pH-triggered polymeric nanoparticles in gel for preventing vaginal transmission of HIV and unintended pregnancy

Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/ AIDS) and unplanned pregnancy affect female reproductive health globally. A single product providing a dual purpose of HIV prophylaxis and contraception may improve adherence to the therapy. Thus, we formulated a female-centric multipurpose prevention technology (MPT) comprising of nanoparticle loaded vaginal gel formulation acting as a contraceptive and microbicide. Eudragit® S100 nanoparticles of Atazanavir sulphate (ATZ; antiviral) and Fluoxetine hydrochloride (FLX; repurposed spermicide) were prepared for pH dependent drug release and loaded in carrageenan and HPMC K200M gel. The particle size of ATZ and FLX nanoparticles was 396.7 ± 20.64 nm and 226.5 ± 2.08 nm respectively. The in vitro release of the gel formulation in simulated seminal fluid (pH 7.6) showed 96.16% and 95.98% release of ATZ and FLX respectively at the end of 8 h. The in vitro anti-HIV and spermicidal activity of the formulation was above 80% for low drug concentrations. In vivo studies on murine model showed no signs of inflammation or vaginal epithelial injury. Curcumin based imaging confirmed the retention of the formulation in the reproductive tract of mice with minimal leakage. Nanoparticles in gel enabled non-invasive and localised delivery with minimal side effects and can be an effective prophylactic therapy.

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.

Transfusion-Acquired HIV: History, Evolution of Screening Tests, and Current Challenges of Unreported Antiretroviral Drug Use in Brazil

Prevention of HIV acquisition by blood transfusion from its emergence to the present day is reviewed, and current challenges are delineated. The experience of Fundação Pró-Sangue/Hemocentro de São Paulo, Brazil, is highlighted in the quest for improvements in blood safety and the evolution of increasingly sensitive and specific screening tests. Concerns and establishing stringent criteria in the screening of potential blood donors are emphasized, and the current criteria for identifying and deferring candidates at high risk of acquiring sexually transmitted diseases are summarized. Future challenges relate to the identification of donors with unreported use of antiretroviral drugs for prophylaxis against possible HIV exposure or for treatment of an HIV infection whose viral expression is undetectable by current analyses. There is a need to better understand the motivation of HIV-exposed donors and to educate them about the risk of transfusion-mediated HIV transmission despite having low or undetectable viral loads. In situations in which traditional HIV RNA or antibody detection assays remain negative, more sensitive analyses are needed to identify potential donors at risk for HIV transmission.

Maternal PrEP Use in HIV-Uninfected Pregnant Women in South Africa: Role of Stigma in PrEP Initiation, Retention and Adherence

Pregnant women in sub-Saharan Africa are at high risk of HIV acquisition and require effective methods to prevent HIV. In a cohort of pregnant women offered Pre-exposure prophylaxis (PrEP), we evaluate the relationship between internalized and anticipated stigma and PrEP initiation at first antenatal visit, 3-month continuation and adherence using multivariable logistic regression. High internalized and anticipated PrEP stigma are associated with lower PrEP care initiation at first antenatal visit (aOR internalized stigma = 0.06; 95% CI = 0.03–0.11 and aOR anticipated stigma = 0.55; 95% CI = 0.31–1.00) compared to women with low reported stigma, after controlling for covariates. Women whose partners have not been tested for HIV or whose serostatus remains unknown have 1.6-times odds of PrEP retention at 3-months compared to women whose partners have been tested (aOR = 1.60; 95% CI = 1.02–2.52) after adjusting for covariates. PrEP counseling and maternal PrEP interventions must consider individual- and relational-level interventions to overcome anticipated PrEP stigma and other barriers to PrEP initiation and adherence.

Influence of unreported HIV prophylaxis on the kinetics of post-blood donation HIV seroconversion

BACKGROUND

In 2020, of 110,000 blood donors screened for HIV exposure two individuals were identified who were viral RNA-positive but seronegative. One of the donors, borderline negative in a pooled screening test for HIV RNA, utilized antiretroviral drugs as post-exposure, pre-donation prophylaxis. The kinetics of subsequent HIV seropositivity in both donors are described.

STUDY DESIGN AND METHODS

Both donors were recalled and interviewed, and blood was obtained at intervals for HIV antibodies and RNA testing.

RESULTS

One donor used antiretroviral prophylaxis for 30 days due to a relationship with an HIV-positive partner. In follow-up samples, seroconversion was noted at 70 days, and viral RNA was detected at 105 days, after blood donation. In contrast, the other donor seroconverted in <25 days and the appearance and titer of HIV RNA was in accordance with the typical pre-seroconversion window.

