Pharmacokinetics of tenofovir alafenamide, emtricitabine, and dolutegravir in a patient on peritoneal dialysis.

INTRODUCTION: Peritoneal dialysis (PD) is an effective renal replacement modality in people with HIV (PWH) with end-stage kidney disease (ESKD), particularly those with residual kidney function. Data on pharmacokinetics (PK) of antiretrovirals in patients on peritoneal dialysis are limited. METHODS: A single-participant study was performed on a 49-year-old gentleman with ESKD on PD and controlled HIV on once daily dolutegravir (DTG) 50 mg + tenofovir alafenamide (TAF) 25 mg / emtricitabine (FTC) 200 mg. He underwent serial blood plasma, peripheral blood mononuclear cell, and urine PK measurements over 24 h after an observed DTG + FTC/TAF dose. RESULTS: Plasma trough (Cmin) concentrations of TAF, tenofovir (TFV), FTC, and DTG were 0.05, 164, 1,006, and 718 ng/mL, respectively. Intracellular trough concentrations of TFV-DP and FTC-TP were 1142 and 11,201 fmol/million cells, respectively. Compared to published mean trough concentrations in PWH with normal kidney function, observed TFV and FTC trough concentrations were 15.5- and 20-fold higher, while intracellular trough concentrations of TFV-DP and FTC-TP were 2.2-fold and 5.4-fold higher, respectively. TFV and FTC urine levels were 20 times lower than in people with normal GFR. CONCLUSIONS: In a single ESKD PWH on PD, daily TAF was associated with plasma TFV and intracellular TFV-DP trough concentrations 15-fold and 2-fold higher than those of people with uncompromised kidney function, potentially contributing to nephrotoxicity. This suggests that TFV accumulates on PD; thus, daily TAF in PD patients may require dose adjustment or regimen change to optimize treatment, minimize toxicity, and preserve residual kidney function.

Long-acting cabotegravir pharmacokinetics with and without oral lead-in for HIV PrEP.

Long-acting cabotegravir is approved for pre-exposure prophylaxis and combination HIV treatment, both initiated with optional short-term oral lead-in (OLI). We evaluated the impact of OLI on long-acting cabotegravir pharmacokinetics. Cabotegravir plasma concentrations were compared between HIV-positive participants initiating injections with (n = 278) or without (n = 110) OLI in phase III treatment study FLAIR and in HIV-negative participants using OLI (n = 263) in pivotal pre-exposure prophylaxis studies HPTN 083 and HPTN 084. Cabotegravir pharmacokinetic profiles were simulated in three populations (assigned-male-at-birth, 50%-assigned-female-at-birth, and assigned-female-at-birth) under three scenarios: first injection given (A) 1 or (B) 3 days after final OLI dose (OLI-injection gap) or (C) without OLI. The PK objective was 80% of participants achieving 4× in vitro protein-adjusted 90% maximal inhibitory concentration (PA-IC90) and 50% achieving 8× PA-IC90. Observed trough concentrations (Cτ) were similar with and without OLI (P > 0.3). With a 3-day OLI-injection gap, simulated pre-injection Cτ remained above PK objective. Approximately 1-2 weeks after the first injection, simulated PK profiles became nearly identical among all scenarios. Without OLI, it was predicted that 80% of participants achieve 4× PA-IC90 in 1.2, 1.8, and 2.8 days after the first injection in each population, respectively, and 50% achieve 8× PA-IC90 in 1.4, 2.1, and 3.8 days, respectively. Observed long-acting cabotegravir exposure was similar with or without OLI, supporting optional OLI use. Cabotegravir exposure was predicted to remain above PK objective for OLI-injection gaps of ≤3 days and rapidly achieve PK objective after first injection without OLI. Findings are consistent between assigned-male-at-birth and assigned-female-at-birth populations.This study is registered with ClinicalTrials.gov as NCT02720094.

Safety and pharmacokinetics of oral and long-acting injectable cabotegravir or long-acting injectable rilpivirine in virologically suppressed adolescents with HIV (IMPAACT 2017/MOCHA): a phase 1/2, multicentre, open-label, non-comparative, dose-finding study.

