Quantification of Efavirenz Hydroxymetabolites in Human Plasma Using LC-HRMS/MS.

BACKGROUND: Efavirenz (EFV) is a drug used to treat HIV. Low plasma concentrations of EFV result in suboptimal viral suppression, whereas high concentrations can cause adverse neuropsychiatric side reactions. Some studies have identified a correlation between the plasma concentrations of EFV metabolites and neurotoxicity. To our knowledge, no studies have investigated the metabolism of EFV in young children and its effect on treatment outcomes. Therefore, the aim of this study was to develop and validate a method for quantifying EFV and its metabolites in human plasma derived from children. METHODS: Sample preparation was performed using protein precipitation of 100 µL plasma. Thereafter, an aliquot of the supernatant was used to quantify EFV, 7-hydroxyefavirenz (7-OH-EFV), 8-hydroxyefavirenz (8-OH-EFV), and a newly discovered metabolite ("EFAdeg") associated with 8-OH-EFV. A second aliquot of the supernatant was hydrolyzed using ß-glucuronidase/arylsulfatase and used with the first aliquot to quantify phase II metabolites. The analyses were performed using a Dionex Ultimate 3000RS LC-system coupled with a Q Exactive Orbitrap mass spectrometer. RESULTS: The method has a measuring range of 100-50,000 ng/mL (EFV, 8-OH-EFV), 125-25,000 ng/mL (7-OH-EFV), and 200-10,000 ng/mL ("EFAdeg"). All criteria of the European Medicines Agency guidelines regarding precision, accuracy, and selectivity were met. Of note, carryover must be considered for 8-OH-EFV. Overall, the validated method was successfully applied to plasma samples obtained from children and confirmed the presence of the newly discovered metabolite, "EFAdeg." CONCLUSIONS: An LC-HRMS/MS method for the quantification of EFV and its phase I and II metabolites was developed and validated. This method is suitable for analyzing plasma samples from children. Furthermore, studies using this method identified an additional metabolite that may influence the concentration of 8-OH-EFV in patient samples.

Prophylaxis and treatment of HIV infection in pregnancy, Swedish guidelines 2024.

In May 2024, the Swedish Reference Group on Antiviral Therapy updated the guidelines on management of HIV infection in pregnancy. The most important recommendations and revisions were: (i) ART during pregnancy should be started as early as possible and continue after delivery; (ii) Suppressive ART should normally not be modified; (iii) The treatment target of HIV RNA <20 copies/ml remains; (iv) Dolutegravir/emtricitabine/tenofovir DF is the first-line drug combination also in pregnant women and women planning pregnancy; (v) There is no evidence of an increased risk of neural tube defects associated with dolutegravir; (vi) Mode of delivery for women with effective ART and HIV RNA <200 copies/ml should follow standard obstetric procedures; (vii) Caesarean section is recommended if HIV RNA ≥200 copies/ml; (viii) Scalp electrode, foetal blood sampling and/or vacuum delivery should be used on strict indications, but does not necessitate intensified infant prophylaxis; (ix) Management and mode of delivery in case of premature or full-term rupture of membranes should follow standard obstetric procedures; (x) Recommended infant antiretroviral prophylaxis has been updated; (xi) The duration of infant antiretroviral prophylaxis (gestational age ≥35 weeks and mother on effective ART and HIV RNA <200 copies/ml) has been changed from 4 to 2 weeks; (xii) Infants born to women with HIV RNA ≥200 copies/ml should receive 4 weeks of combination prophylaxis; (xiii) Fertility evaluation and assisted reproduction should be offered to women on suppressive ART according to the same principles as for other women; (xiv) Women living with HIV should still be advised against breastfeeding; (xv) Women who nevertheless opt to breastfeed should be offered intensified support and follow-up.

Growth, weight gain and BMI in virally suppressed children on antiretroviral therapy with specific reference to dolutegravir.

