Low incidence of hepatotoxicity in a cohort of HIV patients treated with lopinavir/ritonavir

Differences in genetic variants in lopinavir disposition among HIV-infected Bantu Africans

INTRODUCTION

Variability in lopinavir (LPV) plasma concentration among patients could be due to genetic polymorphisms. This study set to evaluate significance of variants in CYP3A4/5, SLCO1B1 and ABCC2 on LPV plasma concentration among African HIV-positive patients.

MATERIALS & METHODS

Eighty-six HIV-positive participants on ritonavir (LPV/r) were genetically characterized and LPV plasma concentration determined.

RESULTS & DISCUSSION

LPV plasma concentrations differed >188-fold (range 0.0206-38.6 µg/ml). Both CYP3A4*22 and SLCO1B1 rs4149056G (c.521C) were not observed in this cohort. CYP3A4*1B, CYP3A5*3, CYP3A5*6 and ABCC2 c.1249G>A which have been associated with LPV plasma concentration, showed no significant association.

CONCLUSION

These findings highlight the need to include African groups in genomics research to identify variants of pharmacogenomics significance.

Progression of Liver Fibrosis and Modern Combination Antiretroviral Therapy Regimens in HIV-Hepatitis C-Coinfected Persons

In human immunodeficiency virus–hepatitis C-coinfected, both protease inhibitor- and nonnucleoside reverse transcriptase inhibitor-based regimens were associated with progression of liver fibrosis over time when paired with a backbone of abacavir/lamivudine but not tenofovir/emtricitabine.

Background. Liver diseases progress faster in human immunodeficiency virus (HIV)–hepatitis C virus (HCV)-coinfected persons than HIV-monoinfected persons. The aim of this study was to compare rates of liver fibrosis progression (measured by the aspartate-to-platelet ratio index [APRI]) among HIV-HCV–coinfected users of modern protease inhibitor (PI)- and nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimens with a backbone of tenofovir/emtricitabine (TDF/FTC) or abacavir/lamivudine (ABC/3TC).

Methods. Data from a Canadian multicenter cohort study were analyzed, including 315 HCV polymerase chain reaction–positive persons who initiated antiretroviral therapy with a PI or NNRTI and a backbone containing either TDF/FTC or ABC/3TC. Multivariate linear regression analyses with generalized estimating equations were performed after propensity score matching to balance covariates across classes of anchor agent.

Results. A backbone of TDF/FTC was received by 67% of PI users and 69% of NNRTI users. Both PI and NNRTI use was associated with increases in APRI over time when paired with a backbone of ABC/3TC: 16% per 5 years (95% confidence interval [CI], 4%, 29%) and 11% per 5 years (95% CI, 2%, 20%), respectively. With TDF/FTC use, no clear association was found among PI users (8% per 5 years, 95% CI, −3%, 19%) or NNRTI users (3% per 5 years, 95% CI, −7%, 12%).

Conclusions. Liver fibrosis progression was more influenced by the backbone than by the class of anchor agent in HIV-HCV–coinfected persons. Only ABC/3TC-containing regimens were associated with an increase of APRI score over time, regardless of the class of anchor agent used.

Abnormal liver stiffness assessed using transient elastography (Fibroscan®) in HIV-infected patients without HBV/HCV coinfection receiving combined antiretroviral treatment

Background and Aims

Liver stiffness measurement (LSM) using transient elastography (Fibroscan®) can identify individuals with potential underlying liver disease. We evaluated the prevalence of abnormal LSM values as assessed using LSM and its predictors in HIV-infected asymptomatic patients receiving combined antiretroviral treatment (cART) without HBV/HCV coinfection.

Methods

We prospectively recruited 93 patients who had consistently been undergoing cART for more than 12 months at Severance Hospital in Seoul, Republic of Korea, from June to December 2010. LSM values >5.3 kPa were defined as abnormal.

Results

Thirty-nine (41.9%) had abnormal LSM values. On multivariate correlation analysis, the cumulative duration of boosted and unboosted protease inhibitors (PIs) were the independent factors which showed a negative and positive correlation to LSM values, respectively (β = –0.234, P = 0.023 and β = 0.430, P<0.001). In multivariate logistic regression analysis, the cumulative exposure duration of boosted-PIs and γ-glutamyltranspeptidase levels were selected as the independent predictors which showed a negative and positive correlation with abnormal LSM values, respectively (odds ratio [OR], 0.941; 95% confidence interval [CI], 0.889–0.997; P = 0.039 and OR, 1.032; 95% CI, 1.004–1.060; P = 0.023).

