a noncompartmental method and evaluated by t test (P < .05). The rosuvastatin area under the plasma concentration-time curve from time 0 to the last quantifiable concentration (AUC_0-last ) value was higher in the third trimester of pregnancy (19.5 [95%CI, 16.8-22.3] ng • h/mL] when compared to postpartum (13.3 [95%CI, 9.3-17.5] ng • h/mL), while the fexofenadine AUC_0-last values did not differ between the third trimester of pregnancy (738.0 [95%CI, 611.4-864.6] ng • h/mL) and postpartum period (874.9 [95%CI, 408.2-1342.0] ng• h/mL). The rosuvastatin AUC_0-last values did not differ between healthy nonpregnant women (13.8 [95%CI, 10.0-17.6] ng • h/mL) and women living with HIV in the postpartum period (13.3 [95%CI, 9.3-17.5] ng • h/mL), and the fexofenadine AUC_0-last values did not differ between the 2 investigated groups (603.6 [95%CI, 467.5-739.7] ng • h/mL vs 874.9 [95%CI, 408.2-1342.0] ng • h/mL). It is suggested that gestation inhibits the hepatic OATP1B1/1B3 and/or BCRP activity but does not alter intestinal P-gp activity. The influence of HIV infection in conjunction with use of cART on OATP1B/BCRP and intestinal P-gp activity was not observed.

The Effect of Rosuvastatin on Plasma/Serum Levels of High-Sensitivity C-Reactive Protein, Interleukin-6, and D-Dimer in People Living with Human Immunodeficiency Virus: A Systematic Review and Meta-Analysis

Rosuvastatin therapy might have an effect on the inflammatory and coagulation biomarkers. However, the evidence about the effect of rosuvastatin therapy on the high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), and D-dimer levels among people living with human immunodeficiency virus (PLHIV) is still unclear. Therefore, this study investigated the relational effect of rosuvastatin therapy on serum/plasma hsCRP, IL-6 and D-dimer levels in PLHIV. The literature search was done from Embase, PubMed, and Web of Science databases. The review and meta-analysis included studies written in English language up to January 4, 2020. Random effects model was used to evaluate the pooled standard mean difference with 95% confidence interval. A meta-analysis was performed using nine articles with 392 PLHIV. The result revealed that the plasma/serum levels of IL-6 were significantly reduced after the intervention. However, hsCRP and D-dimer levels showed no significant difference (p > .05) between before and after the intervention. The subgroup analysis showed that there was significant association between PLHIV ages <45 years and cohort studies with IL-6 levels. The current CD4⁺ counts ≥350 cells/mm³ correlated with hsCRP as well as IL-6. Similarly, nadir CD4⁺ counts ≥200 cells/mm³ and duration of HIV diagnosis <10 years also showed significant association with IL-6 and D-dimer levels. It was also indicated that participants who were under antiretroviral drug for <7 years were significantly associated with hsCRP levels. This study established that IL-6 levels were significantly reduced after the intervention while hsCRP and D-dimer levels showed no significant difference between before and after the intervention.

No implication of HIV coinfection on the plasma exposure to rifampicin, pyrazinamide, and ethambutol in tuberculosis patients

There are contrasting findings regarding the effect of HIV on the pharmacokinetics of first‐line anti‐tubercular drugs (FLATDs) due to a lack of prospective controlled clinical studies, including patients with tuberculosis (TB) and patients with TB living with HIV. This study aims to assess the effect of HIV coinfection and antiviral therapy on the plasma exposure to FLATDs in patients with TB. HIV negative (TB‐HIV− group; n = 15) and HIV positive (TB‐HIV+ group; n = 18) adult patients with TB were enrolled during the second month of FLATDs treatment. All TB‐HIV+ patients were on treatment with lamivudine, tenofovir (or zidovudine), and raltegravir (or efavirenz). Serial blood sampling was collected over 24 h and FLATDs pharmacokinetic parameters were evaluated using noncompartmental methods. In the TB‐HIV+ patients, dose‐normalized plasma exposure area under the curve from zero to 24 h (nAUC_0–24; geometric mean and 95% confidence interval [CI]) values at steady‐state to rifampicin, pyrazinamide, and ethambutol were 18.38 (95% CI 13.74–24.59), 238.21 (95% CI 191.09–296.95), and 18.33 (95% CI 14.56–23.09) µg∙h/ml, respectively. Similar plasma exposure was found in the TB‐HIV− patients. The geometric mean and 90% CI of the ratios between TB‐HIV− and TB‐HIV+ groups suggest no significant pharmacokinetic interaction between the selected antivirals and FLATDs. Likewise, HIV coinfection itself does not appear to have any effect on the plasma exposure to FLATDs.

