Effectiveness and safety of tenofovir alafenamide in children and adolescents living with HIV: a systematic review.

INTRODUCTION: Tenofovir alafenamide (TAF) is approved for paediatric use in fixed-dose combination tablets, but efficacy and safety data in children are limited. We conducted a systematic review on the efficacy/effectiveness and safety of TAF in infants, children and adolescents living with HIV. METHODS: We searched MEDLINE, Embase, the Cochrane Library, clinical trial registries, reference lists and relevant conferences to identify literature published January 2009-March 2021. We included clinical trials and observational studies assessing the efficacy/effectiveness or safety of TAF through ≥6 months of treatment in participants aged 0-19 years. RESULTS AND DISCUSSION: Overall 3626 abstracts and 371 full papers were screened. Four single-arm, innovator-funded trials (341 participants) and a pooled analysis of those trials were identified. All four trials included treatment-experienced and virally suppressed children or adolescents. One trial also included treatment-naïve adolescents with baseline viral load >1000 copies/ml. The risk of bias was rated as low in one study and unclear in the other three owing to missing data on study design (all conference presentations). At 48 weeks, 92% (46/50) of treatment-naïve participants were virally suppressed (one trial). Among treatment-experienced participants with viral load at 48 weeks, 214 of 224 participants were virally suppressed. Across the studies, one grade 3/4 adverse event was considered drug-related (intermediate uveitis). There were three discontinuations for adverse events (grade 2 anxiety and insomnia, grade 1 iridocyclitis [drug-related] and grade 1 pulmonary tuberculosis [unrelated to treatment]). One accidental death occurred across the four studies. In the pooled analysis of 223 participants, the median change in bone mineral density z-score (height- and age-adjusted) from baseline to 48 weeks was -0.12 (interquartile range [IQR] -0.46, 0.17) to 0.05 (IQR not reported) for spine, and -0.09 (IQR -0.33, 0.07) to 0.09 (IQR not reported) for total body less head. Weight-for-age z-scores increased by 0.25 from baseline to 48 weeks. CONCLUSIONS: Four single-arm trials were identified in this systematic review, with initial evidence suggesting good viral suppression and no obvious safety concerns in children and adolescents on TAF-containing regimens over 24-48 weeks. However, further comparative and longer-term safety data are needed in children and adolescents, including on weight and metabolic changes.

Effectiveness and safety of dolutegravir and raltegravir for treating children and adolescents living with HIV: a systematic review.

INTRODUCTION: Globally about 1.7 million children were living with HIV in 2020. Two integrase strand transfer inhibitors, dolutegravir and raltegravir, are increasingly used in children. We conducted a systematic review to assess the effectiveness and safety of dolutegravir and raltegravir in children and adolescents living with HIV, aged 0-19 years. METHODS: Sources included MEDLINE, Embase, the Cochrane Library, clinical trial registries, abstracts from key conferences and reference list searching. Observational studies and clinical trials published January 2009-March 2021 were eligible. Outcomes included efficacy/effectiveness (CD4 counts and viral load) and/or safety outcomes (mortality, grade 3/4 adverse events and treatment discontinuation) through 6 months or more post-treatment initiation. Risk of bias was assessed using previously published tools appropriate for the study design. Narrative syntheses were conducted. RESULTS AND DISCUSSION: In total, 3626 abstracts and 371 papers were screened. Eleven studies, including 2330 children/adolescents, reported data on dolutegravir: one randomized controlled trial (RCT; low risk of bias), one single-arm trial (unclear risk of bias) and nine cohort studies (three low risk of bias, two unclear risk and four high risk). Ten studies, including 649 children/adolescents receiving raltegravir, were identified: one RCT (low risk of bias), one single-arm trial (low risk of bias) and eight cohort studies (four low risk of bias, three unclear risk and one high risk). Viral suppression levels in children/adolescents at 12 months were high (>70%) in most studies assessing dolutegravir (mostly second- or subsequent-line, or mixed treatment lines), and varied from 42% (5/12) to 83% (44/53) at 12 months in studies assessing raltegravir (mostly second- or subsequent-line). Across all studies assessing dolutegravir or raltegravir, grade 3/4 adverse events (clinical and/or laboratory) were reported in 0-50% of subjects, few resulted in discontinuation, few were drug related and no deaths were attributed to either drug. CONCLUSIONS: These reassuring findings suggest that dolutegravir and raltegravir are effective and safe as preferred regimens in children and adolescents living with HIV. With the rollout of dolutegravir in paediatric populations already underway, it is critical that data are collected on safety and effectiveness in infants, children and adolescents, including on longer-term outcomes, such as weight and metabolic changes.

