Multipurpose prevention technologies: the future of HIV and STI protection

Long-acting injectable multipurpose prevention technology for prevention of HIV and unplanned pregnancy

Only condoms are proven to protect against both HIV and unplanned pregnancy, however, poor user acceptability and lack of partner cooperation impede effectiveness. We developed an injectable ultra-long-acting, biodegradable, and removable in-situ forming implant (ISFI) as multipurpose prevention technology (MPT). MPT ISFIs co-formulated an antiretroviral (dolutegravir (DTG)) or cabotegravir (CAB)), and a hormonal contraceptive (etonogestrel (ENG) or medroxyprogesterone acetate (MPA)). All formulations were well-tolerated in mice with no signs of chronic local or systemic inflammation. Plasma CAB and DTG concentrations were above 4× PA-IC90 for 90 days with zero-order and diffusion-controlled absorption, respectively, and no differences when co-formulated with either hormone. Plasma ENG and MPA concentrations were quantifiable for 90 days. Complete removal of CAB/MPA ISFIs resulted in MPA concentrations falling below the limit of quantification after 24 h post-removal, but incomplete CAB elimination from plasma. Collectively, we demonstrated the ability to co-formulate antiretrovirals with contraceptives in an ISFI that is well-tolerated with sustained plasma concentrations up to 90 days.

Women Want Choices: Opinions from the Share.Learn.Shape Global Internet Survey About Multipurpose Prevention Technology (MPT) Products in Development

Women need multipurpose prevention technologies (MPTs) to simultaneously prevent sexually transmitted infections (STIs), including HIV, with or without contraception. User feedback early in product development is critical for maximizing uptake and continuation. Our global online survey (April 2017-December 2018) explored women's opinions about MPT formulations in development (e.g., fast-dissolving vaginal inserts, vaginal films, intravaginal rings, injectables, implants), preferences for long-acting or "on-demand" methods, and interest in a contraceptive MPT versus products for HIV/STI prevention alone. Of the 630 women in our final analysis (mean 30 years old; range 18-49), 68% were monogamous, 79% completed secondary education, 58% had ≥ 1 child, 56% were from sub-Saharan Africa and 82% preferred a cMPT versus HIV/STI prevention alone. There were no clear preferences for any specific product or product type (long-acting, on-demand, daily). No single product will appeal everyone, however, adding contraception is likely to increase uptake of HIV/STI prevention methods for most women.

Co-delivery of an HIV prophylactic and contraceptive using PGSU as a long-acting multipurpose prevention technology

OBJECTIVES

Poly(glycerol sebacate) urethane (PGSU) elastomers formulated with 4'-ethynyl-2-fluoro-2'-deoxyadenosine (EFdA), levonorgestrel (LNG), or a combination thereof can function as multipurpose prevention technology implants for prophylaxis against HIV and unintended pregnancies. For these public health challenges, long-acting drug delivery technologies may improve patient experience and adherence. Traditional polymers encounter challenges delivering multiple drugs with dissimilar physiochemical properties. PGSU offers an alternative option that successfully delivers hydrophilic EFdA alongside hydrophobic LNG.

METHODS

This article presents the formulation, design, and characterization of PGSU implants, highlighting the impact of API loading, dimensions, and individual- versus combination-loading on release rates.

RESULTS

Co-delivery of hydrophilic EFdA alongside hydrophobic LNG acted as a porogen to accelerate LNG release. Increasing the surface area of LNG-only implants increased LNG release. All EFdA-LNG, EFdA-only, and LNG-only formulated implants demonstrated low burst release and linear release kinetics over 245 or 122 days studied to date.

CONCLUSION

PGSU co-delivers two APIs for HIV prevention and contraception at therapeutically relevant concentrations in vitro from a single bioresorbable, elastomeric implant. A new long-acting polymer technology, PGSU demonstrates linear-release kinetics, dual delivery of APIs with disparate physiochemical properties, and biocompatibility through long-term subcutaneous implantation. PGSU can potentially meet the demands of complex MPT or fixed-dose combination products, where better solutions can serve and empower patients.

TRICHOMONAS VAGINALIS INFECTION AMONG ASYMPTOMATIC UNDERGRADUATE STUDENTS IN A PRIVATE UNIVERSITY IN OGUN STATE, NIGERIA

Background

Trichomonas vaginalis is one of the common non- viral sexually transmitted infections that infect both men and women worldwide. It is largely asymptomatic and its association with the risk of HIV transmission has made it a compelling public health concern. Therefore, this study aims to determine the prevalence and the risk factors associated with T. vaginalis among asymptomatic undergraduate students at Babcock University, Ilisan-Remo, Ogun state, Nigeria.

Materials and Methods

This is a descriptive cross-sectional study involving 246 asymptomatic students of Babcock University between February 2019 to April 2020. Information on socio-demographic and associated risk factors was obtained by structured-questionnaire in an interview-based manner. First-void urine was collected from each participant for the detection of T. vaginalis using the traditional wet prep method and TV in-pouch. The data were analyzed by SPSS Version 23.

Results

The overall prevalence of T. vaginalis among the participants was 12.2% (30/246). The use of wet-preparation showed 8.5% (21/246) while the use of TV inpouch yielded 12. 2% (30/246) prevalence of positive results. The results of the wet prep in comparison to the in-pouch technique was statistically significant among the study population. (P < 0.001). Sexual intercourse, use of hormonal contraceptives and practice of internet-based sex seeking behaviour were factors that had increase likelihood of T. vaginalis infection on multivariate analysis.

Conclusion

The occurrence of T. vaginalis and, its associated risk factors among the asymptomatic population in this study is very high. We advocate for the screening of young people.

Acceptability of PC-1005 Gel Administered Rectally to HIV-1 Seronegative Adults at Three Different Volume Levels (MTN-037)

Multipurpose prevention technologies (MPT) have been increasingly researched for their dual-purpose preventative properties against HIV and other STIs. The acceptability of PC-1005, a topical MPT candidate, was explored among men and women participating in the MTN-037 Phase I trial at two U.S. sites (Pittsburgh, PA, and Birmingham, AL). We triangulated quantitative and qualitative assessments of the acceptability of three volumes (4 mL, 16 mL, 32 mL) of PC-1005 administered rectally (N = 12; 6 males, 6 females). Participants rated overall gel acceptability on a scale of 1-10, with a median of 7.17 (SD = 2.04) and had positive feelings about all three dose volumes, citing them to be very comfortable or comfortable (dose 1 = 91.7%; dose 2 = 91.7%; dose 3 = 83.3%). High acceptability of and comfort with all three dose volumes shows promise for PC-1005 as an MPT to prevent HIV and STIs, warranting future clinical development.

