Use of Tenofovir Alafenamide Fumarate for HIV Pre-Exposure Prophylaxis and Incidence of Hypertension and Initiation of Statins

Integrated PrEP and STI Services for Transgender Women in Uganda: Qualitative Findings from a Randomized Trial

Tenofovir alafenamide fumarate (F/TAF) pre-exposure prophylaxis (PrEP) is understudied in sub-Saharan Africa. The Tandika PrEP study was a randomized trial that evaluated same-day F/TAF initiation, the impact of drug-level feedback on PrEP adherence, and integrated PrEP and sexually transmitted infection (STI) services for HIV-negative transgender women (TGW) in Uganda (NCT04491422). From April 2022-February 2023, a qualitative sub-study of 30 in-depth interviews explored (1) perspectives on same-day initiation of F/TAF PrEP, (2) experiences of urine tenofovir testing and drug-level feedback, and (3) descriptions of self-collection of samples for STI testing. Qualitative data were analyzed using an inductive content analytic approach. Integrated PrEP/STI services were valued by TGW because the convenience of urine testing motivated adherence and allowed for tenofovir and STI detection. (1) Preferred characteristics: F/TAF-based PrEP was easy to take and not readily identifiable as an HIV-related medication, resulting in less stigma than the better-known tenofovir disoproxil fumarate (F/TDF). Weight gain associated with F/TAF use was viewed positively by TGW as a symbol of health and prosperity in African settings. (2) Adherence motivation: PrEP adherence was motivated by a desire not to disappoint healthcare workers; TGW reciprocated adherence support and drug-level feedback by taking PrEP. (3) Facilitating adherence and STI care: Urine testing enhanced STI detection and treatment. Utilization of urine for tenofovir and STI testing motivated the uptake of HIV/STI care, emphasizing the importance of integrated PrEP and STI services. Integrating PrEP/STI services into differentiated delivery models could increase prevention uptake in this vulnerable population.

HIV Pre-Exposure Prophylaxis

Pre-exposure prophylaxis (PrEP) of human immunodeficiency virus (HIV) represents the most significant breakthrough in the HIV prevention field over the past decade. PrEP is an effective strategy in preventing the transmission of HIV across all populations, providing high adherence. The current PrEP options include oral daily and on-demand tenofovir-based regimens, long-acting injections of cabotegravir, and a 1-month dapivirine vaginal ring. As a component of a multifaceted prevention approach, extensive deployment of PrEP holds the promise to significantly reduce the global HIV epidemic. Nonetheless, barriers still exist in terms of uptake, adherence, and persistence, while disparities in PrEP accessibility remain a concern.

HIV-1 infection kinetics, drug resistance, and long-term safety of pre-exposure prophylaxis with emtricitabine plus tenofovir alafenamide (DISCOVER): week 144 open-label extension of a randomised, controlled, phase 3 trial

BACKGROUND

Data characterising the long-term use and safety of emtricitabine plus tenofovir disoproxil fumarate as daily oral pre-exposure prophylaxis (PrEP) are scarce and there are uncertainties regarding the value of routine HIV-1 RNA testing during oral PrEP follow-up.

METHODS

The DISCOVER trial was a randomised, controlled, phase 3 trial in which cisgender men and transgender women aged 18 years and older with a high likelihood of acquiring HIV were recruited from 94 clinics in Europe and North America and randomly assigned to receive either emtricitabine plus tenofovir disoproxil fumarate (200/25 mg) tablets daily, with matched placebo tablets, or emtricitabine plus tenofovir alafenamide (200/300 mg) tablets daily, with matched placebo tablets, for at least 96 weeks. After completion of the trial, participants were offered enrolment in this 48-week open-label extension study of emtricitabine plus tenofovir alafenamide. In participants diagnosed with HIV during the randomised and open-label phases of the study, we characterised HIV-1 test results and measured HIV-1 RNA viral load retrospectively when available. Adherence based on tenofovir diphosphate concentrations in dried blood spots and genotypic resistance were assessed in participants diagnosed with HIV. Safety assessments included adverse events, laboratory parameters, and, in a subset of participants, bone mineral density. HIV-1 incidence in participants initially randomly assigned to receive emtricitabine plus tenofovir alafenamide was estimated using a Poisson distribution. Changes from baseline in safety endpoints were described in participants assigned to received emtricitabine plus tenofovir alafenamide and in those who switched from emtricitabine plus tenofovir disoproxil fumarate during the open-label phase. This trial is registered with ClinicalTrials.gov, NCT02842086, and is ongoing.

