Dose finding study for on-demand HIV pre-exposure prophylaxis for insertive sex in sub-Saharan Africa: results from the CHAPS open label randomised controlled trial.

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-1BaL challenge. Secondary outcomes included peripheral blood mononuclear cell (PBMC) p24 concentration, and drug concentrations in foreskin tissue, PBMCs, plasma and foreskin CD4+/CD4-cells. In the control arm, post-exposure prophylaxis (PEP) activity of non-formulated tenofovir-emtricitabine (TFV-FTC) or TAF-FTC was assessed with ex vivo dosing 1, 24, 48 or 72 h post-HIV-1 challenge. FINDINGS: 144 participants were analysed. PrEP with F/TDF or F/TAF prevented ex vivo infection of foreskins and PBMCs both 5 and 21 h after PrEP dosing. There was no difference between F/TDF and F/TAF (p24day15 geometric mean ratio 1.06, 95% confidence interval: 0.65-1.74). Additional ex vivo dosing did not further increase inhibition. In the control arm, PEP ex vivo dosing was effective up to 48 post-exposure diminishing thereafter, with TAF-FTC showing prolonged protection compared to TFV-FTC. Participants receiving F/TAF had higher TFV-DP concentrations in foreskin tissue and PBMCs compared with F/TDF, irrespective of dose and sampling interval; but F/TAF did not confer preferential TFV-DP distribution into foreskin HIV target cells. FTC-TP concentrations with both drug regimens were equivalent and ∼1 log higher than TFV-DP in foreskin. INTERPRETATION: A double dose of either F/TDF or F/TAF given once either 5 or 21 h before ex vivo HIV-challenge provided protection across foreskin tissue. Further clinical evaluation of pre-coital PrEP for insertive sex is warranted. FUNDING: EDCTP2, Gilead Sciences, Vetenskapsrådet.

Development and validation of an LC-MS/MS method for quantification of favipiravir in human plasma.

Favipiravir (FVP) is a broad-spectrum antiviral that selectively inhibits viral RNA-dependent RNA polymerase, first trialled for the treatment of influenza infection. It has been shown to be effective against a number of RNA virus families including arenaviruses, flaviviruses and enteroviruses. Most recently, FVP has been investigated as a potential therapeutic for severe acute respiratory syndrome coronavirus 2 infection. A liquid chromatography tandem mass spectrometry method for the quantification of FVP in human plasma has been developed and validated for use in clinical trials investigating favipiravir as treatment for coronavirus disease-2019. Samples were extracted by protein precipitation using acetonitrile, using 13C, 15N- Favipiravir as internal standard. Elution was performed on a Synergi Polar-RP 150 × 2.1 mm 4 µm column using a gradient mobile phase programme consisting of 0.2% formic acid in water and 0.2% formic acid in methanol. The assay was validated over the range 500-50,000 ng/mL; this method was found to be precise and accurate and recovery of FVP from the matrix was high. Stability experiments confirmed and expanded on the known stability of FVP, including under heat treatment and for a period of 10 months at - 80 °C.

Pharmacokinetics of ß-d-N4-Hydroxycytidine, the Parent Nucleoside of Prodrug Molnupiravir, in Nonplasma Compartments of Patients With Severe Acute Respiratory Syndrome Coronavirus 2 Infection.

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 < .0001). Clinical Trials Registration. NCT04746183.

Evidence of HIV pre-exposure or post-exposure prophylaxis (PrEP/PEP) among blood donors: a pilot study, England June 2018 to July 2019.

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. RESULTS: We found evidence of pre-exposure or post-exposure prophylaxis (PrEP/PEP) use in three male blood donors confirmed positive for syphilis (3 out of 46 screened, 6.5%). Two were estimated to have taken PrEP/PEP within a day of donating, and the third within 2 days. Two were new donors, whereas one had donated previously but acquired syphilis infection after his last donation. CONCLUSIONS: Our findings indicate that a small proportion of blood donors have not been disclosing PrEP/PEP use and therefore donating in non-compliance to donor eligibility criteria.

Total and Unbound Doravirine Concentrations and Viral Suppression in CSF.

We determined total and unbound concentrations of doravirine (DOR) in cerebrospinal fluid and blood plasma. Total and unbound DOR concentrations in cerebrospinal fluid exceeded the half-maximal effective concentration against wild-type virus (5.1 ng/mL) in all patients, suggesting that DOR may contribute to inhibit viral replication in this compartment.