IL-6 downregulates hepatic carboxylesterases via NF-κB activation in dextran sulfate sodium-induced colitis

Ulcerative colitis (UC) is associated with increased levels of inflammatory factors, which is attributed to the abnormal expression and activity of enzymes and transporters in the liver, affecting drug disposition in vivo. This study aimed to examine the impact of intestinal inflammation on the expression of hepatic carboxylesterases (CESs) in a mouse model of dextran sulfate sodium (DSS)-induced colitis. Two major CESs isoforms, CES1 and CES2, were down-regulated, accompanied by decreases in hepatic microsomal metabolism of clopidogrel and irinotecan. Meanwhile, IL-6 levels significantly increased compared with other inflammatory factors in the livers of UC mice. In contrast, using IL-6 antibody simultaneously reversed the down-regulation of CES1, CES2, pregnane X receptor (PXR), and constitutive androstane receptor (CAR), as well as the nuclear translocation of NF-κB in the liver. We further confirmed that treatment with NF-κB inhibitor abolished IL-6-induced down-regulation of CES1, CES2, PXR, and CAR in vitro. Thus, it was concluded that IL-6 represses hepatic CESs via the NF-κB pathway in DSS-induced colitis. These findings indicate that caution should be exercised concerning the proper and safe use of therapeutic drugs in patients with UC.

Inflammation Induces Changes in the Functional Expression of P-gp, BCRP, and MRP2: An Overview of Different Models and Consequences for Drug Disposition

The ATP-binding cassette (ABC) transporters play a key role in drug pharmacokinetics. These membrane transporters expressed within physiological barriers can be a source of pharmacokinetic variability. Changes in ABC transporter expression and functionality may consequently affect the disposition of substrate drugs, resulting in different drug exposure. Inflammation, present in several acute and chronic diseases, has been identified as a source of modulation in drug transporter expression leading to variability in drug response. Its regulation may be particularly dangerous for drugs with a narrow therapeutic index. In this context, numerous in vitro and in vivo models have shown up- or downregulation in the expression and functionality of ABC transporters under inflammatory conditions. Nevertheless, the existence of contradictory data and the lack of standardization for the models used have led to a less conclusive interpretation of these data.

Semimechanistic Modeling of the Effects of Blast Overpressure Exposure on Cefazolin Pharmacokinetics in Mice

Cefazolin is a first-line antibiotic to treat infection related to deployment-associated blast injuries. Prior literature demonstrated a 331% increase cefazolin liver area under the curve (AUC) in mice exposed to a survivable blast compared with controls. We repeated the experiment, validated the findings, and established a semimechanistic two-compartment pharmacokinetic (PK) model with effect compartments representing the liver and skin. We found that blast statistically significantly increased the pseudo-partition coefficient to the liver by 326% (95% confidence interval: 76-737%), which corresponds to the observed 331% increase in cefazolin liver AUC described previously. To a lesser extent, plasma AUC in blasted mice increased 14-45% compared with controls. Nevertheless, the effects of blast on cefazolin PK were transient, normalizing by 10 hours after the dose. It is unclear as to how this blast effect t emporally translates to humans; however, given the short-lived effect on PK, there is insufficient evidence to recommend cefazolin dosing changes based on blast overpressure injury alone. Clinicians should be aware that cefazolin may cause drug-induced liver injury with a single dose and the risk may be higher in patients with blast overpressure injury based on our findings. SIGNIFICANCE STATEMENT: Blast exposure significantly, but transiently, alters cefazolin pharmacokinetics in mice. The questions of whether other medications or potential long-term consequences in humans need further exploration.

Drug-drug Interactions between COVID-19 Treatments and Antidepressants, Mood Stabilizers/Anticonvulsants, and Benzodiazepines: Integrated Evidence from 3 Databases

INTRODUCTION

The SARS-CoV-2 pandemic with psychiatric comorbidities leads to a scenario in which the use of psychotropic drugs may be required. This requires the support of evidence-based medicine to take into account possible interactions between antidepressants, mood stabilizers, benzodiazepines, and coronavirus infection treatments.

