Acceptability of the Dapivirine Vaginal Ring and Oral Truvada Among African Users in Late-Stage of Pregnancy

The Microbicide Trials Network 042 study (MTN-042/DELIVER) is a two-arm, randomized, open-label Phase 3b trial that is evaluating the safety, adherence, and acceptability of the monthly ring and daily oral PrEP among HIV-uninfected pregnant people in four African countries. This analysis focuses on acceptability data captured qualitatively from a subset (n = 48) of the 150 people in the first cohort of the trial who were enrolled in late-stage pregnancy at 36 to 38 weeks gestational age and followed until after delivery. Single IDIs were conducted by trained interviewers at each clinic site using a semi-structured guide. Data excerpts of key codes pertaining to acceptability, pregnancy, and maternal health were summarized, reviewed and interpreted by multinational analyst teams. Although the product use period was relatively short, the data suggested several acceptability findings that may directly translate to longer durations of product use in pregnancy. The first was the overarching maternal sentiment that being able to protect both oneself and their baby was highly valued. The second was the importance of counseling support from providers not only because participants used methods that might generate side effects, but because pregnancy itself is a period with its own set of side effects. The third was that, similar to non-pregnant participants in other trials, here study products were generally liked and described as easy to use. Concerns about ring and oral PrEP use could be addressed with provider counseling and support and should form an essential component rollout among pregnant people.

Preexposition Prophylaxis With Truvada (Tenofovir/Emtricitabine) as Potential Cause of Celiac Disease-Like Enteropathy

We present here a case of a 39-year-old patient who presented with celiac-disease-like symptoms and MARSH 3a histology in duodenal biopsies under normal diet. Interestingly, HLA genotyping and celiac-specific serology were negative, primarily leading to exclusion of celiac disease. However, biopsies from a second endoscopy a couple of months later (still under normal diet) showed histologic progression of the disease to MARSH 3b and led to the re-evaluation of the out-of-hospital-obtained histological samples by a pathologist experienced in celiac disease. The second biopsy described previously as MARSH 3b turned out to be non-specific and was therefore re-classified as MARSH 0. After all known causes of duodenal villous atrophy were excluded by a thorough evaluation, a correlation between the first biopsy (MARSH 3a) and Truvada intake could be established. After Truvada discontinuation and under normal diet, normalisation of duodenal mucosa was observed, leading to the assumption that Truvada could lead to celiac-like enteropathy.

Supporting the Art: Medication Adherence Patterns in Persons Prescribed Ingestible Sensor-enabled Oral Pre-Exposure Prophylaxis to Prevent Human Immunodeficiency Virus Infection

BACKGROUND

Timely, accurate adherence data may support oral pre-exposure prophylaxis (PrEP) success and inform prophylaxis choice. We evaluated a Food and Drug Administration (FDA)-approved digital health feedback system (DHFS) with ingestible-sensor-enabled (IS) tenofovir-disoproxil-fumarate plus emtricitabine (Truvada®) in persons starting oral PrEP.

METHODS

Human immunodeficiency virus (HIV)-negative adults were prescribed IS-Truvada® with DHFS for 12 weeks to observe medication taking behavior. Baseline demographics, urine toxicology, and self-report questionnaires were obtained. Positive detection accuracy and adverse events were computed as percentages, with Kaplan Meier Estimate for persistence-of-use. In participants persisting ≥28 days, adherence patterns (taking and timing) were analyzed, and mixed-effects logistic regression modeled characteristics associated with treatment adherence.

RESULTS

Seventy-one participants were enrolled, mean age 37.6 years (range 18-69), 90.1% male, 77.5% White, 33.8% Hispanic, 95.8% housed, and 74.6% employed. Sixty-three participants (88.7%) persisted ≥28 days, generating 4987 observation days, average 79.2 (29-105). Total confirmed doses were 86.2% (95% confidence interval [CI] 82.5, 89.4), decreasing over time, odds ratio (OR) 0.899 (95% CI .876, .923) per week, P < .001; 79.4% (95% CI 66.7%, 87.3%) of participants had ≥80% adherence. Pattern analysis showed days without confirmed doses clustered (P = .003); regular dose timing was higher among participants with ≥80% confirmed doses (0.828, 95% CI .796 to .859) than among those with <80% (0.542, 95% CI95 .405 to .679) P < .001. In multi-predictor models, better adherence was associated with older age, OR 1.060 (95% CI 1.033, 1.091) per year, P < .001; negative vs positive methamphetamine screen, OR 5.051 (95% CI 2.252, 11.494), P < .001.