BACKGROUND: Combined intramuscular long-acting cabotegravir and long-acting rilpivirine constitute the first long-acting combination antiretroviral therapy (ART) regimen approved for adults with HIV. The goal of the IMPAACT 2017 study (MOCHA [More Options for Children and Adolescents]) was to assess the safety and pharmacokinetics of these drugs in adolescents. METHODS: In this phase 1/2, multicentre, open-label, non-comparative, dose-finding study, virologically suppressed adolescents (aged 12-17 years; weight ≥35 kg; BMI ≤31·5 kg/m2) with HIV-1 on daily oral ART were enrolled at 15 centres in four countries (Botswana, South Africa, Thailand, and the USA). After 4-6 weeks of oral cabotegravir (cohort 1C) or rilpivirine (cohort 1R), participants received intramuscular long-acting cabotegravir or long-acting rilpivirine every 4 weeks or 8 weeks per the adult dosing regimens, while continuing pre-study ART. The primary outcomes were assessments of safety measures, including all adverse events, until week 4 for oral cabotegravir and until week 16 for long-acting cabotegravir and long-acting rilpivirine, and pharmacokinetic measures, including the area under the plasma concentration versus time curve during the dosing interval (AUC0-tau) and drug concentrations, at week 2 for oral dosing of cabotegravir and at week 16 for intramuscular dosing of cabotegravir and rilpivirine. Enrolment into cohort 1C or cohort 1R was based on the participant's pre-study ART, meaning that masking was not done. For pharmacokinetic analyses, blood samples were drawn at weeks 2-4 after oral dosing and weeks 4-16 after intramuscular dosing. Safety outcome measures were summarised using frequencies, percentages, and exact 95% CIs; pharmacokinetic parameters were summarised using descriptive statistics. This trial is registered at ClinicalTrials.gov, NCT03497676, and is closed to enrolment. FINDINGS: Between March 19, 2019, and Nov 25, 2021, 55 participants were enrolled: 30 in cohort 1C and 25 in cohort 1R. At week 16, 28 (97%, 95% CI 82-100) of the 29 dose-evaluable participants in cohort 1C and 21 (91%; 72-99) of the 23 dose-evaluable participants in cohort 1R had reported at least one adverse event, with the most common being injection-site pain (nine [31%] in cohort 1C; nine [39%] in cohort 1R; none were severe). One (4%, 95% CI 0-22) participant in cohort 1R had an adverse event of grade 3 or higher, leading to treatment discontinuation, which was defined as acute rilpivirine-related allergic reaction (self-limiting generalised urticaria) after the first oral dose. No deaths or life-threatening events occurred. In cohort 1C, the week 2 median cabotegravir AUC0-tau was 148·5 (range 37·2-433·1) µg·h/mL. The week 16 median concentrations for the every-4-weeks and every-8-weeks dosing was 3·11 µg/mL (range 1·22-6·19) and 1·15 µg/mL (<0·025-5·29) for cabotegravir and 52·9 ng/mL (31·9-148·0) and 39·1 ng/mL (27·2-81·3) for rilpivirine, respectively. These concentrations were similar to those in adults. INTERPRETATION: Study data support using long-acting cabotegravir or long-acting rilpivirine, given every 4 weeks or 8 weeks, per the adult dosing regimens, in virologically suppressed adolescents aged 12 years and older and weighing at least 35 kg. FUNDING: The National Institutes of Health and ViiV Healthcare.

Phase 1 randomized pharmacokinetic and safety study of a 90-day tenofovir vaginal ring in the United States.

INTRODUCTION: Tenofovir-based oral pre-exposure prophylaxis is currently approved for HIV prevention; however, adherence in women has been low. A vaginal gel containing tenofovir (TFV) demonstrated partial protection to HIV but protection was not confirmed in additional studies. Vaginal rings offer user-controlled long-acting HIV prevention that could overcome adherence and protection challenges. TFV may also help prevent herpes simplex virus type 2 acquisition when delivered intravaginally. We evaluated the pharmacokinetics, safety, adherence and acceptability of a 90-day TFV ring. METHODS: Between January and June 2019, Microbicide Trials Network (MTN)-038 enrolled 49 HIV-negative participants into a phase 1, randomized (2:1) trial comparing a 90-day ring containing 1.4 grams (g) TFV to a placebo ring. TFV concentrations were quantified in plasma, cervicovaginal fluid (CVF), rectal fluid and cervical tissue, and TFV-diphosphate (TFV-DP) in cervical tissue. Used rings were analysed for residual TFV. Safety was assessed by adverse events (AEs); acceptability and adherence by self-report. RESULTS: Mean age was 29.5; 46 identified as cisgender-female and three gender non-conforming. There were no differences in the proportion of participants with grade ≥2 genitourinary AEs in the TFV versus placebo arms (p = 0.41); no grade ≥3 AEs were reported. Geometric mean TFV concentrations increased through day 34 in CVF/rectal fluid and day 59 in plasma, but declined across compartments by day 91. Geometric mean TFV-DP tissue concentrations exceeded the 1000 fmol/mg target through day 56, but fell to 456 fmol/mg at day 91. Among 32 rings returned at the end of the study, 13 had no or low (<0.1 g) residual TFV. Residual TFV did not differ by socio-demographics, sexual activity, Nugent Score or vaginal microbiota. Most participants reported being fully adherent to ring use: 85% and 81% in the TFV and placebo arms, respectively (p = 1.00). A majority of participants reported liking the ring (median 8 on a 10-point Likert scale) and reported a high likelihood of using the ring in the future, if effective (median 9). CONCLUSIONS: The 90-day TFV ring was well-tolerated, acceptable and exceeded target cervical tissue concentrations through day 56, but declined thereafter. Additional studies are needed to characterize the higher release from TFV rings in some participants and the optimal duration of use.