METHODS

Three databases were consulted: (a) Lexicomp Drug Interactions, (b) Micromedex Solutions Drugs Interactions, (c)Liverpool Drug Interaction Group for COVID-19 therapies. The CredibleMeds QTDrugs List was also queried. Hydroxychloroquine, chloroquine, azithromycin, lopinavir-ritonavir, remdesivir, favipiravir, tocilizumab, baricitinib, anakinra, and dexamethasone - drugs used for SARS-CoV-2 - were analyzed, and consensus recommendations are made.

RESULTS

The potential interactions of agomelatine, desvenlafaxine, duloxetine, milnacipran, and vortioxetine with COVID-19 treatments shall be considered less risky. Antidepressant interactions with hydroxychloroquine, chloroquine, and azithromycin enhance the risk of QT prolongation, and ECG monitoring is advised for most antidepressants. Antidepressants with lopinavir/ritonavir involve multiple CYP enzyme interactions (except with milnacipran). Gabapentin, oxcarbazepine, pregabalin, topiramate, and zonisamide are safe treatment options that have no significant interactions with COVID-19 treatments. Lithium is contraindicated with hydroxychloroquine, chloroquine, and azithromycin. Precaution should be taken in using valproic acid with lopinavir-ritonavir. The use of benzodiazepines does not present a risk of drug interaction with COVID-19 treatments, except lopinavir/ritonavir.

CONCLUSIONS

Clinicians prescribing antidepressants, mood stabilizers/anticonvulsants, and benzodiazepines, should be aware of the probable risk of drug-drug interaction with COVID-19 medications and may benefit from heeding these recommendations for use to ensure patient safety.

Potential Effects of COVID-19 on Cytochrome P450-Mediated Drug Metabolism and Disposition in Infected Patients

Coronavirus Disease 2019 (COVID-19) has been a global health crisis since it was first identified in December 2019. In addition to fever, cough, headache, and shortness of breath, an intense increase in immune response-based inflammation has been the hallmark of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2) virus infection. This narrative review summarizes and critiques pathophysiology of COVID-19 and its plausible effects on drug metabolism and disposition. The release of inflammatory cytokines (e.g., interleukins, tumor necrosis factor α), also known as 'cytokine storm', leads to altered molecular pathophysiology and eventually organ damage in the lung, heart, and liver. The laboratory values for various liver function tests (e.g., alanine aminotransferase, aspartate aminotransferase, total bilirubin, albumin) have indicated potential hepatocellular injury in COVID-19 patients. Since the liver is the powerhouse of protein synthesis and the primary site of cytochrome P450 (CYP)-mediated drug metabolism, even a minor change in the liver function status has the potential to affect the hepatic clearance of xenobiotics. It has now been well established that extreme increases in cytokine levels are common in COVID-19 patients, and previous studies with patients infected with non-SARS-CoV-2 virus have shown that CYP enzymes can be suppressed by an infection-related cytokine increase and inflammation. Alongside the investigational COVID-19 drugs, the patients may also be on therapeutics for comorbidities; especially epidemiological studies have indicated that individuals with hypertension, hyperglycemia, and obesity are more vulnerable to COVID-19 than the average population. This complicates the drug-disease interaction profile of the patients as both the investigational drugs (e.g., remdesivir, dexamethasone) and the agents for comorbidities can be affected by compromised CYP-mediated hepatic metabolism. Overall, it is imperative that healthcare professionals pay attention to the COVID-19 and CYP-driven drug metabolism interactions with the goal to adjust the dose or discontinue the affected drugs as appropriate.

Lower Cumulative Antiretroviral Exposure in People Living With HIV and Diabetes Mellitus

OBJECTIVE

People living with HIV (PLWH) are living longer and developing more non-AIDS comorbidities, which negatively impact antiretroviral therapy (ART) adherence. Tenofovir diphosphate (TFV-DP) in dried blood spots (DBS) is a novel pharmacologic measure of cumulative ART adherence that is predictive of viral suppression and future viremia. However, the relationship between non-AIDS comorbidities and this adherence measure is unknown. We aimed to evaluate the association between 3 non-AIDS comorbidities (diabetes mellitus (DM), hypertension, and hyperlipidemia) and TFV-DP in DBS in PLWH.

METHODS

Blood for TFV-DP in DBS and HIV viral load was prospectively collected from PLWH on tenofovir disoproxil fumarate for up to 3 times over 48 weeks. Non-AIDS comorbidities were recorded. Mixed effect multivariable linear regression models were used to estimate the changes in TFV-DP concentrations in DBS according to the presence of comorbidities and to estimate the percent differences in TFV-DP concentrations between these groups.

