Background: The efficacy of on-demand HIV pre-exposure prophylaxis (PrEP) for men in sub-Saharan Africa has not been evaluated, and the on-demand PrEP dosing requirement for insertive sex remains unknown.
Methods: HIV-negative males 13-24 years, requesting voluntary medical male circumcision (VMMC), were enrolled into an open-label randomised controlled trial (NCT03986970), and randomised 1:1:1:1:1:1:1:1:1 to control arm or one of eight arms receiving emtricitabine-tenofovir disoproxil fumarate (F/TDF) or emtricitabine-tenofovir alafenamide (F/TAF) over one or two days, and circumcised 5 or 21 h thereafter. The primary outcome was foreskin p24 concentrations following ex vivo HIV-1 challenge.
Background: HIV-1 pre-exposure prophylaxis (PrEP) has focused predominantly on protective efficacy in receptive sex, with limited research on the dosing requirements for insertive sex. We pre-clinically assessed the ex vivo pharmacokinetic-pharmacodynamic (PK-PD) profile of tenofovir (TFV) and tenofovir alafenamide (TAF) in foreskin tissue.
Methods: Inner and outer foreskin explants were exposed to serial dilutions of TFV or TAF prior to addition of HIV-1 at a high (HVT) or a low viral titer (LVT).
ß-d-N4-hydroxycytidine (NHC), the parent nucleoside of molnupiravir, a COVID-19 antiviral, was quantified at SARS-CoV-2 transmission sites in 12 patients enrolled in AGILE Candidate-Specific Trial-2. Saliva, nasal, and tear NHC concentrations were 3%, 21%, and 22% that of plasma. Saliva and nasal NHC were significantly correlated with plasma (P < .
View Article and Find Full Text PDFDifferent antiretroviral therapies (ARTs) may have differing effects on central nervous system (CNS) function. We assessed CNS pharmacodynamic effects of switching integrase inhibitors in people-with-HIV (PWH). PWH on tenofovir-DF/emtricitabine plus raltegravir 400 mg twice daily with suppressed plasma HIV RNA and without overt neuropsychiatric symptoms were randomly allocated on a 1:2 basis to remain on raltegravir or switch to dolutegravir 50 mg once daily for 120 days.
View Article and Find Full Text PDFBackground: To characterize their potential use in pre-exposure prophylaxis (PrEP) we compared the pharmacokinetics of raltegravir and lamivudine in genital tissue against ex vivo tissue infection with HIV-1.
Methods: Open-label trial of 36 HIV-negative females and males randomized to 7 days raltegravir 400 mg twice daily and 7 days raltegravir 400 mg+lamivudine 150 mg twice daily (after washout), or vice versa. Blood, saliva, rectal fluid, rectal tissue, vaginal fluid and vaginal tissue were sampled at baseline and on and off PrEP during a total of 12 days, for pharmacokinetics and antiviral activity via ex vivo HIV-1BaL challenge.
Objective: Due to increased use of pre-exposure prohylaxis (PrEP) and its potential to affect HIV screening of blood donors, we undertook antiretroviral residual testing among HIV-negative male donors in England.
Methods: Residual plasma samples were obtainnd from 46 male donors confirmed positive for syphilis and 96 donors who were repeat reactive for HIV antibodies in screening but confirmed as HIV-negative by reference testing. These were tested for concentrations of tenofovir and emtricitabine by high-performance liquid chromatograhpy coupled with mass spectrometry.
We determined total and unbound concentrations of bictegravir (BIC) in cerebrospinal fluid (CSF) in 15 asymptomatic, virologically suppressed patients. The median plasma and CSF total BIC concentrations were 1837.1 ng/mL (interquartile range [IQR], 1237.
View Article and Find Full Text PDFAccess to safe and reliable contraception in the context of ARVs is essential. This study aimed to investigate the steady-state pharmacokinetics (PK) of ethinylestradiol/levonorgestrel (EE/LNG) 30/150 μg (Microgynon) and atazanavir/cobicistat (ATV/COBI) 300/150 mg (Evotaz), co-administered in HIV negative female volunteers, and assess its safety and tolerability. This phase 1, open label, 57-day, cross over, PK study randomized participants to one of two groups: (i) group 1 received EE/LNG alone on days 1-21, EE/LNG (21 days) + ATV/COBI (14 days) in the co-administration phase (days 22-42) and ATV/COBI alone on days 43-56; (ii) group 2 followed the same sequence but started with ATV/COBI and concluding with EE/LNG.
