Severe hepatic failure related to nevirapine treatment

Singularities of nevirapine metabolism: from sex-dependent differences to idiosyncratic toxicity

Nevirapine (NVP) is a first-generation non-nucleoside reverse transcriptase inhibitor widely used for the treatment and prophylaxis of human immunodeficiency virus infection. The drug is taken throughout the patient's life and, due to the availability of an extended-release formulation, it is administered once daily. This antiretroviral is one of the scarce examples of drugs with prescription criteria based on sex, in order to prevent adverse reactions. The therapy with NVP has been associated with potentially life-threatening liver and idiosyncratic skin toxicity. Multiple evidence has emerged regarding the formation of electrophilic NVP metabolites as crucial for adverse idiosyncratic reactions. The formation of reactive metabolites that yield covalent adducts with proteins has been demonstrated in patients under NVP-based treatment. Interestingly, several pharmacogenetic- and sex-related factors associated with NVP toxicity can be mechanistically explained by an imbalance toward increased formation of NVP-derived reactive metabolites and/or impaired detoxification capability. Moreover, the haptenation of self-proteins by these reactive species provides a plausible link between NVP bioactivation and immunotoxicity, further supporting the relevance of this toxicokinetics hypothesis. In the current paper, we review the existing knowledge and recent developments on NVP metabolism and their relation to NVP toxicity.

Updated US Public Health Service guidelines for the management of occupational exposures to human immunodeficiency virus and recommendations for postexposure prophylaxis

This report updates US Public Health Service recommendations for the management of healthcare personnel (HCP) who experience occupational exposure to blood and/or other body fluids that might contain human immunodeficiency virus (HIV). Although the principles of exposure management remain unchanged, recommended HIV postexposure prophylaxis (PEP) regimens and the duration of HIV follow-up testing for exposed personnel have been updated. This report emphasizes the importance of primary prevention strategies, the prompt reporting and management of occupational exposures, adherence to recommended HIV PEP regimens when indicated for an exposure, expert consultation in management of exposures, follow-up of exposed HCP to improve adherence to PEP, and careful monitoring for adverse events related to treatment, as well as for virologic, immunologic, and serologic signs of infection. To ensure timely postexposure management and administration of HIV PEP, clinicians should consider occupational exposures as urgent medical concerns, and institutions should take steps to ensure that staff are aware of both the importance of and the institutional mechanisms available for reporting and seeking care for such exposures. The following is a summary of recommendations: (1) PEP is recommended when occupational exposures to HIV occur; (2) the HIV status of the exposure source patient should be determined, if possible, to guide need for HIV PEP; (3) PEP medication regimens should be started as soon as possible after occupational exposure to HIV, and they should be continued for a 4-week duration; (4) new recommendation-PEP medication regimens should contain 3 (or more) antiretroviral drugs (listed in Appendix A ) for all occupational exposures to HIV; (5) expert consultation is recommended for any occupational exposures to HIV and at a minimum for situations described in Box 1 ; (6) close follow-up for exposed personnel ( Box 2 ) should be provided that includes counseling, baseline and follow-up HIV testing, and monitoring for drug toxicity; follow-up appointments should begin within 72 hours of an HIV exposure; and (7) new recommendation-if a newer fourth-generation combination HIV p24 antigen-HIV antibody test is utilized for follow-up HIV testing of exposed HCP, HIV testing may be concluded 4 months after exposure ( Box 2 ); if a newer testing platform is not available, follow-up HIV testing is typically concluded 6 months after an HIV exposure.

Differences in nevirapine biotransformation as a factor for its sex-dependent dimorphic profile of adverse drug reactions

OBJECTIVES

Nevirapine is widely used for the treatment of HIV-1 infection; however, its chronic use has been associated with severe liver and skin toxicity. Women are at increased risk for these toxic events, but the reasons for the sex-related differences are unclear. Disparities in the biotransformation of nevirapine and the generation of toxic metabolites between men and women might be the underlying cause. The present work aimed to explore sex differences in nevirapine biotransformation as a potential factor in nevirapine-induced toxicity.

METHODS

All included subjects were adults who had been receiving 400 mg of nevirapine once daily for at least 1 month. Blood samples were collected and the levels of nevirapine and its phase I metabolites were quantified by HPLC. Anthropometric and clinical data, and nevirapine metabolite profiles, were assessed for sex-related differences.

RESULTS

A total of 52 patients were included (63% were men). Body weight was lower in women (P = 0.028) and female sex was associated with higher alkaline phosphatase (P = 0.036) and lactate dehydrogenase (P = 0.037) levels. The plasma concentrations of nevirapine (P = 0.030) and the metabolite 3-hydroxy-nevirapine (P = 0.035), as well as the proportions of the metabolites 12-hydroxy-nevirapine (P = 0.037) and 3-hydroxy-nevirapine (P = 0.001), were higher in women, when adjusted for body weight.

CONCLUSIONS

There was a sex-dependent variation in nevirapine biotransformation, particularly in the generation of the 12-hydroxy-nevirapine and 3-hydroxy-nevirapine metabolites. These data are consistent with the sex-dependent formation of toxic reactive metabolites, which may contribute to the sex-dependent dimorphic profile of nevirapine toxicity.