HIV Pre-exposure Prophylaxis Implant Stated Preferences and Priorities: Results of a Discrete Choice Experiment Among Women and Adolescent Girls in Gauteng Province, South Africa

For adolescent girls (AG) and young women (YW), adherence barriers may limit the effectiveness of daily oral HIV pre-exposure prophylaxis (PrEP). Due to its low-burden and long-lasting product attributes, PrEP implants could remove some of the critical adherence barriers of oral PrEP products for individuals at risk of HIV. To explore stated preferences for a long-acting PrEP implant, we conducted a quantitative survey and discrete choice experiment with AG (ages 15-17), YW (18-34), and female sex workers (FSW; ≥ 18) in Gauteng Province, South Africa. We completed 600 quantitative surveys across the three subgroups of women. Respondents stated preference for an implant that provided longer HIV protection (24 months versus 6 months) and required a single insertion. They stated that they preferred a biodegradable implant that could be removed within 1 month of insertion. Respondents had no preference for a particular insertion location. Overall, 78% of respondents said they would be likely (33%) or very likely (45%) to use a PrEP implant were one available, with the majority (82%) stating preference for a product that would provide dual protection against HIV and unintended pregnancies. To reduce their risk of HIV, AG, YW, and FSW in our survey reported a strong willingness to use long-acting, highly-effective, dissolvable PrEP implants.

Results of a phase 1, randomized, placebo-controlled first-in-human trial of griffithsin formulated in a carrageenan vaginal gel

HIV pre-exposure prophylaxis (PrEP) is dominated by clinical therapeutic antiretroviral (ARV) drugs. Griffithsin (GRFT) is a non-ARV lectin with potent anti-HIV activity. GRFT’s preclinical safety, lack of systemic absorption after vaginal administration in animal studies, and lack of cross-resistance with existing ARV drugs prompted its development for topical HIV PrEP. We investigated safety, pharmacokinetics (PK), pharmacodynamics (PD), and immunogenicity of PC-6500 (0.1% GRFT in a carrageenan (CG) gel) in healthy women after vaginal administration. This randomized, placebo-controlled, parallel group, double-blind first-in-human phase 1 study enrolled healthy, HIV-negative, non-pregnant women aged 24–45 years. In the open label period, all participants (n = 7) received single dose of PC-6500. In the randomized period, participants (n = 13) were instructed to self-administer 14 doses of PC-6500 or its matching CG placebo (PC-535) once daily for 14 days. The primary outcomes were safety and PK after single dose, and then after 14 days of dosing. Exploratory outcomes were GRFT concentrations in cervicovaginal fluids, PD, inflammatory mediators and gene expression in ectocervical biopsies. This trial is registered with ClinicalTrials.gov, number NCT02875119. No significant adverse events were recorded in clinical or laboratory results or histopathological evaluations in cervicovaginal mucosa, and no anti-drug (GRFT) antibodies were detected in serum. No cervicovaginal proinflammatory responses and no changes in the ectocervical transcriptome were evident. Decreased levels of proinflammatory chemokines (CXCL8, CCL5 and CCL20) were observed. GRFT was not detected in plasma. GRFT and GRFT/CG in cervicovaginal lavage samples inhibited HIV and HPV, respectively, in vitro in a dose-dependent fashion. These data suggest GRFT formulated in a CG gel is a safe and promising on-demand multipurpose prevention technology product that warrants further investigation.

Drug-releasing vaginal rings for HIV/STI and pregnancy prevention: A review of recent advances and clinical applications

INTRODUCTION

Adolescent girls and young women (AGYW), as well as pre- and post-menopausal women globally would benefit from expanded choice to address their sexual and reproductive health (SRH) needs related to Human Immunodeficiency Virus (HIV), sexually transmitted infections (STIs) and pregnancy prevention. Lack of adequate preventative vaccines for HIV/STIs reinforces public health prioritization for options women may use independently to mitigate risk for infectious disease and unplanned pregnancy. Drug releasing intravaginal rings (IVR) represent one such technology that has garnered attention based on the modality's success recently as a pre-exposure prophylaxis (PrEP) delivery option and its impact on reduction in HIV risk.

AREAS COVERED

: This article provides a synopsis of three IVR technologies in active clinical development for prevention of HIV, STI, and unintended pregnancy demonstrating advancements in terms of compatibility with a wide range of drug types with a focus on dapivirine-based silicone rings (International Partnership for Microbicides (IPM), tenofovir-based polyurethane rings (CONRAD), and pod-based rings (Oak Crest Institute of Science).

EXPERT OPINION

The goals of IVR research are to reduce burdens of HIV/STIs and unplanned pregnancies. Through the evolution of IVR technologies, the potential exists to trigger integration of healthcare services through formulation of products with multiple indications.

Long-acting biodegradable implant for sustained delivery of antiretrovirals (ARVs) and hormones

Women worldwide confront two major reproductive health challenges: the need for contraception and protection from sexually transmitted infections, including Human Immunodeficiency Virus (HIV). Multipurpose Prevention Technologies (MPTs) that simultaneously prevent unintended pregnancy and HIV could address these challenges with a single product. Here, we developed a long-acting (LA) subcutaneously administered and biodegradable implant system that provides sustained delivery of contraceptive and antiretroviral (ARV) with zero-order release kinetics. The MPT system involves two implants comprising an extruded tube of a biodegradable polymer, poly(ε-caprolactone) (PCL). Each implant is filled with a formulation of progestin [levonorgestrel (LNG) or etonogestrel (ENG)], or a formulation of a potent ARV [tenofovir alafenamide (TAF), or 4'-Ethynyl-2-fluoro-2'-deoxyadenosine (EFdA)]. We demonstrated sustained in-vitro release of LNG, ENG, and EFdA from the implant system for 13-17 months, while maintaining high stability of the drugs (>99%) within the implant reservoirs. We further elucidated the controlled release mechanism of the implant and leveraged several tunable parameters (e.g., type and quantity of the excipient, PCL properties, and implant wall thickness) to tailor the release kinetics and enhance the mechanical integrity of the MPT implant. The optimized MPT showed sustained in-vitro release of ENG and EFdA over 1 year while maintaining a high level of formulation stability and structural integrity. The MPT implant system was further evaluated in a preclinical study using a rodent model and demonstrated sustained release of EFdA (6 months) and ENG (12 months) with high stability of the drug formulation (>95%). This manuscript supports the continued advancement of LA delivery systems for MPTs.

