Maternal hepatotoxicity with nevirapine as part of combination antiretroviral therapy in pregnancy

Antiretroviral Options and Treatment Decisions During Pregnancy

The majority of pediatric human immunodeficiency virus (HIV) infections are the result of vertical transmissions that occur during pregnancy, childbirth, and breastfeeding. The treatment of all pregnant persons living with HIV remains a global health initiative. Early and consistent use of antiretroviral therapy throughout pregnancy and childbirth drastically reduces the risk of perinatal transmission of HIV, resulting in fewer children living with the disease worldwide. Given that the maternal HIV viral load is the strongest predictor of perinatal transmission, suppressive antiretroviral treatment during pregnancy is the principal means to eliminate transmission of HIV from mother to child. With the use of combined antiretroviral therapy, typically with dual-nucleoside reverse transcriptase inhibitors plus an integrase strand transfer inhibitor or a ritonavir-boosted protease inhibitor, HIV-infected mothers can now achieve virologic suppression to undetectable levels and yield a perinatal transmission rate of less than 2%. Important considerations of HIV treatment in pregnancy include the safety and efficacy of antiretroviral drugs, altered pregnancy-related pharmacokinetics, potential for birth defects or adverse neonatal outcomes, and individualized delivery planning based on maternal viral load. This practical review article summarizes the options, considerations, and recommendations for antiretroviral treatment in pregnancy to reduce perinatal HIV transmission and optimize health outcomes for mothers and infants worldwide.

Liver injury associated with drug intake during pregnancy

Drug use during pregnancy is not common. Drug-induced liver injury (DILI) is a potential complication that is rare but can adversely affect both the mother and the fetus. Although many drugs can directly cause hepatotoxicity, idiosyncratic liver injury is common in pregnancy. Underreporting of adverse drug reactions, lack of adequate literature regarding drug safety in pregnancy, and the inherent difficulty in diagnosing DILI during pregnancy make the management of this condition challenging. This review attempts to describe the existing literature regarding DILI in pregnancy, which is mainly in the form of case reports; several studies have looked at the safety of antithyroid drugs, antiretroviral drugs, and paracetamol, which have an indication for use in pregnancy; the relevant data from these studies with regard to DILI has been presented. In addition, the review describes the diagnosis of DILI, grading the disease severity, assessment of causality linking the drug to the adverse event, regulatory guidelines for evaluating the potential of drugs to cause liver injury, efforts to ensure better participation of women in clinical trials and studies in pregnant women population in particular, and the challenges involved in generating adequate research evidence. The establishment of DILI registries in various countries is an encouraging development; however, there is a need for promoting active, spontaneous reporting of adverse events during pregnancy to ensure rapid generation of evidence regarding the safety of a drug in pregnant women.

Drug-induced liver injury in pregnancy

Drug intake in pregnant women is common, including prescribed and over-the-counter medications, and herbal medicine and supplements. Drug-induced liver injury (DILI) has become the leading cause of acute liver failure in Western countries, and pregnancy is thought to be a risk factor, but only few anecdotal reports concerning pregnant women are found. These involved antihypertensive, antithyroid, antiretroviral, and antituberculosis medications, and antibiotics. Presentation was usually in the first 20 weeks of gestation following a latency of several weeks, because these drugs were usually prescribed before or in early pregnancy due to their fetal safety. The hepatotoxicity is usually of the idiosyncratic form, and most would resolve spontaneously although occasional liver transplantation and maternal death were reported. The scanty reports could have been related to under-reporting and missed diagnosis due to spontaneous resolution in most cases. DILI should remain one of the differential diagnoses in pregnant women with hepatitis.

Liver Enzyme Elevation in Pregnant Women Receiving Antiretroviral Therapy in the ANRS-French Perinatal Cohort

BACKGROUND

High rates of liver enzyme elevation (LEE) in women receiving antiretroviral treatment (ART) during pregnancy have been reported, but causes remain unclear. We estimated the prevalence and risk factors of LEE in a national prospective multicenter cohort.

METHODS

We studied 5748 pregnant women living with HIV enrolled in the French Perinatal Cohort 2005-2014, treated with ART, with no active hepatitis B or C coinfection. Adjusted hazard ratio (aHR) was estimated using Cox models with ART as time-dependent variable, separately for women on ART at conception and those initiating ART during pregnancy.

RESULTS

LEE (grade ≥ 1) was observed in 16.7%, grade 3-4 in 2%. Among women with LEE, 6.7% had pre-eclampsia, 9.8% intrahepatic cholestasis of pregnancy, and 1.4% other identified medical causes. Most LEEs (82.2%) were unexplained. In women with unexplained LEE, LEE was the reason for hospitalization in 51 (6%) women, cesarean section in 13 (2%), induction of labor in 3 (0.4%), and change in ART regimen in 49 (6%) women. Unexplained LEE was associated with higher risk of preterm births, P < 0.001. Among women on ART at conception, the risk of unexplained LEE was lower with NNRTI-based regimens than with PI-based regimens: aHR = 0.5 (0.3-0.7), with no difference among the PI drugs. Most women initiating ART during pregnancy were on a PI-based regimen (89%). Among them, LEE was less frequent for women on nelfinavir vs. lopinavir/r [aHR = 0.4 (0.2-0.8)].

CONCLUSIONS

Rates of LEE among pregnant women living with HIV are high and impact obstetrical care management. The possible role of PIs needs further investigation.

Inclusion of pregnant women in antiretroviral drug research: what is needed to move forwards?

INTRODUCTION

To adequately ascertain drug safety and efficacy, drug trials need to include participants from all groups likely to receive the medication following approval. Pregnant women, however, are mostly excluded from trials, and women participating are often required to use highly effective contraception and taken off study product (even off study) if they conceive. There is little commercial incentive for including pregnant women in clinical trials, even when preclinical animal and human pharmacokinetic and safety data appear reassuring. With this conservative approach, large numbers of pregnant women are exposed to drug postlicensing with little known about drug safety and efficacy, and little done to systematically monitor outcomes of pregnancy exposure.

DISCUSSION

The article focuses on antiretrovirals for treating and preventing HIV, and presents potential approaches which could extend to other therapeutic areas, to obtaining adequate and timely data to inform use of these drugs in this population. Most importantly the pregnancy risk profile of investigational agents can be systematically stratified from low to high risk, based on guidelines from regulatory bodies. This stratification can determine the progress through preclinical work with animals and non-pregnant women to opportunistic studies among women who become pregnant on a clinical trial or within routine clinical treatment. Stratification can include pregnant women in clinical trials, concurrent with Phase II/III trials in non-pregnant adults, and ultimately to postmarketing surveillance for outcomes in pregnant women and their infants. Each step can be enabled by clear criteria from international and local regulatory bodies on progression through study phases, standardized protocols for collecting relevant data, collaborative data sharing, pregnancy outcomes surveillance systems supported by committed funding for these endeavours.

CONCLUSIONS

A formalized step-wise approach to including pregnant women in antiretroviral drug research should become the new norm. Systematic implementation of this approach would yield more timely and higher quality pregnancy dosing, safety and efficacy data. Through more vigorous action, regulatory bodies could responsibly overcome reluctance to include pregnant women in drug trials. Funders, researchers and programme implementers need to be galvanized to progressively include pregnant women in research - the use of newer, more effective drugs in women is at stake (349).