Rash and hepatitis within days of starting a new antiretroviral regimen: nevirapine hypersensitivity, secondary syphilis or both?

We report a case in which an HIV-positive man developed general malaise, skin rash and biochemical hepatitis within days of starting a nevirapine-based antiretroviral treatment regimen. At the same time, his syphilis serology proved positive. We discuss the diagnostic dilemma: was this a nevirapine hypersensitivity reaction, secondary syphilis or both?

A unifying ontology to integrate histological and clinical observations for drug-induced liver injury

Drug-induced liver injury (DILI) may present any morphologic characteristic of acute or chronic liver disease with no standardized terminology in place. Defining lexemes of DILI histopathology would allow the development of advanced knowledge discovery and data mining tools for across comparisons of publicly available information. For these purposes, a DILI ontology (DILIo) was developed by using the Unified Medical Language System tool and the standardized terminology of the Systematized Nomenclature of Medicine-Clinical Terms (SNOMED CT). The DILIo was entrained on findings of 114 US Food and Drug Administration-approved drugs by extracting all clinically DILI-related histopathologic descriptions for 1082 liver biopsy samples, which were then analyzed using the Unified Medical Language System MetaMap and subsequently mapped to the SNOMED CT. The DILIo provides a standard means to describe and organize liver injury induced by drugs, enabling comparative analysis of drugs within and across histopathologic terms. The analysis showed that flutamide, troglitazone, diclofenac, isoniazid, and tamoxifen were reported to have the most diverse histopathologic observations in liver biopsy. Necrosis, cholestasis, fatty degeneration, fibrosis, infiltrate, and hepatic necrosis were the most frequent terms used as descriptors of histopathologic features of DILI. In conclusion, DILIo entrains different algorithms for an efficient meta-analysis of published findings for an improved understanding of mechanisms and clinical characteristics of DILI.

Cohort studies: to what extent can they inform treatment guidelines?

PURPOSE OF REVIEW

This review examines situations in which information from cohort studies has proved to be useful for the development of treatment guidelines.

RECENT FINDINGS

Although there are several reasons why randomized controlled trials (RCTs) are felt to provide the most robust evidence for treatment guidelines, they may suffer from insufficient duration of follow-up, inadequate power to consider differences in important adverse events and highly selected patient populations. Furthermore, as most RCTs are performed for licensing purposes, strategic treatment decisions often lack supportive evidence from RCTs. Although data from cohort studies may be used to complement information from RCTs, cohort studies themselves are susceptible to several biases (most notably confounding) which may limit their findings. However, in the HIV field, information from such studies has been influential in guiding decisions relating to when to start highly active antiretroviral therapy, what drugs to use in the initial highly active antiretroviral therapy regimen and when to switch highly active antiretroviral therapy should virological failure occur.

SUMMARY

Given the biases that may be present, caution should be exercised when interpreting findings from cohort studies, particularly if comparisons are made of treatment strategies that involve some element of patient or clinician choice.

Risk factors for treatment-limiting toxicities in patients starting nevirapine-containing antiretroviral therapy

BACKGROUND

This collaboration of seven observational clinical cohorts investigated risk factors for treatment-limiting toxicities in both antiretroviral-naive and experienced patients starting nevirapine-based combination antiretroviral therapy (NVPc).

METHODS

Patients starting NVPc after 1 January 1998 were included. CD4 cell count at starting NVPc was classified as high (>400/microl/>250/microl for men/women, respectively) or low. Cox models were used to investigate risk factors for discontinuations due to hypersensitivity reactions (HSR, n = 6547) and discontinuation of NVPc due to treatment-limiting toxicities and/or patient/physician choice (TOXPC, n = 10,186). Patients were classified according to prior antiretroviral treatment experience and CD4 cell count/viral load at start NVPc. Models were stratified by cohort and adjusted for age, sex, nadir CD4 cell count, calendar year of starting NVPc and mode of transmission.

RESULTS

Median time from starting NVPc to TOXPC and HSR were 162 days [interquartile range (IQR) 31-737] and 30 days (IQR 17-60), respectively. In adjusted Cox analyses, compared to naive patients with a low CD4 cell count, treatment-experienced patients with high CD4 cell count and viral load more than 400 had a significantly increased risk for HSR [hazard ratio 1.45, confidence interval (CI) 1.03-2.03] and TOXPC within 18 weeks (hazard ratio 1.34, CI 1.08-1.67). In contrast, treatment-experienced patients with high CD4 cell count and viral load less than 400 had no increased risk for HSR 1.10 (0.82-1.46) or TOXPC within 18 weeks (hazard ratio 0.94, CI 0.78-1.13).

CONCLUSION

Our results suggest it may be relatively well tolerated to initiate NVPc in antiretroviral-experienced patients with high CD4 cell counts provided there is no detectable viremia.

