Clinical considerations and pharmacokinetic interactions between HIV and tuberculosis therapeutics.

INTRODUCTION: Tuberculosis(TB) is a leading infectious diseases cause of mortality worldwide,especially for people living with human immunodeficiency virus(PLWH). Treating TB in PLWH can be challenging due to numerous druginteractions. AREASCOVERED: Thisreview discusses drug interactions between antitubercular andantiretroviral drugs. Due to its clinical importance, initiation ofantiretroviral therapy in patients requiring TB treatment isdiscussed. Special focus is placed on the rifamycin class, as itaccounts for the majority of interactions. Clinically relevantguidance is provided on how to manage these interactions. Anadditional section on utilizing therapeutic drug monitoring (TDM) tooptimize drug exposure and minimize toxicities is included. EXPERTOPINION: Antitubercularand antiretroviral coadministration can be successfully managed. TDMcan be used to optimize drug exposure and minimize toxicity risk. Asnew TB and HIV drugs are discovered, additional research will beneeded to assess for clinically relevant drug interactions.

HIV symptom severity and associated factors among young people with HIV in Ghana.

ABSTRACTAdolescents and young adults (young people) with HIV (YPWH) often struggle with treatment self-management. Many have symptoms due to HIV disease, medication side-effects, or comorbid conditions. Our study investigated the severity of HIV-related symptoms among YPWH aged 18-24 with detectable viral loads from an HIV clinic in Ghana (N = 60) and potential correlates of severity across a range of factors. Results indicated that YPWH currently experienced, on average, 13 symptoms (SD = 12.33). Six of the 10 most common symptoms were from two domains: fatigue and psychological. The most common symptoms were headaches (62%), weakness (53%), and fear/worries (52%). No differences were observed in number or severity of symptoms between youth based on HIV transmission status. Bivariate correlates of symptom severity were found with six that remained significant or approached significance in a multivariate model predicting severity: living with a parent/guardian, higher perceived access to HIV care, and higher treatment readiness were associated with lower severity while greater travel time to the HIV clinic, psychological distress, and more missed clinic appointments were associated with higher severity. Our findings suggest that interventions to address symptoms among YPWH should be multilevel and include strategies (e.g., telehealth, home care) to increase access to care.

Depression and Anxiety Symptoms and Treatment Utilization, and Associated HIV Outcomes among Adults with HIV in Rural Florida.

Persons living with HIV (PLWH) and depression or anxiety in the rural South may have suboptimal HIV outcomes. We sought to examine the proportion of PLWH from rural Florida with symptoms of depression or anxiety, the proportion who received depression or anxiety treatment, and the relationship between untreated and treated symptoms of depression or anxiety and HIV outcomes. Cross-sectional survey data collected between 2014 and 2018 were analyzed. Among 187 PLWH residing in rural Florida (median age 49 years, 61.5%, male 45.5% Black), 127 (67.9%) met criteria for symptoms of depression and/or anxiety. Among these 127 participants, 60 (47.2%) were not on depression or anxiety treatment. Participants with untreated symptoms of depression and anxiety (OR 3.2, 95% CI 1.2-9.2, p = 0.03) and treated depression and anxiety with uncontrolled symptoms (OR 1.4, 95% CI 0.5-4.0, p = 0.52) were more likely to have viral non-suppression compared to those without depression or anxiety in an unadjusted bivariate analysis. Only the association between untreated symptoms of depression and anxiety and viral non-suppression was statistically significant, and when adjusting for social and structural confounders the association was attenuated and was no longer statistically significant. This suggests that social and structural barriers impact both mental health and HIV outcomes. Our findings support the need for increased mental health services and resources that address the social and structural barriers to care for PLWH in the rural South.

A Randomized Clinical Trial of Bayesian-Guided Beta-Lactam Infusion Strategy and Associated Bacterial Resistance and Clinical Outcomes in Patients With Severe Pneumonia.