Safety and efficacy of abacavir for treating infants, children, and adolescents living with HIV: a systematic review and meta-analysis.

BACKGROUND: Abacavir is a nucleoside reverse transcriptase inhibitor recommended in paediatric HIV care. We assessed the safety and efficacy profile of abacavir used in first, second, or subsequent lines of treatment for infants, children, and adolescents living with HIV to inform 2021 WHO paediatric ART recommendations. METHODS: In this systematic review and meta-analysis, we included observational and experimental studies conducted in infants aged 0-1 year, children aged 1-10 years, and adolescents aged 10-19 years living with HIV; with data on safety or efficacy, or both, of abacavir-based antiretroviral therapy (ART); published in English or French between Jan 1, 2009, and Oct 1, 2020, plus an updated search to incorporate studies published between Oct 1, 2020, and May 15, 2022. Studies could be non-randomised or non-comparative and include patients who are treatment-naive or those who previously received abacavir (only if abacavir was combined with other ART). Case studies, studies in adults aged 18 years or older, and those assessing the effect of maternal ART exposure were excluded. We extracted data related to study identifier, study design, study period, setting, population characteristics, ART treatment, and safety (any hypersensitivity reaction, death, grade 3 or 4 adverse events, treatment discontinuation, any other morbidities, and serious adverse events), and efficacy outcomes (HIV viral load and CD4 counts reported at 6 and 12 months after ART initiation). Using random-effect models, we estimated weighted pooled incidence and relative risk (RR) of outcomes. The protocol is published in PROSPERO (CRD42022309230). FINDINGS: Of 1777 records identified, 1475 (83%) were screened after removing duplicates and a further 1421 (96%) were excluded. Of 54 full-text articles assessed for eligibility, 33 (61%) were excluded. Four records were identified from grey literature plus one duplicate from database searching, resulting in 24 studies included (two randomised controlled trials, one single-arm trial, 12 prospective cohorts, seven retrospective cohorts, and two cross-sectional studies). 19 studies described safety data and 15 described efficacy data. 18 (75%) studies were conducted in ART-naive participants. The risk of bias was considered moderate to high for most studies, and all outcomes had significant between-study heterogeneity. Data from 24 265 participants were included, of whom 7236 (30%) received abacavir. Abacavir hypersensitivity reaction was reported in nine (38%) studies, with an incidence ranging from 0·00% to 8·26% (I2=85%; p<0·0001). The incidence of death (reported in seven studies) following abacavir treatment varied from 0·00% to 5·49% (I2=58%; p=0·026). Viral suppression (<400 copies per mL) varied from 50% to 70% at 6 months (I2=92%, p<0·0001) and from 57% to 78% at 12 months (I2=88%, p<0·0001). INTERPRETATION: Toxic effects due to abacavir use remain rare and manageable. Despite scarce data on efficacy, this meta-analysis supports the use of abacavir as a preferred first-line regimen for infants and children living with HIV. FUNDING: WHO.

Accelerating investigation of new HIV drugs in pregnancy: advancing the research agenda from theory to action.