A new era of antiretroviral drug toxicity

The spectrum of drugs used in HIV-infected patients has dramatically changed since triple antiretroviral combinations were introduced, albeit at the expense of some severe adverse events, in 1996. Abandonment of stavudine in countries that can afford it, new drugs from new classes with a wide therapeutic window and the impressive scale-up of drug access in resource-limited settings are several of the key new events. Drug safety is likely to be the most important factor to distinguish one antiretroviral regimen from another. We review life-threatening adverse events, adverse events of new investigational or recently marketed drugs, adverse events with a genetic component and tissue-specific adverse events of fat, heart, bone, kidney and liver.

Role of Metabolism in Drug-Induced Idiosyncratic Hepatotoxicity

Rare adverse reactions to drugs that are of unknown etiology, or idiosyncratic reactions, can produce severe medical complications or even death in patients. Current hypotheses suggest that metabolic activation of a drug to a reactive intermediate is a necessary, yet insufficient, step in the generation of an idiosyncratic reaction. We review evidence for this hypothesis with drugs that are associated with hepatotoxicity, one of the most common types of idiosyncratic reactions in humans. We identified 21 drugs that have either been withdrawn from the U.S. market due to hepatotoxicity or have a black box warning for hepatotoxicity. Evidence for the formation of reactive metabolites was found for 5 out of 6 drugs that were withdrawn, and 8 out of 15 drugs that have black box warnings. For the other drugs, either evidence was not available or suitable studies have not been carried out. We also review evidence for reactive intermediate formation from a number of additional drugs that have been associated with idiosyncratic hepatotoxicity but do not have black box warnings. Finally, we consider the potential role that high dosages may play in these adverse reactions.

Postexposure prophylaxis: a guide for prevention of human immunodeficiency virus transmission in orthopedic surgery

Approximately half of orthopedic surgeons reported operating on at least 1 patient with known HIV infection. Knowledge of postexposure prophylaxis guidelines may prevent HIV transmission and avert unnecessary exposure to antiretroviral agents.

Antiretroviral regimens for patients with HIV who fail first-line antiretroviral therapy

BACKGROUND

Highly active antiretroviral therapy has reduced the morbidity and mortality of patients with HIV/AIDS. A common first-line ART regimen includes a non-nucleoside reverse transcriptase inhibitor (NNRTI) and two nucleoside reverse transcriptase inhibitors (NRTIs). If treatment failure occurs, a change to second-line therapy is necessary.

OBJECTIVES

This meta-analysis aimed to assess the optimum antiretroviral regimen for patients with HIV who fail first-line therapy (ART-naive) with d4T+3TC+NVP; d4T+3TC+EFV; ZDV+3TC+NVP; and ZDV+3TC+EFV.

SEARCH STRATEGY

Electronic databases and conference proceedings were searched with relevant search terms without limits to language.

SELECTION CRITERIA

Randomised controlled trials of HIV-infected adult patients administered second-line ART after virologic failure of a first-line regimen were included. The primary outcome measure included the proportion of patients achieving undetectable plasma HIV RNA concentration (viral load). Secondary outcome measures included change in mean CD4 cell count, clinical resolution of symptoms, rate of adverse events, rate of change in therapy for failure, rate of change in therapy for toxicity, and mortality.

DATA COLLECTION AND ANALYSIS

Two authors assessed each reference for inclusion and exclusion criteria established a priori. Data were abstracted independently using a standardised abstraction form.

MAIN RESULTS

Twenty-one records were identified in total, 6 of which were duplicates. None of the records met inclusion criteria.

AUTHORS' CONCLUSIONS

There is insufficient evidence to evaluate second-line therapies in patients with HIV who fail first-line treatment with d4T+3TC+NVP; d4T+3TC+EFV; ZDV+3TC+NVP; and ZDV+3TC+EFV. Current recommendations are based on available resources and results from individualised treatment decisions based on resistance testing and clinician choice.

Effects of immunosuppressive drugs on HIV infection: implications for solid-organ transplantation

With the advent of highly active antiretroviral therapy (HAART), HIV infection has become a chronic disease. Various end-stage organ failures have now become common co-morbidities and are primary causes of mortality in HIV-infected patients. Solid-organ transplantation therefore has been proposed to these patients, as HIV infection is not anymore considered an absolute contraindication. The initial results of organ transplantation in HIV-infected patients are encouraging with no differences in patient and graft survival compared with non-HIV-infected patients. The use of immunosuppressive drug therapy in HIV-infected patients has so far not shown major detrimental effects, and some drugs in combination with HAART have even demonstrated possible beneficial effects for specific HIV settings. Nevertheless, organ transplantation in HIV-infected patients remains a complex intervention, and more studies will be required to clarify open questions such as long-term effects of drug interactions between antiretroviral and immunosuppressive drugs, outcome of recurrent HCV infection in HIV-infected patients, incidence of graft rejection, or long-term graft and patient survival. In this article, we first review the immunological pathogenesis of HIV infection and the rationale for using immunosuppression combined with HAART. We then discuss the most recent results of solid-organ transplantation in HIV-infected patients.

Determinants of nevirapine hypersensitivity and its effect on the association between hepatitis C status and mortality in antiretroviral drug-naive HIV-positive patients

OBJECTIVE

To assess risks factors and outcomes associated with nevirapine hypersensitivity reactions, and to determine the effect of hypersensitivity as a modifier of the association between hepatitis C virus (HCV) infection and mortality among antiretroviral drug-naive patients.