BACKGROUND: Antimicrobial resistance is a growing health concern worldwide. The objective of this study was to evaluate the effect of beta-lactam infusion on the emergence of bacterial resistance in patients with severe pneumonia in the intensive care unit. METHODS: Adult intensive care patients receiving cefepime, meropenem, or piperacillin-tazobactam for severe pneumonia caused by Gram-negative bacteria were randomized to receive beta-lactams as an intermittent (30 minutes) or continuous (24 hours) infusion. Respiratory samples for culture and susceptibility testing, with minimum inhibitory concentrations (MIC), were collected once a week for up to 4 weeks. Beta-lactam plasma concentrations were measured and therapeutic drug monitoring was performed using Bayesian software as the standard of care. RESULTS: The study was terminated early owing to slow enrollment. Thirty-five patients were enrolled in this study. Cefepime (n = 22) was the most commonly prescribed drug at randomization, followed by piperacillin (n = 8) and meropenem (n = 5). Nineteen patients were randomized into the continuous infusion arm and 16 into the intermittent infusion arm. Pseudomonas aeruginosa was the most common respiratory isolate (n = 19). Eighteen patients were included in the final analyses. No differences in bacterial resistance were observed between arms ( P = 0.67). No significant differences in superinfection ( P = 1), microbiological cure ( P = 0.85), clinical cure at day 7 ( P = 0.1), clinical cure at end of therapy ( P = 0.56), mortality ( P = 1), intensive care unit length of stay ( P = 0.37), or hospital length of stay ( P = 0.83) were observed. Achieving 100% ƒT > MIC ( P = 0.04) and ƒT > 4 × MIC ( P = 0.02) increased likelihood of clinical cure at day 7 of therapy. CONCLUSIONS: No differences in the emergence of bacterial resistance or clinical outcomes were observed between intermittent and continuous infusions. Pharmacokinetic/pharmacodynamic target attainment may be associated with a clinical cure on day 7.

Association of tenofovir diphosphate and lamivudine triphosphate concentrations with HIV and hepatitis B virus viral suppression.

OBJECTIVE: Concentrations of tenofovir diphosphate (TFV-DP) and lamivudine triphosphate (3TC-TP) in cells are correlates of medication adherence and antiviral activity. However, studies have yet to characterize the simultaneous relationship between TFV-DP and 3TC-TP concentrations with HIV and hepatitis B virus (HBV) suppression. METHODS: Individuals with HIV/HBV coinfection on tenofovir disoproxil fumarate (TDF)-containing antiretroviral therapy (ART) were enrolled. Peripheral blood mononuclear cells (PBMCs) and dried blood spots (DBS) samples were collected and steady-state TFV-DP and 3TC-TP concentrations quantified using validated methods. The relationship between patient factors, TFV-DP, and 3TC-TP concentrations in PBMCs and DBS with HBV and HIV viral suppression were examined. RESULTS: Of 138 participants on TDF-containing ART for a median duration (range) of 6 (0.75-15) years, the median age was 43 years and 64% were women. Overall, 128 (92.8%) and 129 (93.5%) had suppressed HIV and HBV viral loads, respectively. Of the 128 participants with suppressed HIV, 122 (95.3%) had suppressed HBV. Self-reported ART adherence, recent change to dolutegravir-based ART, TFV-DP, and 3TC-TP concentrations in PBMCs and DBS were associated with HIV RNA suppression, while HBe antigen positivity, HIV suppression, and TFV-DP concentrations in DBS were associated with HBV DNA suppression (including six persons with HBV nonsuppression and HIV suppression). CONCLUSION: Long-term TDF/3TC-conatining ART was highly efficacious in individuals with HIV/HBV coinfection. Higher TFV-DP concentrations were predictive of suppression for both viruses. Persistent HBV viremia on TDF/3TC-containg ART requires additional research, but may represent poor adherence and the need for adherence interventions or novel antivirals.

Pharmacokinetics and pharmacodynamics of adult dolutegravir tablets in treatment-experienced children with HIV weighing at least 20 kg.