Multiplexed quantification of venlafaxine and metabolites in human plasma by liquid chromatography-tandem mass spectrometry.

BACKGROUND: Venlafaxine (VEN) and its O-demethylated metabolite, O-desmethylvenlafaxine (ODV), are commonly prescribed serotonin-norepinephrine reuptake inhibitors, approved for the treatment of depression and anxiety. Both are metabolized to inactive metabolites via cytochrome P450 enzymes. While previous studies have focused on quantifying VEN and ODV, bioanalytical methods for the simultaneous measurement of all metabolites are needed to fully characterize the pharmacology of VEN and ODV. METHODS: K2EDTA plasma was spiked with VEN, ODV, N-desmethylvenlafaxine (NDV), N,O-didesmethylvenlafaxine (NODDV), and N,N-didesmethylvenlafaxine (NNDDV). Drugs and metabolites were extracted via protein precipitation and quantified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The multiplexed assay was validated in accordance with regulatory recommendations, and evaluated in remnant plasma samples from persons prescribed venlafaxine. RESULTS: The analytical measuring range for venlafaxine and all four metabolites was 5-800 ng/mL. Standard curves were generated via weighted quadratic (NNDDV) or linear (VEN, ODV, NDV, NODDV) regression of calibrators. Inter-assay imprecision was between 1.9-9.3% for all levels of all analytes. Minor matrix effects were observed, and both recovery efficiency and process efficiency were >96% for all analytes. All other assay validation assessments met acceptance criteria. Drug concentrations measured from remnant plasma specimens obtained from patients with current venlafaxine prescriptions (37.5-450 mg/day) yielded NDDV, NDV, and NODDV metabolite concentrations in 6/21, 14/21, and 20/21 samples, respectively. The ratio of active to inactive analytes ranged from 0.74 to 14.5, with a median of 6.39. CONCLUSIONS: An efficient and accurate LC-MS/MS method was developed and validated for the quantification of VEN, ODV, and all three inactive metabolites in plasma. The assay met all acceptance criteria, and may be used in future studies of the pharmacokinetics of these drugs.

Prevalence of SARS-CoV-2 Infection among Children and Adults in 15 US Communities, 2021

During January-August 2021, the Community Prevalence of SARS-CoV-2 Study used time/location sampling to recruit a cross-sectional, population-based cohort to estimate SARS-CoV-2 seroprevalence and nasal swab sample PCR positivity across 15 US communities. Survey-weighted estimates of SARS-CoV-2 infection and vaccine willingness among participants at each site were compared within demographic groups by using linear regression models with inverse variance weighting. Among 22,284 persons >2 months of age and older, median prevalence of infection (prior, active, or both) was 12.9% across sites and similar across age groups. Within each site, average prevalence of infection was 3 percentage points higher for Black than White persons and average vaccine willingness was 10 percentage points lower for Black than White persons and 7 percentage points lower for Black persons than for persons in other racial groups. The higher prevalence of SARS-CoV-2 infection among groups with lower vaccine willingness highlights the disparate effect of COVID-19 and its complications.

Tenofovir Douche as HIV Preexposure Prophylaxis for Receptive Anal Intercourse: Safety, Acceptability, Pharmacokinetics, and Pharmacodynamics (DREAM 01).

BACKGROUND: Despite highly effective HIV preexposure prophylaxis (PrEP) options, no options provide on-demand, nonsystemic, behaviorally congruent PrEP that many desire. A tenofovir-medicated rectal douche before receptive anal intercourse may provide this option. METHODS: Three tenofovir rectal douches-220 mg iso-osmolar product A, 660 mg iso-osmolar product B, and 660 mg hypo-osmolar product C-were studied in 21 HIV-negative men who have sex with men. We sampled blood and colorectal tissue to assess safety, acceptability, pharmacokinetics, and pharmacodynamics. RESULTS: The douches had high acceptability without toxicity. Median plasma tenofovir peak concentrations for all products were several-fold below trough concentrations associated with oral tenofovir disoproxil fumarate (TDF). Median colon tissue mucosal mononuclear cell (MMC) tenofovir-diphosphate concentrations exceeded target concentrations from 1 hour through 3 to 7 days after dosing. For 6-7 days after a single product C dose, MMC tenofovir-diphosphate exceeded concentrations expected with steady-state oral TDF 300 mg on-demand 2-1-1 dosing. Compared to predrug baseline, HIV replication after ex vivo colon tissue HIV challenge demonstrated a concentration-response relationship with 1.9 log10 maximal effect. CONCLUSIONS: All 3 tenofovir douches achieved tissue tenofovir-diphosphate concentrations and colorectal antiviral effect exceeding oral TDF and with lower systemic tenofovir. Tenofovir douches may provide a single-dose, on-demand, behaviorally congruent PrEP option, and warrant continued development. Clinical Trials Registration . NCT02750540.

