Cytokines, Hepatic Fibrosis, and Antiretroviral Therapy Role in Neurocognitive Disorders HIV Related

The HIV may trigger a process of neuronal loss and axonal degeneration throughout the brain, which is carried on by the immune system releasing of proinflammatory cytokines, so that chronic inflammation associated with dysregulated innate immune response, glial cell dysfunction, and adverse antiretroviral therapy (ART) effect play an important role causing milder HIV-associated neurocognitive disorders or asymptomatic neurocognitive impairment. All patients have been tested for neurocognitive functioning through a comprehensive, five-domain neuropsychological battery performed in the study. Human cytokine (interleukin [IL]-6, IL-8, IL-18, and tumor necrosis factor [TNF]-α) and brain-derived neurotrophic factor serum levels were quantified using ELISAs, and the hepatic fibrosis was estimated using the noninvasive Fibrosis 4 (FIB-4) score. The study showed a group of 40 HIV-infected individuals and it was observed that almost 40% of HIV⁺ individuals, even if clinically asymptomatic, displayed some degree of neurocognitive dysfunction, compared to normative performance standards, at least in two cognitive areas. The functions affected the most were memory, attention, executive function, and psychomotor processing speed. Three cytokines (IL-6, IL-8, and IL-18) to be significantly linked to test results in specific neurocognitive domain were found. Treatments with nucleoside reverse transcriptase inhibitor plus non-nucleoside reverse transcriptase inhibitor alone were instead associated with poor neurocognitive outcome, especially in verbal fluency, fine motility, and Zung Depression Scale. Elevated value of FIB-4 score showed an opposite connection with cognitive performance as well, underlining the direct association between hepatic steatosis and neurocognitive deficit. The cytokine panel and the FIB-4 score can predict presence or worsening of neurocognitive functions in HIV-infected individuals. An ART switch can be suggested according to the neurocognitive domain involved the most, advising a therapy with protease inhibitors or/and integrase inhibitors to improve fluency, executive functions, and to prevent depression.

Plasma concentrations of efavirenz, darunavir/ritonavir and raltegravir in HIV-HCV-coinfected patients without liver cirrhosis in comparison with HIV-monoinfected patients

BACKGROUND

The objective of the study was to assess plasma concentrations of efavirenz, darunavir/ritonavir and raltegravir in patients with human immunodeficiency virus-hepatitis C virus (HIV-HCV)-coinfection without liver cirrhosis.

METHODS

In this observational, open-label study, adult HIV-infected outpatients treated with tenofovir/emtricitabine plus efavirenz (600 mg daily), darunavir/ritonavir (800/100 mg daily) or raltegravir (400 mg twice daily) for at least 4 weeks were asked to participate. Subjects with liver cirrhosis were excluded. The trough concentration (C trough) of darunavir/ritonavir and raltegravir and the mid-dose concentration (C12h) of efavirenz were assessed at steady state by a validated high-performance liquid chromatography (HPLC)-tandem mass spectrometry method.

RESULTS

A total of 96 HIV-positive patients were enrolled into the study. Thirty-four patients were treated with efavirenz, 33 with darunavir/ritonavir and 29 with raltegravir. The geometric mean plasma C trough [coefficient of variation (%)] of darunavir was comparable between HIV+/HCV+ and HIV+/HCV- subjects: 2644 ng/ml (155%) and 2491 ng/ml (139%), respectively (geometric mean ratio (GMR) = 0.81; 95% confidence interval (CI) = 0.79-1.56; p = 0.69). These values were comparable for raltegravir: 108 ng/ml (149%) in the HIV+/HCV+ group and 96 ng/ml (161%) in the HIV+/HCV- group (GMR = 0.84; 95% CI = 0.61-1.44; p = 0.72). On the contrary, the geometric mean plasma C12h of efavirenz was significantly higher among the 15 HIV+/HCV+ patients (1915 ng/ml, 159%) than among the 19 HIV+/HCV- patients (1505 ng/ml, 167%; GMR = 1.41; 95% CI = 1.19-1.71; p = 0.009).