OBJECTIVE: Limited pharmacokinetic/pharmacodynamic data are a barrier to the scale-up of dolutegravir-based antiretroviral therapy (ART) in children. We examined the pharmacokinetics/pharmacodynamics of the adult film-coated dolutegravir 50 mg tablets in children with HIV infection weighing at least 20 kg. DESIGN: A prospective, observational, pharmacokinetic, and safety study. METHODS: Treatment-experienced children with HIV weighing at least 20 kg and evidence of viral load suppression on ART were enrolled and switched to dolutegravir-based therapy. After at least 4 weeks and 7 months on dolutegravir-based therapy, blood samples were collected at 0, 1, 4, 8, 12, and 24-h postdose. Dolutegravir concentrations were measured using validated LCMS/MS and pharmacokinetic parameters calculated by noncompartmental analysis. Descriptive statistics were used to summarize pharmacokinetic parameters and comparisons with published reference values. RESULTS: Of 25 participants, 92% were on efavirenz-based ART and 60.0% were men. Dolutegravir mean exposure, peak and trough concentrations at both pharmacokinetic visits were higher than the mean reference values in adults and children weighing 20 kg to less than 40 kg treated with 50 mg once daily, but were closer to the mean values in adults given 50 mg twice a day. Children weighing 20 kg to less than 40 kg had even higher dolutegravir exposures. The regimens were well tolerated with good virologic efficacy through week 48. CONCLUSION: The higher dolutegravir exposure in our study population suggests that further studies and close monitoring should investigate the adverse effects of dolutegravir in more children and in the long term.

Global estimates and determinants of antituberculosis drug pharmacokinetics in children and adolescents: a systematic review and individual patient data meta-analysis.

BACKGROUND: Suboptimal exposure to antituberculosis (anti-TB) drugs has been associated with unfavourable treatment outcomes. We aimed to investigate estimates and determinants of first-line anti-TB drug pharmacokinetics in children and adolescents at a global level. METHODS: We systematically searched MEDLINE, Embase and Web of Science (1990-2021) for pharmacokinetic studies of first-line anti-TB drugs in children and adolescents. Individual patient data were obtained from authors of eligible studies. Summary estimates of total/extrapolated area under the plasma concentration-time curve from 0 to 24 h post-dose (AUC0-24) and peak plasma concentration (C max) were assessed with random-effects models, normalised with current World Health Organization-recommended paediatric doses. Determinants of AUC0-24 and C max were assessed with linear mixed-effects models. RESULTS: Of 55 eligible studies, individual patient data were available for 39 (71%), including 1628 participants from 12 countries. Geometric means of steady-state AUC0-24 were summarised for isoniazid (18.7 (95% CI 15.5-22.6) h·mg·L-1), rifampicin (34.4 (95% CI 29.4-40.3) h·mg·L-1), pyrazinamide (375.0 (95% CI 339.9-413.7) h·mg·L-1) and ethambutol (8.0 (95% CI 6.4-10.0) h·mg·L-1). Our multivariate models indicated that younger age (especially <2 years) and HIV-positive status were associated with lower AUC0-24 for all first-line anti-TB drugs, while severe malnutrition was associated with lower AUC0-24 for isoniazid and pyrazinamide. N-acetyltransferase 2 rapid acetylators had lower isoniazid AUC0-24 and slow acetylators had higher isoniazid AUC0-24 than intermediate acetylators. Determinants of C max were generally similar to those for AUC0-24. CONCLUSIONS: This study provides the most comprehensive estimates of plasma exposures to first-line anti-TB drugs in children and adolescents. Key determinants of drug exposures were identified. These may be relevant for population-specific dose adjustment or individualised therapeutic drug monitoring.

Assessing risk factors for latent and active tuberculosis among persons living with HIV in Florida: A comparison of self-reports and medical records.

PURPOSE: This study examined factors associated with TB among persons living with HIV (PLWH) in Florida and the agreement between self-reported and medically documented history of tuberculosis (TB) in assessing the risk factors. METHODS: Self-reported and medically documented data of 655 PLWH in Florida were analyzed. Data on sociodemographic factors such as age, race/ethnicity, place of birth, current marital status, education, employment, homelessness in the past year and 'ever been jailed' and behavioural factors such as excessive alcohol use, marijuana, injection drug use (IDU), substance and current cigarette use were obtained. Health status information such as health insurance status, adherence to HIV antiretroviral therapy (ART), most recent CD4 count, HIV viral load and comorbid conditions were also obtained. The associations between these selected factors with self-reported TB and medically documented TB diagnosis were compared using Chi-square and logistic regression analyses. Additionally, the agreement between self-reports and medical records was assessed. RESULTS: TB prevalence according to self-reports and medical records was 16.6% and 7.5% respectively. Being age ≥55 years, African American and homeless in the past 12 months were statistically significantly associated with self-reported TB, while being African American homeless in the past 12 months and not on antiretroviral therapy (ART) were statistically significantly associated with medically documented TB. African Americans compared to Whites had odds ratios of 3.04 and 4.89 for self-reported and medically documented TB, respectively. There was moderate agreement between self-reported and medically documented TB (Kappa = 0.41). CONCLUSIONS: TB prevalence was higher based on self-reports than medical records. There was moderate agreement between the two data sources, showing the importance of self-reports. Establishing the true prevalence of TB and associated risk factors in PLWH for developing policies may therefore require the use of self-reports and confirmation by screening tests, clinical signs and/or microbiologic data.