Assessment of the nevirapine safety signal using data from the national antiretroviral dispensing database: a retrospective study

BACKGROUND

Clinical trials showed a higher risk of skin- and liver- related adverse reactions when NVP-based antiretroviral therapy (ART) was initiated in female and male patients with baseline CD4 cell counts ≥250 and ≥400, respectively. Some studies reported no difference in risk between the high and low CD4 count groups. Consequently, the use of NVP-based ART in all patients with a CD4 cell count <350, was recommended. In 2011, the Pharmacovigilance Centre detected an increase in reports of grade III and IV reactions. The center was required to determine if there was an increase in NVP-related reactions.

METHODS

Automated dispensing records from January 2008 to November 2011 were accessed from the National Antiretroviral Dispensing Database (NDB). Records of patients who were initiated on NVP-based ART were selected, and records showing a replacement of NVP with protease inhibitor (PI) were identified. The proportions of grade III and IV reactions were calculated per quarter, and Odds Ratios (OR) were calculated, with the confidence interval set at 95 % and a p-value of <0.05.

RESULTS

From 2008 to 2011 a total of 84,741 patients were started on ART. Of these 67,794 were initiated on NVP-containing ART. Of these, 211 females and 79 males were substituted from NVP to a PI. The OR for females was 2.4 (95 % confidence interval [CI] 1.8 - 3.1). For males the OR was 2.4 (OR 2.4; 95 % CI 1.4 - 3.8) which occurred nine months after the change observed in the females. The odds of a NVP-to-PI substitution in females compared to males before the launch of Namibia's 2010 ART guidelines was the same as the odds after the publication of the guidelines (before, OR 1.6; 95 % CI 1.1 - 2.5; after, OR 1.6; 95 % CI 1.2 - 2.2).

CONCLUSIONS

There was an increase in substitutions of NVP with a PI following the increase in the CD4 threshold for initiating NVP-based HAART, meaning that there was an increase in grade III and IV reactions associated with NVP. Therefore the NVP-safety signal was confirmed to be a true signal, which contributed to the Ministry's decision to review the use of NVP.

Pregnancy is associated with elevation of liver enzymes in HIV-positive women on antiretroviral therapy

Objective:

The objective of this study is to assess whether pregnancy is associated with an increased risk of liver enzyme elevation (LEE) and severe LEE in HIV-positive women on antiretroviral therapy (ART).

Design:

Two observational studies: the UK Collaborative HIV Cohort (UK CHIC) study and the UK and Ireland National Study of HIV in Pregnancy and Childhood (NSHPC).

Methods:

Combined data from UK CHIC and NSHPC were used to identify factors associated with LEE (grade 1–4) and severe LEE (grade 3–4). Women starting ART in 2000–2012 were included irrespective of pregnancy status. Cox proportional hazards were used to assess fixed and time-dependent covariates including pregnancy status, CD4⁺ cell count, drug regimen and hepatitis B virus/hepatitis C virus (HBV/HCV) coinfection.

Results:

One-quarter (25.7%, 982/3815) of women were pregnant during follow-up, 14.2% (n = 541) when starting ART. The rate of LEE was 14.5/100 person-years in and 6.0/100 person-years outside of pregnancy. The rate of severe LEE was 3.9/100 person-years in and 0.6/100 person-years outside of pregnancy. The risk of LEE and severe LEE was increased during pregnancy [LEE: adjusted hazard ratio (aHR) 1.66 (1.31–2.09); severe LEE: aHR 3.57 (2.30–5.54)], including in secondary analyses excluding 541 women pregnant when starting ART. Other factors associated with LEE and severe LEE included lower CD4⁺ cell count (<250 cells/μl), HBV/HCV coinfection and calendar year.

Conclusion:

Although few women developed severe LEE, this study provides further evidence that pregnancy is associated with an increased risk of LEE and severe LEE, reinforcing the need for regular monitoring of liver biomarkers during pregnancy.

Preventing tuberculosis among HIV-infected pregnant women in Lesotho: the case for rolling out active case finding and isoniazid preventive therapy

BACKGROUND

The Lesotho Ministry of Health issued guidelines on active case finding (ACF) for tuberculosis (TB) and isoniazid preventive therapy (IPT) in April 2011. ACF has been recommended in maternal and child health (MCH) settings globally, however, the feasibility of implementing IPT within MCH in countries with high concurrent HIV and TB epidemics is unknown.

DESIGN/METHODS

The study evaluated the implementation of ACF and IPT guidelines in MCH settings in 2 health facilities in Lesotho. This descriptive prospective study analyzed data collected during routine services. Categorical data and continuous variables were summarized using descriptive statistics. The χ test or Wilcoxon rank-sum test was used to ascertain significant associations between categorical and continuous variables, respectively.

RESULTS

Data from 160 HIV-positive and 640 HIV-negative women were reviewed. Within this study population, 99.8% of women were screened for TB, and 11.4% HIV-positive women compared with 2.3% HIV-negative women were reported to have symptoms of TB (P < 0.001). IPT was initiated in 124/158 (78.5%) HIV-positive pregnant women, 64.5% women completed a 6-month IPT regimen, 2 (1.6%) died of causes unrelated to IPT/TB, and 31.5% were lost to follow-up. Predictors of IPT initiation among HIV-positive women included gestational age at the first antenatal visit (unadjusted odds ratio, -0.93; 95% confidence interval: -0.88 to 0.98), and receipt of antiretroviral therapy for treatment rather than for prevention of mother-to-child transmission prophylaxis only (odds ratio, 4.59; 95% confidence interval: 1.32 to 15.93).

CONCLUSIONS

Implementation of ACF and IPT is feasible within the MCH setting. Uptake of IPT during pregnancy among HIV-positive women was high, but with a high rate of loss to follow-up.

Adverse drug reactions associated with antiretroviral therapy during pregnancy

INTRODUCTION

Antiretroviral (ARV) drug use during pregnancy significantly reduces mother-to-child HIV transmission, delays disease progression in the women and reduces the risk of HIV transmission to HIV-serodiscordant partners. Pregnant women are susceptible to the same adverse reactions to ARVs as nonpregnant adults as well as to specific pregnancy-related reactions. In addition, we should consider adverse pregnancy outcomes and adverse reactions in children exposed to ARVs during intrauterine life. However, studies designed to assess the safety of ARV in pregnant women are rare, usually with few participants and short follow-up periods.

AREAS COVERED

In this review, we discuss studies reporting adverse reactions to ARV drugs, including maternal toxicity, adverse pregnancy outcomes and the consequences of exposure to ARV in infants. We included results of observational studies, both prospective and retrospective, as well as randomized clinical trials, systematic reviews and meta-analyses.

EXPERT OPINION

The benefits of ARV use during pregnancy outweigh the risks of adverse reactions identified to date. More studies are needed to assess the adverse effects in the medium- and long term in children exposed to ARVs during pregnancy, as well as pregnant women using lifelong antiretroviral therapy and more recently available drugs.

Incidence of antiretroviral adverse drug reactions in pregnant women in two referral centers for HIV prevention of mother-to-child-transmission care and research in Rio de Janeiro, Brazil

Mother-to-child transmission (MTCT) of human immunodeficiency virus (HIV) infection remains an important cause of new HIV infections worldwide, especially in low and middle-resource limited countries. Safety data from studies involving pregnant women and prenatal antiretroviral (ARV) exposure are still needed once these studies are often small and with a limited duration to assess adverse drug reactions (ADR). The aim of this study was to estimate the incidence of ADR related to the use of antiretroviral therapy (ART) in pregnant women in two referral centers in Rio de Janeiro State. A prospective study was carried out from February 2005 to May 2006. Women were classified according to their ART status during pregnancy diagnosis: ARV-experienced (ARTexp) or ARV-naïve (ARTn). Two hundred fourteen HIV-infected pregnant women were included: 36 ARTexp and 178 ARTn. ARTexp women have not experienced ADR. Among ARTn, 20.2% presented ADR. Incidence rate of ADR was 70.8 per 1000 person-months and the most common ADRs observed were: gastrointestinal (belly or abdominal cramps, diarrhea, nausea and vomit) in 16.3%, cutaneous (pruritus and rash) in 6.2%, anemia (2.2%) and hepatitis (1.7%). The frequency of obstetrical complications, pre-term delivery, low birth weight and birth abnormalities was low in this population. ADRs ranged from mild to moderate intensity, none of them being potentially fatal. Only in a few cases it was necessary to discontinue ART. In conclusion, the high effectiveness of ARV for HIV prevention of MTCT (PMTCT) overcomes the risk of ADR.