CONCLUSIONS

The mean plasma concentration of efavirenz was significantly higher in HCV-positive than in HCV-negative patients without liver cirrhosis, while the mean plasma levels of darunavir/ritonavir and raltegravir were comparable in both groups.

Correlates of HIV sustained viral suppression in HIV/hepatitis C virus coinfected patients: possible role of the hepatitis C virus sustained viral response

BACKGROUND

The impact of hepatitis C virus (HCV)-related characteristics such as genotype, viral load or liver fibrosis on the chances of achieving sustained HIV suppression in coinfected patients is not fully documented.

METHOD

We examined the relationship between both HIV/HCV-related and sociobehavioural characteristics and HIV sustained viral suppression (SVS) in 897 patients included in the ANRS CO13 HEPAVIH cohort.

RESULTS

The main outcome variable was HIV SVS, defined as at least two consecutive undetectable HIV viral loads. Among the 897 HIV/HCV-coinfected patients, 419 (47%) had received HCV therapy at least once, and 103 patients (25%) had experienced an HCV sustained virologic response (SVR). In multivariate analysis, older age [odds ratio (OR) 1.23 for each period of 5 years of age, 95% confidence interval (CI) 1.02-1.49; P = 0.03], a higher level of school education (OR 1.92, 95% CI 1.04-3.56; P = 0.04), good adherence to HIV therapy (OR 2.05, 95% CI 1.23-3.43; P = 0.006) and HCV SVR (OR 1.81, 95% CI 1.01-3.26; P = 0.04) remained significantly associated with HIV SVS. In contrast, triple nucleoside reverse transcriptase inhibitor (NRTI) regimens were associated with failure to achieve HIV SVS (OR 0.50, 95% CI 0.27-0.94; P = 0.03). Our results show that HCV SVR is associated with a higher likelihood of achieving HIV SVS.

CONCLUSION

With the advent of direct-acting anti-HCV drugs, a marked increase in the rate of virologic response is observed in coinfected patients. So, further research is needed to determine whether suppression of HCV replication could be associated with a higher efficacy of antiretroviral therapy.

Increased incidence of antiretroviral drug discontinuation among patients with viremic hepatitis C virus coinfection and high hyaluronic acid, a marker of liver fibrosis

BACKGROUND

Most antiretroviral drugs are metabolized by the liver; hepatic disease or liver damage as a result of hepatitis C virus (HCV) could impair this metabolism leading to an increased risk of drug toxicity. This study aimed to determine the risk of antiretroviral drug discontinuation among HCV/HIV coinfected patients.

METHODS

EuroSIDA patients taking combination antiretroviral therapy were included. Poisson regression identified factors associated with antiretroviral treatment discontinuation.

RESULTS

A total of 9535 HIV-positive patients with known HCV status were included (6939 HCVAb-negative; 2596 HCVAb-positive at baseline). Viremic HCV infection was associated with a 44% increased risk of antiretroviral drug discontinuation compared with aviremic infection [adjusted incidence rate ratio, aIRR: 1.44 (95% confidence interval, CI 1.22-1.69)]; this relationship was largest among nonnucleoside reverse transcriptase inhibitors [aIRR: 1.59 (95% CI 1.18-2.14)]. In the subset of 935 HIV-positive patients also HCV-positive or HBV-positive with plasma hyaluronic acid measured, hyaluronic acid more than 100 ng/ml was associated with a 37% increased risk of antiretroviral drug discontinuation [aIRR: 1.37 (95% CI 1.08-1.73) vs. hyaluronic acid ≤100 ng/ml] and the effect of HCV viremia became nonsignificant; the largest drug association was seen for protease inhibitors [aIRR: 1.40 (95% CI 1.04-1.89)].