CONCLUSIONS

DHFS with IS-Truvada® distinguished adherent persons from those potentially at risk of prophylactic failure. Ongoing methamphetamine substance use may impact oral PrEP success.

Role of oral pre-exposure prophylaxis (PrEP) in current and future HIV prevention strategies

Treatment as prevention is expected to have a major role in reducing HIV incidence, but other prevention interventions will also be required to bring the epidemic under control, particularly among key populations. One or more forms of pre-exposure prophylaxis (PrEP) will likely play a critical role. Oral PrEP with emtricitabine-tenofovir (Truvada®) is currently available in the US and some other countries, but uptake has been slow. We review the concerns that have contributed to this slow uptake and discuss current and future research in this critical area of HIV prevention research.

[HIV prophylaxis kits. A concept for emergency treatment in the context of postexposure prophylaxis]

Occupational transmission of HIV among healthcare personnel is rare but has repeatedly been published in the literature. Early initiation of postexposure HIV prophylaxis (HIV-PEP) is crucial to prevent virus transmission. For this reason the need for HIV-PEP has to be evaluated immediately and if necessary, started as soon as possible. This article presents an early intervention program in a university hospital which enables healthcare personnel immediate 24/7/365 access to a HIV-PEP prophylaxis kit following occupational HIV exposure.

Cost effectiveness of darunavir/ritonavir combination antiretroviral therapy for treatment-naive adults with HIV-1 infection in Canada

OBJECTIVE

The AntiRetroviral Therapy with TMC114 ExaMined In naive Subjects (ARTEMIS) clinical trial examined the efficacy and safety of two ritonavir-boosted protease inhibitors (PI/r), darunavir/r 800/100 mg once daily (QD) and lopinavir/r 800/200 mg daily, both used in combination with tenofovir disoproxil fumarate/emtricitabine. This study aimed to assess the cost effectiveness of the darunavir/r regimen compared with the lopinavir/r regimen in treatment-naive adults with HIV-1 infection in Canada.

METHODS

A Markov model with a 3-month cycle time and six CD4 cell-count-based health states (>500, 351-500, 201-500, 101-200, 51-100, and 0-50 cells/mm(3)) followed a cohort of treatment-naive adults with HIV-1 infection through initial darunavir/r or lopinavir/r combination therapy and a common set of subsequent regimens over the course of their remaining lifetimes. Population characteristics and transition probabilities were estimated from the ARTEMIS clinical trial and other trials. Costs (in 2014 Canadian dollars), utilities, and mortality were estimated from Canadian sources and published literature. Costs and health outcomes were discounted at 5% per year. One-way and probabilistic sensitivity analyses were performed, including a simple indirect comparison of the darunavir/r initial regimen with an atazanavir/r-based regimen.

RESULTS

In the base-case lifetime analysis, individuals receiving initial therapy with the darunavir/r regimen experienced 0.25 more quality-adjusted life-years (QALYs) with lower antiretroviral drug costs (-$14,246) and total costs (-$18,402) than individuals receiving the lopinavir/r regimen, indicating that darunavir/r dominated lopinavir/r. In an indirect comparison with an atazanavir/r-based regimen, the darunavir/r regimen remained the dominant choice, but with lower cost savings (-$2,303) and QALY gains (0.02). Results were robust to a wide range of other changes in input parameter values, population characteristics, and modeling assumptions. The probabilistic sensitivity analysis demonstrated that the darunavir/r regimen was cost effective compared with the lopinavir/r regimen in over 86% of simulations for willingness-to-pay thresholds between $0 and $100,000 per QALY gained.

CONCLUSIONS

Darunavir/r 800/100 mg QD may be a cost-effective PI/r component of initial antiretroviral therapy for treatment-naive adults with HIV-1 infection in Canada.