The interaction of CD4 T-cell count and nevirapine hepatotoxicity in China: a change in national treatment guidelines may be warranted

OBJECTIVES

Nevirapine (NVP), a still widely used nonnucleoside reverse transcriptase inhibitor, can cause severe hepatotoxicity. Previous studies suggest that CD4 cell counts more than 250 cells per microliter in women and more than 400 cells per microliter in men are risk factors for NVP-related hepatotoxicity. These studies have informed Chinese national treatment guidelines. We evaluate whether current Chinese guidelines for NVP use are appropriate.

METHODS

Longitudinal data were pooled from 2 clinical trials between 2005 and 2009 across mainland China. Five hundred sixty-six antiretroviral therapy-naive Chinese patients were given NVP-containing antiretroviral therapy for 24 weeks. Hepatotoxicity was defined as alanine aminotransferase, aspartate transaminase, or total bilirubin level greater than 1.25 times the upper limit of normal range. Severe hepatotoxicity was defined as greater than 5 times the upper limit of normal range.

RESULTS

One hundred ninety-seven (36.1%) patients developed hepatotoxicity during treatment, including 42 (7.7%) patients with severe hepatotoxicity. CD4 cell count more than 250 cells per microliter was an independent predictor for hepatotoxicity both in men [relative risk = 1.22 (95% confidence interval: 1.04 to 1.44)] and in women [relative risk = 1.72 (95% confidence interval: 1.20 to 2.46)]. Severe hepatotoxicity was also more common among all persons with CD4 >250 cells per microliter.

CONCLUSIONS

Hepatotoxicity was a common adverse effect of NVP among men and women with CD4 >250 cells per microliter. Chinese treatment guidelines should be considered to reflect this risk.

Safety of protease inhibitors in HIV-infected pregnant women

The dire conditions of the human immunodeficiency virus/acquired immune deficiency syndrome epidemic and the immense benefits of antiretroviral prophylaxis in prevention of mother-to-child transmission far outweigh the potential for adverse effects and undeniably justify the rapid and widespread use of this therapy, despite incomplete safety data. Highly active antiretroviral therapy has now become standard care, and more than half the validated regimens include protease inhibitors. This paper reviews current knowledge of the safety of these drugs during pregnancy, in terms of maternal and fetal outcomes. Transfer of protease inhibitors across the placenta is known to be minimal, and current data about birth defects and fetal malignancies are reassuring. Maternal liver function and glucose metabolism should be monitored in women treated with protease inhibitor-based regimens, but concerns about the development of maternal resistance, should treatment be discontinued, have been shown to be groundless. Neonates should be screened for hematologic abnormalities, although these are rarely severe or permanent and are not usually related to the protease inhibitor component of the antiretroviral combination. Current findings concerning pre-eclampsia and growth restriction are discordant, and further research is needed to address the question of placental vascular complications. The increased risk of preterm birth attributed to protease inhibitors should be interpreted with caution considering the discrepant results and the multitude of confounding factors often overlooked. Although data are thus far reassuring, further research is needed to shed light on unresolved controversies about the safety of protease inhibitors during pregnancy.

Adverse events associated with nevirapine use in pregnancy: a systematic review and meta-analysis

INTRODUCTION

The risk of adverse drug events associated with nevirapine (NVP) is suggested to be greater in pregnant women. We conducted a systematic review and meta-analysis of severe adverse events in HIV-positive women who initiated NVP while pregnant.

METHODS

We searched six databases for studies reporting adverse events among HIV-positive pregnant women who had received NVP-based antiretroviral therapy for at least 7 days. Data were pooled by the fixed-effects method.

RESULTS

Twenty studies (3582 pregnant women) from 14 countries were included in the final review. The pooled proportion of patients experiencing a severe hepatotoxic event was 3.2% [95% confidence interval (CI) 2.1-4.3%], severe rash was experienced by 3.3% of patients (95% CI 2.1-4.5%) and 6.1% (95% CI 3.9-8.3%) of patients discontinued NVP due to an adverse event. These results were comparable to frequencies observed in the general adult patient population, and to frequencies reported in non-pregnant women within the same cohort. For pregnant women with a CD4 cell count above 250 cells/μl there was a non-significant tendency towards an increased likelihood of severe cutaneous adverse events (OR 1.4, 95% CI 0.8-2.4) and severe hepatotoxic events (OR 1.5, 95%CI 0.9-2.3) and consequently an increased risk of toxicity-driven regimen substitution (OR 1.7, 95% CI 1.1-2.6).

DISCUSSION

These results suggest that the frequency of adverse events associated with NVP use in pregnant women, although high, is no higher than reported for NVP in the general adult population. Pregnant women with a high CD4 cell count may be at increased risk of adverse events, but evidence supporting this association is weak.

Tuberculosis in pregnant and postpartum women: epidemiology, management, and research gaps

Tuberculosis is most common during a woman's reproductive years and is a major cause of maternal-child mortality. National guidelines for screening and management vary widely owing to insufficient data. In this article, we review the available data on (1) the global burden of tuberculosis in women of reproductive age; (2) how pregnancy and the postpartum period affect the course of tuberculosis; (3) how to screen and diagnose pregnant and postpartum women for active and latent tuberculosis; (4) the management of active and latent tuberculosis in pregnancy and the postpartum period, including the safety of tuberculosis medications; and (5) infant outcomes. We also include data on HIV/tuberculosis coinfection and drug-resistant tuberculosis. Finally, we highlight research gaps in tuberculosis in pregnant and postpartum women.

Hcv coinfection, an important risk factor for hepatotoxicity in pregnant women starting antiretroviral therapy

OBJECTIVES

This retrospective cohort study evaluated the risk of hepatotoxicity in HIV-1 positive pregnant and non-pregnant women starting combined ART.

METHODS

Data were used from the ATHENA observational cohort. The study population consisted of HIV-1 infected, therapy naïve, pregnant and non-pregnant women, followed between January 1997 and February 2008. Demographic, treatment and pregnancy related data were collected. Risk of hepatotoxicity was determined using univariate and multivariate logistic regression. Analyses were adjusted for age, region of origin, baseline HIV-RNA levels and CD4 cell counts, cART regimen and hepatitis B and C coinfection. ALT and AST values of more than 5 times ULN were considered as hepatotoxicity.

RESULTS

Four-hundred and twenty-five pregnant and 1121 non-pregnant women were included. Independent risk factors of hepatotoxicity in all women were the presence of detectable HCV RNA (OR 5.48, 95% CI 2.25-13.38, p<0.001) and NVP use (OR 2.63, 95% CI 1.54-4.55, p<0.001). Stratified for pregnancy, the adjusted risk of hepatotoxicity was significantly associated with HCV coinfection only during pregnancy (OR 23.53, 95% CI 4.69-118.01, p<0.001). NVP use is related to hepatotoxicity in pregnant (OR 5.26, 95% CI 1.61-16.67, p<0.005) as well as in non-pregnant women (OR 2.13, 95% CI 1.11-4.00, p=0.02).