Recent advances in electrospun nanofiber vaginal formulations for women's sexual and reproductive health

Electrospinning is an innovative technique that allows production of nanofibers and microfibers by applying a high voltage to polymer solutions of melts. The properties of these fibers - which include high surface area, high drug loading capacity, and ability to be manufactured from mucoadhesive polymers - may be particularly useful in a myriad of drug delivery and tissue engineering applications. The last decade has witnessed a surge of interest in the application of electrospinning technology for the fabrication of vaginal drug delivery systems for the treatment and prevention of diseases associated with women's sexual and reproductive health, including sexually transmitted infections (e.g. infection with human immunodeficiency virus and herpes simplex virus) vaginitis, preterm birth, contraception, multipurpose prevention technology strategies, cervicovaginal cancer, and general maintenance of vaginal health. Due to their excellent mechanical properties, electrospun scaffolds are also being investigated as next-generation materials in the surgical treatment of pelvic organ prolapse. In this article, we review the latest advances in the field.

Development of multipurpose technologies products for pregnancy and STI prevention: update on polyphenylene carboxymethylene MPT gel development†

Current modern contraceptives rely heavily on the use of hormones. These birth control drug products, including pills, patches, injections, and IUDS, have been extremely beneficial to millions of women and their families over the past 50 years. But a surprisingly high number of women abandon such modern methods, many because they cannot tolerate the side effects and others because they have medical issues for which hormonal methods are contraindicated. In addition, modern hormonal methods are simply not available to many women. The extent of this problem is steadily becoming more apparent. We present the case for developing simple nonhormonal vaginal products that women can use when needed, ideal products that are multipurpose and offer both contraception and sexually transmitted disease protection. Gel-based vaginal products are particularly well suited for this purpose. Gels are easy to use, highly acceptable to many women, and can be safely formulated to enhance natural vaginal defenses against infection. However, the development of a new chemical entity for this application faces significant technical and regulatory hurdles. These challenges and our solutions are described for polyphenylene carboxymethylene (PPCM), a novel topical drug in a vaginal gel nearing human clinical trials. We have advanced PPCM from benchtop to IND-enabling studies and provide a brief description of the complex development process. We also describe a simple lab assay which can be used as a biomarker for contraceptive activity to enable pharmacodynamic studies in vaginal contraceptive development, both preclinically and in early human clinical trials.

Recent Advances and New Challenges in Cisgender Women's Gynecologic and Obstetric Health in the Context of HIV

Although rates of human immunodeficiency virus (HIV) have declined globally over the past 10 years, United Nations Programme on HIV/AIDS estimates 1.7 million new infections occurred in 2019, with cisgender women (cis women) and girls accounting for 48%. Acquired immune deficiency syndrome-related illnesses are the leading global cause of mortality in cis women aged 15 to 49, and in many sub-Saharan Africa countries, young women face substantially higher HIV risk than their male counterparts. Drivers of this increased risk include sexual and reproductive health characteristics unique to cis women. This review discusses the role of sexually transmitted infections, contraception and pregnancy in HIV risk, and biomedical HIV prevention technologies available and in development.

Multipurpose Prevention Technologies: Oral, Parenteral, and Vaginal Dosage Forms for Prevention of HIV/STIs and Unplanned Pregnancy

There is a high global prevalence of HIV, sexually transmitted infections (STIs), and unplanned pregnancies. Current preventative daily oral dosing regimens can be ineffective due to low patient adherence. Sustained release delivery systems in conjunction with multipurpose prevention technologies (MPTs) can reduce high rates of HIV/STIs and unplanned pregnancies in an all-in-one efficacious, acceptable, and easily accessible technology to allow for prolonged release of antivirals and contraceptives. The concept and development of MPTs have greatly progressed over the past decade and demonstrate efficacious technologies that are user-accepted with potentially high adherence. This review gives a comprehensive overview of the latest oral, parenteral, and vaginally delivered MPTs in development as well as drug delivery formulations with the potential to advance as an MPT, and implementation studies regarding MPT user acceptability and adherence. Furthermore, there is a focus on MPT intravaginal rings emphasizing injection molding and hot-melt extrusion manufacturing limitations and emerging fabrication advancements. Lastly, formulation development considerations and limitations are discussed, such as nonhormonal contraceptive considerations, challenges with achieving a stable coformulation of multiple drugs, achieving sustained and controlled drug release, limiting drug-drug interactions, and advancing past preclinical development stages. Despite the challenges in the MPT landscape, these technologies demonstrate the potential to bridge gaps in preventative sexual and reproductive health care.

The Promise of the Dual Prevention Pill: A Framework for Development and Introduction

Women of reproductive age need multipurpose prevention technology (MPT) products to address two overlapping health risks: unintended pregnancy and HIV. Currently, condoms are the only available MPT, however male condoms are not within the control of a woman, and the use of female condoms has been limited by low acceptability and cost. Oral pre-exposure prophylaxis (PrEP) is highly effective for HIV prevention, yet uptake and adherence among women have been low to date. Women globally need more options for HIV and pregnancy prevention. Several MPTs for simultaneous HIV and pregnancy prevention are in various stages of development and clinical testing, although most are many years away from market launch. A dual prevention pill (DPP), a daily oral pill combining oral contraceptives and PrEP, both of which are licensed, approved products in many low- and middle-income countries (LMIC), is likely to be the fastest route to getting an MPT product into the hands of women. The DPP is one option that could enhance method choice, particularly for women who are already using oral contraceptives. By leveraging the oral contraceptive market and reaching women currently using condoms or with an unmet need for contraception, the DPP has the potential to increase the uptake of PrEP. The successful rollout of the DPP will require careful consideration of user-, provider-, and product-centered factors during product development and introduction. Early attention to these interrelated factors can help ensure that the DPP has the ideal characteristics for maximum product acceptability, that effective and quality services are designed and implemented, and that users can make informed choices, demand the product, and use it effectively. The proposed framework outlines key considerations for the effective development and introduction of the DPP, which could also facilitate integration models for future MPTs.

In vitro inhibitory activity against HPV of the monoterpenoid zinc tetra-ascorbo-camphorate

Zinc tetra-ascorbo-camphorate (or drug "C14") is a synthetic monoterpenoid derivative that has potent anti-HIV-1 activity in vitro. In this study, we evaluated the in vitro antiviral properties of C14 against human papillomavirus (HPV). Inhibition assay of HPV-16-pseudovirus (PsVs) adsorption on COS-7 cells by C14 was used. C14 inhibited HPV-16-PsVs adsorption with IC₅₀ ranging between 2.9 and 8.3 μM and therapeutic indexes between >410 to >3,300. Pretreatment of COS-7 cells with C14 before addition of HPV-16-PsV was associated with more potent anti-HPV activity than simultaneous deposition on COS-7 of HPV-16-PsV and C14, suggesting that C14 is more effective in preventing HPV attachment to target cells than post-HPV adsorption viral events. Overall, these in vitro studies suggest that the monoterpenoid zinc tetra-ascorbo-camphorate molecule may be suitable for further clinical evaluations as potential microbicide or therapeutic drug.