BACKGROUND: Pediatric HIV infection cause retardation in height and weight. However, effective antiretroviral therapy (ART) result in desirable weight gain. Concerns have emerged regarding excessive weight gain related to the integrase inhibitor dolutegravir in adults but knowledge about the circumstances in children/adolescents is limited. We studied if dolutegravir containing ART or switch to dolutegravir affected body mass index (BMI) and described height development in the Stockholm pediatric/adolescent HIV cohort. METHODS: A retrospective cohort study of height, weight and BMI in relation to ART in 94 children/adolescents living with HIV. RESULTS: At last documented visit 60/94 children/adolescents were on dolutegravir, 50 had switched from a protease inhibitor or non-nucleoside reverse transcriptase inhibitor. Height standard deviation score (SDS) increased between first and last visit from mean height SDS -0.88 (16 had SDS < -2 and 6 SDS < -3) to -0.32 (four had SDS < -2). Mean BMI SDS increased from -0.15 to 0.62 in girls, but not (-0.20 to 0.09) in boys. The number of girls ≥ 12 years with BMI SDS ≥ 2 increased significantly from 0/38 to 8/38 and totally 9/50 (18%) girls and 4/44 (9%) boys had BMI SDS ≥ 2 at last visit. There was no difference in height or weight gain between different ART regimens. BMI SDS remained stable in 22/50 children switching to dolutegravir, decreased in 13 and increased in 15. CONCLUSION: Adolescent girls gained weight to a greater extent than expected but independently of ART. We found no association between dolutegravir alone or combined with tenofovir alafenamide fumarate (TAF) and excessive weight gain. Height development was within normal range.

Pretreatment HIV drug resistance predicts accumulation of new mutations in ART-naïve Ugandan children.

AIM: To assess the prevalence of pretreatment drug resistance (PDR) and its association with virologic outcomes after 24 weeks of antiretroviral therapy (ART), within an urban cohort of Ugandan children. METHODS: Prospective observational study. Baseline and 24-week assessments of viral load (VL) and genotypic drug resistance to nucleoside reverse transcriptase inhibitors (NRTI) and non-nucleoside reverse transcriptase inhibitors (NNRTI) were performed. RESULTS: Ninety-nine ART-naïve children (3-12 years) initiated efavirenz-based ART 2015-2016 and 18/90 (20%) had baseline NRTI/NNRTI associated drug resistance mutations (DRMs). By 24 weeks, 72/93 (77%) children had VL < 40 copies/mL and a total of 23 children had DRMs. Children with PDR accumulated new DRMs with a mean number (SD) of 1.4 (2.35) new mutations compared to 0.26 (0.98) in 67 children with wild-type virus (P = .003). High pretreatment VL and PDR (number of baseline DRMs) predicted viremia (P = .003; P = .023) as well as acquired drug resistance (P = .02; P = .04). CONCLUSION: Pretreatment drug resistance to NNRTI/NRTI was common among ART-naïve Ugandan children and predicted viremia and new resistance mutations after only 24 weeks of efavirenz-based therapy. PDR may compromise long-term ART outcomes-especially when access to resistance testing and VL monitoring is poor. The long-term importance of PDR for non-NNRTI-based regimens needs further evaluation.

Dolutegravir in pregnancy-effects on HIV-positive women and their infants.

The development of new drugs for treatment of HIV has increased the efficacy and the quality of life together with decreased unwanted side-effect for people living with HIV. The integrase inhibitor dolutegravir has in short time become part of the first-line treatment in many countries, but is not a recommended first-line drug in pregnancy. As there are few publications of dolutegravir use during pregnancy, we found it valuable to analyze the Stockholm pregnancy cohort. A retrospective analysis of all pregnant women and their infants exposed to dolutegravir at Karolinska University Hospital, 2014-August 2017. Information about maternal health, treatment, pregnancy, and child outcome were collected. Thirty-six women with singleton pregnancies were included. Four early spontaneous abortions occurred. One late termination was performed and one was lost to follow-up. Fourteen were on dolutegravir before and 22 started during pregnancy. Eighteen delivered by caesarean section, three of them because of HIV RNA > 50 copies/mL. The preeclampsia rate and the maternal liver function were normal. One infant was delivered in GW 34 on maternal indication and the rest in full term. No gross malformations were noted. All infants received antiretroviral prophylaxis and have tested negative on follow-up. No increased maternal or infant morbidity was detected in this retrospective study of dolutegravir during pregnancy. This is so far one of the largest observational studies of dolutegravir treatment during pregnancy, but the number is indeed small, and further studies are needed to evaluate the safety and efficacy.