CONCLUSION

HCV coinfection and NVP use are associated with a higher risk of cART induced hepatotoxicity in pregnant women.

Nevirapine-associated hepatotoxicity and rash among HIV-infected pregnant women in Kenya

BACKGROUND

Few studies have evaluated the risk of nevirapine (NVP)-associated hepatotoxicity among HIV-infected pregnant women with a CD4 count ≥250 cells/mm(3).

METHODS

We enrolled HIV-infected pregnant Kenyan women who initiated triple antiretroviral therapy (ART) at 34 weeks gestation. We compared the rates of severe hepatotoxicity (grades 3-4 hepatotoxicity) and rash-associated hepatotoxicity (rash with ≥grade 2 hepatotoxicity) with NVP and nelfinavir (NFV), respectively.

RESULTS

We initiated triple ART in 522 pregnant women; severe hepatotoxicity and rash-associated hepatotoxicity occurred in 14 (3%) and 9 (2%) women, respectively. Women who initiated NVP had higher rates of severe hepatotoxicity (5% vs 1%; P = .03) and rash-associated hepatotoxicity (4% vs 0%; P = .003) when compared with NFV. Among women who initiated NVP (n = 254), a baseline CD4 count ≥250 cells/mm(3) was not associated with severe hepatotoxicity (5% vs 3%; P = .52) or rash-associated hepatotoxicity (4% vs 3%; P = .69).

CONCLUSION

Nevirapine use but not CD4 count ≥250 cells/mm(3) was associated with hepatotoxicity.

Safety of single-dose nevirapine for prevention of vertical transmission of human immunodeficiency virus infection

Introduction:

Nevirapine administered as a single dose each to the mother and child within 72 h after birth is used to prevent vertical transmission of human immunodeficiency virus (HIV) under the prevention of parent to child transmission of HIV program (PPTCT). The efficacy of nevirapine in this regard has been proved beyond doubt, but there are unresolved questions about its safety. Hence, the primary objective of this study was to evaluate the safety of this regime.

Materials and Methods:

HIV-positive pregnant women who consented to participate in the study received a single oral dose of 200 mg nevirapine at the onset of labor followed by administration of 2 mg/kg of nevirapine syrup to the newborn within 72 h of birth. Both mother and child were followed up for 1 week postpartum to note the occurrence of any adverse reactions.

Results:

The mother and child followed up for 1 week postpartum did not show any serious adverse reactions in the present study. Mothers reported adverse reactions like nausea, vomiting, and headache which were self-limiting and did not require any intervention.

Conclusion:

The present study substantiates the safety of nevirapine.

Lopinavir: the old champion

Lopinavir/ritonavir approval for use in antiretroviral treatment 10 years ago was very important for the recognition of boosted protease inhibitor (PI)-based therapy as an attractive option for first-line therapy. Being coformulated with ritonavir and having less toxicity than former PIs it allowed for effective and durable virologic suppression with less impact on quality of life. It soon became the standard of care for salvage therapy in its class. Since then, however, its central role has been challenged by new PIs with a more favorable impact on lipid profile, better gastrointestinal tolerability or that are more active in the setting of multidrug resistance. This article summarizes the main clinical studies with lopinavir and discusses its particular characteristics as well as its possible current role in antiretroviral therapy.

Nevirapine-associated hepatotoxicity was not predicted by CD4 count ≥250 cells/μL among women in Zambia, Thailand and Kenya

OBJECTIVE

The aim of the study was to determine risk factors for developing severe hepatotoxicity (grade 3 or 4 hepatotoxicity) and rash-associated hepatotoxicity (rash with ≥ grade 2 hepatotoxicity) among women initiating nevirapine-based antiretroviral therapy (ART).

METHODS

The Non-Nucleoside Reverse Transcriptase Inhibitor Response Study was a prospective cohort study carried out in Zambia, Thailand and Kenya. Between May 2005 and January 2007, we enrolled antiretroviral-naïve HIV-infected women initiating nevirapine-based ART. At enrollment and at weeks 2, 4, 8, 16 and 24, participants had serum alanine transferase (ALT) and aspartate transaminase (AST) measured and were evaluated clinically for hepatitis and rash.

RESULTS

Nevirapine-based ART was initiated in 820 women and baseline ALT or AST results were abnormal (≥ grade 1) in 113 (14%) women. After initiating nevirapine-based ART, severe hepatotoxicity occurred in 41 (5%) women and rash-associated hepatotoxicity occurred in 27 (3%) women. In a multivariate logistic regression model, severe hepatotoxicity and rash-associated hepatotoxicity were both associated with baseline abnormal (≥ grade 1) ALT or AST results, but not with a baseline CD4 cell count ≥250 cells/μL. Three participants (0.4%) died with symptoms suggestive of fatal hepatotoxicity; all three women had baseline CD4 count <100 cells/μL and were receiving anti-tuberculosis therapy.

CONCLUSION

Among women taking nevirapine-based ART, severe hepatotoxicity and rash-associated hepatotoxicity were predicted by abnormal baseline ALT or AST results, but not by a CD4 count ≥250 cells/μL. In resource-limited settings where transaminase testing is available, testing should focus on early time-points and on women with abnormal baseline ALT or AST results.

Nevirapine-associated toxicity in clinical practice in Buenos Aires, Argentina

OBJECTIVES

to determine the incidence and risk factors for nevirapine (NVP)-associated toxicity in a cohort of HIV-infected people in Buenos Aires, Argentina.

DESIGN

retrospective study.

METHODS

HIV-infected adults who received NVP-based highly active antiretroviral therapy (HAART) at least for 2 weeks between May 1997 and March 2008 were included in this study. We analyzed patients' age, gender, HIV transmission route, HIV disease stage, pregnancy, alcohol intake, adverse events, coinfection with hepatitis B or C virus, time until toxicity, and withdrawal rates.

RESULTS

a total of 1110 patients (631 men) were included. Rash was the most frequently observed adverse event; it was more frequent in women. The incidence of severe rash and hepatotoxicity was similar in women and men. Female sex was the only variable significantly associated with mild-to-moderate rash. High CD4 count, pregnancy, and chronic hepatitis were not associated with NVP-related toxicity. An undetectable viral load at the time of starting NVP treatment resulted in a lower risk of NVP-related rash.

Antiretroviral pharmacology: special issues regarding pregnant women and neonates

Antiretrovirals may be used in pregnant women infected with the HIV and their newborns both for treatment of maternal HIV disease and for prevention of mother-to-child transmission of HIV. More than 25 antiretroviral agents in 5 classes have been approved, with new drugs and classes in development. This article reviews current knowledge of the pharmacology of these drugs during pregnancy and in the newborn period, highlighting those pharmacologic issues critical to the safe and effective use of antiretrovirals in these populations.

Adverse events in a cohort of HIV infected pregnant and non-pregnant women treated with nevirapine versus non-nevirapine antiretroviral medication

Background

Predictors of adverse events (AE) associated with nevirapine use are needed to better understand reports of severe rash or liver enzyme elevation (LEE) in HIV+ women.

Methodology

AE rates following ART initiation were retrospectively assessed in a multi-site cohort of 612 women. Predictors of onset of rash or LEE were determined using univariate and multivariate analyses.

Principal Findings

Of 612 subjects, 152 (24.8%) initiated NVP-based regimens with 86 (56.6%) pregnant; 460 (75.2%) initiated non-NVP regimens with 67 (14.6%) pregnant.

