Tenofovir Alafenamide Plasma Concentrations Are Reduced in Pregnant Women Living With Human Immunodeficiency Virus (HIV): Data From the PANNA Network.

BACKGROUND: Tenofovir alafenamide (TAF), a prodrug of tenofovir (TFV), is included in the majority of the recommended first-line antiretroviral regimens for patients living with human immunodeficiency virus (HIV), but there are limited data on TAF use in pregnant women. We aimed to examine the plasma pharmacokinetics of TAF and TFV in pregnant women from Europe. METHODS: Pregnant women living with HIV were included from treatment centers across Europe, and intensive pharmacokinetic sampling in the third trimester and postpartum was performed. Pharmacokinetic parameters of TAF and TFV were determined with noncompartmental analysis. The proportion of women with a TAF area under the curve (AUClast) below the target of 53.1 ng∗h/mL was determined. Clinical efficacy and safety outcome parameters were reported. RESULTS: In total, 20 pregnant women living with HIV were included. At the third trimester, geometric mean TAF AUClast and Cmax were decreased by 46% and 52%, respectively, compared with postpartum. TFV AUC0-24h, Cmax, and Ctrough decreased by 33%, 30%, and 34%, respectively. The proportion of women with a TAF AUClast < 53.1 ng∗h/mL was 6% at third trimester and 0% postpartum. One out of 20 women had a viral load > 50 copies/mL at third trimester and no mother-to-child transmission occurred. CONCLUSIONS: TAF plasma concentrations were reduced by about half in women living with HIV during third trimester of pregnancy but remained above the predefined efficacy target in the majority of the pregnant women. TFV concentrations were reduced by approximately 30% during third trimester. Despite the observed exposure decrease, high virologic efficacy was observed in this study.

Anticoagulant medication errors in hospitals and primary care: a cross-sectional study.

OBJECTIVE: To assess the proportion of all medication error reports in hospitals and primary care that involved an anticoagulant. Secondary objectives were the anticoagulant involved, phase of the medication process in which the error occurred, causes and consequences of 1000 anticoagulant medication errors. Additional secondary objectives were the total number of anticoagulant medication error reports per month, divided by the total number of medication error reports per month and the proportion of causes of 1000 anticoagulant medication errors (comparing the pre- and post-guideline phase). DESIGN: A cross-sectional study. SETTING: Medication errors reported to the Central Medication incidents Registration reporting system. PARTICIPANTS: Between December 2012 and May 2015, 42 962 medication errors were reported to the CMR. INTERVENTION: N/A. MAIN OUTCOME MEASURE: Proportion of all medication error reports that involved an anticoagulant. Phase of the medication process in which the error occurred, causes and consequences of 1000 anticoagulant medication errors. The total number of anticoagulant medication error reports per month, divided by the total number of medication error reports per month (comparing the pre- and post-guideline phase) and the total number of causes of 1000 anticoagulant medication errors before and after introduction of the LSKA 2.0 guideline. RESULTS: Anticoagulants were involved in 8.3% of the medication error reports. A random selection of 1000 anticoagulant medication error reports revealed that low-molecular weight heparins were most often involved in the error reports (56.2%). Most reports concerned the prescribing phase of the medication process (37.1%) and human factors were the leading cause of medication errors mentioned in the reports (53.4%). Publication of the national guideline on integrated antithrombotic care had no effect on the proportion of anticoagulant medication error reports. Human factors were the leading cause of medication errors before and after publication of the guideline. CONCLUSIONS: Anticoagulant medication errors occurred in 8.3% of all medication errors. Most error reports concerned the prescribing phase of the medication process. Leading cause was human factors. The publication of the guideline had no effect on the proportion of anticoagulant medication errors.

Exploring the Breastfeeding Desires and Decision-Making of Women Living with HIV in the Netherlands: Implications for Perinatal HIV Management in Developed Countries.

Introduction: Guidelines in high-income countries recommend women living with human immunodeficiency virus (HIV) to formula feed their newborns, because the possibility of mother-to-child-transmission of HIV during breastfeeding cannot be ruled out. It is an ongoing debate if the possible transmission risk outweighs the medical, cultural, psychological, and social importance of breastfeeding in women stable on current first-line suppressive antiretroviral regimens. The study aim was to explore breastfeeding desires and decision-making of immigrant and nonimmigrant women living with HIV in the Netherlands. Method: A questionnaire was administered orally or online to 82 women living with HIV in the Netherlands. The breastfeeding desires of the participants were collected as categorical data, and breastfeeding decision-making and willingness to adhere to additional monitoring were collected on a 5-point Likert scale. Categorical data were presented as proportions, and Likert scale data were presented in Likert scale bar plots. Results: Seventy-one percent of the participants expressed a desire to breastfeed in the future. The most important factors influencing decision-making to breastfeed were the chance of transmission of HIV to the infant and the advice by the doctor or nurse practitioner. Of the participants, 42% expressed their interest in breastfeeding with a <1/100 transmission risk. More than half of the participants expressed their interest to breastfeed with additional monitoring. Conclusions: A substantial proportion of the women living with HIV in the Netherlands has a desire to breastfeed, of which the majority are willing to adhere to additional monitoring to do so.

A population pharmacokinetics analysis assessing the exposure of raltegravir once-daily 1200 mg in pregnant women living with HIV.