The Potential Impact of a Gel-Based Point-of-Sex Intervention in Reducing Gonorrhea Incidence Among Gay and Bisexual Men: A Modeling Study

BACKGROUND

Increases in sexually transmitted infections among gay and bisexual men (GBM) over the past decade have coincided with declines in condom use and rapid uptake of HIV preexposure prophylaxis (PrEP). We explored the impact of an antimicrobial gel-based point-of-sex intervention (gel-PSI) with a lower efficacy for reducing gonorrhea transmission risk than condoms on population-level gonorrhea incidence among GBM in Victoria, Australia.

METHODS

A deterministic compartmental model of HIV and gonorrhea transmission was used to project annual gonorrhea incidence from 2020 to 2025. Individuals were classified as HIV-negative (PrEP or non-PrEP users) or HIV-positive, and further stratified by gonorrhoea risk (high/low). All possible scenarios where between 0% and 100% of GBM using condoms transitioned to gel-PSI (considered a downgrade in protection) and 0% and 100% of GBM not using condoms transitioned to gel-PSI (considered an upgrade in protection), with gel-PSI efficacy ranging from 20% to 50%, were run.

RESULTS

The baseline scenario of no gel-PSI uptake (status quo) projected 94,367 gonorrhea infections between 2020 and 2025, with an exponentially increasing trend in annual infections. For a gel-PSI efficacy of 30%, a net reduction in cumulative gonorrhea incidence was projected, relative to the status quo, for any ratio of proportion of condom users "downgrading" to proportion of noncondom users "upgrading" to gel-PSI use of less than 2.6. Under the supposition of equal proportions of condom users and noncondom users switching to gel-PSI, a relative reduction was projected for any gel-PSI efficacy greater than 16%.

CONCLUSIONS

Our model suggests that the introduction of a gel-PSI could have benefits for controlling gonorrhea transmission among GBM, even in scenarios where the gel-PSI is considerably less efficacious than condoms and when gel-PSI uptake leads to consequent reductions in consistent condom use.

Reproductive Life Goals: A Systematic Review of Pregnancy Planning Intentions, Needs, and Interventions Among Women Involved in U.S. Criminal Justice Systems

Background: Women involved in criminal justice systems (WICJ) are affected by multilevel biological and sociocultural factors that result in adverse health outcomes and health disparities. Criminal justice systems (CJS) must be appropriately resourced to address these issues. Materials and Methods: We developed a systematic review to understand the intentions and needs for pregnancy prevention and planning among WICJ to inform future reproductive health services. We conducted a systematic literature review of epidemiologic and interventional studies that addressed the pregnancy prevention and planning needs of U.S. WICJ (2000-2019). An initial screen identified 7061 articles and 3 independent reviewers determined that 28 articles (16 descriptive studies in adults, 7 descriptive studies in adolescents, and 5 interventional studies) met inclusion criteria. Results: The literature review identified high rates of contraception underutilization and negative attitudes toward pregnancy among WICJ in a wide variety of settings. WICJ described minimal access to reproductive health services, including evidence-based contraception, and experienced high rates of unplanned and undesired pregnancies. Results were interpreted in the context of the reproductive justice (RJ) framework. Conclusions: The CJS, although not designed to provide health care, should dedicate resources to address the multilevel barriers to care experienced by women. WICJ require targeted, gender-responsive, trauma-informed pregnancy prevention and planning interventions that acknowledge the history of reproductive coercion in this population and address key aspects of RJ, including the right to and to not have a child.

HIV prevention is not all about HIV - using a discrete choice experiment among women to model how the uptake and effectiveness of HIV prevention products may also rely on pregnancy and STI protection

INTRODUCTION

In sub-Saharan Africa, considerable HIV-burden exists among women. Anti-retroviral (ARV) based prevention products could decrease this burden, and their uptake could be increased if they also protect against pregnancy and sexually transmitted infections (STI).

METHODS

A discrete choice experiment (DCE) was undertaken in South Africa (2015) through a household survey of adult females (n = 158) and adolescent girls (n = 204) who self-reported HIV-negative status. The DCE was used to project the uptake (percentage using product) of oral pre-exposure prophylaxis (PrEP), vaginal rings, and injectable long-lasting ARV agents among these women, and how uptake could depend on whether these products protect against pregnancy or STI acquisition. Uptake estimates were used to model how each product could decrease a women's HIV acquisition risk.

RESULTS

In adolescent women, there will be limited uptake (< 6% for any product) and impact (< 4% decrease in HIV acquisition risk) of new products unless they provide pregnancy protection, which could quadruple use and impact. Adult women have weaker preference for pregnancy protection, with moderate use (< 17% for each) and impact (< 14 percentage point decrease) if they only provide HIV protection. All women had highest preference for injectable ARVs, with oral PrEP having high preference if injectable ARVs are not available. Adult women will use the ring, but adolescent women will not. Importantly, even with three additional prevention products, all providing pregnancy and STI protection, > 14% of women will remain unprotected and > 31% of the baseline acquisition risk will remain.

CONCLUSIONS

Incorporating multiple prevention components into new ARV-based prevention products may increase their uptake and impact among women.

Receptive anal sex contributes substantially to heterosexually acquired HIV infections among at-risk women in twenty US cities: Results from a modelling analysis

PROBLEM

Receptive anal intercourse (RAI) is more efficient than receptive vaginal intercourse (RVI) at transmitting HIV, but its contribution to heterosexually acquired HIV infections among at-risk women in the USA is unclear.

METHOD OF STUDY

We analysed sexual behaviour data from surveys of 9152 low-income heterosexual women living in 20 cities with high rates of HIV conducted in 2010 and 2013 as part of US National HIV Behavioral Surveillance. We estimated RAI prevalence (past-year RAI) and RAI fraction (fraction of all sex acts (RVI and RAI) at the last sexual episode that were RAI among those reporting past-year RAI) overall and by key demographic characteristics. These results and HIV incidence were used to calibrate a risk equation model to estimate the population attributable fraction of new HIV infections due to RAI (PAF_RAI ) accounting for uncertainty in parameter assumptions.

RESULTS

Receptive anal intercourse prevalence (overall: 32%, city range: 19%-60%) and RAI fraction (overall: 27%, city range: 18%-34%) were high overall and across cities, and positively associated with exchange sex. RAI accounted for an estimated 41% (uncertainty range: 18%-55%) of new infections overall (city range: 21%-57%). Variability in PAF_RAI estimates was most influenced by uncertainty in the estimate of the per-act increased risk of RAI relative to RVI and the number of sex acts.