LEE

No significant difference was found between regimens in the development of new grade ≥2 LEE (p = 0.885). Multivariate logistic regression demonstrated an increased likelihood of LEE with HCV co-infection (OR 2.502, 95% CI: 1.04 to 6, p = 0.040); pregnancy, NVP-based regimen, and baseline CD4 >250 cells/mm³ were not associated with this toxicity.

Rash

NVP initiation was associated with rash after controlling for CD4 and pregnancy (OR 2.78; 95%CI: 1.14–6.76), as was baseline CD4 >250 cells/mm³ when controlling for pregnancy and type of regimen (OR 2.68; 95% CI: 1.19–6.02 p = 0.017).

Conclusions

CD4 at initiation of therapy was a predictor of rash but not LEE with NVP use in HIV+ women. Pregnancy was not an independent risk factor for the development of AEs assessed. The findings from this study have significant implications for women of child-bearing age initiating NVP-based ART particularly in resource limited settings. This study sheds more confidence on the lack of LEE risk and the need to monitor rash with the use of this medication.

Incidence and risk factors of severe adverse events with nevirapine-based antiretroviral therapy in HIV-infected women. MTCT-Plus program, Abidjan, Côte d'Ivoire

Background

In resource-limited settings where nevirapine-containing regimen is the preferred regimen in women, data on severe adverse events (SAEs) according to CD4 cell count are limited. We estimated the incidence of SAEs according to CD4 cell count and identify their risk factors in nevirapine-treated women.

Methods

All HIV-infected women who initiated nevirapine-containing regimen in the MTCT-Plus operational program in Abidjan, Côte d'Ivoire, were eligible for this study. Laboratory and clinical (rash) SAEs were classified as grade 3 and 4. Cox models were used to identify factors associated with the occurrence of SAEs.

Results

From August 2003 to October 2006, 290 women initiated a nevirapine-containing regimen at a median CD4 cell count of 186 cells/mm³ (IQR 124-266). During a median follow-up on treatment of 25 months, the incidence of all SAEs was 19.5/100 patient-years. The 24-month probability of occurrence of hepatotoxicity or rash was not different between women with a CD4 cell count >250 cells/mm³ and women with a CD4 cell count ≤250 cells/mm³ (8.3% vs. 9.9%, Log-rank test: p = 0.75). In a multivariate proportional hazard model, neither CD4 cell count >250 cells/mm³ at treatment initiation nor initiation NVP-based regimen initiated during pregnancy were associated with the occurrence of SAEs.

Conclusion

CD4 cell count >250 cells/mm³ was not associated with a higher risk of severe hepatotoxicity and/or rash, as well as initiation of ART during pregnancy. Pharmacovogilance data as well as meta-analysis on women receiving NVP in these settings are needed for better information about NVP toxicity.

Lack of increased hepatotoxicity in HIV-infected pregnant women receiving nevirapine compared with other antiretrovirals

OBJECTIVE

To estimate whether HIV-infected pregnant women were at an increased risk of hepatotoxicity when taking nevirapine (NVP)-containing regimens compared with HIV-infected pregnant women taking antiretroviral therapy (ART) not containing NVP.

METHODS

This analysis included HIV-infected pregnant women on ART from two multicenter, prospective cohorts: the Women and Infants Transmission Study and the International Maternal Pediatric Adolescent AIDS Clinical Trials protocol P1025. Multivariate Cox proportional hazards regression models were used to investigate the association between NVP use and hepatotoxicity. NVP use was dichotomized as use or no use and further categorized according to ART exposure history. We investigated two outcomes: any liver enzyme elevation (LEE) (grade 1-4) and severe LEE (grade 3-4).

RESULTS

A total of 1229 women with ART use during pregnancy were studied, 218 (17.7%) of whom received NVP. Among the women receiving NVP, 137 (62.8%) were NVP naive. Twenty-nine women (13.3%) who received NVP developed any LEE and one (0.5%) developed severe LEE. Of the 1011 women on non-NVP regimens, 145 (14.3%) developed any LEE and 14 (1.4%) developed severe LEE. There were no maternal deaths. In univariate models, LEE was not significantly associated with CD4 cell count above 250 cells/mul or NVP use. In adjusted multivariate models, no significant increased risk of LEE (any or severe) in women taking NVP was detected as compared to those taking other ART regardless of prior exposure history.

CONCLUSION

We did not observe an increased risk of hepatotoxicity among HIV-infected pregnant women on NVP versus other ART, including women who were ART naive.

Antiretroviral therapy-induced liver alterations

PURPOSE OF REVIEW

Antiretroviral drugs are associated with hepatotoxicity. Progress in our knowledge on the prevalence, contributory factors and mechanisms is reviewed.

RECENT FINDINGS

Liver toxicity is highly prevalent and a major cause of hospitalization among HIV-infected individuals. Liver steatosis is probably more frequent in the setting of hepatitis C virus coinfection but is also seen in noncoinfected patients. Among the individual drugs, severe liver toxicity is more strongly associated with nevirapine, and the mitochondrial toxicity of some nucleoside analogues. Mitochondrial toxicity can also induce or contribute to steatohepatitis, with dietary uridine supplementation as a possible strategy of prevention. Atazanavir inhibits UDP-glucuronosyltransferase, which in Gilberts' syndrome has been associated with breast cancer. A UDP-glucuronosyltransferase gene promoter variant predisposes to hyperbilirubinemia. Tipranavir induces elevated transaminases more frequently than boosted comparator protease inhibitors. CCR5 inhibitors may predispose to hepatotoxic events by causing an imbalance in the cytokine response.

SUMMARY

Hepatotoxicity is associated with all classes of antiretroviral agents and continues to contribute to hospitalization.

Increased risk of hepatotoxicity in HIV-infected pregnant women receiving antiretroviral therapy independent of nevirapine exposure

OBJECTIVE

To estimate whether the association between nevirapine (NVP) and hepatotoxicity differs according to pregnancy status in HIV-infected women.

METHODS

The present analysis included HIV-infected pregnant women on antiretroviral therapy (ART) from two multicenter, prospective cohorts - the Women and Infants Transmission Study and the International Maternal Pediatric Adolescent AIDS Clinical Trials protocol P1025 - and HIV-infected nonpregnant women from one multicenter, prospective cohort - the Women's Interagency HIV Study. Using multivariate Cox proportional hazards regression, the interaction between NVP and pregnancy status in terms of hepatotoxicity was investigated. NVP use was dichotomized as use or no use and was further categorized according to ART exposure history. We investigated two outcomes: any liver enzyme elevation (LEE; grade 1-4) and severe LEE (grade 3-4).

RESULTS

Data on 2050 HIV-infected women taking ART were included: 1229 (60.0%) pregnant and 821 (40.0%) nonpregnant. Among the pregnant women, 174 (14.2%) developed any LEE and 15 (1.2%) developed severe LEE as compared with 75 (9.1%) and 5 (0.6%), respectively, of the nonpregnant women. In multivariate adjusted models, NVP was not significantly associated with risk of LEE, regardless of pregnancy status; however, pregnancy was associated with an increased risk of any LEE (relative risk 4.7, confidence interval = 3.4-6.5) and severe LEE (relative risk 3.8, confidence interval = 1.3-11.1). The association of pregnancy and LEE was seen, regardless of prior ART and NVP exposure history.

CONCLUSION

No significant association between NVP and LEE was observed, regardless of pregnancy status, but pregnancy was significantly associated with increased hepatotoxocity in HIV-infected women.