METHODS

The primary endpoint was hypersensitivity reactions in a population-based cohort of antiretroviral therapy-naive HIV-individuals, 18 years or older in British Columbia, Canada, who started triple antiretroviral therapy with nevirapine between May 1997 and June 2003. Univariate and multivariate analyses were performed to identify predictors of nonaccidental mortality in the subgroup of patients with known HCV serostatus.

RESULTS

A total of 66 (9.6%) of 685 patients met the definition for hypersensitivity reactions. In the univariate logistic regression analysis, no variables were identified as risk factors. In multivariate survival analyses conducted to identify characteristics associated with nonaccidental mortality, patients with both HCV coinfection and hypersensitivity reactions had a higher risk of death (hazard ratio, 7.12; 95% confidence interval, 2.73-18.53; P < 0.001) compared with those who did not have HCV coinfection or hypersensitivity reaction.

CONCLUSION

Results of this study suggest that the hypersensitivity reaction behaves as an effect modifier of the association between HCV infection and mortality in this cohort of antiretroviral drug-naive HIV-positive patients. These results support the current recommendation against the use of nevirapine in HIV/HCV-coinfected patients.

Risk of Discontinuation of Nevirapine due to Toxicities in Antiretroviral-Naive and -Experienced HIV-Infected patients with High and Low CD4+ T-cell Counts

Introduction

It is unknown whether the increased risk of toxicities in antiretroviral-naive HIV-infected patients initiating nevirapine-based (NVPc) combination antiretroviral therapy (cART) with high CD4+ T-cell counts is also observed when NVPc is initiated in cART-experienced patients.

Patients and methods

1,571 EuroSIDA patients started NVPc after 1/1/1999, with CD4+ T-cell counts and viral load measured in the 6 months before starting treatment, and were stratified into four groups based on CD4+ T-cell counts at initiation of NVPc (high [H], >400/mm3 or >250/mm3 for male or female, respectively, or low [L], ≤400/mm3 or ≤250/mm3 for male or female) and prior antiretroviral experience (antiretroviral-naive [N] or -experienced [E]). Cox proportional hazards models compared the risks of discontinuation of nevirapine due to toxicities or patient/physician choice (TOXPC).

Results

After adjustment, there was a significantly lower risk of discontinuation of nevirapine due to TOXPC in the HE group ( n=588; proportion discontinued by 3/12 months: 10/17%, respectively) than in HN (n=62; 21/32% respectively; overall relative hazard [RH]: 0.56; 95% confidence interval [CI]: 0.34–0.94; P=0.027). This difference was most pronounced during the first 3 months of NVPc (RH: 0.44; 95% CI: 0.23–0.87; P=0.017). There were no deaths in the 6 months after starting NVPc resulting from exposure to <3 months of NVPc exposure within the HE group (incidence: 0; per 1,000 person-years follow up; 95% CI: 0–6.9). After adjustment, there were no differences between the HE and HN groups in discontinuation due to TOXPC in patients starting efavirenz-based cART (RH: 0.91; 95% CI: 0.60–1.38; P=0.66) or protease-inhibitor-based cART (RH: 1.13; 95% CI: 0.77–1.66; P=0.52).

Conclusions

Results from this non-randomized study suggest that NVPc might be safer to initiate in antiretro-viral-experienced than in antiretroviral-naive patients with high CD4+T-cell counts.

Growing importance of liver disease in HIV-infected persons

Liver disease is a growing problem in HIV-infected persons. In those who are able to take antiretroviral therapy, the forms of liver disease have changed and their relative importance has increased. This review focuses on liver disease in HIV-infected persons, caused by hepatitis C virus, hepatitis B virus, or treatment of HIV infection.

Tolerance of a short course of nevirapine, associated with 2 nucleoside analogues, in postexposure prophylaxis of HIV

A combination of 2 nucleoside analogues and 1 protease inhibitor is usually recommended in postexposure prophylaxis. Because of the complex treatment schedule and frequent adverse effects, however, this regimen is often not completed. Therefore, since January 2000, we have used nevirapine (NVP), 200 mg/d, for only 4 days in combination with 2 nucleoside analogues for 1 month to improve adherence and completion rates. We present a 2-year retrospective analysis on 120 individuals who received this prophylaxis. Only 2 subjects stopped NVP because of a clinical event, whereas 10 interrupted the nucleoside analogues. We observed 3 (2.8%) of 104 slight alanine aminotransferase (ALT) increases in the first 2 weeks of treatment (grade 1). Three additional (month 1 or 3) ALT augmentations also occurred (also grade 1). No HIV or hepatitis C virus seroconversion occurred during follow-up. Twenty-nine (38.2%) of 76 individuals and 21 (47.7%) of 44 individuals were seen 3 months after nonoccupational and occupational exposure, respectively. We believe that such a short course (4 days) of 200-mg NVP treatment once a day in combination with 2 nucleoside analogues for 1 month is clinically and biologically safe.