RESULTS

A total of 1144 person-visits derived from 523 participants with available concentrations of TFV-DP in DBS were included in this analysis. In univariate analysis, no significant association between non-AIDS comorbidities (categorized as having 0, 1, 2, or 3 comorbidities) and the concentrations of TFV-DP in DBS was observed (P = 0.40). Participants who had DM had 25% lower (95% confidence interval: -36% to -12%; P < 0.001) TFV-DP in DBS than participants without DM after adjusting for age, gender, race, body mass index, estimated glomerular filtration rate, CD4 T-cell count, hematocrit, ART class, patient-level medication regimen complexity index, and 3-month self-reported adherence.

CONCLUSIONS

Diabetic PLWH have lower concentrations of TFV-DP in DBS compared with those without DM. Further research is required to identify the clinical implications and biological mechanisms underlying these findings.

Concerns about pharmacokinetic (PK) and pharmacokinetic-pharmacodynamic (PK-PD) studies in the new therapeutic area of COVID-19 infection

In the context of the COVID-19 pandemic, several drugs have been repurposed as potential candidates for the treatment of COVID-19 infection. While preliminary choices were essentially based on in vitro potency, clinical translation into effective therapies may be challenging due to unfavorable in vivo pharmacokinetic properties at the doses chosen for this new indication of COVID-19 infection. However, available pharmacokinetic and pharmacokinetic-pharmacodynamic studies suffer from severe limitations leading to unreliable conclusions, especially in term of dosing optimization. In this paper we propose to highlight these limitations and to identify some of the major requirements that need to be addressed in designing PK and PK-PD studies in this era of COVID. A special attention should be paid to pre-analytical and analytical requirements and to the proper collection of covariates affecting dose-exposure relationships (co-medications, use of specific organ support techniques and other clinical and para-clinical data). We also promote the development of population PK and PK-PD models specifically dedicated to COVID-19 patients since those previously developed for other diseases (SEL, malaria, HIV) and clinical situations (steady-state, non-ICU patients) are not representative of severe patients. Therefore, implementation of well-designed PK and PD studies targeted to COVID-19 patients is urgently needed. For that purpose we call for multi-institutional collaborative work and involvement of clinical pharmacologists in multidisciplinary research consortia.

Effects of Exercise Training and Statin Use in People Living with Human Immunodeficiency Virus with Dyslipidemia

PURPOSE

To evaluate the effects of the combination of exercise training (ET) and statins in people living with human immunodeficiency virus.

METHODS

This was a randomized, double-blind, placebo-controlled clinical trial. Eighty-three people living with human immunodeficiency virus were assigned to either placebo (PL), statins (STA), PL + ET (PLET) or STA + ET (STAET) groups. Volunteers assigned to STA and STAET groups were administered 10 mg of rosuvastatin, whereas the PL and PLET groups were administered a placebo. The PLET and STAET groups performed ET three times a week. Before and after the 12-wk follow-up, the volunteers underwent to anthropometric assessment and blood collection to evaluate lipid profile, cardiovascular markers, inflammatory profile; a Doppler ultrasound examination, muscle strength (MS) and cardiorespiratory fitness (CF) tests were performed.

RESULTS

There was a decrease in total cholesterol, triglycerides, low-density lipoprotein, C-reactive protein, fibrinogen, interleukin (IL)-1β and right carotid intima-media thickness in the STA, PLET, and STAET groups compared with PL group (P < 0.001). Furthermore, there was a decrease in total cholesterol, triglycerides, low-density lipoprotein, IL-1β, IL-6, and IL-8 levels and in left and right carotid intima-media thickness and an increase in HDL-c levels in the STAET groups compared with the STA (P ≤ 0.001) and PLET groups (P ≤ 0.001). There was an increase in IL-10 levels, peak-systolic velocity, end-diastolic velocity, wall shear rate in the PLET and STAET groups compared with the PL (P ≤ 0.001) and STA groups (P ≤ 0.001). The PLET and STAET groups reduced body fat mass, body fat percentage and increased lean body mass, MS and CF compared with PL (P ≤ 0.001) and STA (P ≤ 0.001) groups.

CONCLUSIONS

The combination of ET and statins is useful to enhance lipid and inflammatory profiles, reduce cardiovascular disease markers, and improve Doppler ultrasound findings, MS and CF in people living with HIV.