Assessing Per-Sex-Act HIV-1 Risk Reduction Among Women Using the Dapivirine Vaginal Ring.

BACKGROUND: Confounding introduced by individuals' sexual risk behavior is potentially a significant source of bias in HIV-1 prevention intervention studies. To more completely account for sexual behaviors when assessing the efficacy of the monthly dapivirine ring, a new longer-acting HIV-1 prevention option for women, we estimated per-sex-act risk reduction associated with product use. METHODS: We conducted a secondary analysis of data from MTN-020/ASPIRE, a phase 3, randomized, placebo-controlled efficacy trial of the dapivirine ring that recruited HIV-uninfected, African women aged 18-45 years. With cumulative sex acts as the time scale, we used multivariable Cox regression with inverse probability of censoring weights to estimate HIV-1 risk reduction associated with a rate of dapivirine release indicative of consistent product use. RESULTS: Women in the dapivirine ring group (n = 1187) had an estimated incidence rate of 2.3 (95% confidence interval [CI], 1.8-3.1) HIV-1 acquisition events per 10 000 sex acts versus 3.6 (95% CI, 2.9-4.4) per 10 000 acts in the placebo group (n = 1187). Dapivirine release indicative of consistent ring use was associated with a 63% (95% CI, 33%-80%) per-sex-act HIV-1 risk reduction. CONCLUSIONS: These results support the efficacy of the dapivirine vaginal ring for HIV-1 prevention and help to inform decision-making for women, providers, and policymakers regarding product use. CLINICAL TRIALS REGISTRATION: NCT01617096.

Efficacy and safety of long-acting cabotegravir compared with daily oral tenofovir disoproxil fumarate plus emtricitabine to prevent HIV infection in cisgender men and transgender women who have sex with men 1 year after study unblinding: a secondary analysis of the phase 2b and 3 HPTN 083 randomised controlled trial.

BACKGROUND: Injectable cabotegravir was superior to daily oral tenofovir disoproxil fumarate plus emtricitabine for HIV prevention in two clinical trials. Both trials had the primary aim of establishing the HIV prevention efficacy of long-acting injectable cabotegravir pre-exposure prophylaxis (PrEP) compared with tenofovir disoproxil fumarate plus emtricitabine daily oral PrEP. Long-acting PrEP was associated with diagnostic delays and integrase strand-transfer inhibitor (INSTI) resistance. This report presents findings from the first unblinded year of the HIV Prevention Trials Network (HPTN) 083 study. METHODS: The HPTN 083 randomised controlled trial enrolled HIV-uninfected cisgender men and transgender women at elevated HIV risk who have sex with men, from 43 clinical research sites in Africa, Asia, Latin America, and the USA. Inclusion criteria included: a negative HIV serological test at the screening and study entry, undetectable HIV RNA levels within 14 days of study entry, age 18 years or older, overall good health as determined by clinical and laboratory evaluations, and a creatinine clearance of 60 mL/min or higher. Participants were randomly allocated to receive long-acting injectable cabotegravir or daily oral tenofovir disoproxil fumarate plus emtricitabine PrEP. After study unblinding, participants remained on their original regimen awaiting an extension study. HIV infections were characterised retrospectively at a central laboratory. Here we report the secondary analysis of efficacy and safety for the first unblinded year. The primary outcome was incident HIV infection. Efficacy analyses were done on the modified intention-to-treat population using a Cox regression model. Adverse events were compared across treatment groups and time periods (blinded vs unblinded). This trial is registered with ClinicalTrials.gov, NCT02720094. FINDINGS: Of the 4488 participants who contributed person-time to the blinded analysis, 3290 contributed person-time to the first unblinded year analysis between May 15, 2020, and May 14, 2021. Updated HIV incidence in the blinded phase was 0·41 per 100 person-years for long-acting injectable cabotegravir PrEP and 1·29 per 100 person-years for daily oral tenofovir disoproxil fumarate plus emtricitabine PrEP (hazard ratio [HR] 0·31 [95% CI 0·17-0·58], p=0·0003). HIV incidence in the first unblinded year was 0·82 per 100 person-years for long-acting PrEP and 2·27 per 100 person-years for daily oral PrEP (HR 0·35 [0·18-0·69], p=0·002). Adherence to both study products decreased after study unblinding. Additional infections in the long-acting PrEP group included two with on-time injections; three with one or more delayed injections; two detected with long-acting PrEP reinitiation; and 11 more than 6 months after their last injection. Infection within 6 months of cabotegravir exposure was associated with diagnostic delays and INSTI resistance. Adverse events were generally consistent with previous reports; incident hypertension in the long-acting PrEP group requires further investigation. INTERPRETATION: Long-acting injectable cabotegravir PrEP retained high efficacy for HIV prevention in men and transgender women who have sex with men during the first year of open-label follow-up, with a near-identical HR for HIV risk reduction between long-acting injectable cabotegravir and daily oral tenofovir disoproxil fumarate plus emtricitabine PrEP during the first year after unblinding compared with the blinded period. Extended follow-up further defined the risk period for diagnostic delays and emergence of INSTI resistance. FUNDING: Division of AIDS at the National Institute of Allergy and Infectious Diseases, ViiV Healthcare, and Gilead Sciences.