Genetic variants in CYP2B6 and CYP2A6 explain interindividual variation in efavirenz plasma concentrations of HIV-infected children with diverse ethnic origin.

BACKGROUND: Approximately 2.6 million children live with HIV globally, and efavirenz (EFV) is one of the most widely used antiretroviral agents for HIV treatment in children and adults. There are concerns about the appropriateness of current EFV dosing and it has been discussed whether EFV dosing should be adapted according to genotype in children as suggested for adults. AIM: To investigate if pediatric EFV dosing should be guided by genetic variation in drug metabolizing enzymes rather than by body weight. METHOD: EFV plasma concentrations measured for clinical purposes from all children less than 18 years old at Karolinska University Hospital, Stockholm, Sweden, treated with EFV were collected retrospectively. They were genotyped for eleven polymorphisms in genes coding for drug-metabolizing enzymes and P-glycoprotein, of potential importance for EFV disposition. Data on country of origin, sex, age, weight, HIV RNA, viral resistance patterns, CD4 cells, adherence to treatment, subjective health status and adverse events were collected from their medical records. RESULTS: Thirty-six patients and 182 (mean 5 samples/patient) EFV plasma concentration measurements from children of African, Asian and Latin American origin were included. EFV plasma concentration varied 21-fold between measurements (n = 182) (0.85-19.3 mg/L) and 9-fold measured as mean EFV plasma concentration across the subjects (1.55-13.4 mg/L). A multivariate mixed-effects restricted maximum likelihood regression model, including multiple gene polymorphisms, identified CYP2B6*6 T/T (p < 0.0005), CYP2B6*11 G/G (p < 0.0005), CYP2A6*9 A/C (p = 0.001) genotypes, age at treatment initiation (p = 0.002) and time from treatment initiation (p < 0.0005) as independent factors significantly related to loge concentration/(dose/weight). The contribution of the model to the intra- and interindividual variation were 6 and 75%, respectively (Bryk/Raudenbush R-squared level). CONCLUSION: Genetic polymorphisms in CYP2B6 and CYP2A6 explained a significant proportion of variability in EFV plasma concentration in HIV-infected children in a multi-ethnic outpatient clinic. Knowledge about individual variants in key drug metabolizing enzyme genes could improve clinical safety and genotype directed dosing could achieve more predictable EFV plasma concentrations in HIV-infected children.

Hepatitis B Virus Vaccination in HIV-1-Infected Young Adults: A Tool to Reduce the Size of HIV-1 Reservoirs?

During anti-retroviral therapy (ART) HIV-1 persists in cellular reservoirs, mostly represented by CD4+ memory T cells. Several approaches are currently being undertaken to develop a cure for HIV-1 infection through elimination (or reduction) of these reservoirs. Few studies have so far been conducted to assess the possibility of reducing the size of HIV-1 reservoirs through vaccination in virologically controlled HIV-1-infected children. We recently conducted a vaccination study with a combined hepatitis A virus (HAV) and hepatitis B virus (HBV) vaccine in 22 HIV-1-infected children. We assessed the size of the virus reservoir, measured as total HIV-1 DNA copies in blood cells, pre- and postvaccination. In addition, we investigated by immunostaining whether the frequencies of CD4+ and CD8+ T cells and parameters of immune activation and proliferation on these cells were modulated by vaccination. At 1 month from the last vaccination dose, we found that 20 out of 22 children mounted a serological response to HBV; a majority of children had antibodies against HAV at baseline. The number of HIV-1 DNA copies in blood at 1 month postvaccination was reduced in comparison to baseline although this reduction was not statistically significant. A significant reduction of HIV-1 DNA copies in blood following vaccination was found in 12 children. The frequencies of CD4+ (naïve, effector memory) and CD8+ (central memory) T-cell subpopulations changed following vaccinations and a reduction in the activation and proliferation pattern of these cells was also noticed. Multivariate linear regression analysis revealed that the frequency of CD8+ effector memory T cells prior to vaccination was strongly predictive of the reduction of HIV-1 DNA copies in blood following vaccination of the 22 HIV-1-infected children. The results of this study suggest a beneficial effect of vaccination to reduce the size of virus reservoir in HIV-1-infected children receiving ART. A reduced frequency of activated CD4+ cells and an increase in central memory CD8+ T cells were associated with this finding. Further studies should assess whether vaccination is a possible tool to reduce HIV-1 reservoirs.