Cerebral function parameters in people with HIV switching integrase inhibitors: a randomized controlled trial.

Background: Different 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).Methods: 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. Pharmacodynamic parameters assessed included cognitive function (z-score of 7 domains), patient-reported outcome measures (PROMs; PHQ-9 and Beck's depression questionnaires), cerebral metabolite ratios measured by proton magnetic resonance spectroscopy (H1-MRS) and plasma and cerebrospinal fluid (CSF) HIV RNA. Pharmacokinetic parameters were also assessed in plasma and CSF. Changes and factors associated with changes in pharmacodynamics parameters were assessed.Results:In 20 subjects (19 male, 14 white ethnicity, median age 43 years (IQR: 11.5) and CD4 + count 717 (SD: 298) cells/µL), over 120 days there were no statistically significant changes in cognitive function [mean z-score difference (95%CI) -0.004 (-0.38/0.37); p = 0.98], PROMs [PHQ-9 median score change: 0 in control arm, -0.5 switch arm (p = 0.57); Beck's depression questionnaire: -1.5 control arm, -1.0 switch arm (p = 0.38)], nor cerebral metabolite ratios between study arms. CSF HIV RNA was <5 copies/mL at baseline and day 120 in all subjects. Geometric mean pre-dose CSF dolutegravir concentration was 7.6 ng/mL (95% CI: 5.2-11.1).Conclusions:Switching integrase inhibitor in virologically suppressed PWH without overt neuropsychiatric symptoms resulted in no significant changes in an extensive panel of CNS pharmacodynamics parameters.

The development and validation of a novel LC-MS/MS method for the simultaneous quantification of Molnupiravir and its metabolite ß-d-N4-hydroxycytidine in human plasma and saliva.

In light of the recent global pandemic, Molnupiravir (MPV) or EIDD-2801, developed for the treatment of patients with uncomplicated influenza, is now being trialled for the treatment of infections caused by highly pathogenic coronaviruses, including COVID-19. A sensitive LC-MS/MS method was developed and validated for the simultaneous quantification of MPV and its metabolite ß-d-N4-hydroxycytidine (NHC) in human plasma and saliva. The analytes were extracted from the matrices by protein precipitation using acetonitrile. This was followed by drying and subsequently injecting the reconstituted solutions onto the column. Chromatographic separation was achieved using a polar Atlantis C18 column with gradient elution of 1 mM Ammonium acetate in water (pH4.3) and 1 mM Ammonium acetate in acetonitrile. Analyte detection was conducted in negative ionisation mode using SRM. Analysis was performed using stable isotopically labelled (SIL) internal standards (IS). The m/z transitions were: MPV (328.1→126.0), NHC (258.0→125.9) and MPV-SIL (331.0→129.0), NHC-SIL (260.9→128.9). Validation was over a linear range of 2.5-5000 ng/ml for both plasma and saliva. Across four different concentrations, precision and accuracy (intra- and inter-day) were 15%; and recovery of both analytes from plasma and saliva was between 95% and 100% and 65-86% respectively. Clinical pharmacokinetic studies are underway utilising this method for determination of MPV and its metabolite in patients with COVID-19 infection.

Pharmacokinetic/pharmacodynamic investigation of raltegravir with or without lamivudine in the context of HIV-1 pre-exposure prophylaxis (PrEP).

BACKGROUND: 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. Ex vivo infectivity was compared with baseline. The trial has been registered in https://clinicaltrials.gov/ with the identifier NCT03205566. RESULTS: Steady state for both drugs was reached by day 4. Dosing with raltegravir alone provided modest ex vivo HIV protection with higher drug levels in rectal tissue and vaginal tissue than in plasma on and off PrEP. Off PrEP, plasma and vaginal concentrations declined rapidly, while persisting in the rectum. On PrEP, the highest lamivudine concentrations were in the rectum, followed by vaginal tissue then plasma. Lamivudine washout was rapid in plasma, while persisting in the rectum and vagina. Raltegravir/lamivudine increased ex vivo protection on and off PrEP compared with raltegravir alone, reaching maximum protection at day 2 in rectal tissue and at day 8 in vaginal tissue. CONCLUSIONS: Raltegravir 400 mg+lamivudine 150 mg showed high levels of ex vivo HIV protection, associated with high drug concentrations persisting after discontinuation in vaginal and rectal compartments, supporting further investigation of these agents for PrEP.