Preferences for a Game-Based SMS Adherence Intervention Among Young People Living with HIV in Ghana: A Qualitative Study.

Young people living with HIV (YPLH) are at risk for poor treatment adherence. Short message service (SMS) interventions can improve adherence, yet few exist for YPLH. Our study investigated preferences for a game-based SMS intervention among YPLH in Ghana. Thirty-two YPLH, ages 18 to 24, were recruited from an HIV clinic to complete in-depth interviews. Content analysis of interview data revealed areas of technology use relevant to intervention implementation, including mobile communication preferences, internet access, and mobile game use. Participants reported high perceived utility towards intervention features: treatment reminders, gamification components, and involvement of supportive individuals (e.g., providers). Issues with privacy, literacy, and cultural/developmental appropriateness were among concerns raised. Suggestions were made for strengthening basic SMS features (e.g., using code words to protect privacy) and incorporating advanced features (e.g., simplifying game interactions). This novel approach may help engage YPLH in HIV care if carefully developed with attention towards its mechanisms and user preferences.

Childhood tuberculosis and factors associated with mortality and loss to follow-up at a major paediatric treatment centre in Southern Ghana.

Introduction: tuberculosis (TB) is a major cause of morbidity and mortality in children in low- and middle-income countries. This study described the clinical presentation and identified factors contributing to poor outcome of childhood TB at Korle Bu Teaching Hospital (KBTH), Accra, Ghana. Methods: this was a retrospective cohort study of children aged ≤ 14 years with TB registered for treatment at KBTH from 2015 to 2019. Treatment outcomes were recorded as treatment success and unsuccessful outcomes (died and loss to follow-up). Multivariable logistics regression was conducted to assess factors associated with an unsuccessful outcome. Results: of 407 children with TB registered during the period, 269 (66.1%) patients had pulmonary tuberculosis (PTB). Of the 138 patients with extra-pulmonary TB (EPTB), 68 (49.3%) had TB lymphadenitis. The TB/HIV coinfection rate was 42.8%. The overall treatment success rate was 68.3%, whilst 71(17.4%) died, and 58 (14.3%) were lost to follow-up. Factors associated with death were age below 1 year (AOR: 3.46, 95% CI: 1.48-8.10, p=0.004) and having HIV coinfection (AOR: 1.89, 95% CI: 1.04-3.43, p=0.037). Factors associated with loss to follow-up were age below 1 year (AOR: 2.91, 95% CI: 1.12-8.59, p=0.029) and having EPTB (AOR: 2.40, 95% CI: 1.24-4.65, p=0.009). Conclusion: childhood TB treatment success in our population was below the national target of 85%, with high mortality and loss to follow-up rates, especially in younger children and those with HIV coinfection or EPTB. Tailored treatment strategies may be needed for children at risk of unsuccessful treatment outcome, especially among infants.

Could pharmacogenetics aid the prediction of nevirapine pharmacokinetics and allow individualized treatment?

Tweetable abstract The large interindividual variability in nevirapine pharmacokinetics and clinical effects that remains unexplained by pharmacogenetic prediction is a major limitation for individualized nevirapine treatment.

Tweetable abstract The large interindividual variability in nevirapine pharmacokinetics and clinical effects that remains unexplained by pharmacogenetic prediction is a major limitation for individualized nevirapine treatment.

HIV virological non-suppression and its associated factors in children on antiretroviral therapy at a major treatment centre in Southern Ghana: a cross-sectional study.