Advances and failures in preventing perinatal human immunodeficiency virus infection

An estimated 2.5 million children are currently living with HIV, the vast majority as a result of mother-to-child transmission. Prevention of perinatal HIV infection has been immensely successful in developed countries. A comprehensive package of services, including maternal and infant antiretroviral therapy, elective cesarean section, and avoidance of breast-feeding, has resulted in transmission rates of less than 2%. However, in developing countries, access to such services is often not available, as demonstrated by the fact that the vast majority of children with HIV live in Africa. Over the past few years, many developing nations have made great strides in improving access to much-needed services. Notably, in eastern and southern Africa, the regions most affected by HIV, mother-to-child-transmission coverage rates for HIV-positive women increased from 11% in 2004 to 31% in 2006. These successes are deserving of recognition, while not losing sight of the fact that much remains to be done; currently, an estimated 75% of pregnant women worldwide have an unmet need for antiretroviral therapy. Further work is needed to determine the optimal strategy for reducing perinatal transmission among women in resource-poor settings, with a particular need for reduction of transmission via breast-feeding.

Adverse Effects of Antiretrovirals in HIV-Infected Pregnant Women

Background

Current guidelines for the use of antiretroviral (ARV) therapy during pregnancy recommend that women be offered treatment with combination ARV therapy used in nonpregnant HIV-infected individuals. It is unclear whether the risk of ARV-related adverse drug reactions (ADRs) is increased during pregnancy.

Objective

To evaluate the frequency and severity of ADRs likely caused by ARV therapy in pregnant women who are HIV-positive.

Methods

A retrospective analysis of HIV-infected women who received ARV therapy during pregnancy and delivered between January 1997 and February 2006 was conducted. Incidence of maternal ADRs was determined through evaluation of laboratory findings, documented physical examinations, and patient self-reports. An AIDS Clinical Trials Group severity grading scale was applied to the ADRs. Cause-effect relationship was adjudicated based on the Naranjo probability scale and, if causality was found, that information was included.

Results

There were 103 women who accounted for 133 pregnancies that resulted in deliveries. Of the 111 pregnancies in which treatment was received, regimens included 26 nucleoside reverse transcriptase inhibitor monotherapy, 40 nonnucleoside reverse transcriptase inhibitor (NNRTI)–based, 44 protease inhibitor (PI)–based, and 1 PI/NNRTI combination therapy. Ninety-eight ADRs were documented in 49 pregnancies. The most common ADRs were gastrointestinal (n = 48), followed by central nervous system symptoms (n = 15), anemia (n = 15), elevated liver/pancreatic enzyme levels (n = 11), and cutaneous reactions (n = 8). Severe ADRs included elevations in liver/pancreatic enzymes (n = 3), nausea and vomiting (n = 3), and anemia (n = 2). Seven women required a change in therapy due to an ADR.

Conclusions

Approximately 7 ADRs were reported for every 10 pregnancies in this cohort. Most ADRs were mild to moderate. Short exposure times in most women (second and third trimester) may have accounted for the lack of long-term toxicities. Although ADRs did not pose a major barrier to use of ARVs in pregnancy, close monitoring of pregnant women receiving ARV therapy continues to be warranted.

Tenofovir disoproxil fumarate in pregnancy and prevention of mother-to-child transmission of HIV-1: is it time to move on from zidovudine?

OBJECTIVES

Zidovudine (ZDV) has been the cornerstone of antiretroviral (ARV) therapy for pregnant women infected with HIV-1 in the prevention of mother-to-child transmission (MTCT) and remains the only licensed ARV for use in pregnancy. We explored the current and future roles of tenofovir disoproxil fumarate (TDF) in the prevention of MTCT of HIV-1.

METHODS

We reviewed the published literature by conducting database searches of in vitro, animal and clinical studies, reported in journals and at conferences, using the search terms Tenofovir/gs4331/viread, pregnant/pregnancy, lactate, lactation, natal, reproduce/reproduction, placenta/placental, malformation, and teratogenicity/teratogenic.

RESULTS

In a macaque model, perinatal exposure to very high dose tenofovir resulted in bone toxicity in some offspring. However, perinatal use of TDF, both single dose and as part of highly active antiretroviral therapy in women, has been well tolerated in the short term by mothers and their infants. Further, the addition of single-dose TDF to single-dose nevirapine (SD-NVP) during delivery following maternal ZDV use during pregnancy significantly reduces the frequency of nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance.

CONCLUSIONS

The addition of TDF to SD-NVP reduces NNRTI resistance. The role of TDF in this setting and during pregnancy for reducing rates of MTCT requires investigation. While short-term toxicity data are encouraging, long-term follow-up of exposed mothers and infants is required.

Antiretroviral treatment during pregnancy

OBJECTIVE

Virologic failure of HIV-positive patients is of special concern during pregnancy. We compared virologic failure and the frequency of treatment changes in pregnant and non-pregnant women of the Swiss HIV Cohort Study.

METHODS

Using data on 372 pregnancies in 324 women we describe antiretroviral therapy during pregnancy. Pregnant women on HAART at conception (n = 131) were matched to 228 non-pregnant women (interindividual comparison) and to a time period of equal length before and after pregnancy (intraindividual comparison). Women starting HAART during pregnancy (n = 145) were compared with 578 non-pregnant women starting HAART.

FINDINGS

The median age at conception was 31 years, 16% (n = 50) were infected through injecting drug use and the median CD4 cell count was 489 cells/microl. In the majority of pregnancies (n = 220, 59%), women had started ART before conception. When ART was started during pregnancy (n = 145, 39%), it was mainly during the second trimester (n = 100, 69%). Two thirds (n = 26) of 35 women starting in the third trimester were diagnosed with HIV during pregnancy. The risk of virologic failure tended to be lower in pregnant than in non-pregnant women [adjusted odds ratio 0.52 (95% confidence interval 0.25-1.09, P = 0.08)], but was similar in the intraindividual comparison (adjusted odds ratio 1.04, 95% confidence interval 0.48-2.28). Women starting HAART during pregnancy changed the treatment less often than non-pregnant women.

CONCLUSION

Despite the physiological changes occurring during pregnancy, HIV infected pregnant women are not at higher risk of virologic failure.

Pharmacokinetics, Safety and Efficacy of Saquinavir/ Ritonavir 1,000/100 Mg Twice Daily as HIV Type-1 Therapy and Transmission Prophylaxis in Pregnancy

Background

A saquinavir/ritonavir-containing regimen is one option for the prevention of mother-to-child transmission of HIV during pregnancy. We evaluated the pharmaco-kinetics, efficacy and safety of saquinavir/ritonavir 1,000/100 mg twice daily plus nucleos(t)ide reverse transcriptase inhibitors in 13 women during late pregnancy and compared the results to those of 15 non-pregnant women.

Methods

Protease inhibitor plasma concentration profiles were assessed at 12 h using a standardized therapeutic drug monitoring procedure and measured by LC-MS/MS. Minimum and maximum concentrations (Cmin and Cmax), area under the plasma concentration–time curve (AUC0–12 h), and total clearance (CL total) were compared between the groups and correlated to demographic, physiological and clinical cofactors. Antiviral and immunological efficacy and safety were investigated.