Are Specific Antiretrovirals associated with an Increased Risk of Discontinuation due to Toxicities or Patient/Physician Choice in patients with Hepatitis C Virus Coinfection?

Background

Liver damage associated with hepatitis C (HCV) may influence the likelihood of experiencing discontinuation due to toxicities or patient/physician choice (TOXPC) in patients taking combination antiretroviral therapy (cART). Little information to address this concern is available from clinical trials as patients with HCV are often excluded.

Aims

To compare incidence rates of discontinuation due to TOXPC associated with specific antiretrovial drugs in patients with or without HCV.

Patients/methods

A total of 4929 patients from EuroSIDA under follow-up from January 1999 on a specific nucleoside pair (zidovudine/lamivudine, didanosine/stavudine, stavudine/lamivudine, or other) with a third drug (abacavir, nelfinavir, indinavir, nevirapine, efavirenz, lopinavir/ ritonavir or other boosted-protease inhibitor (PI)-containing regimen) and with known HCV serostatus were studied for the incidence of discontinuation of any nucleoside pair or third drug due to TOXPC. Incidence rate ratios were derived from Poisson regression models.

Results

In total 1358 patients had HCV (27.5%). During 12 799 person-years of follow-up there were 2141 discontinuations due to TOXPC for nucleoside pairs and 2501 for third drugs. The incidence of discontinuation due to TOXPC was consistently higher in patients with HCV after stratification by nucleoside pair or third drug. After adjustment for CD4+ count, gender, exposure group, time on HAART, region and treatment regimen, there were few differences in the rate of discontinuation due to TOXPC in those with HCV compared with those without for any nucleoside pairs or third drugs. Similar results were seen when concentrating on discontinuation due to toxicities alone.

Conclusions

Although patients with HCV generally had higher rates of discontinuation due to TOXPC compared with patients without HCV, there was little evidence to suggest that this was associated with any specific nucleoside pair or third drug used as part of cART. Our results do not suggest that any specific component of cART is more poorly tolerated in patients with HCV or that the presence of HCV should influence the choice between antiretrovirals used as part of a cART regimen.

Management and treatment of hepatitis C virus infection in HIV-infected adults: recommendations from the Veterans Affairs Hepatitis C Resource Center Program and National Hepatitis C Program Office

Nearly 40% of human immunodeficiency virus- (HIV-) infected veterans on highly active antiretroviral therapy (HAART) in the United States are coinfected with hepatitis C virus (HCV). With the increased survival due to declining opportunistic infections as a result of HAART, HCV-associated liver disease has become a leading cause of death in HIV-infected individuals. HCV infection has been shown to lead to rapid progression of HCV-related liver disease in HIV infection. Results from recent clinical trials in HIV/HCV-coinfected patients show improved response rates using pegylated formulations of interferon plus ribavirin when compared to standard interferon plus ribavirin. However, the treatment of HCV in HIV/HCV-coinfected patients can be complicated by the hepatotoxic and myelosuppressive effects of HIV therapy and HIV infection itself. Prior to initiating HCV therapy, HIV therapy should be optimized by improving immune suppression and avoiding specific antiretroviral drugs that may cause hepatotoxicity and myelosuppression. In the event of treatment-related neutropenia or anemia during HCV therapy, the use of growth factors should be considered to maximize sustained virologic response to HCV therapy. In HIV/HCV-coinfected patients with end-stage liver disease, liver transplantation is being investigated and shows promise as a potential therapeutic option. With the recent advances in the treatment of HCV in HIV/HCV-coinfected individuals, all HIV/HCV-coinfected patients eligible for HCV treatment should be evaluated for HCV combination therapy with careful consideration of their HIV disease.

Serious Adverse Cutaneous and Hepatic Toxicities Associated With Nevirapine Use by Non???HIV-Infected Individuals

BACKGROUND

Nevirapine is a nonnucleoside reverse transcriptase antiretroviral agent. Among HIV-infected individuals, rare instances (<1%) of serious cutaneous and hepatic toxicity have been reported. Because of its favorable pharmacokinetic profile, non-HIV-infected individuals have received nevirapine-containing postexposure prophylaxis (PEP).

OBJECTIVE

To describe the clinical features of cutaneous and hepatic toxicity that occurred when nevirapine was administered to non-HIV-infected individuals.

METHODS

Reports of nevirapine-associated cutaneous or hepatic toxicity occurring among non-HIV-infected individuals were obtained from the US Food and Drug Administration's adverse event reporting system, the pharmaceutic manufacturer, occupational health programs in Chicago, physicians, and case reports. The Eastern Cooperative Oncology Group (ECOG) scoring system was used to grade toxicity.

RESULTS

Twelve non-HIV-infected individuals developed severe cutaneous toxicity, including 3 with Stevens-Johnson syndrome, after 7 to 12 days of nevirapine-containing PEP regimens. Thirty non-HIV-infected individuals developed hepatotoxicity after 8 to 35 days of single-agent nevirapine (n = 8) or a nevirapine-containing PEP regimen (n = 22). Findings included ECOG grade 3 or 4 hepatotoxicity (n = 14), fevers (n = 11), skin rashes (n = 8), eosinophilia (n = 6), and fulminant hepatic necrosis requiring an orthotopic liver transplant (n = 1). Rates of severe hepatotoxicity (grade 3 or 4) in non-HIV-infected individuals ranged from 10% (4/41) to 62% (5/8). Liver biopsy material from 2 individuals was consistent with a hypersensitivity syndrome.