BACKGROUND: Children living with human immunodeficiency virus (HIV) infection require lifelong effective antiretroviral therapy (ART). The goal of ART in HIV-infected persons is sustained viral suppression. There is limited information on virological non-suppression or failure and its associated factors in children in resource limited countries, particularly Ghana. METHODS: A cross-sectional study of 250 children aged 8 months to 15 years who had been on ART for at least 6 months attending the Paediatric HIV clinic at Korle Bu Teaching hospital in Ghana was performed. Socio-demographic, clinical, laboratory and ART Adherence related data were collected using questionnaires as well as medical records review. Blood samples were obtained for viral load and CD4+ count determination. Viral load levels > 1000 copies/ml on ART was considered virological non-suppression. Logistic regression was used to identify factors associated with virological non-suppression. RESULTS: The mean (±SD) age of the study participants was 11.4 ± 2.4 years and the proportion of males was 53.2%. Of the 250 study participants, 96 (38.4%) had virological non-suppression. After adjustment for significant variables, the factors associated with non-suppressed viral load were female gender (AOR 2.51 [95% CI 1.04-6.07], p = 0.041), having a previous history of treatment of tuberculosis (AOR 4.95 [95% CI 1.58-15.5], p = 0.006), severe CD4 immune suppression status at study recruitment (AOR 24.93 [95% CI 4.92-126.31], p < 0.001) and being on a nevirapine (NVP) based regimen (AOR 7.93 [95% CI 1.58-1.15], p = 0.005). CONCLUSION: The prevelance of virological non-suppression was high. Virological non-suppression was associated with a previous history of TB treatment, female gender, severe CD4 immune suppression status at study recruitment and being on a NVP based regimen. Early initiation of ART and phasing out NVP-based regimen might improve viral load suppression in children. In addition, children with a history of TB may need focused measures to maximize virological suppression.

Pharmacogenetic predictors of nevirapine pharmacokinetics in Ghanaian children living with HIV with or without TB coinfection.

Nevirapine (NVP) is a non-nucleoside reverse transcriptase inhibitor that is used in the treatment of human immunodeficiency virus (HIV) infection in children younger than 3 years old. Identifying genetic predictors of NVP pharmacokinetics (PK) in young children is important because inter-individual variability in NVP concentrations contributes to variable treatment response and the information may be used to individualize dosing decisions. We examined the relationship between genetic variations in relevant drug disposition genes and NVP PK parameters in Ghanaian children living with HIV eligible to initiate NVP-based antiretroviral therapy. Participants received NVP plus zidovudine and lamivudine or abacavir and lamivudine twice daily, and those with tuberculosis (TB) coinfection received concurrent anti-TB therapy with NVP. Pharmacokinetic sampling was performed after at least 4 weeks of antiretroviral therapy. Nevirapine minimum concentration (Cmin), area under the concentration-time curve from time 0 to 12 h (AUC0-12h), and apparent clearance (CL/F) were calculated using non-compartmental analysis using Phoenix v8.0 software. Genotyping for CYP2B6, CYP2A6, CYP3A5, ABCB1, NR1I2, and NR1I3 single nucleotide polymorphism (SNPs) was performed by TaqMan® allelic discrimination method. The median (range) NVP dose received was 10 (7-14) mg/kg. Of the 53 participants, the median (range) Cmin was 3.3 (0.0-14.0) mg/L and AUC0-12h was 56.0 (16.7-202.6) mg.hr/L. Using step-wise regression, CYP2B6 rs3745274 and NR1I2 rs6785049 SNPs were independent as well as joint predictors of NVP AUC0-12h, Cmin, and CL/F. We concluded that genotyping for CYP2B6 rs3745274, and the NR1I2 rs6785049 G > A SNP (which encodes the transcriptional factor, pregnane X receptor), could improve prediction of NVP PK for individualized therapy.

Pharmacokinetics of Efavirenz 600 mg Once Daily During Pregnancy and Post Partum in Ghanaian Women Living With HIV.

PURPOSE: The updated World Health Organization guidelines recommend efavirenz (EFV) 400 mg as the preferred alternate first-line antiretroviral therapy to dolutegravir, with EFV 600 mg recommended only in special situations. We examined the pharmacokinetic (PK) properties of EFV 600 mg/d during pregnancy and post partum to inform EFV dosing decisions in pregnant women. METHODS: Ghanaian pregnant women with HIV infection initiating tenofovir disoproxil fumarate 300 mg/lamivudine 300 mg/EFV 600 mg fixed-dose combination tablet once daily were enrolled. Efavirenz concentrations were measured at 4 weeks of antiretroviral therapy initiation during pregnancy and 6 weeks post partum using validated LC-MS/MS assays. Efavirenz PK parameters were calculated using noncompartmental analysis, and within-group parameters between the 2 periods were compared. FINDINGS: Of 25 enrolled women, 19 completed PK sampling during pregnancy and post partum. The Cmax, Cmin, AUC0-24h, and CL/F for EFV during pregnancy were similar to values at 6 weeks post partum. The pregnancy/postpartum geometric mean ratios for EFV Cmax, Cmin, AUC0-24, and CL/F were 1.10 (95% CI, 0.93-1.31), 0.88 (95% CI, 0.67-1.17), 0.84 (95% CI, 0.71-0.98), and 1.20 (95% CI, 1.02-1.40), respectively. Viral load suppression (HIV RNA <200 copies/mL) was achieved in 16 of 17 participants (94%) by the time of delivery. There was 1 maternal-to-child transmission. IMPLICATIONS: We found that the PK parameters of EFV 600 mg once daily during pregnancy were similar to those in the postpartum period. Our findings suggest that EFV dose adjustment during pregnancy is not necessary in our study population.