Conclusion

The high percentage of HIV-infected asymptomatic patients receiving cART without HBV/HCV coinfection had abnormal LSM values. The cumulative exposure duration of boosted-PIs and γ-GT level were independent predictors which showed a negative and positive correlation with abnormal LSM values, respectively.

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.

CYP3A4-mediated lopinavir bioactivation and its inhibition by ritonavir

The combination of lopinavir (LPV) and ritonavir (RTV) is one of the preferred regimens for the treatment of HIV infection with confirmed efficacy and relatively low toxicity. LPV alone suffers the poor bioavailability due to its rapid and extensive metabolism. RTV boosts the plasma concentration of LPV by suppressing its metabolism and thus increasing LPV efficacy. In the current study, we found that RTV also inhibits LPV bioactivation. LPV bioactivation was investigated in human liver microsomes and cDNA-expressed human cytochromes P450. Twelve GSH-trapped reactive metabolites of LPV were identified by using a metabolomic approach. Semicarbazide-trapped reactive metabolites of LPV were also detected. RTV effectively suppressed all pathways of LPV bioactivation via CYP3A4 inhibition. Our data together with previous reports suggest that LPV plus RTV is an ideal combination because RTV not only boosts LPV plasma concentration, but it decreases LPV bioactivation.

HIV-related liver disease: ARV drugs, coinfection, and other risk factors

Highly-active antiretroviral therapy (HAART) has proven remarkably effective for prolonging the life of patients with human immunodeficiency virus (HIV). However, while most HAART agents are safe, many have the potential to cause liver toxicity. Physicians must therefore consider the possibility of drug-induced liver injury in the management of HIV-infected patients, especially those with certain risk factors such as coinfection with hepatitis B virus (HBV) or hepatitis C virus (HCV), female gender, alcohol abuse, older age, or obesity. Understanding how, when, and why drug-related liver damage occurs is key to managing these patients safely and effectively. Knowledge of HAART-related liver effects will help ensure that patients receive the most benefit with the least toxicity from any given drug regimen. As more information about the mechanisms of drug related liver injury is known, clinicians will be better able to tailor therapies to suit individual situations, resulting in greater patient safety and outcomes.

Drug-induced liver injury associated with HIV medications

Antiretroviral therapy (ART) for HIV infection frequently has been associated with elevated liver enzyme levels. Determining the cause of elevated liver enzyme levels in patients who have HIV is difficult because ART usually consists of three different drugs, patients may be taking additional hepatotoxic medications and patients who have HIV often suffer from other liver diseases. Several agents, however, are recognized as having noteworthy and specific patterns of toxicity. This article reviews the different HIV drug classes, incidence of elevated liver enzyme values by class and by individual drug, risk factors, specific toxicities, and possible mechanisms of injury.

Risk factors for grade 3-4 liver enzyme elevation in HIV and hepatitis C coinfected patients on combination antiretroviral therapy

Although coinfection with hepatitis C (HCV) is an established risk factor for hepatotoxicity in HIV-positive patients receiving combination antiretroviral therapy (cART), specific variables that may be predictive of severe hepatotoxicity among co-infected patients receiving cART remain poorly defined. A retrospective cohort study of HIV/HCV coinfected adults from two HIV treatment centers covering the period between December 1998 and December 2003 was conducted to address this question. The primary endpoint of the study was the occurrence of grade 3 or 4 elevation of serum alanine aminotransferase (ALT) during follow-up and the primary predictors of interest were specific antiretrovirals. One hundred five coinfected patients receiving cART for a median of 70 months (interquartile range [IQR], 37, 83) were included in the analysis. Twenty-three (22%) patients developed a grade 3 or 4 increase in serum ALT at least once in follow-up. In univariate analysis, current receipt of lopinavir/ritonavir (LPV/r) (odds ratio [OR] 3.09, 95% confidence interval [CI] 1.14-8.34, p = 0.03), baseline ALT (OR 1.01, 95% CI 1.00-1.02, p = 0.004), and current use of boosting ritonavir (OR 2.84, 95% CI 1.16-7.00, p = 0.02) were significantly associated with a grade 3 or 4 increase in serum ALT, although most patients receiving boosting ritonavir were on lopinavir/ritonavir based regimens. Patients receiving LPV/r had been previously exposed to significantly more antiretrovirals (p < 0.0001), protease inhibitors (p < 0.0001), and nucleoside analogues (p = 0.0009) compared to the rest of the cohort. Further research to better clarify risk factors for hepatotoxicity in coinfected patients is warranted given the challenges in treating this population.