Inflammation is a major regulator of drug metabolizing enzymes and transporters: Consequences for the personalization of drug treatment

Inflammation is an evolutionary process that allows survival against acute infection or injury. Inflammation is also a pathophysiological condition shared by numerous chronic diseases. In addition, inflammation modulates important drug-metabolizing enzymes and transporters (DMETs), thus contributing to intra- and interindividual variability of drug exposure. A better knowledge of the impact of inflammation on drug metabolism and its related clinical consequences would help to personalize drug treatment. Here, we summarize the kinetics of inflammatory mediators and the underlying transcriptional and post-transcriptional mechanisms by which they contribute to the inhibition of important DMETs. We also present an updated overview of the effect of inflammation on the pharmacokinetic parameters of most of the drugs that are DMET substrates, for which therapeutic drug monitoring is recommended. Furthermore, we provide opinions on how to integrate the inflammatory status into pharmacogenetics, therapeutic drug monitoring, and population pharmacokinetic strategies to improve the personalization of drug treatment for each patient.

Systemic Lupus Erythematosus Activity Affects the Sinusoidal Uptake Transporter OATP1B1 Evaluated by the Pharmacokinetics of Atorvastatin

The present study assessed the effect of systemic lupus erythematosus (SLE) activity, a chronic and inflammatory autoimmune disease, on the sinusoidal uptake transporter OATP1B1 using atorvastatin (ATV) as a probe drug. Fifteen healthy subjects, 13 patients with controlled SLE (SLEDAI 0-4), and 12 patients with uncontrolled SLE (SLEDAI from 6 to 15), all women, were investigated. Apparent total clearance of midazolam (MDZ), a marker of CYP3A4 activity, did not vary among the three investigated groups. The controlled and uncontrolled SLE groups showed higher plasma concentrations of MCP-1 and TNF-α, while the uncontrolled SLE group also showed higher plasma concentrations of IL-10. The uncontrolled SLE group showed higher area under the curve (AUC) for ATV (60.47 (43.76-83.56) vs. 30.56 (22.69-41.15) ng⋅hour/mL) and its inactive metabolite ATV-lactone (98.74 (74.31-131.20) vs. 49.21 (34.89-69.42) ng⋅hour/mL), and lower apparent total clearance (330.7 (239.30-457.00) vs. 654.5 (486.00-881.4) L/hour) and apparent volume of distribution (2,609 (1,607-4,234) vs. 7,159 (4,904-10,450) L), when compared to the healthy subjects group (geometric mean and 95% confidence interval). The pharmacokinetics of ATV and its metabolites did not differ between the healthy subject group and the patients with controlled SLE group. In conclusion, uncontrolled SLE increased the systemic exposure to both ATV and ATV-lactone, inferring inhibition of OATP1B1 activity, once in vivo CYP3A4 activity assessed by oral clearance of MDZ was unaltered. The inflammatory state, not the disease itself, was responsible for the changes described in the uncontrolled SLE group as a consequence of inhibition of OATP1B1, because systemic exposure to ATV and its metabolites were not altered in patients with controlled SLE.

Differential effects of C-reactive protein levels on voriconazole metabolism at three age groups in allogeneic hematopoietic cell transplant recipients

The aim of this study was to evaluate the impact of inflammation on voriconazole (VRCZ) metabolism at three age groups in the allogeneic hematopoietic cell transplant recipients of the Chinese population. The study was performed with collecting more than one VRCZ trough concentration and C-reactive protein (CRP) levels. Longitudinal analysis, correlation and comparative analysis were conducted to evaluate. A total of 104 patients with 386 VRCZ trough concentration and CRP level measured on the same day were collected. For children, CRP levels significantly associated with VRCZ pharmacokinetics in age 11-18 years but not in age 2-10 years. For adults, VRCZ concentrations were increased slightly by 0.006 mg/L when every 1 mg/L increased in CRP levels. Additionally, meropenem and inflammation might work together to cause a higher VRCZ concentration. Therefore, therapeutic drug monitoring of VRCZ should be warranted at age >10 years in allogeneic hematopoietic cell transplant recipients with elevated CRP level.