Efficacy, safety, tolerability, and pharmacokinetics of long-acting injectable cabotegravir for HIV pre-exposure prophylaxis in transgender women: a secondary analysis of the HPTN 083 trial.

BACKGROUND: The HIV Prevention Trials Network (HPTN) 083 trial showed that long-acting injectable cabotegravir was more effective than tenofovir disoproxil fumarate plus emtricitabine in preventing HIV in cisgender men and transgender women who have sex with men. We aimed to characterise the cohort of transgender women included in HPTN 083. METHODS: HPTN 083 is an ongoing, phase 2b/3, randomised, multicentre, double-blind, double-dummy clinical trial done at 43 sites in seven countries (Argentina, Brazil, Peru, the USA, South Africa, Thailand, and Viet Nam). HIV-negative participants were randomly assigned (1:1) to receive injectable cabotegravir or tenofovir disoproxil fumarate plus emtricitabine. The study design and primary outcomes of the blinded phase of HPTN 083 have already been reported. An enrolment minimum of 10% transgender women was set for the trial. Here we characterise the cohort of transgender women enrolled from Dec 6, 2016, to May 14, 2020, when the study was unblinded. We report sociodemographic characteristics, use of gender affirming hormone therapy, and behavioural assessments of the transgender women participants. Laboratory testing and safety evaluations are also reported. The trial is registered at ClinicalTrials.gov, NCT02720094. FINDINGS: HPTN 083 enrolled 570 transgender women (304 tenofovir disoproxil fumarate plus emtricitabine; 266 injectable cabotegravir). Transgender women were primarily from Asia (225 [39%]) and Latin America (205 [36%]); 330 (58%) reported using gender affirming hormone therapy. Intimate partner violence was common (270 [47%] reported emotional abuse and 172 [30%] reported physical abuse) and 323 (57%) reported a history of childhood sexual abuse. 159 (28%) transgender women disagreed that they were at risk for HIV, and 142 (25%) screened positive for depressive symptoms. During study follow-up, incidence of syphilis was 16·25% (95% CI 13·28-19·69), rectal gonorrhoea was 11·66% (9·14-14·66), and chlamydia was 20·61% (17·20-24·49). Frequency of adverse events was similar between the treatment groups. Nine seroconversions occurred among transgender women during the blinded phase of the study (seven in the tenofovir disoproxil fumarate plus emtricitabine group and two in the injectable cabotegravir group); overall incidence was 1·19 per 100 person-years (95% CI 0·54-2·25): 1·80 per 100 person-years (0·73-3·72) in the tenofovir disoproxil fumarate plus emtricitabine group and 0·54 per 100 person-years (0·07-1·95) in the injectable cabotegravir group (hazard ratio 0·34 [95% CI 0·08-1·56]). Cabotegravir concentrations did not differ by gender affirming hormone therapy use. INTERPRETATION: HIV prevention strategies for transgender women cannot be addressed separately from social and structural vulnerabilities. Transgender women were well represented in HPTN 083 and should continue to be prioritised in HIV prevention studies. Our results suggest that injectable cabotegravir is a safe and effective pre-exposure prophylaxis option for transgender women. FUNDING: National Institute of Allergy and Infectious Diseases and ViiV Healthcare.

Clinical trial simulation to evaluate tenofovir disoproxil fumarate/emtricitabine HIV pre-exposure prophylaxis dosing during pregnancy.

Objective: To evaluate upward-adjustment of tenofovir disoproxil fumarate (TDF)/emtricitabine (FTC) pre-exposure prophylaxis (PrEP) dosing during pregnancy in order to maintain target plasma concentrations associated with HIV protection. Design: Population pharmacokinetic (PK) modeling and clinical trial simulation (CTS). Material and methods: We developed population pharmacokinetic models for TFV and FTC using data from the Partners Demonstration Project and a PK study of TDF/FTC among cisgender women by Coleman et al., and performed an in-silico simulation. Pregnancy-trimester was identified as a significant covariate on apparent clearance in the optimized final model. We simulated 1,000 pregnant individuals starting standard daily oral TDF/FTC (300 mg/200 mg) prior to pregnancy. Upon becoming pregnant, simulated patients were split into two study arms: one continuing standard-dose and the other receiving double standard-dose throughout pregnancy. Results: Standard-dose trough TFV concentrations were significantly lower in pregnancy compared to pre-pregnancy, with 34.0%, 43.8%, and 65.1% of trough plasma concentrations below the lower bound of expected trough concentrations presumed to be the protective threshold in the 1st, 2nd, and 3rd trimesters, respectively. By comparison, in the simulated double-dose group, 10.7%, 14.4%, and 27.8% of trough concentrations fell below the estimated protective thresholds in the 1st, 2nd, and 3rd trimesters, respectively. The FTC trough plasma concentration during pregnancy was also lower than pre-pregnancy, with 45.2% of the steady-state trough concentrations below the estimated protective trough concentrations of FTC. In the pregnancy-adjusted double-dose group, 24.1% of trough plasma concentrations were lower than protective levels. Conclusions: Our simulation shows >50% of research participants on standard dosing would have 3rd trimester trough plasma TFV concentrations below levels associated with protection. This simulation provides the quantitative basis for the design of prospective TDF/FTC studies during pregnancy to evaluate the safety and appropriateness of pregnancy-adjusted dosing.