CONCLUSION

HCV viremia and high levels of hyaluronic acid predict antiretroviral drug discontinuation. Evidence was also found to suggest a link between impaired liver function and protease inhibitor toxicity.

Relevance of Liver Failure for Anti-Infective Agents: From Pharmacokinetic Alterations to Dosage Adjustments

The liver is a complex organ with great ability to influence drug pharmacokinetics. Due to its wide array of function, its impairment has the potential to affect bioavailability, enterohepatic circulation, drug distribution, metabolism, clearance, and biliary elimination. These alterations differ widely depending on the cause of the liver failure, if it is acute or chronic in nature, the extent of impairment, and comorbid conditions. In addition, effects on liver functions do not occur in a proportional or predictable manner for escalating degrees of liver impairment. The ability of hepatic alterations to influence PK is also dependent on drug characteristics, such as administration route, chemical properties, protein binding, and extraction ratio, among others. This complexity makes it difficult to predict what these effects have on drugs. Unlike certain classes of agents, efficacy of anti-infectives is most often dependent on fulfilling pharmacokinetic/pharmacodynamic targets, such as C_max/MIC, AUC/MIC, T_>MIC, IC₅₀/EC₅₀, or T>EC₉₅. Loss of efficacy, or conversely, increased risk of toxicity may occur in certain circumstances of liver injury. Although important to consider these potential alterations and their effects on specific anti-infectives, many lack data to constitute specific dosing adjustments, making it important to monitor patients for effectiveness and toxicities of therapy.

Liver function test abnormalities in Nigerian patients with human immunodeficiency virus and hepatitis B virus co-infection

Data on baseline hepatic function of HIV and hepatitis B virus (HBV) co-infected patients are limited in sub-Saharan Africa. We assessed liver function test (LFT) abnormalities in Nigerian patients with HIV/HBV co-infection to highlight the impact of HIV on HBV-related liver disease in sub-Saharan Africa. A cross-sectional study involving 100 HIV/HBV co-infected patients and 100 age- and sex-matched HBV mono-infected controls. Blood testing for HIV antibodies, CD4+ cell count, hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), LFTs, platelet count, fasting blood glucose and lipid profile were carried out. Non-invasive hepatic fibrosis scores (aspartate aminotransferase-platelet ratio index [APRI] and FIB-4) were also calculated. Co-infected patients had deranged liver enzymes more than the controls (77% versus 64%, P = 0.04). The predominant patterns of enzyme derangement in co-infected patients were either predominantly ↑ALP (30% versus 4%, P < 0.0001) or mixed (30% versus 15%, P = 0.01) but predominantly ↑AST/ALT in the controls (25% versus 9%, P = 0.003). Co-infected patients had higher fibrosis scores for both APRI (P = 0.002) and FIB-4 (P = 0.0001). On further analysis, LFT abnormalities and fibrosis scores were only significantly higher in co-infected patients in the immune clearance and HBeAg-negative chronic hepatitis phases. LFT abnormalities are common in Nigerians with HBV infection and co-infection with HIV negatively impacts on hepatic function.

Influence of chronic hepatitis C infection on cytochrome P450 3A4 activity using midazolam as an in vivo probe substrate

PURPOSE

Inflammation-related changes in pharmacokinetics have been described for a number of disease-states including cancer, infection, and autoimmune disorders. This study examined the impact of chronic hepatitis C infection (CHC) on the pharmacokinetics of the cytochrome P450 3A probe midazolam in patients without significant liver disease who were either treatment naïve or prior interferon null-responders.

METHODS

Data were pooled from three studies which compared the pharmacokinetics of oral midazolam in healthy volunteers (n = 107) and in treatment-naive patients (n = 35) and interferon-null responders (n = 24) with CHC but without significant liver disease. Oral midazolam was administered as a single 2 mg oral dose, followed by frequent pharmacokinetic sampling and determination of the pharmacokinetics of midazolam and its α-hydroxy metabolite. CYP3A activity was determined by the metabolic ratio (MR) of the AUC metabolite/AUC parent and compared across groups as the mean effect ratio (test/reference).