CONCLUSIONS

Serious hepatic and cutaneous toxicities can occur in non-HIV-infected individuals who receive short-term nevirapine therapy. The rate of severe hepatotoxicity appears to be greater in non-HIV-infected individuals than in HIV-infected persons and may be associated with higher CD4 counts. The use of PEP regimens containing nevirapine should be discouraged.

Acute liver enzyme elevations in HIV-1-infected patients

BACKGROUND

Acute liver enzyme elevations (ALEE) have been associated with a first-line highly active antiretroviral therapy (HAART) and/or viral hepatitis coinfections in HIV-infected patients. By comparison, the frequency and the risk factors of ALEE in untreated patients and in patients treated with several antiretroviral regimens need to be assessed.

PURPOSE

To describe the long-term frequency and the characteristics of ALEE in antiretroviral treated and untreated patients and to define risk factors for ALEE in a retrospective cohort of HIV-1-infected patients.

METHOD

An HIV-infected cohort was retrospectively examined. ALEE was defined as levels of alanine amino transferase and/or alkaline phosphatase rising to at least 2.5 times above baseline values. Hazard ratios (HR) for ALEE were estimated using an extension of the Cox proportional model taking into account recurrent events.

RESULTS

Out of 239 assessable patients, 12 (5%) were coinfected with hepatitis B virus (HBV) and 34 (14.2%) with hepatitis C virus (HCV). The incidence rate of ALEE was 9.9/100 patients-year and the cumulative incidence was 20.9%. HCV genotype 3 tended to give a higher risk of ALEE. Independent factors for developing ALEE in multivariate logistic regression were HBV (HR = 4.0) and HCV (HR = 3.4) coinfections, antiretroviral therapy (HR = 2.6), CDC stage C (HR = 2.5), and high alkaline phosphatase baseline values (HR = 1.7).

CONCLUSION

The occurrence of ALEE is influenced more by the past medical history and the clinical background of the patients than by antiretroviral therapy. These patient-linked variables must be taken into account to avoid unwarranted treatment withdrawal.

Case series of acute hepatitis in a non-selected group of HIV-infected patients on nevirapine-containing antiretroviral treatment

OBJECTIVE

To evaluate the characteristics of patients who developed acute clinical hepatitis in an unselected outpatient population.

METHODS

Patients who started a nevirapine-containing regimen in the period January 1999-February 2001 and presented with clinical symptoms in accordance with increased transaminase values within 12 weeks of initiation of nevirapine were considered possible cases of clinical hepatotoxicity. Patient characteristics, co-medicated drugs, HIV-1 RNA levels and clinical chemistry parameters were collected from outpatient medical records and clinical medical records.

RESULTS

At the defined period, 306 patients started a nevirapine-containing regimen, of whom eight developed an acute hepatitis (2.6%) in a median of 24 days [interquartile range (IQR) 20-25 days]. Transaminases peaked at 28 days (IQR, 27-32 days). Injury pattern was in general mixed-hepatocellular. Withdrawal of the antiretroviral agent led to rapid restoration of transaminase levels and resolution of clinical symptoms. The reason for developing this hepatic reaction was not clear in every case as no specific risk factor(s) covering all patients in this case series could be identified.

CONCLUSIONS

It is very important to monitor closely transaminase levels of all patients starting a nevirapine-containing regimen, including patients with no specific characteristics that put them at risk. The rapid onset of the clinical symptoms pleads for transaminase monitoring at a very early stage (i.e., within 2 weeks of initiation) of the nevirapine-containing regimen.

Antiretroviral-associated liver injury

ART-related hepatotoxicity can manifest in a variety of ways. Although benign, asymptomatic LEEs predominate, liver injury occurring in the context of either hypersensitivity or hyperlactatemia, represents a medical emergency and mandates immediate cessation of ART. Underpinning this broad spectrum of presentations are several, as yet poorly understood, mechanisms of liver damage that reflect contributions by constituents of HAART and host factors. Thus far, the most significant predisposing condition to emerge from clinical studies is chronic viral hepatitis. A more precise understanding, however, of the processes and factors that underlie ART-related hepatotoxicity is critical not only to the management of liver injury from current antiretroviral drugs but also to the design of safer drugs in the future.

Acute hepatic failure and lactate acidosis associated with antiretroviral treatment for HIV

Severe hepatotoxicity is a rare but potentially life-threatening side effect of antiretroviral therapy. In this case report we describe an HIV-positive patient who was admitted to our clinic with evidence of severe acute pancreatitis 18 months after the introduction of antiretroviral treatment, which included stavudine and didanosine. Shortly afterwards, she developed lactate acidosis and acute hepatic failure associated with renal failure. Renal support (hemofiltration) was required for three days. The patient subsequently developed grade III encephalopathy, as well as a large pleural effusion and ascites. Although the reported outcome of patients with liver failure due to antiretroviral treatment is poor, with a high mortality rate, our patient fully recovered after intensive supportive care and cessation of the antiretroviral agents. Liver biopsy revealed microvesicular steatosis and giant mitochondria, which are the typical hallmarks of mitochondrial damage, the presumed mechanism of antiretroviral drug toxicity. More than three years later the patient has an excellent clinical status with a stable HIV infection and no need for antiretroviral treatment. This case report indicates the need for increased awareness of the potential hepatotoxicity of an antiretroviral therapy, as severe side effects may occur more frequently with increasing use of such treatment.