High mortality during tuberculosis retreatment at a Ghanaian tertiary center: a retrospective cohort study.

INTRODUCTION: High mortality among individuals receiving retreatment for tuberculosis (RT-TB) persists, although reasons for these poor outcomes remain unclear. METHODS: We retrospectively reviewed 394 RT-TB patients diagnosed between January 2010 and June 2016 in Accra, Ghana. RESULTS: Of RT-TB patients, 161 (40.9%) were treated empirically (negative/absent smear, culture or Xpert), of whom 30.4% (49/161) had only extrapulmonary TB signs or symptoms. Mortality during treatment was 19.4%; 15-day mortality was 10.8%. In multivariable proportional hazards regression, living with HIV (aHR=2.69 [95 CI: 1.51, 4.80], p<0.01) and previous loss-to-follow up (aHR=8.27 (95 CI: 1.10, 62.25), p=0.04) were associated with mortality, while drug susceptibility testing (DST, aHR=0.36 (95 CI: 0.13, 1.01), p=0.052) was protective. Isoniazid resistance was observed in 40% (23/58 tested) and rifampin resistance in 19.1% (12/63 tested). CONCLUSION: High rates of extrapulmonary TB and smear/culture negative disease highlight the barriers to achieving DST-driven RT-TB regimens and the need for improved diagnostics. Our finding of poly-drug resistance in rifampin-susceptible cases supports access to comprehensive first line DST. Additionally, interventions to reduce mortality, especially in HIV co-infected RT-TB patients, are urgently needed.

Effect of HIV infection on TB treatment outcomes and time to mortality in two urban hospitals in Ghana-a retrospective cohort study.

INTRODUCTION: Tuberculosis (TB) is currently causing more deaths than Human Immunodeficiency Virus (HIV) globally. Ghana as one of the 30 high burden TB/HIV countries has a high annual TB case-fatality rate of 10%. The study sought to assess the effect of HIV infection on TB treatment outcomes and assess the time to mortality after treatment onset. METHODS: We conducted a review of treatment files of TB patients who were treated from January 2013 to December 2015 in two urban hospitals in the Accra Metropolis. Modified Poisson regression analysis was used to measure the association between HIV infection and TB treatment outcomes. Kaplan-Meier survival estimates were used to plot survival curves. RESULTS: Seventy-seven percent (83/107) of HIV infected individuals had successful treatment, compared to 91.2% (382/419) treatment success among HIV non-infected individuals. The proportion of HIV-positive individuals who died was 21.5% (23/107) whilst that of HIV-negative individuals was 5.5% (23/419). Being HIV-positive increased the risk of adverse outcome relative to successful outcome by a factor of 2.89(95% CI 1.76-4.74). The total number of deaths recorded within the treatment period was 46; of which 29(63%) occurred within the first two months of TB treatment. The highest mortality rate observed was among HIV infected persons (38.6/1000 person months). Of the 107 TB/HIV co-infected patients, 4(3.7%) initiated ART during TB treatment. CONCLUSION: The uptake of ART in co-infected individuals in this study was very low. Measures should be put in place to improve ART coverage among persons with TB/HIV co-infection to help reduce mortality.

Effect of First-Line Antituberculosis Therapy on Nevirapine Pharmacokinetics in Children Younger than Three Years Old.