Total and Unbound Bictegravir Concentrations and Viral Suppression in Cerebrospinal Fluid of Human Immunodeficiency Virus-Infected Patients (Spanish HIV/AIDS Research Network, PreEC/RIS 56).

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], 1237.2-2586.7) and 6.9 (IQR, 4.8-10.9), respectively. Median unbound BIC concentration was 2.48 ng/mL (IQR, 1.6-3.7). Total and unbound BIC CSF concentrations were above the half-maximal effective concentration value in all patients, and all subjects had human immunodeficiency virus viral suppression in plasma and CSF. Bictegravir may contribute to inhibit viral replication in this compartment.

Pharmacokinetics (PK) of ethinylestradiol/levonorgestrel co-administered with atazanavir/cobicistat.

Background and objectives: Access 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.Methods: 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. Each group underwent intensive PK sampling on days 14, 35, and 56. EE/LNG and ATV/COBI concentrations were measured using validated LC-MS/MS methods.Results: Of 14 healthy female volunteers screened, 11 attended baseline and six completed all PK phases (five withdrew secondary to side effects). Paired data were available for analysis in six subjects for EE/LNG and eight for ATV/COBI. Geometric mean ratios (GMR, with versus without ATV/COBI) and 90% confidence intervals (CI) for LNG Cmax, AUC0-24, C24 were 0.83 (0.68-1.02), 0.92 (0.71-1.18), 1.01 (0.73-1.38). GMR and 90% CI for EE Cmax, AUC0-24, C24 were 1.05 (0.92-1.19), 1.01 (0.83-1.22), 0.75 (0.60-0.93). No grade 3 or 4 adverse events or laboratory abnormalities were observed in the women who completed the study.Conclusions: Our findings showed no significant changes in LNG concentrations and a 25% decrease in EE C24 when EE/LNG was co-administered with ATV/COBI.

Validation and clinical application of a novel LC-MS method for quantification of dolutegravir in breast milk.

Aim: A 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. Results/methodology: Sample extraction was by liquid-liquid extraction using tert-butyl methy-ether, with DTG-d5 as an internal standard. DTG was eluted on a reverse phase C18 Waters XBridge (3.5 µm: 2.1 × 50 mm) column using a gradient mobile phase consisting of 0.1% formic acid in deionised water or methanol. The assay was validated over a calibration range of 10-4000 ng/ml. Conclusion: Stability, inter and intra-assay variability were acceptable according to FDA and EMA bioanalytical method guidelines. The assay is robust, accurate, precise and can be reliably applied for analysis of clinical samples in trials from low resource settings.

Development, validation and utilization of a highly sensitive LC-MS/MS method for quantification of levonorgestrel released from a subdermal implant in human plasma.

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. Liquid-liquid extraction was utilized with a sample volume of 500 µL to extract levonorgestrel from plasma. Chromatographic separation of LNG was achieved with a Fortis™ C18 (3 µm: 100 mm × 2.1 mm) reverse phase analytical column. The mobile phases consisted of de-ionized water plus 0.1% NH4OH (100:0.1%, v/v) (A), and methanol plus 0.1% NH4OH (100:0.1%, v/v) (B) delivered as a gradient at a flow rate of 400 µL/min. Detection of LNG and internal standard (D-(-)-norgestrel-d7) was achieved using positive polarity mode monitoring at 313.2-245.2 amu and 320.1-251.2 amu, respectively. The assay was linear over the calibration range of 49.6 to 1500 pg/mL. This method was used to quantify plasma LNG released by subdermal implant in support of a drug interaction study among women with HIV receiving efavirenz- or nevirapine-based antiretroviral therapy.

The development and application of a novel LC-MS/MS method for the measurement of Dolutegravir, Elvitegravir and Cobicistat in human plasma.

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. A liquid- liquid extraction was used as a sample preparation technique using 100µL of plasma. The method was validated from 10 to 4000ng/mL for Dolutegravir, Elvitegravir and Cobicistat. Chromatography was performed on XBridge C18 2.1mm×50mm column, using an 80:20 methanol/water mobile phase containing 0.1% formic acid on a gradient program. This method was successfully applied for ongoing clinical trials.