Pharmacogenetics of non-nucleoside reverse transcriptase inhibitors (NNRTIs) in resource-limited settings: Influence on antiretroviral therapy response and concomitant anti-tubercular, antimalarial and contraceptive treatments.

The burden of human immunodeficiency virus (HIV) is mainly concentrated to resources-limited countries where the response to available antiretroviral therapy is often limited by the occurrence of toxicity or by the emergence of HIV drug resistance. Efavirenz and nevirapine are the antiretroviral drugs most prescribed in resources-limited countries as part of antiretroviral combination therapy. Their metabolism and conjugation are largely influenced by enzymatic genetic polymorphisms. The genetic variability of their metabolism could be associated to different metabolic phenotypes causing reduced patients' adherence because of toxicity or drug-drug interactions with concomitant therapies. The purpose of this review is to summarize published evidence on pharmacogenetic and pharmacokinetic aspects related to efavirenz and nevirapine, the influence of concomitant anti-tubercular, anti-malarial or contraceptive treatments, and the impact of human genetic variation and drug-drug interaction on the virologic and immunologic response to antiretroviral therapy in resources-limited countries.

Maintenance of remission with cyclosporine in paediatric patients with Kimura's disease - two case reports.

UNLABELLED: Here we report two paediatric cases of Kimura's disease, which is a rare, chronic inflammatory disorder with undetermined aetiology. The first patient was a 17-year-old boy presenting with a swelling behind his right ear and a nephrotic syndrome. The second patient was a 9-year-old boy presenting with a left-sided preauricular swelling. Both displayed peripheral blood eosinophilia, raised levels of serum IgE and typical histological findings. Initial response to prednisolone was excellent but both relapsed as medication was tapered or discontinued. Adding cyclosporine to the regimen resulted in prolonged remission in both patients. CONCLUSION: We support the use of cyclosporine for maintaining remission in paediatric patients with Kimura's disease.

Antenatal renal pelvis dilatation: 2-year follow-up with DMSA scintigraphy.

The aim of this study was to determine whether a postnatal ultrasound (US) can detect infants with antenatal renal pelvis dilatation (ARPD) who run a minimal risk of renal damage 2 years after birth. The study cohort consisted of 14,000 pregnant women who consecutively underwent routine US examinations during the second trimester. Subsequent examinations were performed on the basis of obstetrical indications. In total, 106 foetuses were diagnosed with ARPD > or =5 mm. Two postnatal US were performed on the newborns: on postpartum days 5-7 and during the third week of life. The findings were considered to be normal when the renal pelvis diameter (RPD) was < or = 7 mm and when there was no calyceal or ureteric dilatation or signs of renal dysplasia or other anomalies. Voiding cystourethrography (VCUG) was done at 6-8 weeks after birth. When the children reached 2 years of age, renal status was evaluated with DMSA scintigraphy or, if not possible, US. In 53 of the 103 children available for evaluation, the postnatal US findings were normal; 49 of the 53 children were also given a DMSA, and the results were normal in all cases. An US scan (all normal) only was performed in three children because the families refused a DMSA. One family refused any form of examination at the 2-year follow-up. Based on our results, we conclude that postnatal US can detect infants who do not require follow-up assessments of renal development.