Emtricitabine + tenofovir to prevent HIV transmission. More evaluation needed

Regular condom use is the standard method for preventing HIV transmission during insertive intercourse. Effective treatment of infected individuals also reduces the risk of transmission. However, even when these preventive measures are used correctly, they are not completely reliable. Emtricitabine (a nucleoside) and tenofovir (a nucleotide) are HIV reverse transcriptase inhibitors. The combination of these 2 drugs has been authorised in the United States for the prevention of HIV-1 infection in adults at high risk, in combination with other preventive measures. Clinical evaluation is based mainly on two double-blind placebo-controlled trials. In a trial involving 2499 men or transgender women (born male) who have sex with men, conducted outside Europe, the incidence of infection was lower among patients treated with emtricitabine + tenofovir than with placebo (2.3 versus 4.3 per 100 person-years, p = 0.005). A subgroup analysis showed no added preventive effect of this treatment among condom users. Another trial including 4758 heterosexual couples in which only one partner was infected, conducted in Uganda and Kenya, showed a lower incidence of HIV infection in the emtricitabine + tenofovir group than in the placebo group after one year of treatment (0.50 versus 1.99 per 100 person-years). No statistically significant difference was found between the emtricitabine + tenofovir combination and tenofovir single-agent prophylaxis. Drug prevention showed no added efficacy in this trial among patients who regularly used condoms. Other trials conducted in Africa among heterosexuals favour the preventive efficacy of emtricitabine + tenofovir, except in one trial in which adherence appeared to be very poor. These trials did not identify any previously unknown adverse effects of emtricitabine + tenofovir. Tenofovir can cause kidney failure. Data from a US registry of pregnancies exposed to emtricitabine or tenofovir rule out any major risk of teratogenicity. In situations in which there is a high risk of HIV transmission, daily intake of emtricitabine + tenofovir appears to roughly halve the risk of sexual transmission, without eliminating it completely. In Western Europe, only persons with infected partners and those who engage in risky sexual practices without condoms are at high risk of infection. Long-term assessment of emtricitabine + tenofovir is justified in these situations, despite the mixed results of previous trials.

Prevention of vaginal SHIV transmission in macaques by a coitally-dependent Truvada regimen

Background

Daily pre-exposure prophylaxis (PrEP) with Truvada (a combination of emtricitabine (FTC) and tenofovir (TFV) disoproxil fumarate (TDF)) is a novel HIV prevention strategy recently found to prevent HIV transmission in men who have sex with men and heterosexual couples. We previously showed that a coitally-dependent Truvada regimen protected macaques against rectal SHIV transmission. Here we examined FTC and tenofovir TFV exposure in vaginal tissues after oral dosing and assessed if peri-coital Truvada also protects macaques against vaginal SHIV infection.

Methods

The pharmacokinetic profile of emtricitabine (FTC) and tenofovir (TFV) was evaluated at first dose. FTC and TFV levels were measured in blood plasma, rectal, and vaginal secretions. Intracellular concentrations of FTC-triphosphate (FTC-TP) and TFV-diphosphate (TFV-DP) were measured in PBMCs, rectal tissues, and vaginal tissues. Efficacy of Truvada in preventing vaginal SHIV infection was assessed using a repeat-exposure vaginal SHIV transmission model consisting of weekly exposures to low doses of SHIV162p3. Six pigtail macaques with normal menstrual cycles received Truvada 24 h before and 2 h after each weekly virus exposure and six received placebo. Infection was monitored by serology and PCR amplification of SHIV RNA and DNA.

Results

As in humans, the concentration of FTC was higher than the concentration of TFV in vaginal secretions. Also as in humans, TFV levels in vaginal secretions were lower than in rectal secretions. Intracellular TFV-DP concentrations were also lower in vaginal tissues than in rectal tissues. Despite the low vaginal TFV exposure, all six treated macaques were protected from infection after 18 exposures or 4 full menstrual cycles. In contrast, all 6 control animals were infected.

Conclusions

We modeled a peri-coital regimen with two doses of Truvada and showed that it fully protected macaques from repeated SHIV exposures. Our results open the possibility for simplified PrEP regimens to prevent vaginal HIV transmission in women.

[HIV preexposure prophylaxis]

The pre-exposure chemoprophylaxis (PrEP) is an experimental approach to HIV prevention. The use of antiretroviral drugs has been shown to be effective in prevention HSIV infection in animals. The results from ongoing clinical PrEP trials have demonstrated that antiretrovirals were able to reduce HIV incidence in women and men. The CAPRISA-004 study demonstrated that 1% TDF gel applied intravaginally decreased the risk of HIV infection among heterosexual women in South Africa. The largest global trial iPr Ex conducted in men who have sex with men (MSM), has demonstrated that chemoprophylaxis with daily oral TDF/FTC was 44% effective in protecting against HIV transmission. Following the results of the iPrEx study, the US CDC issued the interim guidance regarding the use of oral PrEP among MSM. Currently more then 20.000 people will be enrolled in studies with oral or topical antiretroviral agents as pre-exposure chemoprophylaxis.