Results

The geometric means (90% confidence interval [CI]) for saquinavir Cmin, Cmax and AUC0–12 h of pregnant versus non-pregnant women were 572 (437–717) versus 765 (485–1,052, P=0.064) ng/ml, 2,168 (1,594–2,807) versus 3,344 (2,429–4,350; P=0.045) ng/ml and 15,512 (11,657–19,943) versus 24,027 (17,454–31,548, P=0.029) ng•h/ml. The geometric means (90% CI) for ritonavir Cmin, Cmax and AUC0–12 h were 190 (148–234) versus 310 (240–381, P=0.011) ng/ml, 781 (580–999) versus 1,552 (1,127–2,007, P=0.004) ng/ml and 5,576 (4,303–7,006) versus 10,528 (8,131–13,177, P=0.003) ng•h/ml. Age, weight, saquinavir dose per weight and body mass index differed significantly; saquinavir Cmin and AUC0–12 h were correlated with ritonavir Cmin and saquinavir dose per weight. After a mean of 11 weeks treatment, 12 of 13 pregnant women had a viral load <400 copies/ml, which was similar to the results of non-pregnant women.

Conclusions

Although saquinavir plasma concentrations were significantly lower in pregnant women compared with non-pregnant women, all pregnant women displayed a saquinavir AUC0–12 h>10,000 ng•h/ml, 92.3% had a viral load <400 copies/ml at birth. Saquinavir was well tolerated by the mothers and all newborn children were HIV type-1 negative at 18 months of age.

Efavirenz in human breast milk, mothers', and newborns' plasma

BACKGROUND AND METHODS

Highly active antiretroviral therapy with efavirenz (EFV) has been prescribed to HIV-positive pregnant women in Rwanda (HIV status 1 and CD4 cell count > 350 cells/mm) during the last trimester of pregnancy and for 6 months after delivery. The EFV concentrations in maternal plasma, breast milk and in newborns' plasma of 13 women and their children between 6 weeks and 6 months post partum are reported.

RESULTS

Results show a mean EFV plasma concentration of 6.55 mg/L in maternal plasma, 3.51 mg/L in skim milk, and 0.85 mg/L in infant plasma. Significant linear correlations between maternal plasma and skim milk (r = 0.8666, P < 0.0001) and between skim milk and infant plasma (r = 0.6646, P < 0.02) were found, but no significant correlation was observed between maternal and infant plasma concentrations (P > 0.05).

CONCLUSIONS

After 6 months of breast-feeding, no child out of the 13 had been infected with HIV and all had good psychomotor and growth development. Our results suggest that EFV may be an alternative to nevirapine (NVP) during the third trimester of pregnancy and during the breast-feeding period. Further studies on larger groups of newborns will be necessary to get a better understanding of possible prophylactic protection of the newborns by highly active antiretroviral therapy with EFV given to the mothers.

Pharmacokinetics and safety of nelfinavir when used in combination with zidovudine and lamivudine in HIV-infected pregnant women: Pediatric AIDS Clinical Trials Group (PACTG) Protocol 353

BACKGROUND

Combination antiretroviral regimens including nelfinavir (NFV) are commonly used in pregnancy. We studied the safety, antiviral effect, and pharmacokinetics of NFV and its M8 metabolite with two dosing regimens in combination with zidovudine (ZDV) and lamivudine (3TC) in HIV-infected pregnant women.

METHOD

HIV-infected pregnant women between 14 and 34 weeks gestation received NFV (Cohort 1: 750 mg tid, n = 10; Cohort 2: 1250 mg bid, n = 23) with ZDV and 3TC. Serial blood sampling for NFV concentrations was performed antepartum (AP) and 6 weeks postpartum (PP). Maternal and cord blood samples were also obtained at delivery. NFV and M8 levels were determined by high-performance liquid chromatography. The pharmacokinetic (PK) target was an extrapolated NFV AUC0-24 > 30 mug . h/mL. Mothers were followed frequently for potential clinical and laboratory toxicity.

RESULTS

Overall, NFV in combination with ZDV and 3TC was well tolerated. The PK target was met in 3/8 AP and 5/7 PP in Cohort 1 and 17/21 AP and 16/17 PP in Cohort 2. When Cohort 2 NFV PK parameters AP and PP were compared, median Cmax (3.90 microg/mL vs. 5.01 microg/mL, p < .05) and AUC0-24 (56.6 vs. 86.8 microg . h/mL, p < .05) were increased PP and oral clearance (Cl/F; 44.2 vs. 28.8 L/h, p < .05) was decreased PP. The average M8/NFV ratio was increased PP compared to AP (0.085 vs. 0.29, p < .001). Placental transfer of NFV was low with a median cord blood:maternal plasma ratio at delivery of 0.05. Maternal mean CD4+ T cell counts increased significantly and plasma HIV-1 RNA levels decreased from entry to delivery and 6 to 12 weeks postpartum.

CONCLUSION

NFV used in combination with ZDV and 3TC was well tolerated in pregnant HIV-infected women and produced a significant improvement in HIV disease parameters. NFV drug exposure is inadequate in most pregnant women receiving 750 mg tid but is much improved with 1250 mg bid. NFV crosses the placenta poorly. The AP increase in NFV oral clearance and decrease in M8/NFV ratio suggest that CYP3A activity increases relative to CYP2C19 activity during pregnancy.

The use of prophylaxis against HIV after sexual exposure in pregnancy to reduce the risk of vertical transmission

Summary:

We present a case demonstrating the use of HIV prophylaxis post-sexual exposure in pregnancy. This has not been presented before but has certainly been discussed.

Chronic administration of nevirapine during pregnancy: impact of pregnancy on pharmacokinetics

OBJECTIVES

To determine the impact of pregnancy on the pharmacokinetics (PK) of nevirapine (NVP) during chronic dosing in HIV-infected women and appropriate NVP dosing in this population.

METHODS

Twenty-six pregnant women participating in two open-label Pediatric AIDS Clinical Trials Group studies (P1022 and P1026S) were evaluated. Each patient received 200 mg NVP every 12 h and had PK evaluations during the second or third trimester; these evaluations were repeated postpartum. Paired maternal and cord blood NVP concentrations were collected at delivery in nine patients. Ante- and postpartum comparisons were made using paired t-tests and using a 'bioequivalence' approach to determine confidence interval (CI).

RESULTS

The average NVP Area Under the Curve (AUC) was 56 +/- 13 mcg(*)h/mL antepartum and 61 +/- 15 mcg(*)h/mL postpartum. The typical parameters +/- standard error were apparent clearance (CL/F)=3.51 +/- 0.18 L/h and apparent volume of distribution (Vd/F)=121 +/- 19.8 L. There were no significant differences between antepartum and postpartum AUC or pre-dose concentrations. The AUC ratio was 0.90 with a 90% CI of the mean equal to 0.80-1.02. The median (+/- standard deviation) cord blood to maternal NVP concentration ratio was 0.91 +/- 0.90.

CONCLUSIONS

Pregnancy does not alter NVP PK and the standard dose (200 mg every 12 h) is appropriate during pregnancy.

Pharmacogenetic information derived from analysis of HLA alleles

A large amount of pharmacogenetic information has, in particular, accumulated on the association between human leukocyte antigen (HLA) alleles and hypersensitivity to certain drugs. Prospective HLA typing has dramatically reduced the risk of abacavir hypersensitivity because of its strong association with HLA-B*5701. Significant predisposition to nevirapine hypersensitivity has been reported in Caucasian Australians harboring HLA-DRB1*0101 with high CD4+ T-cell counts, and Sardinians and Japanese harboring HLA-Cw8. A strong association between carbamazepine hypersensitivity and HLA-B*1502 has been reported in Han Chinese. Most Han Chinese individuals with allopurinol-induced severe cutaneous adverse reactions are positive for HLA-B*5801. HLA typing can stratify risk of hypersensitivity to certain drugs and allow personalized treatment, although the patients should be monitored closely even if they are negative for HLA alleles associated with hypersensitivity.