Hepatitis C in the HIV-infected patient

Hepatitis C virus infection is common in people with HIV and represents an increasingly important public health problem. Thus, although there remains a considerable amount of uncertainty about whom to treat and the best way to treat, providers must use available information generated chiefly from patients without HIV to manage HCV infection in coinfected patients. Future efforts should include prospective studies that demonstrate the natural history and optimal management of HIV/HCV-coinfected patients, including the feasibility of liver transplantation.

A cohort study of nevirapine tolerance in clinical practice: French Aquitaine Cohort, 1997-1999

We performed a retrospective study to evaluate, under routine circumstances, the tolerance and immunovirological changes associated with antiretroviral regimens that contain nevirapine in 137 patients (88% were antiretroviral experienced). During a mean follow-up of 11 months, 33% of patients reported side effects attributed to nevirapine, and 21% discontinued treatment because of poor tolerance. Administration of antihistamines or corticosteroids at the initiation of treatment was not protective against adverse events (relative risk, 0.82; 95% confidence interval, 0.49-1.38). The proportion of patients with hepatitis C virus (HCV) and/or hepatitis B virus (HBV) coinfection who had alanine aminotransferase levels of >100 IU/L increased from 19.4% at baseline to 42.9% at month 12 of follow-up (P=.02). We noticed a significant increase of the proportion of patients with total cholesterol levels of >5.5 mM (P=.02). We have shown that there is a high level of discontinuation of nevirapine therapy in clinical practice and that side effects were not prevented by administration of antihistamines or corticosteroids. Coinfection with HCV or HBV increased the risk of hepatotoxicity, which lead to the cautious use of nevirapine for such patients.

Acute liver failure associated with antiretroviral treatment for HIV: a report of six cases

BACKGROUND/AIMS

Severe hepatotoxicity is a rare but potentially fatal side effect of all antiretrovirals. We report a series of six human immunodeficiency virus (HIV)-infected patients admitted with acute liver failure (ALF) over a 25-month period, of whom five died. All had been treated with a range of antiretroviral therapy and only two had had acquired immune deficiency syndrome (AIDS) defining illnesses.

RESULTS

Median duration of antiretroviral therapy was 12.5 months (range 1-23). Median time from the introduction of new antiretroviral therapy to the onset of ALF was 8 weeks (range 2-12). The development of ALF was unrelated to duration of HIV treatment or type of antiretroviral therapy, and was not predicted by close out-patient supervision and monitoring of liver function. Biochemical investigations were variable but revealed a predominantly hepatocellular pattern. Liver biopsy revealed typical features of mitochondrial toxicity in only one case, with confluent hepatocellular necrosis, inflammation and cholestasis seen in the others.

CONCLUSIONS

There is a need to increase awareness of the potential hepatotoxicity of antiretroviral therapy and to develop means of predicting its development. With increasing usage of antiretroviral therapy, severe hepatotoxicity and ALF may arise more frequently, and the outcome is poor despite intensive supportive therapy.

Hepatotoxicity associated with nevirapine or efavirenz-containing antiretroviral therapy: role of hepatitis C and B infections

Hepatologists are frequently asked to evaluate human immunodeficiency virus (HIV)-infected patients with abnormal liver enzymes and to assess the causal role of medications, such as antiretroviral drugs. Recently, the use of HIV-1 specific non-nucleoside reverse transcriptase inhibitors (NNRTIs), including nevirapine (NVP) and efavirenz (EFV), has been associated with severe hepatic injury. We prospectively studied the incidence of severe hepatotoxicity (grade 3 or 4 change in alanine or aspartate transaminase levels) among 568 patients receiving NNRTI-containing antiretroviral therapy, including 312 and 256 patients prescribed EFV and NVP, respectively. Hepatitis C virus (HCV) and hepatitis B virus (HBV) were detected in 43% and 7.7% of patients, respectively. Severe hepatotoxicity was observed in 15.6% of patients prescribed NVP and 8.0% of those prescribed EFV, but only 32% of NVP and 50% of EFV-associated episodes were detected during the first 12-weeks of therapy. The risk was significantly greater among persons with chronic viral hepatitis (69% of cases) and those prescribed concurrent protease inhibitors (PIs) (82% of cases). Nonetheless, 84% of patients with chronic HCV or HBV did not experience severe hepatotoxicity. Severe hepatotoxicity occurs throughout the course of NNRTI therapy and is more common among patients prescribed nevirapine, those coinfected with HCV or HBV, and those coadministered protease inhibitors.