Development and validation of a liquid chromatographic-tandem mass spectrometric assay for the quantification of the direct acting antivirals glecaprevir and pibrentasvir in plasma.

BACKGROUND: Direct acting antiviral (DAA) therapies are effective in the treatment and management of chronic HCV infections. Glecaprevir (GLE) and pibrentasvir (PIB) are pangenotypic DAAs that are delivered alone or as a fixed-dose oral formulation to treat chronic HCV infections with or without cirrhosis. Sensitive and dynamic bioanalytical assays are needed to understand the pharmacology of GLE and PIB. METHODS: Drug free K2EDTA plasma was spiked with GLE, PIB, and their internal standards. Drugs were extracted from plasma via protein precipitation, and subsequently quantified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The method was validated according to regulatory recommendations, and evaluated in remnant plasma samples from individuals prescribed GLE and PIB. RESULTS: The analytical measuring ranges for GLE and PIB were 0.25-2000 ng/mL and 0.25-1000 ng/mL, respectively. The method showed acceptable accuracy and precision for both DAAs. GLE and PIB in plasma were stable following six freeze thaw cycles and at room temperature for up to 67 h. All analytes were stable in whole blood incubated at room temperature for 24 h, and at 40 °C and 100% humidity for 2 h. Negligible percent matrix effects were observed for PIB and PIB-IS across the measuring range of the assay. Significant ion suppression was observed for GLE, with an average matrix effects of 27.9%. However, relative matrix effects were < 6.3% between drug and internal standard, and deemed acceptable. Assay validation assessments in alternative matrices also met acceptance criteria. Both DAAs were successfully measured in remnant plasma samples from individuals administered GLE and PIB. CONCLUSIONS: An LC-MS/MS method for GLE and PIB quantification in plasma has been developed and validated. The assay met acceptable performance criteria and may be used in downstream applications to characterize DAA pharmacology for HCV treatment.

Breakthrough HIV-1 infection in setting of cabotegravir for HIV pre-exposure prophylaxis.

OBJECTIVE: We describe the first case of HIV-1 infection in the setting of long-acting injectable cabotegravir (CAB-LA) for HIV pre-exposure prophylaxis to occur in the real world. DESIGN: Case report. METHODS: Electronic medical records were reviewed to assess patient history and CAB-LA administration details. Plasma fourth-generation HIV-1/2 Ag/Ab combination immunoassay and HIV-1 RNA quantitative PCR were performed at each injection visit. RESULTS: We report a 28-year-old sex-diverse person assigned male at birth who acquired HIV-1 infection 91 days after transitioning from tenofovir alafenamideemtricitabine to CAB-LA despite on-time dosing and appropriate laboratory monitoring. CONCLUSION: This patient's history suggests HIV infection despite on-time and appropriate CAB-LA injections. To our knowledge, this is the first case of CAB-LA pre-exposure prophylaxis failure outside the setting of a clinical trial and highlights diagnostic and management challenges that may occur with such breakthrough infections.

AACC/NKF Guidance Document on Improving Equity in Chronic Kidney Disease Care.

BACKGROUND: Kidney disease (KD) is an important health equity issue with Black, Hispanic, and socioeconomically disadvantaged individuals experiencing a disproportionate disease burden. Prior to 2021, the commonly used estimated glomerular filtration rate (eGFR) equations incorporated coefficients for Black race that conferred higher GFR estimates for Black individuals compared to non-Black individuals of the same sex, age, and blood creatinine concentration. With a recognition that race does not delineate distinct biological categories, a joint task force of the National Kidney Foundation and the American Society of Nephrology recommended the adoption of the CKD-EPI 2021 race-agnostic equations. CONTENT: This document provides guidance on implementation of the CKD-EPI 2021 equations. It describes recommendations for KD biomarker testing, and opportunities for collaboration between clinical laboratories and providers to improve KD detection in high-risk populations. Further, the document provides guidance on the use of cystatin C, and eGFR reporting and interpretation in gender-diverse populations. SUMMARY: Implementation of the CKD-EPI 2021 eGFR equations represents progress toward health equity in the management of KD. Ongoing efforts by multidisciplinary teams, including clinical laboratorians, should focus on improved disease detection in clinically and socially high-risk populations. Routine use of cystatin C is recommended to improve the accuracy of eGFR, particularly in patients whose blood creatinine concentrations are confounded by processes other than glomerular filtration. When managing gender-diverse individuals, eGFR should be calculated and reported with both male and female coefficients. Gender-diverse individuals can benefit from a more holistic management approach, particularly at important clinical decision points.