How good is "good enough"? The case for varying standards of evidence according to need for new interventions in HIV prevention

In 2010, randomized controlled trials (RCTs) of two different biomedical strategies to prevent HIV infection had positive findings. However, despite ongoing very high levels of HIV infection in some countries and population groups, it has been made clear by regulatory authorities that the evidence remains insufficient to support either product being made available outside of research contexts in the developing world for at least two years. In addition, prevention trials in endemic areas will continue to test new interventions against placebo. But the judgments of evidentiary standards are never value-neutral. Using the recent trials and their contexts as case studies, we examine the basis for these decisions, which will potentially delay access to scientific innovation to the people who are most urgently in need of it.

A randomised comparison of safety and efficacy of nevirapine vs. atazanavir/ritonavir combined with tenofovir/emtricitabine in treatment-naïve patients

BACKGROUND

We report data from NEWART, a randomised phase 4 clinical trial comparing virologic efficacy and safety of nevirapine (NVP) vs. ritonavir-boosted atazanavir (ATV/r) on a background of tenofovir/emtricitabine (TDF/FTC) in HIV-1-infected treatment-naïve patients. This study enrolled patients according to CD4-based initiation criteria for NVP (<250 cells/mm(3) for women and <400 cells/mm(3) for men), to reduce the likelihood of symptomatic hepatic events. NEWART was designed to support and confirm results from ARTEN, an international trial with similar design and study endpoints.

METHODS

A total of 152 patients were randomised 1 : 1 to open-label NVP 200 mg twice daily or ATV/r (300/100 mg) once daily, plus once daily TDF/FTC (300/200 mg). All participants met CD4(+) guidelines at entry. The primary endpoint for non-inferiority was virologic response prior to and at week 48 (confirmed HIV plasma viral load <50 copies/ml, without rebound or change in ARVs). Safety data, including plasma lipids, were recorded throughout the study.

RESULTS

The primary endpoint was achieved in 46/75 (61.3%) and 50/77 (64.9%) of patients taking NVP and ATV/r, respectively. Frequency of adverse events (AEs) was similar between arms, with 88.0% of NVP-treated patients and 94.8% of ATV/r-treated patients experiencing at least one AE. Nine patients (12%) in each arm experienced an AE that led to discontinuation. At week 48, a significantly greater increase was seen in mean plasma HDL cholesterol (HDL-C) in the NVP arm (9.6 mg/dl) vs. the ATV/r arm (3.5 mg/dl); p = 0.016. Also, total cholesterol (TC):HDL-C ratio on-treatment was -0.38 and -0.02 for the NVP and ATV/r arms, respectively (p = 0.038).

CONCLUSIONS

Efficacy results were consistent with the ARTEN study demonstrating that NVP was non-inferior to ATV/r when taken in combination with TDF/FTC. Rates of AEs were similar between the two arms, whereas HDL-C increased and TC:HDL-C decreased significantly more in patients taking NVP than ATV/r.

T cell chemo-vaccination effects after repeated mucosal SHIV exposures and oral pre-exposure prophylaxis

Pre-exposure prophylaxis (PrEP) with anti-viral drugs is currently in clinical trials for the prevention of HIV infection. Induction of adaptive immune responses to virus exposures during anti-viral drug administration, i.e., a "chemo-vaccination" effect, could contribute to PrEP efficacy. To study possible chemo-vaccination, we monitored humoral and cellular immune responses in nine rhesus macaques undergoing up to 14 weekly, low-dose SHIV(SF162P3) rectal exposures. Six macaques concurrently received PrEP with intermittent, oral Truvada; three were no-PrEP controls. PrEP protected 4 macaques from infection. Two of the four showed evidence of chemo-vaccination, because they developed anti-SHIV CD4(+) and CD8(+) T cells; SHIV-specific antibodies were not detected. Control macaques showed no anti-SHIV immune responses before infection. Chemo-vaccination-induced T cell responses were robust (up to 3,940 SFU/10(6) PBMCs), predominantly central memory cells, short-lived (≤22 weeks), and appeared intermittently and with changing specificities. The two chemo-vaccinated macaques were virus-challenged again after 28 weeks of rest, after T cell responses had waned. One macaque was not protected from infection. The other macaque concurrently received additional PrEP. It remained uninfected and T cell responses were boosted during the additional virus exposures. In summary, we document and characterize PrEP-induced T cell chemo-vaccination. Although not protective after subsiding in one macaque, chemo-vaccination-induced T cells warrant more comprehensive analysis during peak responses for their ability to prevent or to control infections after additional exposures. Our findings highlight the importance of monitoring these responses in clinical PrEP trials and suggest that a combination of vaccines and PrEP potentially might enhance efficacy.