INTRODUCTION: Historical approaches to clinical development of novel therapeutics for treatment and prevention of HIV have led to unacceptable delays in the generation of data to support optimal antiretroviral drug use in pregnancy. Over the last 5 years, multiple stakeholders have voiced their concerns around the exclusion of pregnant women from drug trials, and some progress has been made to consolidate principles and forge consensus. Building on ongoing efforts, the World Health Organization (WHO) and the International Maternal Paediatric Adolescent AIDS Clinical Trials Network (IMPAACT) convened a technical consultation designed to move the discussion from theory to practice. DISCUSSION: Accelerating the inclusion of pregnant women in pre-licensure clinical trials, with a goal to have pharmacokinetics (PK) and preliminary safety data for all new HIV agents in pregnancy available at the time of drug approval, requires: (1) performing non-clinical developmental and reproductive toxicology studies early in drug development for all new HIV agents; (2) recognizing and acting on the central role of women of childbearing potential affected by HIV through the research being conducted and the dissemination of associated results; (3) enrolling pregnant women in studies to specifically determine pregnancy PK and preliminary safety, as soon as late non-clinical studies are completed with no negative signals, for all new HIV agents that have demonstrated preliminary evidence of safety and efficacy from phase 2 trials; (4) investigating adverse pregnancy and birth outcomes through dedicated pregnancy safety studies for all new priority HIV agents; and (5) expanding active surveillance of drug safety in pregnancy for rare events, such as birth defects. Strategic actions to pursue include developing tools and resources to support designing and implementing studies among pregnant and breastfeeding women, identifying and promoting modifications of the regulatory framework that are supportive of systematic ethical investigation of new drugs in pregnancy, coordinating surveillance efforts, mobilizing key stakeholders and promoting transparency and accountability for all involved. CONCLUSIONS: With more than 19 million women living with HIV worldwide, ensuring greater inclusion of pregnant women in research on novel therapeutics is a priority to support drug optimization and effective introduction of innovations for treatment and prevention of HIV.

Surveillance of ARV safety in pregnancy and breastfeeding: towards a new framework.

INTRODUCTION: As new antiretrovirals (ARVs), including long-acting ARVs for treatment and prevention, are approved and introduced, surveillance during pregnancy must become the safety net for evaluating birth outcomes, especially those that are rare and require large numbers of observations. Historically, drug pharmacovigilance in pregnancy has been limited and fragmented between different data sources, resulting in inadequate data to assess risk. The International Maternal Pediatric Adolescent AIDS Clinical Trials Network and World Health Organization convened a Workshop which reviewed strengths and weaknesses of existing programs and discussed an improved framework to integrate existing safety data sources and promote harmonization and digitalization. DISCUSSION: This paper highlights that although robust sources of safety data and surveillance programs exist, key challenges remain, including unknown denominators, reporting bias, under-reporting (e.g. in voluntary registries), few data sources from resource-limited settings (most are in North America and Europe), incomplete or inaccurate data (e.g. within routine medical records). However, recent experiences (e.g. with safety signals) and current innovations (e.g. electronic record use in resource-limited settings and defining adverse outcomes) provide momentum and building blocks for a new framework for active surveillance of ARV safety in pregnancy. A public health approach should be taken using data from existing sources, including registries of pregnancy ARV exposure and birth defects; observational surveillance and cohort studies; clinical trials; and real-world databases. Key facilitators are harmonization and standardization of outcomes, sharing of materials and tools, and data linkages between programs. Other key facilitators include the development of guidance to estimate sample size and duration of surveillance, ensuring strategic geographic diversity, bringing partners together to share information and engaging the community of women living with HIV. CONCLUSIONS: Looking ahead, critical steps to safely introduce new ARVs include (1) adopting harmonized standards for measuring adverse maternal, birth and infant outcomes; (2) establishing surveillance centres of excellence in areas with high HIV prevalence with harmonized data collection and optimized electronic health records linking maternal/infant data; and (3) creating targets and evaluation goals for reporting progress on implementation and quality of surveillance in pregnancy. The platform will be leveraged to ensure that appropriate contributions and strategic actions by relevant stakeholders are implemented.

Effectiveness and Safety of Atazanavir Use for the Treatment of Children and Adolescents Living With HIV: A Systematic Review.