Extended Analysis of HIV Infection in Cisgender Men and Transgender Women Who Have Sex with Men Receiving Injectable Cabotegravir for HIV Prevention: HPTN 083.

HPTN 083 demonstrated that injectable cabotegravir (CAB) was superior to oral tenofovir disoproxil fumarate-emtricitabine (TDF-FTC) for HIV prevention in cisgender men and transgender women who have sex with men. We previously analyzed 58 infections in the blinded phase of HPTN 083 (16 in the CAB arm and 42 in the TDF-FTC arm). This report describes 52 additional infections that occurred up to 1 year after study unblinding (18 in the CAB arm and 34 in the TDF-FTC arm). Retrospective testing included HIV testing, viral load testing, quantification of study drug concentrations, and drug resistance testing. The new CAB arm infections included 7 with CAB administration within 6 months of the first HIV-positive visit (2 with on-time injections, 3 with ≥1 delayed injection, and 2 who restarted CAB) and 11 with no recent CAB administration. Three cases had integrase strand transfer inhibitor (INSTI) resistance (2 with on-time injections and 1 who restarted CAB). Among 34 CAB infections analyzed to date, diagnosis delays and INSTI resistance were significantly more common in infections with CAB administration within 6 months of the first HIV-positive visit. This report further characterizes HIV infections in persons receiving CAB preexposure prophylaxis and helps define the impact of CAB on the detection of infection and the emergence of INSTI resistance.

Development and validation of a multiplexed assay for the measurement of long-acting hormonal contraceptives in plasma via liquid chromatography-tandem mass spectrometry.

BACKGROUND: Exogenous progestins are an effective tool for hormonal contraception and family planning. Progestins may be delivered as oral pills, intramuscular or subcutaneous injections, vaginal rings, or intrauterine devices. Drug concentrations may vary based on the route and duration of delivery. Measurement of synthetic steroids in blood plasma can aid in determination of product adherence, evaluation of drug-drug interactions, and investigation of unintended pregnancies. METHODS: Drug-free K2EDTA plasma was spiked with the synthetic steroids etonogestrel (ETO), levonorgestrel (LNG), medroxyprogesterone acetate (MPA), and norethisterone (NET). Plasma was combined with isotopically labeled internal standards, and drugs were extracted via liquid-liquid extraction. Samples were then subjected to liquid chromatographic-tandem mass spectrometric (LC-MS/MS) analysis. The method was validated in accordance with regulatory recommendations. The assay was evaluated in a cohort of remnant plasma samples in individuals using one of the aforementioned progestins. RESULTS: The analytical measuring range for ETO, MPA, and NET was 20-10,000 pg/mL; the primary linearity for LNG was 20-20,000 pg/mL. The method showed acceptable precision and accuracy for all progestins. Stability was established for 72 h with room temperature storage and through 3 freeze-thaw cycles. All analytes were stable in whole blood incubated at room temperature for 25 h, and at 40°C and 100% humidity for 2 h. Ion suppression was observed for all analytes spiked in plasma; average ion suppression was 31.6%, 66.6%, 32.1% and 41.2% for ETO, LNG, MPA, and NET, respectively. However, internal standards showed comparable ion suppression, and relative matrix effects were minimal. ETO, LNG, MPA, and NET could also be quantified accurately in K3EDTA plasma and serum. Progestins were successfully measured in remnant samples from individuals using hormonal contraceptives. CONCLUSIONS: A multiplexed LC-MS/MS assay for the quantification of ETO, LNG, MPA, and NET has been developed and validated. The assay met acceptable performance characteristics and may be used in downstream studies to evaluate progestin pharmacology.

High PrEP uptake and objective longitudinal adherence among HIV-exposed women with personal or partner plans for pregnancy in rural Uganda: A cohort study.