Low incidence of severe liver events in HIV patients with and without hepatitis C or B coinfection receiving lopinavir/ritonavir

OBJECTIVES

To analyze the incidence of severe liver events in HIV patients treated with lopinavir/ritonavir and the role of coinfection in the development of this toxicity.

METHOD

This was a retrospective, multicenter, cohort study of all HIV-positive patients who started a regimen of HAART that included lopinavir/ritonavir (LPV/r). The main outcome variable was the emergence of a severe liver event, defined as decompensation of pre-existing chronic liver disease and grade 3-4 hypertransaminasemia (HT), that is, plasma AST or ALT values >5 times above the upper limit of normality, if baseline levels were normal, or >3.5 times the baseline values when they were abnormal.

RESULTS

388 HIV-infected patients were included, with a median follow-up of 25.6 months. Coinfection with HCV was present in 61% of the patients and with HBV in 6.7%. There were 6 cases of severe liver events, all involving patients who were coinfected with HCV and all within the first 6 months. This represents 0.72 events per 100 patient-years (95% confidence interval [CI] 0.36-2.98) and 1.21 events per 100 patient-years (95% CI 0.60-5.86) in coinfected patients. The only factors associated with severe liver events at 6 months were baseline HT and HCV coinfection.

CONCLUSION

The incidence of severe hepatic events in HIV-positive patients receiving a HAART regimen including LPV/r was very low, even in coinfected patients. HCV coinfection and baseline HT were the only factors associated with severe liver events. LPV/r can be considered a safe and well-tolerated option in HIV patients with hepatotropic virus coinfections.

Liver toxicity induced by non-nucleoside reverse transcriptase inhibitors

Liver toxicity is one of the most relevant adverse effects of antiretroviral therapy. Within the non-nucleoside reverse transcriptase inhibitors (NNRTIs), efavirenz can be considered a safer drug for the liver than nevirapine. In fact, the frequency of severe increased liver enzymes in patients on efavirenz ranges from 1 to 8%, whereas in patients treated with nevirapine, it ranges from 4 to 18%. Likewise, nevirapine is more commonly associated than efavirenz with early acute hepatitis, which is produced by a hypersensitivity mechanism and has a defined risk profile that often makes it avoidable. Despite the fact that most cases of NNRTI-induced liver toxicity are asymptomatic, the rates of symptomatic events in patients treated with nevirapine are greater than in subjects on efavirenz. In any case, it is unusual for an NNRTI to be suspended due to liver toxicity.

Non-nucleoside reverse transcriptase inhibitors: a review

Non-nucleoside reverse transcriptase inhibitors form the backbone of antiretroviral treatment for many HIV-infected individuals. The tolerability, pill burden and efficacy associated with this class of agents make them a frequent choice for first-line therapy. Here we review nevirapine and efavirenz in terms of efficacy, resistance and toxicity, focusing particularly on the use of nevirapine to prevent mother-to-child transmission in developing countries.

Antiretroviral medication considerations for individuals coinfected with HIV and hepatitis C virus

There is great need to treat HIV/hepatitis C virus (HCV)-coinfected individuals with both antiretroviral and anti-HCV pharmacotherapy. However, treatment for HIV may lead to hepatotoxicity, and there are potential interactions and synergistic effects between antiretrovirals and anti-HCV medications. The ideal antiretroviral therapy options for coinfected patients, in the setting of anti-HCV treatment, are unclear and present important challenges to clinicians. We review the current data on the use of antiretrovirals in HIV/HCV-coinfected patients and offer evidence-based recommendations on optimal selection and dosing of antiretroviral agents for this population.

Drug-induced liver disease

PURPOSE OF REVIEW

To summarize the pertinent case reports, case series and clinical studies that described clinical, histological, epidemiological and mechanistic features of drug-induced liver disease in 2005.

RECENT FINDINGS

Acetaminophen, highly active antiretroviral therapy and drugs for tuberculosis retained their preeminent position as the most commonly reported agents causing drug-induced liver disease, with acetaminophen continuing to be the leading cause of acute liver failure in the USA. While the frequency of drug-induced liver disease remains low, a large case-series of acute drug-induced liver disease from Spain and Sweden supported the observation that acute hepatocellular jaundice from a drug is associated with death or the need for transplant in at least 10% (known as Hy's Law). With respect to using potentially hepatotoxic medications in patients with underlying liver disease, statins and second-generation thiazolidinediones were shown to be safe when used in patients with elevated baseline alanine aminotransferase or aspartate aminotransferase levels.

SUMMARY

Drug-induced liver disease remains an important cause of acute liver failure, and research efforts by the National Institutes of Health and others are underway to better determine the risk factors and other host susceptibilities that will allow for the safer use of drugs in the future.