A Validated Method for Quantification of Dolutegravir Using Ultra Performance Liquid Chromatography Coupled With UV Detection.

BACKGROUND: 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. METHODS: A simple and rapid protein precipitation method was used for analyte extraction from 100 µL plasma. The separation was achieved on a C8 reverse-phase analytical column using a gradient elution with 50 mmol/L formic acid and 50 mmol/L ammonium acetate in water (mobile phase A), and 100% acetonitrile (mobile phase B) and at a flow rate of 0.3 mL/min and a total run time of 10 minutes. The detector wavelength was set at 258 nm. RESULTS: The linearity of the calibration curve (r > 0.9999, n = 6) was validated over a concentration range of 0.25-10 mcg/mL. Intra-assay variability ranged from 3.3% to 6.1% and inter-assay variability ranged from 4.5% to 5.7%. The overall accuracy ranged from 90.7% to 97.7% for the 3 different concentrations of quality control samples. Recovery efficiency of extraction ranged from 94.3%-100%. This method is highly selective with no interferences from commonly concomitant antiretroviral drugs or endogenous metabolites. CONCLUSIONS: The described method is simple, robust, selective, accurate, precise, and cost-effective. Thus, this assay can be readily transferred and implemented in clinical settings and used for pharmacokinetic studies and therapeutic drug monitoring programs.

Efavirenz- but not nevirapine-based antiretroviral therapy decreases exposure to the levonorgestrel released from a sub-dermal contraceptive implant.

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. The two-rod (75 mg/rod) LNG sub-dermal implant was inserted at study enrolment. LNG sampling was obtained pre-implant and at weeks 1, 4, 12 and 24 post-insertion. LNG concentrations were analyzed using a validated LC-MS/MS method, with an assay calibration range of 50-1500 pg/mL. Safety monitoring, including a pregnancy test, was conducted at each study visit. RESULTS: At enrolment, participants had a mean age of 31 years; CD4+ cell counts were similar between the control, NVP and EFV groups (758, 645 and 568 cells/mm(3), respectively; p=0.09); all women in the NVP and EFV groups had an undetectable HIV-RNA. Women in the control group had a higher baseline body weight (73 kg) compared to those in the NVP (63 kg; p=0.03) or EFV groups (60 kg; p<0.01). By linear regression, weight was a significant predictor of LNG concentrations (1 kg increase in weight=5 pg/mL decrease in LNG, p=0.03). LNG concentrations are reported in the table. CONCLUSIONS: Over a 24-week period, LNG concentrations were 40-54% lower in women on EFV-based ART, despite their having a significantly lower body weight, compared to those not on ART. In women on NVP-based ART, LNG concentrations were 32-39% higher than those observed in the control group, a difference partially explained by body weight. These data confirm a significant drug interaction occurs between the LNG implant and EFV, adding to growing concern for reduced contraceptive efficacy with their combined use. In contrast, these data support use of the LNG implant with NVP-based ART.

Quantification of rilpivirine in human plasma, cervicovaginal fluid, rectal fluid and genital/rectal mucosal tissues using liquid chromatography-tandem mass spectrometry.

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 0.5-400 ng/ml. CONCLUSION: Inter- and intra-assay precision and accuracy met the acceptance as per US FDA bioanalytical guidelines. The validated assay has been used for the determination of rilpivirine concentrations in these matrices as part of an exploratory pharmacokinetic study investigating the suitability of a long-acting formulation of rilpivirine for pre-exposure prophylaxis.

Validation of an electrospray ionisation LC-MS/MS method for quantitative analysis of telaprevir and its R-diastereomer.

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%), 100:0.01 (v/v) (mobile phase A) and ACN:MeOH:ammonia (25%), 15:85:0.01 (v/v/v) (mobile phase B). The MS acquisition was performed with selective reaction monitoring mode using the respective [M+H](+) ions, m/z 680.59→322.42 for telaprevir and VRT-127394, and 691.15→110.13 for telaprevir-d11. The assay exhibited a linear dynamic range of 5-5000ng/mL for telaprevir and VRT-127394. Acceptable precision (%RSD<6.5%) and accuracy (94-108%) were obtained for concentrations over the range of the standard curve. A procedure was established to stabilise the plasma to prevent ex vivo interconversion of the isomers.