BACKGROUND: In Uganda, fertility rates and adult HIV prevalence are high, and many women conceive with partners living with HIV. Pre-exposure prophylaxis (PrEP) reduces HIV acquisition for women and, therefore, infants. We developed the Healthy Families-PrEP intervention to support PrEP use as part of HIV prevention during periconception and pregnancy periods. We conducted a longitudinal cohort study to evaluate oral PrEP use among women participating in the intervention. METHODS AND FINDINGS: We enrolled HIV-negative women with plans for pregnancy with a partner living, or thought to be living, with HIV (2017 to 2020) to evaluate PrEP use among women participating in the Healthy Families-PrEP intervention. Quarterly study visits through 9 months included HIV and pregnancy testing and HIV prevention counseling. PrEP was provided in electronic pillboxes, providing the primary adherence measure ("high" adherence when pillbox was opened ≥80% of days). Enrollment questionnaires assessed factors associated with PrEP use. Plasma tenofovir (TFV) and intraerythrocytic TFV-diphosphate (TFV-DP) concentrations were determined quarterly for women who acquired HIV and a randomly selected subset of those who did not; concentrations TFV ≥40 ng/mL and TFV-DP ≥600 fmol/punch were categorized as "high." Women who became pregnant were initially exited from the cohort by design; from March 2019, women with incident pregnancy remained in the study with quarterly follow-up until pregnancy outcome. Primary outcomes included (1) PrEP uptake (proportion who initiated PrEP); and (2) PrEP adherence (proportion of days with pillbox openings during the first 3 months following PrEP initiation). We used univariable and multivariable-adjusted linear regression to evaluate baseline predictors selected based on our conceptual framework of mean adherence over 3 months. We also assessed mean monthly adherence over 9 months of follow-up and during pregnancy. We enrolled 131 women with mean age 28.7 years (95% CI: 27.8 to 29.5). Ninety-seven (74%) reported a partner with HIV and 79 (60%) reported condomless sex. Most women (N = 118; 90%) initiated PrEP. Mean electronic adherence during the 3 months following initiation was 87% (95% CI: 83%, 90%). No covariates were associated with 3-month pill-taking behavior. Concentrations of plasma TFV and TFV-DP were high among 66% and 47%, 56% and 41%, and 45% and 45% at months 3, 6, and 9, respectively. We observed 53 pregnancies among 131 women (1-year cumulative incidence 53% [95% CI: 43%, 62%]) and 1 HIV-seroconversion in a non-pregnant woman. Mean pillcap adherence for PrEP users with pregnancy follow-up (N = 17) was 98% (95% CI: 97%, 99%). Study design limitations include lack of a control group. CONCLUSIONS: Women in Uganda with PrEP indications and planning for pregnancy chose to use PrEP. By electronic pillcap, most were able to sustain high adherence to daily oral PrEP prior to and during pregnancy. Differences in adherence measures highlight challenges with adherence assessment; serial measures of TFV-DP in whole blood suggest 41% to 47% of women took sufficient periconception PrEP to prevent HIV. These data suggest that women planning for and with pregnancy should be prioritized for PrEP implementation, particularly in settings with high fertility rates and generalized HIV epidemics. Future iterations of this work should compare the outcomes to current standard of care. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03832530 https://clinicaltrials.gov/ct2/show/NCT03832530?term=lynn+matthews&cond=hiv&cntry=UG&draw=2&rank=1.

Development and validation of a liquid chromatographic-tandem mass spectrometric assay for the quantification of cabotegravir and rilpivirine from dried blood spots.

BACKGROUND: Dried blood spots (DBS) have been utilized as a blood plasma alternative for therapeutic drug monitoring and pharmacologic analysis. There are analytical and physiochemical considerations in bridging drug concentrations from plasma to DBS. Recently, the long-acting antiretroviral cabotegravir (CAB) has been approved for HIV prevention, and a co-packaged regimen of long-acting CAB and rilpivirine (RPV) has been approved for HIV treatment. Measurement of these drugs in blood collected as DBS may offer increased capacity and flexibility in translational applications. METHODS: Whole blood was spiked with CAB and RPV and spotted on DBS cards. Following extraction and addition of isotopically labeled internal standards, samples were subjected to liquid chromatographic-tandem mass spectrometric (LC-MS/MS) analysis. The method was validated according to regulatory recommendations, and the assay was evaluated in remnant samples from an HIV prevention trial in which paired DBS and plasma samples were collected. RESULTS: DBS CAB and RPV concentrations were linear from 25 to 20,000 ng/mL and 2-2500 ng/mL, respectively. Precision, accuracy, and matrix effect results were acceptable. DBS RPV demonstrated stability under all tested conditions; DBS CAB showed mean biases of - 23.5% when stored at room temperature for 36 days, and - 18.0% at 40 °C and 100% humidity for two days. DBS measurements for CAB and RPV were an average 54.0% and 14.1% lower, respectively, as compared to paired plasma samples. Derived conversion factors of 1.79 and 1.16 were applied to DBS CAB and RPV measurements, respectively, to estimate plasma concentrations. Estimated plasma CAB and RPV concentrations showed mean biases of 2.2% and 0.6%, respectively. In a CAB clinical trial, application of the conversion factor resulted in agreement between estimated plasma CAB concentrations from DBS and plasma CAB concentrations (y = 1.08x - 79.2, r = 0.932; mean bias of -3.2%; 95% CI: -48.2% to 41.9%). CONCLUSIONS: We developed and validated a novel LC-MS/MS assay for the quantification of CAB and RPV from DBS, and identified conversion factors to estimate plasma concentrations from spotted blood.