Background: Atazanavir/ritonavir is recommended as a preferred second-line antiretroviral regimen in children older than 3 months, alternatively to lopinavir/ritonavir. We performed a systematic review to assess safety and effectiveness of atazanavir use in children and adolescents. Methods: We searched observational studies and clinical trials on Web of Science, Embase and Cochrane CENTRAL database between 2009/01/01 and 2020/10/01; as well as grey literature. We extracted safety (adverse events, grade 3 or 4 adverse events, treatment discontinuation) and effectiveness (CD4 cell counts and HIV viral load) outcomes. We estimated weighted summary pooled incidence with corresponding 95% confidence intervals. Results: Out of the 1,085 records screened, we included five studies (one comparative cohort, three single phase 2-3 trial arms, one retrospective cohort) reporting 975 children and adolescents, of whom 56% (544) received atazanavir. Three studies reported all-cause treatment discontinuation rates, yielding a pooled incidence of 19% [15-22] at 12 months. The comparative cohort compared atazanavir to darunavir, with few grade 3-4 adverse events, except transient hyperbilirubinemia, occurring in half (92/188) of the atazanavir patients. No death occurred (two studies reporting). Four studies described increased CD4 cell counts and decreased HIV viral load at 6 or 12 months. Conclusion: Few safety and effectiveness data were available for children and adolescents exposed to atazanavir. Transient grade 3-4 hyperbilirubinemia was the main adverse outcome reported. Immune and viral responses were descriptive. The use of atazanavir/ritonavir in children and adolescents needs further investigation, but remains a suitable option for a preferred second-line antiretroviral regimen. PROSPERO number: CRD42022309230.

Evidence synthesis evaluating body weight gain among people treating HIV with antiretroviral therapy - a systematic literature review and network meta-analysis.

Background: This systematic review aimed to compare body weight gain associated outcomes over time between dolutegravir (DTG)-based antiretroviral (ART) regimens to other ART regimens, to compare tenofovir alafenamide (TAF)-based regimens, and to evaluate the associated prognostic factors. Methods: Systematic searches of MEDLINE, Embase, and CENTRAL for RCTs and observational studies comparing ART regimens were conducted on 13 September 2021. Outcomes of interest included: change in body weight, body mass index (BMI), waist circumference; and risk of hyperglycaemia and diabetes. Network meta-analyses were conducted at 12, 24, 48, 96 and 144 weeks using two networks differentiated by 3rd agents and backbone agents. Findings: The review identified 113 publications reporting on 73 studies. DTG-based regimens led to statistically higher weight gains than efavirenz-based regimens at all time points (mean difference: 1·99 kg at 96 weeks; 95% credible interval: 0·85-3·09) and was higher over time than low-dose efavirenz-, elvitegravir-, and rilpivirine-based regimens. They were comparable to raltegravir-, bictegravir- and atazanavir-based regimens. For backbones, TAF led to higher weight gain relative to tenofovir disoproxil fumarate (TDF), abacavir, and zidovudine. Prognostic factor analysis showed both low CD4 cell count and high HIV RNA viral load at baseline were consistently associated with higher weight gain, while sex was an effect modifier to African origins. Interpretation: DTG-based regimens lead to larger average weight gains than some other ART regimens and TAF leads to larger average weight gains than all other backbone antiretrovirals. Further research is needed to better understand long-term outcomes and their relationship to other metabolic outcomes. Funding: The WHO Global HIV, Hepatitis and Sexually Transmitted Infections Programmes.

Enhanced and Timely Investigation of ARVs for Use in Pregnant Women.

BACKGROUND: Concerns have been voiced that the exclusion of pregnant women from clinical trials results in a lack of safety and pharmacokinetic data for antiretroviral drugs (ARVs) in pregnancy, creating clear risks to pregnant women living with HIV (PWLHIV), and their infants. SETTING: The World Health Organization convened a Paediatric Antiretroviral Drug Optimization group meeting, December 10-12, 2018, in Geneva, Switzerland. METHODS: The group, comprised of clinicians, scientists, HIV program managers, regulators, and community representatives, were tasked to consider how ARVs are studied in PWLHIV, define alternative approaches to studying ARVs in PWLHIV, identify ways to shorten the timeline to determine safe use of new agents during pregnancy, and define strategies to collaborate with regulators and industry to change longstanding practices. RESULTS: Most new ARVs are not studied in pregnant populations until after drug licensure, primarily opportunistically among women who become pregnant while taking the ARV of interest. Acceleration of the timeline will require earlier completion of preclinical studies and a new paradigm, namely-under certain conditions-allow women who become pregnant while participating in phase III ARV studies the option of remaining on study and enroll pregnant women into phase III trials of new agents to obtain preliminary safety and dosing and efficacy data. CONCLUSION: A revision of the current approach to the study of antiretrovirals in pregnant women is urgently needed to improve timely access and safe use of new agents during pregnancy.