CONCLUSION

Receptive anal intercourse may contribute disproportionately to new heterosexually acquired HIV infections among at-risk low-income women in the USA, meaning that tools to prevent HIV transmission during RAI are warranted. The number of RVI and RAI acts should also be collected to monitor heterosexually acquired HIV infections.

Vaginal multipurpose prevention technologies: promising approaches for enhancing women's sexual and reproductive health

Introduction: Multipurpose prevention technologies (MPTs) have the potential to avert multiple concomitant sexual and reproductive health issues in women such as sexually transmitted infections and unintended pregnancy. MPTs incorporate one or more active pharmaceutical ingredients in a single product, which adds more convenience for users and may promote increased adherence. Various vaginal dosage forms/delivery systems have been studied for designing MPTs. However, several challenges remain that are mainly related to requirements of individual drugs or intended multiple applications.Areas covered: This review focuses on the emerging need and development of vaginal MPTs. It illustrates numerous examples that are currently in the preclinical and clinical development pipeline, highlighting the concept behind vaginal MPTs. The article also highlights the challenges associated with formulation design and development, including regulatory issues that need to be addressed.Expert opinion: Vaginal MPTs present great potential to empower women with novel, efficient, and safe products for protection against sexually transmitted infections and unintended pregnancy. However, several technological issues and regulatory gaps still need to be addressed in order to meet real-world needs.

Acceptability and Predictors of Uptake of Anti-retroviral Pre-exposure Prophylaxis (PrEP) Among Fishing Communities in Uganda: A Cross-Sectional Discrete Choice Experiment Survey

We used a discrete choice experiment to assess the acceptability and potential uptake of HIV pre-exposure prophylaxis (PrEP) among 713 HIV-negative members of fishing communities in Uganda. Participants were asked to choose between oral pill, injection, implant, condoms, vaginal ring (women), and men circumcision. Product attributes were HIV prevention effectiveness, sexually transmitted infection (STI) prevention, contraception, waiting time, and secrecy of use. Data were analysed using mixed multinomial logit and latent class models. HIV prevention effectiveness was viewed as the most important attribute. Both genders preferred oral PrEP. Women least preferred the vaginal ring and men the implant. Condom use was predicted to decrease by one third among men, and not to change amongst women. Oral PrEP and other new prevention technologies are acceptable among fishing communities and may have substantial demand. Future work should explore utility of multiple product technologies that combine contraception with HIV and other STI prevention.

Acceptability and performance of a nonwoven device for vaginal drug delivery among women and their male partners in KwaZulu-Natal, South Africa

Background: Multipurpose prevention technologies are needed to provide protection against HIV and sexually transmitted infections. Gel-based vaginal microbicides inserted via an applicator are prone to leakage. A novel device for vaginal drug delivery was developed to contain gel-based formulations, aiming to improve gel retention and reduce leakage. The objectives of this study were to assess acceptability and performance of a nonwoven vaginal delivery device. Methods: A nonwoven vaginal delivery device was prepared, pre-saturated with a commercially available water-based lubricant, with a finger pocket for insertion and string for removal. Quantitative and qualitative methods were used to collect data from interviews with 40 women and 10 male partners recruited from a sexual and reproductive health clinic in Durban, KwaZulu-Natal, South Africa. Women wore one device in the clinic and one device overnight or with their partner during intercourse. The primary endpoint was acceptability including comfort, ease of insertion and removal, and opinions on device attributes. Results: Most women said the device was 'easy' to insert and remove. Six women reported leakage after insertion and 34 reported having sexual intercourse while wearing the device. One woman was lost-to-follow-up and five women only wore the device overnight because their partners did not agree to intercourse with the inserted device. The best-liked attribute was the device's lubrication (22 women, 7 men); the least-liked was the removal string (9 women, 8 men). Conclusions: Data are promising for further development of this nonwoven device for vaginal drug delivery. Plain English summary Multipurpose prevention technologies (MPTs) that protect against HIV and sexually transmitted infections (STIs) are urgently needed. A variety of vaginal gel-based products are actively being researched; however, these products can often have challenges with vaginal leakage and retention. This research investigates the acceptability and performance of a nonwoven device to deliver vaginal gel formulations. The gel used in this study was a currently available marketed personal lubricant. In South Africa, 40 women (and 10 male partners) were recruited and given the opportunity to comment on various device attributes after insertion, overnight wear and sexual intercourse with their male partners. Generally, participants found the device easy to use and acceptable, where many factors possibly contributed to the device's acceptability (i.e., similarity to tampons, saturation with lubricant, minimal leakage, ease of insertion, comfort during intercourse and the male partners' willingness to have vaginal intercourse with the device in place). Further studies of the vaginal delivery device for acceptability, safety and efficacy using a gel-based formulation with an active ingredient are warranted.

Towards a dapivirine and levonorgestrel multipurpose vaginal ring: Investigations into the reaction between levonorgestrel and addition-cure silicone elastomers

With a dapivirine-releasing vaginal ring having successfully completed late-stage clinical testing for HIV prevention and currently undergoing regulatory review, there is now growing interest in next-generation multipurpose prevention technologies that seek to combine antiretroviral and contraceptive drugs within a single product. Here, we focus on ongoing efforts to develop a silicone elastomer vaginal ring releasing both dapivirine and levonorgestrel. Specifically, we evaluate various strategies aimed at both better understanding and reducing the tendency of levonorgestrel to bind with the elastomer, including: (i) formulation and post-manufacturing strategies aimed at reducing the extent of levonorgestrel reaction with addition-cure silicone elastomers; (ii) evaluation of a simple silicone system to model the complex elastomer; (iii) use of model compounds representing the enone and ethinyl moieties of levonorgestrel to probe the mode of addition of levonorgestrel to addition-cure silicone elastomers; and (iv) solution and solid-state ¹³C NMR analysis to probe the structural features of the levonorgestrel-silicone system. The results demonstrate that both the enone and ethinyl groups within levonorgestrel undergo hydrosilylation reactions with the hydrosiloxane groups in the silicone elastomer leading to covalent binding. The results also highlight potential strategies for further optimising the dapivirine + levonorgestrel silicone vaginal ring formulation to ensure that the levonorgestrel is available for release.

The Tablets, Ring, Injections as Options (TRIO) study: what young African women chose and used for future HIV and pregnancy prevention

Introduction

Preventing HIV and unintended pregnancies are key global health priorities. To inform product rollout and to understand attributes of future multipurpose prevention technologies (MPT) associated with preference and use, we evaluated three placebo delivery forms: daily oral tablets, a monthly vaginal ring, and two monthly intramuscular injections in TRIO, a five‐month study among young Kenyan and South African women.