Low Sensitivity of Total Lymphocyte Count as a Surrogate Marker to Identify Antepartum and Postpartum Indian Women Who Require Antiretroviral Therapy

BACKGROUND

Some studies support the use of total lymphocyte count (TLC) as a surrogate marker for CD4 cell count to guide antiretroviral therapy (ART) initiation. However, most of these studies have focused on nonpregnant adults. In light of expanding ART access through prevention of mother-to-child transmission (PMTCT)-plus programs in resource-limited settings, we assessed the sensitivity, specificity, and positive predictive value (PPV) of TLC for predicting low CD4 counts in antepartum and postpartum women in Pune, India.

METHODS

CD4, TLC, and hemoglobin were measured at third trimester, delivery, and 6, 9, and 12 months postpartum (PP) in a cohort of 779 HIV-infected women. Optimal TLC cutoff for predicting CD4 <200 cells/mm3 was determined via logistic regression where sensitivity, specificity, PPV, and an area under the receiver operating characteristic (ROC) curve were calculated.

RESULTS

Among the 779 women enrolled, 16% had WHO clinical stage 2 or higher and 7.9% had CD4 <200 cells/mm3. Using 2689 TLC-CD4 pairs, the sensitivity, specificity, and PPV of TLC <1200 cells/mm3 for predicting CD4 <200 cells/mm3 was 59%, 94%, and 47%, respectively. The sensitivity of TLC <1200 cells/mm3 cutoff ranged between 57% and 62% for time points evaluated. Addition of hemoglobin <12 g/dL or <11 g/dL increased the sensitivity of TLC to 74% to 92% for predicting CD4 <200 cells/mm3 but decreased the specificity to 33% to 69% compared to TLC alone. A combination of TLC, hemoglobin, and WHO clinical staging had the highest sensitivity but lowest specificity compared to other possible combinations or use of TLC alone. The sensitivity and specificity of TLC <1200 cells/mm3 to predict a CD4 <350 cells/mm3 was 31% and 99%, respectively.

CONCLUSIONS

Our data suggest that antepartum and PP women with TLC <1200 cells/mm3 are likely to have CD4 <200 cells/mm3. However, the sensitivity of this TLC cutoff was low. Between 45% and 64% of antepartum and PP women requiring initiation of ART may not be identified by using TLC alone as a surrogate marker for CD4 <200 cells/mm3. The WHO-recommended TLC cutoff of <1200 cells/mm3 is not optimal for identifying antepartum and PP Indian women who require ART.

Management of antiretroviral treatment-related complications

Antiretroviral therapy for HIV restores immune function, controls viral replication, decreases opportunistic infections, and extends lifespan to near-normal for infected individuals. However, successful HIV therapy has been accompanied by the emergence of treatment-related complications, with an impact not yet fully understood. This article reviews six common complications of antiretroviral therapy, including hyperlactatemia/lactic acidosis, hypersensitivity reactions, abnormal glucose metabolism, dyslipidemia, body composition changes, and cardiovascular disease. A comprehensive approach to management of antiretroviral-related complications includes awareness of (1) risk factors for adverse reactions, (2) clinical syndromes suggestive of an evolving complication, and (3) evidence-based monitoring and treatment strategies. Fluency in options for preventing and managing complications can provide maximal opportunity to balance treatment effects with quality of life.

Special care issues of women living with HIV-AIDS

Many HIV-infected women are benefiting from highly active antiretroviral therapy and living longer. Their reproductive choices vary over the life cycle, and there is a need to understand the appropriate contraceptives for those not intending pregnancy. There are specific gynecologic issues relevant to HIV-infected women, such as genital tract infections, risk for cervical cancer, and menstrual irregularities. More women are expected to reach menopause. Health care providers should be aware of these unique needs of HIV-infected women.

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.

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.

Drug-induced liver disease in 2006

PURPOSE OF REVIEW

To identify the key publications of 2006 dealing with drug-induced liver injury.

RECENT FINDINGS

When given in therapeutic doses over 14 days, acetaminophen produced significant asymptomatic elevations in alanine aminotransferase among healthy volunteers, suggesting that subclinical injury may be more common than previously thought. Acute liver failure in children was shown to differ in several important respects from that seen in adults, notably a much lower incidence of acetaminophen toxicity with nearly half of all cases being indeterminate in origin. The first cases of hepatotoxicity with telithromycin, a new class of ketolide antibiotic, were described along with reports suggesting liver injury from ezetimibe among other agents. The potential for chronic injury to develop after acute drug-induced liver injury was analyzed in a large Swedish database; 5-6% of cases were judged to become chronic, with drugs causing cholestatic injury predominating. Among well described hepatotoxins, new reports appeared with highly active antiretroviral therapy agents, herbal therapies and several antibiotics. Finally, the safe use of pravastatin and pioglitazone was demonstrated in patients with chronic liver disease in controlled clinical trials.

SUMMARY

Drug-induced liver injury remains an important concern for many existing drugs as well as for agents in development.

Safety of Agents Used to Prevent Mother-to-Child Transmission of HIV

Antiretroviral drugs have been used routinely to reduce the risk of mother-to-child transmission of HIV infection since 1994, following the AIDS Clinical Trials Group 076 trial, which demonstrated the efficacy of zidovudine in reducing the risk of in utero and intrapartum transmission. The use of antiretroviral drugs in pregnancy varies geographically, with widespread use of highly active antiretroviral therapy (HAART) in resource-rich settings for delaying maternal HIV disease progression as well as the prevention of mother-to-child transmission; however, in low- and middle-income settings, abbreviated prophylactic regimens focus on the perinatal period, with very limited access to HAART to date. The potential risks associated with antiretroviral exposure for pregnant women, fetuses and infants depend on the duration of this exposure as well as the number and type of drugs. As the benefits of HAART regimens in reducing the risk of mother-to-child transmission and in delaying disease progression are so great, their widespread use has been accepted, despite the relative lack of safety data from human pregnancies. Animal studies have suggested an increased risk of malformations associated with exposure to specific antiretroviral drugs, although evidence to support this from human studies is limited. Trials, cohorts and surveillance studies have shown no evidence of an increased risk of congenital malformations associated with in utero exposure to zidovudine, or other commonly used antiretroviral drugs, with an estimated 2-3% prevalence of birth defects (i.e. similar to that seen in the general population). Exposure to prophylactic zidovudine for prevention of mother-to-child transmission is associated with a usually mild and reversible, but rarely severe, anaemia in infants. However, a medium-term impact on haematological parameters of antiretroviral-exposed infants has been reported, with small but persistent reductions in levels of neutrophils, platelets and lymphocytes in children up to 8 years of age; the clinical significance of this remains uncertain. To date, there is no evidence to suggest that exposure to antiretroviral drugs in utero or neonatally is associated with an increased risk of childhood cancer, but the potential for mutagenic and carcinogenic effects at older ages cannot be excluded. Nucleoside analogue-related mitochondrial toxicity is well recognised from studies in non-pregnant individuals, whilst animal studies have provided evidence of mitochondrial toxicity resulting from in utero antiretroviral exposure. Clinically evident mitochondrial disease in children with antiretroviral exposure has only been described in Europe, with an estimated 18-month incidence of 'established' mitochondrial dysfunction of 0.26% among exposed children. Regarding pregnancy-related adverse effects, increased risks of prematurity, pre-eclampsia and gestational diabetes mellitus have been reported by a variety of observational studies with varying strengths of evidence and with conflicting results. Based on current knowledge, the immense benefits of antiretroviral prophylaxis in prevention of mother-to-child transmission far outweigh the potential for adverse effects. However, these potential adverse effects require further and longer term monitoring because they are likely to be rare and to occur later in childhood.

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.