The Brazilian experience of implementing the active pharmacovigilance of dolutegravir.

In 2017, the Ministry of Health Brazilian started using dolutegravir (DTG) 50 mg to all people living with HIV who began antiretroviral therapy (ART) or rescue regimens. Although DTG is thought to have better tolerability levels and a lower possibility of causing adverse reactions, it is necessary to continuously evaluate the safety profile of the drug in the population. Therefore, an active pharmacovigilance project for DTG was implemented. The objective of this study was to describe the Brazilian experience of implementing pharmacovigilance and the results obtained during the period between April and December 2017.Active pharmacovigilance was implemented through patient interviews and an online questionnaire developed in the Medication Logistics Control System (SICLOM).Of the total number of people on DTG in Brazil (79,742) 90.33% participated in the project, and 2.24% of those who participated reported adverse reactions to the drug; of those who reported adverse reactions, 73.86% were on first-line ART regimens, and 26.13% were on third-line regimens. The mean age of the patients who had adverse reactions to DTG was 39 years; 68.79% were male, and 31.21% were female. Of the adverse reactions reported, 50.39% were considered persistent. The 3 most frequent reactions were nausea (13.34%), diarrhea (9.83%), and headaches (9.23%).The Brazilian experience with this project has been deemed successful by federal and local managers, and the online tool to collect data has proved to be an important strategy for the pharmacovigilance of DTG as well as that of other drugs.

Mapping the landscape of global programmes to evaluate health interventions in pregnancy: the need for harmonised approaches, standards and tools.

Pregnant women and their babies are among the populations most vulnerable to untoward health outcomes. Yet current standards for evaluating health interventions cannot be met during pregnancy because of lack of adequate evidence. The situation is even more concerning in low-income and middle-income countries, where the need for effective interventions is the greatest. Meeting the Sustainable Development Goals for health will require strengthened attention to maternal and child health. In this paper we examine ongoing initiatives aimed at improving the assessment of maternal interventions. We review current methodologies to monitor outcomes of maternal interventions and identify where harmonisation is needed. Based on this analysis we identify settings where different minimal data sets should be considered taking into consideration the clinical realities. Stronger coordination mechanisms and a roadmap to support harmonised monitoring of maternal interventions across programmes and partners, working on improving pregnancy and early childhood health events, will greatly enhance ability to generate evidence-based policies.

Sustainable Monitoring and Surveillance Systems to Improve HIV Programs: Review.

HIV programs have provided a major impetus for investments in surveillance data, with 5-10% of HIV program budgets recommended to support data. However there are questions concerning the sustainability of these investments. The Sustainable Development Goals have consolidated health into one goal and communicable diseases into one target (Target 3.3). Sustainable Development Goals now introduce targets focused specifically on data (Targets 17.18 and 17.19). Data are seen as one of the three systemic issues (in Goal 17) for implementing Sustainable Development Goals, alongside policies and partnerships. This paper reviews the surveillance priorities in the context of the Sustainable Development Goals and highlights the shift from periodic measurement towards sustainable disaggregated, real-time, case, and patient data, which are used routinely to improve programs. Finally, the key directions in developing person-centered monitoring systems are assessed with country examples. The directions contribute to the Sustainable Development Goal focus on people-centered development applied to data.

Safety of Tenofovir Disoproxil Fumarate-Based Antiretroviral Therapy Regimens in Pregnancy for HIV-Infected Women and Their Infants: A Systematic Review and Meta-Analysis.