View Article and Find Full Text PDFHerbal medication use amongst people living with human immunodeficiency virus (PLWH) is widespread and understudied. This study aimed to evaluate the prevalence of herbal medicine use amongst PLWH and possible contamination with antiretrovirals (ARVs). Countrywide collection of herbal samples sold by street vendors in Nigeria for the following indications: human immunodeficiency virus (HIV), acquired immune deficiency syndrome, fever and general weakness.
View Article and Find Full Text PDFA novel, sensitive and reproducible method for quantification of dolutegravir (DTG) in dried breast milk spots (DBMS) was developed and validated for use in clinical studies. Its application enabled measurement of DTG pharmacokinetics in breastfeeding mothers and their infants. Sample extraction was by liquid-liquid extraction using tert-butyl methy-ether, with DTG-d5 as an internal standard.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
May 2018
Levonorgestrel (LNG) is a synthetic progestin that is available in oral contraceptive tablets, a subdermal implant, and an intrauterine system for contraception. LNG pharmacokinetics are a pivotal determinant of contraceptive efficacy and essential in assessing drug-drug interactions influencing LNG exposure following different routes of LNG administration. A highly sensitive LC-MS/MS method was developed and validated to quantify levonorgestrel in human plasma.
View Article and Find Full Text PDFLong-acting injectable antiretroviral (LA-ARV) drugs with low toxicity profiles and propensity for drug-drug interactions are a goal for future ARV regimens. C34-PEG-Chol is a novel cholesterol tagged LA HIV-fusion-inhibitor (FI). We assessed pre-clinical toxicology and first-in-human administration of C34-PEG-Chol.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
August 2016
Dolutegravir and Elvitegravir belongs to a class of integrase inhibitors which has recently been approved by the FDA for the treatment of HIV-infection. Elvitegravir and its co-administered booster drug, Cobicistat, has shown the potential to be a candidate for a one pill once a day regimen and is currently a component of many clinical trials. A sensitive LC-MS/MS method has been developed and validated for the simultaneous determination of these three drugs in human plasma.
View Article and Find Full Text PDFBackground: Dolutegravir (DTG) is an integrase strand transfer inhibitor, which is a newly approved antiretroviral drug used for the treatment of HIV-infected naive and experienced individuals. Many aspects of DTG pharmacology remain to be studied. Our aim was to develop and fully validate a robust analytical method for the quantification of DTG in plasma using liquid chromatography coupled with UV detection.
View Article and Find Full Text PDFObjectives: The validation and clinical application of an LC-MS/MS method for the quantification of nevirapine in dried blood spots (DBS) and dried breast-milk spots (DBMS) are presented.
Methods: DBS and DBMS were prepared from 50 and 30 μL of nevirapine-spiked whole blood and human breast milk, respectively. Chromatographic separation was achieved on a reverse-phase C18 column with 0.
Introduction: Sub-dermal hormone implants, such as levonorgestrel (LNG), are a safe and desirable form of long-acting contraception, but their use among HIV-positive women on antiretroviral therapy (ART) may be compromised given the potential for a cytochrome P450 3A-mediated drug-drug interaction. Our study aimed to characterize the pharmacokinetics of LNG released from a sub-dermal implant over six months in HIV-positive Ugandan women on nevirapine (NVP)- or efavirenz (EFV)-based ART.
Material And Methods: This non-randomized, parallel group study compared LNG pharmacokinetics between HIV-positive Ugandan women not yet eligible for ART (control group, n=18) and those on stable NVP- (n=20) or EFV- (n=20) based ART.
Background: A sensitive, specific and robust liquid chromatography-tandem mass spectrometry method has been developed and validated for the quantification of rilpivirine in human plasma, genital/rectal biofluids and mucosal tissues.
Methods: Plasma and tissue samples were extracted using protein precipitation (acetonitrile/water; 5:1 v/v), and genital/rectal biofluids absorbed onto ophthalmic swabs were extracted using liquid-liquid extraction (hexane/ethyl acetate; 80:20 v/v). A stable isotope-labeled internal standard ((13)C-d4-RPV) was used, and the assay was validated over a concentration range of 0.
J Chromatogr B Analyt Technol Biomed Life Sci
August 2013
A sensitive high-performance reverse phase liquid chromatography-positive ion electrospray tandem mass spectrometry method was developed and validated for the quantification of telaprevir and its inactive R-diastereomer (VRT-127394) in human plasma. The analytes and the internal standard (telaprevir-d11) were extracted from plasma by liquid-liquid extraction using tert-Butyl methyl ether (TBME). Chromatographic separation was achieved on a reversed-phase Accucore C18 column with a gradient programme consisting of water:ammonia (25%), 100:0.
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