RESULTS

The midazolam MR was lower in treatment-naïve patients with CHC than in health volunteers with a mean effect ratio of 0.63 [90 % confidence interval (CI) 0.56-0.72]. The effect was more pronounced in null-responders, who demonstrated a mean MR effect ratio of 0.46 (90 % CI 0.39-0.53) compared to volunteers. The mean area under the concentration-time curve (AUCinf) for midazolam in healthy volunteers, naïve patients, and null-responders was 32.3 [coefficient of variation (CV%) 41], 36.5 (CV% 33.5), and 55.3 (CV% 36.9) ng.h/mL, respectively.

CONCLUSIONS

The results of this study demonstrate a reduction in CYP3A4 activity between healthy volunteers and patients with CHC, with interferon null-responders demonstrating the most substantial difference. These results may have implications for the pharmacotherapy of patients infected with CHC.

Review article: prescribing medications in patients with cirrhosis - a practical guide

BACKGROUND

Most drugs have not been well studied in cirrhosis; recommendations on safe use are based largely on experience and/or expert opinion, with dosing recommendations often based on pharmacokinetic (PK) changes.

AIM

To provide a practical approach to prescribing medications for cirrhotic patients.

METHODS

An indexed MEDLINE search was conducted using keywords cirrhosis, drug-induced liver injury, pharmacodynamics (PDs), PKs, drug disposition and adverse drug reactions. Unpublished information from the Food and Drug Administration and industry was also reviewed.

RESULTS

Most medications have not been adequately studied in cirrhosis, and specific prescribing information is often lacking. Lower doses are generally recommended based on PK changes, but data are limited in terms of correlating PD effects with the degree of liver impairment. Very few drugs have been documented to have their hepatotoxicity potential enhanced by cirrhosis; most of these involve antituberculosis or antiretroviral agents used for HIV or viral hepatitis. Paracetamol can be used safely when prescribed in relatively small doses (2-3 g or less/day) for short durations, and is recommended as first-line treatment of pain. In contrast, NSAIDs should be used cautiously (or not at all) in advanced cirrhosis. Proton pump inhibitors have been linked to an increased risk of spontaneous bacterial peritonitis (SBP) in cirrhosis and should be used with care.

CONCLUSIONS

Most drugs can be used safely in cirrhosis, including those that are potentially hepatotoxic, but lower doses or reduced dosing frequency is often recommended, due to altered PKs. Drugs that can precipitate renal failure, gastrointestinal bleeding, SBP and encephalopathy should be identified and avoided.

Neutropenia during therapy with peginterferon and ribavirin in HIV-infected subjects with chronic hepatitis C and the risk of infections

BACKGROUND

It is unclear whether pegylated interferon (peg-IFN) -induced neutropenia in subjects coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) is associated with increased risk of serious infections.

METHODS

This was a prospective cohort study conducted between 2000 and 2012 in HIV/HCV-coinfected subjects initiating treatment with peg-IFN plus ribavirin (RBV). Infections were defined as serious when patients required hospitalization, treatment was discontinued, or the patient died. The association between neutropenia (severe, <500 cells/μL; nonsevere, 500 -1500 cells/μL) and infections (serious infections and infections of any severity) was determined by logistic regression analysis.