Once-daily two 600 mg tablets (1200 mg q.d.) raltegravir offers an easier treatment option compared to the twice-daily regimen of one 400 mg tablet. No pharmacokinetic, efficacy, or safety data of the 1200 mg q.d. regimen have been reported in pregnant women to date as it is challenging to collect these clinical data. This study aimed to develop a population pharmacokinetic (PopPK) model to predict the pharmacokinetic profile of raltegravir 1200 mg q.d. in pregnant women and to discuss the expected pharmacodynamic properties of raltegravir 1200 mg q.d. during pregnancy based on previously reported concentration-effect relationships. Data from 11 pharmacokinetic studies were pooled (n = 221). A two-compartment model with first-order elimination and absorption through three sequential transit compartments best described the data. We assessed that the bio-availability of the 600 mg tablets was 21% higher as the 400 mg tablets, and the bio-availability in pregnant women was 49% lower. Monte-Carlo simulations were performed to predict the pharmacokinetic profile of 1200 mg q.d. in pregnant and nonpregnant women. The primary criteria for efficacy were that the lower bound of the 90% confidence interval (CI) of the concentration before next dose administration (Ctrough ) geometric mean ratio (GMR) of simulated pregnant/nonpregnant women had to be greater than 0.75. The simulated raltegravir Ctrough GMR (90% CI) was 0.51 (0.41-0.63), hence not meeting the primary target for efficacy. Clinical data from two pregnant women using 1200 mg q.d. raltegravir showed a similar Ctrough ratio pregnant/nonpregnant. Our pharmacokinetic results support the current recommendation of not using the raltegravir 1200 mg q.d. regimen during pregnancy until more data on the exposure-response relationship becomes available.

Effect of Pregnancy and Concomitant Antiretrovirals on the Pharmacokinetics of Tenofovir in Women With HIV Receiving Tenofovir Disoproxil Fumarate-Based Antiretroviral Therapy Versus Women With HBV Receiving Tenofovir Disoproxil Fumarate Monotherapy.

Tenofovir disoproxil fumarate (TDF) is recommended as part of antiretroviral therapy (ART) for pregnant women with HIV and as monotherapy for pregnant women with hepatitis B virus (HBV) monoinfection at high risk of transmitting infection to their infants. Tenofovir (TFV) plasma exposures are reduced during pregnancy; however, concomitant antiretrovirals and the viral infection itself can also influence TFV pharmacokinetics. Our aim was to compare TFV pharmacokinetics in pregnant women receiving TDF-based ART, with or without a ritonavir-boosted protease inhibitor (r/PI), to pregnant women with HBV receiving TDF monotherapy. Non-r/PI regimens were primarily integrase strand transfer inhibitors or nonnucleoside reverse transcriptase inhibitor-based regimens. Data were combined from a pharmacokinetic study of pregnant women with HIV on ART (PANNA), and a study assessing TFV pharmacokinetics in pregnant women with HBV (iTAP). A total of 196 pregnant women, 59 with HIV (32 receiving r/PIs) and 137 with HBV monoinfection were included. Intraindividual TFV area under the plasma concentration-time curve from time 0 to 24 hours was 25%, 26%, and 21% lower during the third trimester compared to 1 month postpartum in women with HIV using TDF and an r/PI or TDF and non-r/PI and women with HBV receiving TDF monotherapy, respectively. TFV area under the plasma concentration-time curve from time 0 to 24 hours was similar in pregnant women receiving non-r/PI to pregnant women with HBV receiving TDF monotherapy (1.84 vs 1.86 µg • h/mL); however, pregnant women receiving TDF with an r/PI had higher exposures (2.41 µg • h/mL; P < .01). Pregnancy reduces TFV exposure and the relative size was not impacted by concomitant antiretroviral drugs or viral infection, but a drug-drug interaction between TDF and r/PI remains during pregnancy, leading to higher exposures than those on TDF and non-r/PI or TDF monotherapy.

Drug-Drug Interactions with Antiretroviral Drugs in Pregnant Women Living with HIV: Are They Different from Non-Pregnant Individuals?

BACKGROUND AND OBJECTIVE: Although the separate effects of drug-drug interactions and pregnancy on antiretroviral drug pharmacokinetics have been widely studied and described, their combined effect is largely unknown. Physiological changes during pregnancy may change the extent or clinical relevance of a drug-drug interaction in a pregnant woman. This review aims to provide a detailed overview of the mechanisms, magnitude, and clinical significance of antiretroviral drug-drug interactions in pregnant women. METHODS: We performed a literature search and selected studies that compared the magnitude of drug-drug interactions with antiretroviral drugs in pregnant vs non-pregnant women. RESULTS: Forty-eight papers examining drug-drug interactions during pregnancy were selected, of which the majority focused on pharmacokinetic boosting. Other selected studies examined the drug-drug interactions between efavirenz and lumefantrine, efavirenz and tuberculosis drugs, etravirine and tenofovir disoproxil fumarate, atazanavir and tenofovir disoproxil, and mefloquine and nevirapine in pregnant compared to non-pregnant women. The clinical significance of antiretroviral drug-drug interactions changed during pregnancy from a minimal effect to a contra-indication. In almost all cases, the clinical significance of a drug-drug interaction was more relevant in pregnant women, owing to the combined effects of pregnancy-induced physiological changes and drug-drug interactions leading to a lower absolute drug exposure. CONCLUSIONS: Multiple studies show that the clinical relevance of a drug-drug interaction can change during pregnancy. Unfortunately, many potential interactions have not been studied in pregnancy, which may place pregnant women living with human immunodeficiency virus and their newborns at risk.