BACKGROUND: There are limited data on adverse effects of tenofovir disoproxil fumarate (TDF)-based antiretroviral therapy (ART) on pregnant women and their infants. METHODS: We conducted a systematic review of studies published between January 1980 and January 2017 that compared adverse outcomes in HIV-infected women receiving TDF- vs. non-TDF-based ART during pregnancy. The risk ratio (RR) for associations was pooled using a fixed-effects model. RESULTS: Seventeen studies met the study inclusion criteria. We found that the rate of preterm (<37 weeks gestation) delivery (RR = 0.90, 95% confidence interval [CI]: 0.81 to 0.99, I = 59%) and stillbirth (RR = 0.60, 95% CI: 0.43 to 0.84, I = 72.0%) were significantly lower in women exposed (vs. not) to TDF-based ART regimen. We found no increased risk in maternal severe (grade 3) or potentially life-threatening (grade 4) adverse events (RR = 0.62; 95% CI: 0.30 to 1.29), miscarriage (RR = 1.09; 95% CI: 0.80 to 1.48), very preterm (<34 weeks gestation) delivery (RR = 1.08, 95% CI: 0.72 to 1.62), small for gestational age (RR = 0.87, 95% CI: 0.67 to 1.13), low birth weight (RR = 0.91; 95% CI: 0.80 to 1.04), very low birth weight (RR = 3.18; 95% CI: 0.65 to 15.63), congenital anomalies (RR = 1.03; 95% CI: 0.83 to 1.28), infant adverse outcomes or infant mortality (age >14 days) (RR = 0.65; 95% CI: 0.23 to 1.85), but increased neonatal mortality (age <14 days) risk (RR = 5.64, 95% CI: 1.70 to 18.79) with TDR-based ART exposure. No differences were found for anthropomorphic parameters at birth; one study reported minor differences in z-scores for length and head circumference at age 1 year. CONCLUSIONS: TDF-based ART in pregnancy seems generally safe for women and their infants. However, data remain limited and further studies are needed, particularly to assess neonatal mortality and infant growth/bone effects.

Timing of initiation of antiretroviral therapy and adverse pregnancy outcomes: a systematic review and meta-analysis.

BACKGROUND: Although lifelong combination antiretroviral therapy (ART) is recommended for all individuals with HIV, few data exist for pregnancy outcomes associated with ART initiation before conception. We assessed adverse pregnancy outcomes associated with ART initiated before conception compared with that of ART started after conception. METHODS: We did a systematic review of studies from low-income, middle-income, and high-income countries by searching the Cochrane Central Register of Controlled Trials, Embase, LILACS, MEDLINE, Toxline, Web of Knowledge, and WHO Global Index Medicus and trials in progress (International Clinical Trials Registry Platform) for randomised trials, quasi-randomised trials, and prospective cohort studies done between Jan 1, 1980, and June 1, 2016, in which timing of ART initiation in pregnant women living with HIV was reported. We used the risk ratio (RR) and corresponding 95% CIs as the primary measure to assess the association between the selected outcomes and ART initiation before conception versus after conception. We used a random-effects model to pool risk ratios. FINDINGS: We included 11 studies with 19 189 mother-infant pairs. Women who started ART before conception were significantly more likely to deliver preterm (pooled RR 1·20, 95% CI 1·01-1·44) or very preterm (1·53, 1·22-1·92), or to have low-birthweight infants (1·30, 1·04-1·62) than were those who began ART after conception. Few data exist for neonatal mortality. The risk of very low birthweight, small for gestational age, severe small for gestational age, stillbirth, and congenital anomalies did not differ significantly between women who were taking ART before conception and those who began ART after conception. INTERPRETATION: The benefits of ART for maternal health and prevention of perinatal transmission outweigh risks, but data for the extent and severity of these risks are scarce and of low quality. As use of ART before conception rapidly increases globally, monitoring for potential adverse pregnancy outcomes will be crucial. FUNDING: WHO.

The Role of ARV Associated Adverse Drug Reactions in Influencing Adherence Among HIV-Infected Individuals: A Systematic Review and Qualitative Meta-Synthesis.

Poor adherence remains a major barrier to achieving the clinical and public health benefits of antiretroviral drugs (ARVs). A systematic review and qualitative meta-synthesis was conduct to evaluate how ARV adverse drug reactions may influence ARV adherence. Thirty-nine articles were identified, and 33 reported that ARV adverse drug reactions decreased adherence and six studies found no influence. Visually noticeable adverse drug reactions and psychological adverse reactions were reported as more likely to cause non-adherence compared to other adverse drug reactions. Six studies reported a range of adverse reactions associated with EFV-containing regimens contributing to decreased adherence. Informing HIV-infected individuals about ARV adverse drug reactions prior to initiation, counselling about coping mechanisms, and experiencing the effectiveness of ARVs on wellbeing may improve ARV adherence.