Tenofovir Diphosphate in Dried Blood Spots Is Strongly Associated With Viral Suppression in Individuals With Human Immunodeficiency Virus Infections

BACKGROUND

Although tenofovir diphosphate (TFV-DP) in dried blood spots (DBS) is a predictor of adherence and pre-exposure prophylaxis efficacy, its utility in human immunodeficiency virus (HIV) treatment remains unknown.

METHODS

DBS for TFV-DP were collected up to 3 times over 48 weeks in persons living with HIV (PLWH) who were receiving TFV disoproxil fumarate (TDF)-based therapy. Log-transformed baseline TFV-DP was compared using t-tests or analyses of variance; generalized estimating equations were used to estimate the adjusted odds ratio (aOR) of viral suppression (<20 copies/mL) based on the TFV-DP concentration at the study visit.

RESULTS

We analyzed 1199 DBS from 532 participants (76 female; 101 Black, 101 Hispanic). Among the virologically-suppressed participants at baseline (n = 347), TFV-DP was lower in Blacks (geometric mean 1453, 95% confidence interval [CI] 1291-1635) vs Whites (1793, 95% CI 1678-1916; P = .002) and Hispanics (1760, 95% CI 1563-1982; P = .025); in non-boosted (1610, 95% CI 1505-1723) vs. boosted (1888, 95% CI 1749-2037; P = .002) regimens; and in non-nucleoside reverse transcription inhibitor-based (1563, 95% CI 1432-1707) vs. boosted protease inhibitor-based (1890, 95% CI 1704-2095; P = .006) and multiclass-based (1927, 95% CI 1650-2252; P = .022) regimens. The aOR of virologic suppression, after adjusting for age, gender, race, body mass index, estimated glomerular filtration rate, CD4+ T-cell count, antiretroviral drug class and duration of therapy, was 73.5 (95% CI 25.7-210.5; P < .0001) for a TFV-DP concentration ≥1850 fmol/punch compared to <350 fmol/punch.

CONCLUSIONS

TFV-DP in DBS is strongly associated with virologic suppression in PLWH on TDF-based therapy and is associated with certain participant characteristics. Further research is required to evaluate this drug adherence and exposure measure in clinical practice.

CLINICAL TRIALS REGISTRATION

NCT02012621.

Repeated rectal application of a hyperosmolar lubricant is associated with microbiota shifts but does not affect PrEP drug concentrations: results from a randomized trial in men who have sex with men

INTRODUCTION

Oral pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) is highly effective in preventing HIV infection among men who have sex with men (MSM). The effects of consistent personal lubricant use in the rectum on tissue PrEP drug concentrations and the rectal microbiota are unknown. We investigated rectal PrEP drug concentrations and the microbiota in MSM before and after repeated rectal application of a hyperosmolar lubricant.

METHODS

We randomized 60 HIV-negative MSM to apply 4 mL of hyperosmolar rectal lubricant daily (n = 20), take daily oral TDF/FTC (n = 19), or both (n = 21) for seven days. Blood, rectal biopsies and rectal secretions were collected via rigid sigmoidoscopy before and on day 8 after product use. Tenofovir (TFV) and FTC as well as their intracellular metabolites tenofovir-diphosphate (TFV-DP), FTC-triphosphate (FTC-TP) were measured by HPLC-mass spectrometry. Rectal mucosal microbiota was sequenced with 16S rRNA sequencing using Illumina MiSeq.

RESULTS

Seven days of lubricant application was not associated with differences in PrEP drug concentrations in rectal tissue or secretions. Lubricant use was associated with a decrease in the relative abundance of the Bacteroides genus (p = 0.01) and a non-significant increase in the Prevotella genus (p = 0.09) in the rectum. PrEP drug concentrations in rectal tissue and secretions were not associated with microbiota composition or diversity either before or after lubricant use.

CONCLUSIONS

Repeated rectal application of a hyperosmolar lubricant does not affect mucosal PrEP drug concentrations but is associated with changes in the rectal microbiome.