Methods

HIV‐negative, sexually active, non‐pregnant women aged 18 to 30 were enrolled and randomized to use each placebo delivery form for one month (stage 1). Then, participants chose one product to use for two additional months (stage 2). We assessed safety, product ranking, choice, and use. We examined demographic and behavioural correlates of choice and, reciprocally, unwillingness to use in the future with logistic regression models.

Results

277 women enrolled, 249 completed stage 1 and 246 completed stage 2. Median age was 23 years, 49% were Kenyan and 51% were South African. Three participants became pregnant during the study and one participant HIV‐seroconverted. There were 18 product‐related adverse events, six tablets‐related, 11 ring‐related, and one injection‐related. After trying each product, 85% preferred a TRIO product over condoms. Injections were chosen most (64%, 95% confidence interval (CI) 58%, 70%; p < 0.001), and by more South Africans than Kenyans (odds ratio (OR) 2.01, 95% CI: 1.17, 3.43; p = 0.01). There was no significant difference in choosing tablets versus ring (21%, 95% CI: 16%, 26% vs. 15%, 95% CI: 11%, 20%; p = 0.11). Tablet and ring adherence, based on direct observations and self‐reports, improved over time. However, participants’ self‐reported use of tablets did not match objective data from the electronic dose monitoring device. Participants were fully compliant with injections.

Conclusion

In this population at risk for HIV and pregnancy, all participants agreed to choose and use a placebo MPT delivery form. A majority of participants preferred TRIO products to male condoms, an existing MPT. Injections were most liked and best used, however, they are years away from reaching the clinics. In the meantime, expanding the availability of tablets and giving access to rings can begin to fulfill the promise of choice for HIV prevention technologies and inform the development of suitable delivery forms as MPT.

The cost-effectiveness of multi-purpose HIV and pregnancy prevention technologies in South Africa

Introduction

A number of antiretroviral HIV prevention products are efficacious in preventing HIV infection. However, the sexual and reproductive health needs of many women extend beyond HIV prevention, and research is ongoing to develop multi‐purpose prevention technologies (MPTs) that offer dual HIV and pregnancy protection. We do not yet know if these products will be an efficient use of constrained health resources. In this paper, we estimate the cost‐effectiveness of combinations of candidate multi‐purpose prevention technologies (MPTs), in South Africa among general population women and female sex workers (FSWs).

Methods

We combined a cost model with a static model of product impact based on incidence data in South Africa to estimate the cost‐effectiveness of five candidate co‐formulated or co‐provided MPTs: oral PrEP, intravaginal ring, injectable ARV, microbicide gel and SILCS diaphragm used in concert with gel. We accounted for the preferences of end‐users by predicting uptake using a discrete choice experiment (DCE). Product availability and protection were systematically varied in five potential rollout scenarios. The impact model estimated the number of infections averted through decreased incidence due to product use over one year. The comparator for each scenario was current levels of male condom use, while a health system perspective was used to estimate discounted lifetime treatment costs averted per HIV infection. Product benefit was estimated in disability‐adjusted life years (DALYs) averted. Benefits from contraception were incorporated through adjusting the uptake of these products based on the DCE and through estimating the costs averted from avoiding unwanted pregnancies. We explore the additional impact of STI protection through increased uptake in a sensitivity analysis.

Results

At central incidence rates, all single‐ and multi‐purpose scenarios modelled were cost‐effective among FSWs and women aged 16–24, at a governmental willingness‐to‐pay threshold of $1175/DALY averted (range: $214–$810/DALY averted among non‐dominant scenarios), however, none were cost‐effective among women aged 25–49 (minimum $1706/DALY averted). The cost‐effectiveness of products improved with additional protection from pregnancy. Estimates were sensitive to variation in incidence assumptions, but robust to other parameters.

Conclusions

To the best of our knowledge, this is the first study to estimate the cost‐effectiveness of a range of potential MPTs; suggesting that MPTs will be cost‐effective among higher incidence FSWs or young women, but not among lower incidence older women. More work is needed to make attractive MPTs available to potential users who could use them effectively.

Development and pharmacokinetics of a combination vaginal ring for sustained release of dapivirine and the protein microbicide 5P12-RANTES

The past fifteen years have witnessed a resurgence of interest in vaginal ring technologies for drug delivery applications, mostly driven by the impetus for development of vaginally-administered antiretroviral microbicides to help reduce the high acquisition rates for human immunodeficiency virus (HIV) among Sub-Saharan African women. Currently, the lead candidate microbicide is a 28-day silicone elastomer vaginal ring releasing dapivirine (Ring-004), an experimental non-nucleoside reverse transcriptase inhibitor. The ring was tested in two pivotal Phase III clinical studies in 2016 and is currently undergoing review by the European Medicines Agency. Recently, we described a new type of silicone elastomer vaginal ring offering sustained release of the protein molecule 5P12-RANTES, a potent experimental chemokine analogue that potently blocks the HIV CCR5 coreceptor. Building on our previous work, here we report the preclinical development of a new combination vaginal ring that offers sustained release of both 5P12-RANTES and dapivirine, in which the 5P12-RANTES is incorporated into an exposed core within the ring body and the dapivirine in the sheath. In this way, in vitro release of dapivirine matches closely that for Ring-004. Also, we report the pharmacokinetic testing of this combination ring formulation in sheep, where vaginal concentrations of both drugs are maintained over 28 days at levels potentially useful for preventing HIV infection in women.

Pharmaceutical Vehicles for Vaginal and Rectal Administration of Anti-HIV Microbicide Nanosystems

Prevention strategies play a key role in the fight against HIV/AIDS. Vaginal and rectal microbicides hold great promise in tackling sexual transmission of HIV-1, but effective and safe products are yet to be approved and made available to those in need. While most efforts have been placed in finding and testing suitable active drug candidates to be used in microbicide development, the last decade also saw considerable advances in the design of adequate carrier systems and formulations that could lead to products presenting enhanced performance in protecting from infection. One strategy demonstrating great potential encompasses the use of nanosystems, either with intrinsic antiviral activity or acting as carriers for promising microbicide drug candidates. Polymeric nanoparticles, in particular, have been shown to be able to enhance mucosal distribution and retention of promising antiretroviral compounds. One important aspect in the development of nanotechnology-based microbicides relates to the design of pharmaceutical vehicles that allow not only convenient vaginal and/or rectal administration, but also preserve or even enhance the performance of nanosystems. In this manuscript, we revise relevant work concerning the selection of vaginal/rectal dosage forms and vehicle formulation development for the administration of microbicide nanosystems. We also pinpoint major gaps in the field and provide pertinent hints for future work.