Adverse events associated with abacavir use in HIV-infected children and adolescents: a systematic review and meta-analysis.

BACKGROUND: Concerns exist about the toxicity of drugs used in the implementation of large-scale antiretroviral programmes, and documentation of antiretroviral toxicity is essential. We did a systematic review and meta-analysis of adverse events among children and adolescents receiving regimens that contain abacavir, a widely used antiretroviral drug. METHODS: We searched bibliographic databases and abstracts from relevant conferences from Jan 1, 2000, to March 1, 2015. All experimental and observational studies of HIV-infected patients aged 0-18 years who used abacavir, were eligible. Incidence of adverse outcomes in patients taking abacavir (number of new events in a period divided by population at risk at the beginning of the study) and relative risks (RR) compared with non-abacavir regimens were pooled with random effects models. FINDINGS: Of 337 records and 21 conference abstracts identified, nine studies (eight full-text articles and one abstract) collected information about 2546 children, of whom 1769 (69%) were on abacavir regimens. Among children and adolescents taking abacavir, hypersensitivity reactions (eight studies) had a pooled incidence of 2·2% (95% CI 0·4-5·2); treatment switching or discontinuation (seven studies) pooled incidence was 10·9% (2·1-24·3); of grade 3-4 adverse events (six studies) pooled incidence was 9·9% (2·4-20·9); and adverse events other than hypersensitivity reaction (six studies) pooled incidence was 21·5% (2·8-48·4). Between-study inconsistency was significant for all outcomes (p<0·0001 for all inconsistencies). Incidence of death (four studies) was 3·3% (95% CI 1·5-5·6). In the three randomised clinical trials with comparative data, no increased risk of hypersensitivity reaction (pooled RR 1·08; 95% CI 0·19-6·15), grade 3 or 4 events (0·79 [0·44-1·42]), or death (1·72 [0·77-3·82]) was noted for abacavir relative to non-abacavir regimens. None of the reported deaths were related to abacavir. INTERPRETATION: Abacavir-related toxicity occurs early after ART initiation and is manageable. Abacavir can be safely used for first-line or second-line antiretroviral regimens in children and adolescents, especially in sub-Saharan Africa were HLA B5701 genotype is rare. FUNDING: WHO.

Safety of efavirenz in the first trimester of pregnancy: an updated systematic review and meta-analysis.

INTRODUCTION: Primate studies and some observational human data have raised concern regarding an association of first-trimester efavirenz exposure with central nervous system congenital anomalies. The objective of this review is to update evidence on efavirenz safety in HIV-infected pregnant women to inform revision of the 2013 WHO guidelines for antiretroviral therapy in low and middle-income countries. DESIGN: A systematic review and meta-analysis. METHODS: We searched for studies reporting birth outcomes among women exposed to efavirenz during the first trimester of pregnancy up to 10 January 2014. Relative risks of congenital anomalies comparing women exposed to efavirenz and nonefavirenz-based antiretroviral regimens were pooled using random effects meta-analysis. RESULTS: Twenty-three studies were included in this review, among which 21 reported the birth outcomes of 2026 live births among women exposed to efavirenz during the first trimester of pregnancy. Forty-four congenital anomalies were reported, giving a pooled proportion of 1.63% [95% confidence interval (95% CI) 0.78-2.48], with only one neural tube defect. Twelve studies reported birth outcomes of women exposed to efavirenz or nonefavirenz-containing regimens during the first trimester of pregnancy. Pooled analysis found no differences in overall risks congenital anomalies between these two groups (relative risk 0.78, 95% CI 0.56-1.08). The incidence of neural tube defects was low, 0.05% (95% CI <0.01-0.28), and similar to incidence in the general population. DISCUSSION: This updated analysis found no evidence of an increased risk of overall or central nervous system congenital anomalies associated with first-trimester exposure to efavirenz, similar to previous systematic reviews. This review contributed to the evidence base for the revised 2013 WHO guidelines on antiretroviral therapy, which recommend that efavirenz can be included as part of first-line therapy in adults regardless of sex, and that it can be used throughout pregnancy, including during the first trimester. However, because of the low incidence of central nervous system anomalies in the overall population and relatively small number of exposures in the current literature, continued birth outcomes prospective surveillance is warranted.