Neuroimmune Axes of the Blood-Brain Barriers and Blood-Brain Interfaces: Bases for Physiological Regulation, Disease States, and Pharmacological Interventions

Central nervous system (CNS) barriers predominantly mediate the immune-privileged status of the brain, and are also important regulators of neuroimmune communication. It is increasingly appreciated that communication between the brain and immune system contributes to physiologic processes, adaptive responses, and disease states. In this review, we discuss the highly specialized features of brain barriers that regulate neuroimmune communication in health and disease. In section I, we discuss the concept of immune privilege, provide working definitions of brain barriers, and outline the historical work that contributed to the understanding of CNS barrier functions. In section II, we discuss the unique anatomic, cellular, and molecular characteristics of the vascular blood-brain barrier (BBB), blood-cerebrospinal fluid barrier, and tanycytic barriers that confer their functions as neuroimmune interfaces. In section III, we consider BBB-mediated neuroimmune functions and interactions categorized as five neuroimmune axes: disruption, responses to immune stimuli, uptake and transport of immunoactive substances, immune cell trafficking, and secretions of immunoactive substances. In section IV, we discuss neuroimmune functions of CNS barriers in physiologic and disease states, as well as pharmacological interventions for CNS diseases. Throughout this review, we highlight many recent advances that have contributed to the modern understanding of CNS barriers and their interface functions.

Inflammation investigated as a source of pharmacokinetic variability of atazanavir in AIDS Clinical Trials Group protocol A5224s

BACKGROUND

Inflammation is associated with the downregulation of drug metabolizing enzymes and transporters. Thus, we investigated the chronic inflammatory state associated with HIV infection as a source of pharmacokinetic variability of atazanavir. We also explored the association of total bilirubin concentrations with markers of inflammation and endothelial activation.

METHODS

Apparent oral clearance (CL/F) of atazanavir was estimated from plasma samples collected from participants in AIDS Clinical Trials Group Study A5202. Several inflammatory and endothelial activation biomarkers were measured at baseline and weeks 24 and 96 as part of metabolic substudy A5224s: high-sensitivity C-reactive protein (hsCRP), interleukin-6, tumour necrosis factor-α and its soluble receptors, soluble vascular cellular and intracellular adhesion molecules and total bilirubin. Statistical analysis was performed by a matrix of correlation coefficients between atazanavir CL/F and biomarker concentrations measured at week 24. The correlation between atazanavir clearance and percentage change in bilirubin from baseline to weeks 24 and 96, and between biomarkers and bilirubin concentrations at each week were also evaluated.

RESULTS

Among 107 participants, there were no significant correlations observed between atazanavir CL/F and inflammatory and endothelial activation biomarkers measured at week 24 (P≥0.24). As expected, bilirubin increased with increasing exposure to atazanavir (rho=-0.25, P=0.01). Bilirubin concentrations were inversely correlated (P<0.01) with each of the biomarkers except hsCRP.

CONCLUSIONS

Atazanavir CL/F did not correlate with the inflammatory biomarkers changes. Inflammatory-mediated inhibition of cytochrome P450 3A may have been attenuated due to atazanavir-associated increases of bilirubin, which has known anti-inflammatory properties.

High CXCL10/IP-10 levels are a hallmark in the clinical evolution of the HIV infection

The aim of this study was to investigate the modulation of plasma CXCL10, CCL20, CCL22, CCL2, CCL17 and CCL24 levels in HIV-positive patients grouped according to extreme phenotypes of progression to AIDS, and at different stages of HIV infection. HIV-positive individuals with extreme phenotypes of AIDS progression (n=58) at different clinical stages (chronic individuals, both pre-HAART and under-HAART) and HIV-negative controls (n=20) were evaluated. Additionally, HIV-positive individuals that initiated HAART with >350CD4⁺T-cells/mm³ were compared with those who initiated treatment with <350CD4⁺T-cells/mm³. Plasma levels of six chemokines were quantified by a Luminex assay. Higher CXCL10 levels were observed in individuals immediately before their CD4⁺T-cell levels were indicative for HAART (pre-HAART), independently of their progressor status, i.e. slow (SPs) or rapid progressors (RPs). SPs pre-HAART showed higher CXCL10 levels compared to elite controllers and RPs under HAART (p_c=0.009 and p_c=0.007, respectively). CXCL10 levels were higher in SPs HAART CD4<350 (initiated HAART with <350 CD4⁺T-cells) when compared with SPs HAART CD4>350 (initiated HAART with >350 CD4⁺T-cells) (1096 vs. 360.33pg/mL, p=0.0101). Normalisation of CXCL10 levels seems to depend on the CD4⁺T-cell nadir at HAART initiation. CCL20 levels were higher in chronic SPs, SPs pre-HAART, SPs HAART and RPs HAART compared with the HIV-negative controls, indicating persistent CCL20 expression. In conclusion, our results indicate that CXCL10 levels are a hallmark in the clinical evolution of HIV infection. However, our results must be verified in a study evaluating a larger number of AIDS progressors.