Prednisolone does not prevent hypersensitivity reactions in antiretroviral drug regimens containing abacavir with or without nevirapine

OBJECTIVES

To determine the effect of adjuvant prednisolone use on the development of abacavir (ABC)- and nevirapine (NVP)-associated hypersensitivity reactions (HSR).

METHODS

Randomized open-label study in antiretroviral-naive adult HIV-1 infected patients using a factorial design in which NVP and/or hydroxyurea (HU) and/or prednisolone are added to a regimen of ABC, zidovudine and lamivudine. Prednisolone (40 mg once daily) was added for the first 2 weeks of treatment. As it was difficult to distinguish ABC-associated HSR from NVP-associated HSR, these events were treated as a composite endpoint. The odds ratio (OR) of developing HSR for prednisolone-use was calculated with and without stratification by NVP and/or HU. Logistic regression was performed to identify risk factors for developing HSR.

RESULTS

Of the 229 patients 115 were randomized to prednisolone and 114 to no-prednisolone; 19 (17%) and 11 (10%) patients, respectively, developed HSR. The expected prevention of HSR by prednisolone use was not observed. In fact use of prednisolone showed an increased risk for HSR although this did not reach statistical significance [OR, 1.82; 95% confidence interval (CI), 0.82-4.03]. There was a higher incidence of HSR in the NVP group than in the non-NVP group (20% versus 6%; P = 0.002). An additional risk factor identified in a multivariate logistic model was a high baseline CD4 cell count (OR, 1.26 per 100 x 10(6) cells/l increase; 95% CI, 1.06-1.51).

CONCLUSIONS

The simultaneous start of ABC and NVP in first-line antiretroviral regimens should be avoided because of a high (20%) incidence of HSR. Short-term therapy with prednisolone did not prevent HSR in patients using ABC with or without NVP.

Toxic epidermal necrolysis induced by nevirapine therapy: description of two cases and review of the literature

We describe two cases of toxic epidermal necrolysis developed during an antiretroviral therapy regimen containing nevirapine. It seems likely that the poor adherence to the dose escalation regimen of nevirapine has caused this life-threatening disease. A complete and written information on the scheduled antiretroviral therapy is mandatory, above all for individuals coming from developing countries where language barriers have not yet been successfully overcome.

Hepatotoxicity in HIV-1-infected patients receiving nevirapine-containing antiretroviral therapy

OBJECTIVES

To assess the incidence and risk factors for hepatotoxicity associated with nevirapine.

DESIGN

A prospective cohort study in a teaching and referral hospital involving all consecutive patients who were prescribed a nevirapine-containing antiretroviral regimen between September 1997 and May 2000.

METHOD

Cutaneous and hepatic adverse reactions and clinical hepatitis were assessed. Blood analysis including plasma HIV-1 RNA CD4 cell counts, liver chemistry tests, and serology for hepatitis B and C viruses. Hepatotoxicity was defined as an increase of at least threefold in serum alanine aminotransferase or aspartate aminotransferase levels compared with baseline values.

RESULTS

Of a total of 610 patients, 82 (13.4%) were antiretroviral naive when commencing nevirapine, and 46.2 and 8.9% were coinfected with hepatitis C and B viruses, respectively. Median duration of exposure to nevirapine was 8.7 months (interquartile range 3.4--14.3). Hepatotoxicity developed in 76 (12.5%), an incidence of 13.1/100 person-years. Kaplan--Meier estimated incidence of hepatotoxicity at 3, 6 and 12 months was 3.7, 9.7 and 20.1%, respectively. In seven (1.1%) patients, hepatotoxicity was associated with clinical hepatitis, which was reversible upon discontinuation of therapy. Multivariate analysis identified the duration of prior exposure to antiretroviral drugs, hepatitis C virus, and higher baseline levels of alanine aminotransferase as independent risk factors for hepatotoxicity.

CONCLUSIONS

Hepatotoxicity but not clinical hepatitis was common in HIV-1-infected patients receiving nevirapine-containing regimens and the incidence steadily increased over time. Prolonged exposure to any antiretroviral therapy, coinfection with hepatitis C virus and abnormal baseline levels of alanine aminotransferase identified patients at a higher risk.

Jaundice and hepatocellular damage associated with nevirapine therapy

OBJECTIVE

Nevirapine is a nonnucleoside reverse transcription inhibitor that is used as part of highly active antiretroviral therapeutic combinations. Nevirapine has been associated with a skin rash in 32 to 48% of patients. Recent reports indicate that hepatic toxicity also occurs.

METHODS

We describe four instances of reversible hepatocellular damage associated with the use of nevirapine in patients with HIV infection. Two of the four patients were also coinfected with the hepatitis C virus.

RESULTS

Evidence of malaise, skin rash, and icteric hepatitis with pruritus occurred 4-6 wk after the beginning of nevirapine therapy. No evidence of metabolic acidosis was present in any of our patients. In all cases, liver test results declined to normal or near normal levels, and pruritus disappeared 4-6 wk after discontinuation of the medication. No patient was rechallenged with the drug.

CONCLUSION

Nevirapine can be associated with icteric hepatitis, which appears to be reversible after withdrawal of the drug.