CONCLUSION

The use of anti-viral prophylaxis by blood donors in the acute phase of HIV infection delays seroconversion. A 6-month deferral in blood donation after HIV prophylaxis, as currently recommended in Brazil, would have been sufficient in this case to mitigate the risk of transfusion-transmitted HIV. Ultimately, improvement in donor compliance with selection procedures for blood donation is needed to optimize blood safety.

Emergence of Nanotechnology to Fight HIV Sexual Transmission: The Trip of G2-S16 Polyanionic Carbosilane Dendrimer to Possible Pre-Clinical Trials

Development of new, safe, and effective microbicides to prevent human immunodeficiency virus HIV sexual transmission is needed. Unfortunately, most microbicides proved ineffective to prevent the risk of HIV-infection in clinical trials. We are working with G2-S16 polyanionic carbosilane dendrimer (PCD) as a new possible vaginal topical microbicide, based on its short reaction times, wide availability, high reproducibility, and quantitative yields of reaction. G2-S16 PCD exerts anti-HIV activity at an early stage of viral replication, by blocking gp120/CD4/CCR5 interaction, and providing a barrier against infection for long periods of time. G2-S16 PCD was stable at different pH values, as well as in the presence of seminal fluids. It maintained the anti-HIV activity against R5/X4 HIV over time, did not generate any type of drug resistance, and retained the anti-HIV effect when exposed to semen-enhanced viral infection. Importantly, G2-S16 PCD did not modify vaginal microbiota neither in vitro or in vivo. Histopathological examination did not show vaginal irritation, inflammation, lesions, or damage in the vaginal mucosa, after administration of G2-S16 PCD at different concentrations and times in female mice and rabbit animal models. Based on these promising data, G2-S16 PCD could become a good, safe, and readily available candidate to use as a topical vaginal microbicide against HIV.

An audit of mother to child HIV transmission rates and neonatal outcomes at a tertiary hospital in South Africa

Objective

The aim of this study was to explore the prevalence of congenital HIV infection of neonates at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) between 2015 and 2017, as well as compare the HIV PCR positive and HIV PCR negative neonates.

Results

A total number of 1443 HIV exposed neonates was examined for the study period out of a total of 5029 admissions (HIV exposure 28.6%) The study found that the rate of HIV transmission at birth was 2.52%. The majority of infants had low birth weight and were also born prematurely. These results show that, despite the introduction of the extended mother to child transmission programme, HIV transmission is high.

Global implementation of PrEP for HIV prevention: setting expectations for impact

INTRODUCTION

Questions remain whether HIV pre-exposure prophylaxis (PrEP) can be translated into a successful public health intervention, leading to a decrease in population-level HIV incidence. We use examples from HIV treatment and contraceptives to discuss expectations for PrEP uptake, adherence, and persistence and their combined impact on the epidemic.

DISCUSSION

Targets for PrEP uptake must be based on the local HIV epidemic and will depend on appropriate estimates of the key populations at risk for HIV. However, there is evidence that targets, once established, can successfully be met and that uptake may increase with awareness. Messaging around adherence should include that daily adherence is the goal (except for those MSM for whom event-driven dosing is a good fit), but perfect adherence should not be a barrier. Ideally, clients persist on PrEP for as long as they are at risk for HIV. While PrEP will be most effective when coverage is focused on high-risk populations, normalizing rather than stigmatizing PrEP will be highly beneficial.

CONCLUSIONS

While many challenges to PrEP implementation exist, we focused on the three key steps of uptake, adherence and persistence as measurable processes that can lead to improved coverage and decreased HIV incidence.

Suspected unexpected and other adverse reactions to antiretroviral drugs used as post-exposure prophylaxis of HIV infection - five-year experience from clinical practice

INTRODUCTION

With increased use of antiretroviral drugs (ARVs) in HIV uninfected persons, proper reporting on suspected unexpected serious adverse reactions (SUSARs) and continued insight into adverse drug reactions (ADRs) are needed for adequate information on safety of ARVs in such populations.

MATERIAL AND METHODS

Medical documentation of persons receiving ARVs after non-occupational HIV exposure (non-occupational post-exposure prophylaxis - nPEP) during 5 successive years (2009-2013) was evaluated by two HIV physicians. Adverse drug reactions s and SUSARs were defined according to international standards. In statistical analyses Cox proportional hazard models were used to identify independent predictors of developing a first ADR.

RESULTS

In total 375 persons received nPEP with the following indications: needle stick (43%), unprotected sexual intercourse (17%), rape (10%) and first aid (10%). In 84 (22%) cases the source patient was HIV positive or an active injecting drug user. In total 170 ADRs were reported. One hundred thirty-nine persons had only 1 ADR. The most frequent first ADRs were gastrointestinal disorders (22%), followed by general symptoms (9%), hypersensitivity reactions (1.6%) and CNS symptoms (1.3%). The remaining events represented less than 1% of all patients. Eight (2.1%) patients developed a SUSAR. In multivariate analyses only age at first visit to the clinic was an independent predictor of developing an ADR (HR = 1.17, 95% CI: 1.03-1.34; p = 0.02).