RESULTS

Among 418 subjects (3928 person-weeks of therapy), infections occurred in 123 (29%), accounting for 149 episodes (3.8 infections per 100 person-weeks of therapy). Most infections (47%) involved the upper respiratory tract and were minor. After a multivariate analysis adjusted by age, sex, CD4 count, AIDS, antiretroviral therapy, cirrhosis, neutrophil count, type of peg-IFN, and granulocyte colony-stimulating factor use, none of these variables remained independently associated with the risk of infection. Twenty subjects developed a serious infection (4.8% of all patients). The frequency of serious infections was higher in subjects with severe neutropenia compared to those with nonsevere neutropenia and without neutropenia, although it was not statistically significant (8.6%, 4.8%, and 3.6%, respectively; trend test P = .281). In multivariate analysis, neutropenia was not independently associated with increased risk of serious infections.

CONCLUSIONS

In this large prospective cohort of HIV/HCV-coinfected patients treated with peg-IFN plus RBV, serious infections were uncommon, nonfatal, and unrelated to peg-IFN -induced severe neutropenia.

Pharmacological and clinical evidence of nevirapine immediate- and extended-release formulations

We reviewed the current information available on nevirapine immediate- and extended-release formulations and its role in single-dose and combination antiretroviral therapy. Nevirapine was approved in 1996 and was the first non-nucleoside reverse-transcriptase inhibitor available for the treatment of HIV-1 infection. Nevirapine has demonstrated good efficacy and a well-characterized safety profile. A major drawback is the low genetic barrier, allowing the emergence of resistance in the presence of single mutations in the reverse-transcriptase gene. This shortcoming is particularly relevant when nevirapine is administered in a single dose to prevent mother-to-child transmission of HIV-1 infection, compromising the efficacy of future non-nucleoside reverse transcriptase-inhibitor regimens. Studies published recently have probed the noninferiority of nevirapine compared to ritonavir-boosted atazanavir with both tenofovir disoproxil fumarate and emtricitabine in antiretroviral treatment-naïve patients. In 2011, a new formulation of nevirapine (nevirapine extended release) that allowed once-daily dosing was approved by the Food and Drug Administration and by the European Medicines Agency. VERxVe, a study comparing nevirapine extended release with nevirapine immediate release in antiretroviral treatment-naïve patients, and TRANxITION, a study carried out in antiretroviral treatment-experienced patients who switched therapy from nevirapine immediate release to nevirapine extended release, provided data on the noninferiority of the new formulation of nevirapine compared with nevirapine immediate release in terms of efficacy and safety. Nevirapine extended release will further increase the durability and persistence of nevirapine-containing antiretroviral therapy, allowing once-daily dosing regimens.

Safety and pharmacokinetics of lopinavir in HIV/HCV coinfected patients with advanced liver disease

PURPOSE

There are few data about the safety and pharmacokinetics of lopinavir in HIV/HCV coinfected patients with very advanced liver disease.

METHOD

Prospective study of 60 HIV/HCV coinfected patients who underwent a liver biopsy and received a lopinavir-based regimen. The rate of hepatotoxiciy and plasma trough levels were determined in absence/presence of cirrhosis (25 cases), especially in 11 patients with Child-Pugh stage B-C.

RESULTS

Overall, geometric mean level of lopi-navir was 7,109 ng/mL (interquartile range [IQR], 5,163-9,029), without differences according to cirrhosis (7,662; IQR, 5,165-10,442) or not (6,708; IQR, 5,524-8,526; P = .6). In 11 patients with Child-Pugh stage B-C, trough level was 9,640 ng/mL (IQR, 1,620-11,622 ng/mL), but there was a 99% interpatient variability (72 to 13,331 ng/mL). During a follow-up of 195.2 patient-years, there were 7 cases of hepatotox-icity, with an incidence of 3.39 episodes/100 patient-years (2.2 to 7.9). This incidence was higher in patients with Child-Pugh stage B-C (5.43 episodes/100 patient-years). There were no differences in lopinavir trough levels between patients with or without liver toxicity (7,100 vs 7,119 ng/mL; P = .9).

CONCLUSION

The risk of lopinavir-associated hepatotoxicity in patients with very advanced liver disease is low. However, lopinavir plasma trough levels are increased, and there is a high interpatient variability.