Nevirapine-based antiretroviral therapy (ART) is one of the limited options in HIV-infected children younger than 3 years old (young children) with tuberculosis (TB) coinfection. To date, there are insufficient data to recommend nevirapine-based therapy during first-line antituberculosis (anti-TB) therapy in young children. We compared nevirapine pharmacokinetics (PK) in HIV-infected young children with and without TB coinfection. In the coinfected group, nevirapine PK was evaluated while on anti-TB therapy and after completing an anti-TB therapy regimen. Of 53 participants, 23 (43%) had TB-HIV coinfection. While the mean difference in nevirapine PK parameters between the two groups was not significant (P > 0.05), 14/23 (61%) of the children with TB-HIV coinfection and 9/30 (30%) with HIV infection had a nevirapine minimum concentration (Cmin) below the proposed target of 3.0 mg/liter (P = 0.03). In multivariate analysis, anti-TB therapy and the CYP2B6 516G>T genotype were joint predictors of nevirapine PK parameters. Differences in nevirapine PK parameters between the two groups were significant in children with CYP2B6 516GG but not the GT or TT genotype. Among 14 TB-HIV-coinfected participants with paired data, the geometric mean Cmin and area under the drug concentration-time curve from time zero to 12 h (AUC0-12) were about 34% lower when patients were taking anti-TB therapy, while the nevirapine apparent oral clearance (CL/F) was about 45% higher. While the induction effect of anti-TB therapy on nevirapine PK in our study was modest, the CYP2B6 genotype-dependent variability in the TB drug regimen effect would complicate any dose adjustment strategy in young children with TB-HIV coinfection. Alternate ART regimens that are more compatible with TB treatment in this age group are needed. (This study has been registered at ClinicalTrials.gov under identifier NCT01699633.).

Brief Report: Relationship Between ABCC4 SNPs and Hepatitis B Virus Suppression During Tenofovir-Containing Antiretroviral Therapy in Patients With HIV/HBV Coinfection.

BACKGROUND: Incomplete hepatitis B virus (HBV) suppression during antiretroviral therapy (ART) in HIV and HBV coinfected patients is common, but underlying factors are not fully elucidated. We hypothesize that genetic factors that influence nucleoside analog pharmacokinetics will affect HBV treatment response. METHODS: HIV/HBV coinfected patients on tenofovir disoproxil fumarate/lamivudine (TDF/3TC)-containing ART were enrolled. Selected ABCC4 single nucleotide polymorphisms (SNPs) with known effects on nucleoside pharmacokinetics were genotyped using TaqMan assays. Relationship between ABCC4 SNPs and unsuppressed HBV DNA (HBV DNA ≥20 IU/mL) were examined. RESULTS: Of the 50 participants on TDF/3TC-containing ART for a median (range) of 1.5 (1-7.4) years, 20 (40%) had unsuppressed HBV DNA. Participants with unsuppressed compared with those with suppressed HBV DNA were more likely to have negative HBe antibody, lower body mass index, and lower CD4 count at enrollment. Carriers of ABCC4 rs11568695 (G3724A) variant allele were more likely than noncarriers to have unsuppressed HBV (61.1% vs. 29.0%, P = 0.038). Among 36 patients with suppressed HIV RNA (presumed good ART adherence), ABCC4 rs11568695 variant carriers were more likely than noncarriers to have unsuppressed HBV (58.8% vs. 20.0% P = 0.021). Logistic regression analysis that included genetic and nongenetic factors identified ABCC4 rs11568695 variant allele, body mass index, and male sex as predictors of unsuppressed HBV DNA. CONCLUSIONS: We identified a novel association between ABCC4 rs11568695 SNP and poor HBV treatment response. If confirmed in further studies, ABCC4 genotyping could be used to identify individuals who may need intensified HBV therapy.

Identification of hepatitis B virus genotype A/E recombinants in Ghana.

Hepatitis B virus (HBV) exhibits a high degree of heterogeneity with at least 10 genotypes (A-J) identified to date. Intergenotypic recombination is relatively common. Previously, we investigated HBV drug resistance in HIV/HBV co-infected individuals in Ghana. After identifying multiple circulating genotypes and a novel D/E recombinant, we sought to determine if additional individuals were also infected with recombinant HBV. Partial genome sequences from three individuals were initially identified as genotype A4. Full-length HBV genomes were obtained using rolling circle amplification followed by PCR and shown to cluster with known A/E recombinant viruses. Similar recombination breakpoints were observed in these three individuals suggesting local spread of this novel recombinant HBV in Ghana.