A Quantitative Disintegration Method for Polymeric Films

PURPOSE

Current in vitro disintegration methods for polymeric films are qualitative and introduce significant user bias. The goal of these studies is to develop a novel, quantitative disintegration technique which can be used to characterize polymeric films in vitro.

METHODS

A method was developed using a Texture Analyzer instrument to evaluate film disintegration. Solvent casted, clinically advanced, anti-HIV, vaginal films as well as marketed vaginal films were used throughout these studies. Method development followed a Quality by Design (QbD) process and was used to evaluate film products.

RESULTS

The current method developed provided reproducible, quantitative disintegration times for the commercially available Vaginal Contraceptive Film (57.88 ± 5.98 sec.). It distinguished between two clinically advanced antiretroviral containing films based on disintegration time (p value < 0.001); the tenofovir film (41.28 ± 3.35 sec.) and the dapivirine film (88.36 ± 10.61 sec.). This method could also distinguish between tenofovir and dapivirine films which had been altered in terms of volume (p<0.0001) and formulation (p<0.0001) based on disintegration time.

CONCLUSIONS

This method can be applied for pharmaceutical films for ranging indications as part of vigorous in vitro characterization. Parameters of the test can be altered based on site of application or indication.

Enzymatic Transition States and Drug Design

Transition state theory teaches that chemically stable mimics of enzymatic transition states will bind tightly to their cognate enzymes. Kinetic isotope effects combined with computational quantum chemistry provides enzymatic transition state information with sufficient fidelity to design transition state analogues. Examples are selected from various stages of drug development to demonstrate the application of transition state theory, inhibitor design, physicochemical characterization of transition state analogues, and their progress in drug development.

Perceptions of the "Fabric" - An exploratory study of a novel multi-purpose technology among women in Sub Saharan Africa

Background

HIV and pregnancy prevention are dual health priorities for women, and particularly in sub-Saharan Africa. Drug-eluting fibers offer a dosage form that combines HIV prevention and contraception, but early understanding of end-user perspectives is critical to avoid misalignment between products being developed and preferred product attributes.

Methods

Focus group discussions (FGDs) were conducted in South Africa, Uganda and Zimbabwe, among 55 women who had used vaginal products in previous trials. Participants were given the opportunity to feel a sample of electrospun nanofiber (the fabric), see how it dissolves, and give feedback on shape, size and other attributes. Women were also asked to compare the fabric to vaginal gel and film.

Results

Three key themes regarding the acceptability of the fabric emerged: 1) look and feel of the product undissolved vs. undissolved, 2) expected effect on sex, and 3) convenience and ease of use. Upon being presented with the fabric, women were initially distrustful, seeing it as undesirable for vaginal insertion. Women generally approved of the product once they saw it dissolve. However, they stressed the importance of the product not interfering with sex by altering the vaginal environment. Women also reacted favorably to the perceived convenience of the fabric, particularly with regards to storage and transport, perceived ease of insertion and use, and dosing regimen.

Conclusion

Multipurpose prevention technologies, and nanofibers in particular, should be developed with an eye to minimizing impact on sex while maximizing convenience, and presented in such a way as to emphasize non-abrasiveness and ease of dissolution.

Pharmaceutical Approaches to HIV Treatment and Prevention

Human immunodeficiency virus (HIV) infection continues to pose a major infectious disease threat worldwide. It is characterized by the depletion of CD4+ T cells, persistent immune activation, and increased susceptibility to secondary infections. Advances in the development of antiretroviral drugs and combination antiretroviral therapy have resulted in a remarkable reduction in HIV-associated morbidity and mortality. Antiretroviral therapy (ART) leads to effective suppression of HIV replication with partial recovery of host immune system and has successfully transformed HIV infection from a fatal disease to a chronic condition. Additionally, antiretroviral drugs have shown promise for prevention in HIV pre-exposure prophylaxis and treatment as prevention. However, ART is unable to cure HIV. Other limitations include drug-drug interactions, drug resistance, cytotoxic side effects, cost, and adherence. Alternative treatment options are being investigated to overcome these challenges including discovery of new molecules with increased anti-viral activity and development of easily administrable drug formulations. In light of the difficulties associated with current HIV treatment measures, and in the continuing absence of a cure, the prevention of new infections has also arisen as a prominent goal among efforts to curtail the worldwide HIV pandemic. In this review, the authors summarize currently available anti-HIV drugs and their combinations for treatment, new molecules under clinical development and prevention methods, and discuss drug delivery formats as well as associated challenges and alternative approaches for the future.

Griffithsin carrageenan fast dissolving inserts prevent SHIV HSV-2 and HPV infections in vivo

Human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) strategies with proven in vivo efficacy rely on antiretroviral drugs, creating the potential for drug resistance and complicated treatment options in individuals who become infected. Moreover, on-demand products are currently missing from the PrEP development portfolio. Griffithsin (GRFT) is a non-antiretroviral HIV entry inhibitor derived from red algae with an excellent safety profile and potent activity in vitro. When combined with carrageenan (CG), GRFT has strong activity against herpes simplex virus-2 (HSV-2) and human papillomavirus (HPV) in vitro and in vivo. Here, we report that GRFT/CG in a freeze-dried fast dissolving insert (FDI) formulation for on-demand use protects rhesus macaques from a high dose vaginal SHIV SF162P3 challenge 4 h after FDI insertion. Furthermore, the GRFT/CG FDI also protects mice vaginally against HSV-2 and HPV pseudovirus. As a safe, potent, broad-spectrum, on-demand non-antiretroviral product, the GRFT/CG FDI warrants clinical development.

Herpes simplex virus-binding IgG traps HSV in human cervicovaginal mucus across the menstrual cycle and diverse vaginal microbial composition

IgG possesses an important yet little recognized effector function in mucus. IgG bound to viral surface can immobilize otherwise readily diffusive viruses to the mucin matrix, excluding them from contacting target cells and facilitating their elimination by natural mucus clearance mechanisms. Cervicovaginal mucus (CVM) is populated by a microbial community, and its viscoelastic and barrier properties can vary substantially not only across the menstrual cycle, but also in women with distinct microbiota. How these variations impact the "muco-trapping" effector function of IgGs remains poorly understood. Here we obtained multiple fresh, undiluted CVM specimens (n = 82 unique specimens) from six women over time, and employed high-resolution multiple particle tracking to quantify the mobility of fluorescent Herpes Simplex Viruses (HSV-1) in CVM treated with different HSV-1-binding IgG. The IgG trapping potency was then correlated to the menstrual cycle, and the vaginal microbial composition was determined by 16 s rRNA. In the specimens studied, both polyclonal and monoclonal HSV-1-binding IgG appeared to consistently and effectively trap HSV-1 in CVM obtained at different times of the menstrual cycle and containing a diverse spectrum of commensals, including G. vaginalis-dominant microbiota. Our findings underscore the potential broad utility of this "muco-trapping" effector function of IgG to reinforce the vaginal mucosal defense, and motivates further investigation of passive immunization of the vagina as a strategy to protect against vaginally transmitted infections.