CONCLUSIONS

In our observations ADRs in reaction to nPEP were frequent yet usually mild events, mostly occurring in the first 2 weeks and rarely causing discontinuation. The only significant factor increasing the risk of ADR was age. SUSARs were rare, transient and clinically insignificant.

Interest in multipurpose prevention technologies to prevent HIV/STIs and unintended pregnancy among young women in the United States

OBJECTIVE

High rates of sexually transmitted infections (STIs) and unintended pregnancy suggest a role for multipurpose prevention technologies (MPTs) designed to combine contraception and infection prophylaxis into one unified method. This study aims to determine factors associated with interest in MPTs among US women.

STUDY DESIGN

We administered a national cross-sectional survey via MTurk. Eligibility criteria included female gender, age 18-29 years, residence in the USA, and sexual activity with a male partner in the past three months. In total, 835 surveys were suitable for analysis. Bivariable and multivariable logistic regressions were performed to determine factors associated with interest in MPTs.

RESULTS

Eighty-three percent of women were interested in MPTs. Factors associated with interest included oral sex in the past three months (aOR 1.87, 95% CI 1.07, 3.53), recent use of oral contraceptive pills (OCPs; aOR 1.78, 95% CI 1.08, 2.93), HIV test within one year (aOR 2.10, 95% CI 1.29, 3.40), and increased STI worry score (aOR 1.98, 95% CI 1.36, 2.86). No use of contraception in the past three months was associated with decreased interest in MPTs (aOR 0.31, 95% CI 0.17, 0.58). HIV risk factors including race were not associated with MPT interest.

CONCLUSION

Our data show that young, sexually active, US women are interested in MPTs. Women who used contraception, specifically OCPs, or evidenced concern for infection were most likely to be interested in such a product. Women reporting unsafe sexual habits were less likely to be interested, highlighting the importance of HIV/STI prevention education.

IMPLICATIONS

Women in the USA are interested in multipurpose prevention technologies, particularly those women who currently use contraception or are concerned about their risk of infection. Our results emphasize the importance of moving forward with MPT development as well as continued HIV/STI prevention education.

Degradable bioadhesive nanoparticles for prolonged intravaginal delivery and retention of elvitegravir

New methods for long-lasting protection against sexually transmitted disease, such as the human immunodeficiency virus (HIV), are needed to help reduce the severity of STD epidemics, especially in developing countries. Intravaginal delivery of therapeutics has emerged as a promising strategy to provide women with local protection, but residence times of such agents are greatly reduced by the protective mucus layer, fluctuating hormone cycle, and complex anatomical structure of the reproductive tract. Polymeric nanoparticles (NPs) capable of encapsulating the desired cargo, penetrating through the mucosal surfaces, and delivering agents to the site of action have been explored. However, prolonged retention of polymer carriers and their enclosed materials may also be needed to ease adherence and confer longer-lasting protection against STDs. Here, we examined the fate of two poly (lactic acid)-hyperbranched polyglycerols (PLA-HPG) NP formulations - 1) nonadhesive PLA-HPG NPs (NNPs) and 2) surface-modified bioadhesive NPs (BNPs) - loaded with the antiretroviral elvitegravir (EVG) after intravaginal administration. BNP distribution was widespread throughout the reproductive tract, and retention was nearly 5 times higher than NNPs after 24 h. Moreover, BNPs were found to be highly associated with submucosal leukocytes and epithelial cell populations for up to 48 h after topical application, and EVG was retained significantly better in the vaginal lumen when delivered with BNPs as opposed to NNPs over a 24 h period. Our results suggest that bioadhesive PLA-HPG NPs can greatly improve and prolong intravaginal delivery of agents, which may hold potential in providing sustained protection over longer durations.

Prevalence of HIV infection among survivors of sexual assault at presentation in hospital

Victims of sexual assaults are routinely tested for HIV in order to discover if they require prophylaxis. This study aimed to determine the prevalence of HIV infection among survivors of sexual assault attending a large peri-urban health facility in KwaZulu-Natal, a province of South Africa. Data from the medical records of the available 534 sexual assault cases that attended the facility between 2005 and 2009 were extracted and reviewed: 19.7% tested HIV positive and HIV prevalence among the survivors over the 5 years increased from 15% in 2005 to 19% in 2009. Screening sexual assault survivors for HIV provides a good opportunity to identify those who will benefit from HIV prophylaxis and HIV-infected persons who need HIV care and treatment.