FINDINGS

Between Sept 13, 2016, and June 30, 2017, 5399 participants were enrolled and randomly assigned in DISCOVER. 2699 were assigned to receive emtricitabine plus tenofovir disoproxil fumarate and 2700 were assigned to receive emtricitabine plus tenofovir alafenamide, of whom 2693 and 2694, respectively, received at least one dose of study drug. 2115 (79%) assigned to emtricitabine plus tenofovir disoproxil fumarate switched to emtricitabine plus tenofovir alafenamide in the open-label phase, and 2070 (77%) continued with emtricitabine plus tenofovir alafenamide in the open-label phase. As of data cutoff (Dec 10, 2020), after 15 817 person-years of follow-up, 27 new HIV-1 diagnoses were observed across the total study period, with three occurring during the open-label phase. In participants who were initially assigned to emtricitabine plus tenofovir alafenamide, the incidence was 0·13 per 100 person-years (95% CI 0·061-0·23; ten of 2670). Stored plasma samples were available for 23 of 27 participants, including 22 with incident infection. In four (17%) of 23 participants, retrospective testing detected HIV-1 RNA before serological HIV-1 test positivity; one was a suspected baseline infection. Of the three incident cases, all three were non-adherent to PrEP and none developed drug resistance. Among participants taking emtricitabine plus tenofovir alafenamide for up to 144 weeks, markers of glomerular filtration and proximal renal tubule dysfunction (β2-microglobulin to creatinine ratio and retinol-binding protein to creatinine ratio) improved or remained stable at 144 weeks compared with baseline, bone mineral density in hip and lumbar spine increased or remained stable from baseline to week 144 (n=191), cholesterol and glucose concentrations remained stable, and median bodyweight increased by less than 1 kg per year. In participants who switched from emtricitabine plus tenofovir disoproxil fumarate during the open-label phase (2115 [79%] of 2693), markers of glomerular filtration and proximal renal tubule dysfunction improved or remained stable, bone mineral density increased, cholesterol concentrations increased, glucose concentrations were similar, and median bodyweight increased more compared with those who remained on emtricitabine and tenofovir alafenamide.

INTERPRETATION

Routine HIV-1 RNA testing for follow-up of individuals on daily oral PrEP provides modest additional clinical benefit. Long-term use of emtricitabine and tenofovir alafenamide as daily oral PrEP is safe and well tolerated and can be an especially appropriate choice for people with bone or renal morbidities.

FUNDING

Gilead Sciences.

Blood pressure increases are associated with weight gain and not antiretroviral regimen or kidney function: a secondary analysis from the ADVANCE trial in South Africa

INTRODUCTION

Recent evidence has raised questions about whether newer HIV treatment regimens, including dolutegravir (DTG) and tenofovir alafenamide (TAF), are associated with increases in blood pressure (BP).

METHODS

We assessed changes in BP by treatment regimen and evaluated the relative contribution of kidney function and weight gain to these changes among participants in the ADVANCE phase-3 trial clinical trial in South Africa (study dates: January 2017-February 2022). Our primary outcome of interest was a change in systolic BP (SBP) at 96 and 192 weeks, among those not receiving antihypertensive medication. The secondary outcome was treatment-emergent hypertension at these same time points, defined as BP ≥140/90 mmHg on two occasions, or initiation of antihypertensive medication after week 4 among individuals without hypertension at enrolment. We used linear regression to evaluate the relationship between change in estimated glomerular filtration rate (eGFR) and change in SBP; and Poisson regression to evaluate the relationship between change in eGFR and treatment-emergent hypertension at each time point. All models were adjusted for age, sex, treatment group and change in body mass index (BMI).

RESULTS

Over 96 weeks, the average changes in SBP were 1.7 mmHg (95% CI: 0.0-3.4), -0.5 mmHg (95% CI: -2.2 to 1.7) and -2.1 mmHg (95% CI: -3.8 to 0.4) in the TAF/emtricitabine (FTC)/DTG, tenofovir disoproxil fumarate (TDF)/FTC/DTG and TDF/FTC/efavirenz (EFV) groups, respectively. This difference was significant for the TAF/FTC/DTG compared to the TDF/FTC/EFV group (p = 0.002). Over 96 weeks, 18.2% (95% CI: 13.4-22.9), 15.4% (95% CI: 11.0-19.9) and 13.3% (95% CI: 8.9-17.6) of participants developed treatment-emergent hypertension, respectively. In adjusted models, there was no significant relationship between change in eGFR and either outcome. Change in BMI was significantly associated with an increase in SBP, while age was associated with an increased risk of treatment-emergent hypertension. Adjustment for BMI also mitigated the unadjusted relationship between HIV treatment regimen and SBP where present.

CONCLUSIONS

In the ADVANCE cohort, weight gain and age accounted for increases in BP and risk of treatment-emergent hypertension. HIV treatment programmes may need to integrate the management of obesity and hypertension into routine care.

CLINICAL TRIAL NUMBER

NCT03122262.

Rational Design and Characterization of Trispecific Antibodies Targeting the HIV-1 Receptor and Envelope Glycoprotein

Multitudinous broadly neutralizing antibodies (bNAbs) against HIV-1 have been developed as novel antiviral prophylactic and therapeutic agents. Combinations of bNAbs are generally even more effective than when they are applied individually, showing excellent neutralization coverage and limiting the emergence of escape mutants. In this study, we investigated the design and characterization of three trispecific antibodies that allow a single molecule to interact with independent HIV-1 envelope determinants-(1) the host receptor CD4, (2) the host co-receptor CCR5 and (3) distinct domains in the envelope glycoprotein of HIV-1-using an ELISA, an HIV-1 pseudovirus neutralization assay and in vivo antiviral experiments in humanized mice. We found that trispecific bNAbs and monovalent ones all had satisfactory binding activities against the corresponding antigens in the ELISA, exhibited higher potency and breadth than any previously described single bnAb in the HIV-1 pseudovirus neutralization assay and showed an excellent antiviral effect in vivo. The trispecific antibodies simultaneously recognize the host receptor CD4, host co-receptor CCR5 and HIV-1 envelope glycoprotein, which could mean they have promise as prophylactic and therapeutic agents against HIV-1.