MIV-150 and zinc acetate combination provides potent and broad activity against HIV-1

We previously showed that the combination of the non-nucleoside reverse transcriptase inhibitor (NNRTI) MIV-150 with zinc acetate (ZA) formulated in a carrageenan (CG; MZC) gel provided macaques significant protection against vaginal simian-human immunodeficiency virus-RT (SHIV-RT) challenge, better than either MIV-150/CG or ZA/CG. The MZC gel was shown to be safe in a phase 1 clinical trial. Herein, we used in vitro approaches to study the antiviral properties of ZA and the MIV-150/ZA combination, compared to other NNRTIs. Like other NNRTIs, MIV-150 has EC₅₀ values in the subnanomolar to nanomolar range against wild type and NNRTI or RT-resistant HIVs. While less potent than NNRTIs, ZA was shown to be active in primary cells against laboratory-adapted and primary HIV-1 isolates and HIV-1 isolates/clones with NNRTI and RT resistance mutations, with EC₅₀ values between 20 and 110 μM. The MIV-150/ZA combination had a potent and broad antiviral activity in primary cells. In vitro resistance selection studies revealed that previously described NNRTI-resistant mutations were selected by MIV-150. ZA-resistant virus retained susceptibility to MIV-150 (and other RTIs) and MIV-150-selected virus remained sensitive to ZA. Notably, resistant virus was not selected when cultured in the presence of both ZA and MIV-150. This underscores the potency and breadth of the MIV-150/ZA combination, supporting preclinical macaque studies and the advancement of MZC microbicides into clinical testing.

Rhodanine derivatives as potent anti-HIV and anti-HSV microbicides

Although highly active antiretroviral therapies (HAART) remarkably increased life expectancy of HIV positive people, the rate of novel HIV-1 infections worldwide still represent a major concern. In this context, pre-exposure prophylaxis (PrEP) approaches such as vaginal microbicide gels topically releasing antiretroviral drugs, showed to have a striking impact in limiting HIV-1 spread. Nevertheless, the co-presence of other genital infections, particularly those due to HSV-1 or 2, constitute a serious drawback that strongly limits the efficacy of PrEP approaches. For this reason, combinations of different compounds with mixed antiviral and antiretroviral activity are thoroughly investigated Here we report the synthesis and the biological evaluation of a novel series of rhodanine derivatives, which showed to inhibit both HIV-1 and HSV-1/2 replication at nanomolar concentration, and were found to be active also on acyclovir resistant HSV-2 strains. The compounds showed a considerable reduction of activity in presence of serum due to a high binding to serum albumin, as determined through in vitro ADME evaluations. However, the most promising compound of the series maintained a considerable activity in gel formulation, with an EC50 comparable to that obtained for the reference drug tenofovir. Moreover, the series of compounds showed pharmacokinetic properties suitable for topical formulation, thus suggesting that the novel rhodanine derivatives could represent effective agents to be used as dual anti HIV/HSV microbicides in PrEP approaches.

A randomised trial of a contraceptive vaginal ring in women at risk of HIV infection in Rwanda: Safety of intermittent and continuous use

Background

Contraceptive vaginal rings could play a role in expanding the contraceptive method mix and in preparing communities for the introduction of HIV prevention and multipurpose rings.

Methods

We conducted an open label single-centre randomised clinical trial of intermittent versus continuous use of NuvaRing® in Kigali, Rwanda, in 2013–2014. We randomised 120 HIV-negative women 1:1 to intermittent use (three rings with a ring-free week in between rings) or continuous use (four rings without ring-free weeks). Women underwent an interview, counselling, and a speculum examination, and were tested for pregnancy, bacterial vaginosis (BV) by Nugent scoring, yeasts and trichomonads on wet mount, and sexually transmitted infections.

Findings

Only one woman withdrew early. Deliberate ring removals were rare, but spontaneous ring expulsions occurred during 14% of ring use periods. There were no incident pregnancies, serious adverse events, serious social harms, or early discontinuations for safety reasons. Systemic side effects were uncommon, and local side effects were not significantly differently distributed between groups except for lower abdominal pain (P = 0.013). The incidence of vaginal yeasts during ring use was high: 22% of intermittent users and 27% of continuous users had incident vaginal yeasts at one or multiple ring removal visits (P = 0.666), and symptomatic vaginal yeast cases were more common in the continuous than intermittent users (P = 0.031). In contrast, mean Nugent scores improved over time in both groups.

Conclusions

Intermittent and continuous NuvaRing® use were safe in Rwandan women and improved Nugent scores over time. However, attention should be paid to ring expulsions and to a potential increased risk of vaginal candidiasis.

A CCR5 antagonist-based HIV entry inhibitor exhibited potent spermicidal activity: Potential application for contraception and prevention of HIV sexual transmission

B07 is a small-molecule CCR5 antagonist-based HIV-1 entry inhibitor that is being developed as an anti-HIV microbicide for preventing sexual transmission of HIV. Here we evaluated its spermicidal and contraceptive potential, including sperm motility, plasma membrane integrity, and contraceptive efficacy tested in rabbits. We found that B07 inhibited sperm motility and movement patterns in a concentration- and time-dependent manner. Within 30 min, B07 induced sperm immobilization with the minimum 100% effective concentration and median effective concentration of 640.0 and 64.4 μg/mL, respectively. The hypo-osmotic swelling test showed that plasma membranes of B07-treated sperms exhibited slight disruption, as verified by electron micrographs. In both B07 gel and N-9 gel groups, not a single implantation site or embryo was observed based on the contraceptive efficacy test in rabbits, indicating that B07 could effectively block the potential of sperm to reach and/or fertilize oocytes. The safety profile of B07 in vivo was evaluated by use of an optimized rabbit vaginal irritation test. While the pathological scores of the N-9 gel group was 14.67 ± 1.21, those of the blank control and B07 gel groups were 2.17 ± 0.76 and 4.00 ± 0.89, respectively, which were within the clinically acceptable range (<8). The proportion of inflammatory cells and CD45⁺ cells in the cervicovaginal lavages of the B07 gel group showed no significant change compared to those of the control group. Therefore, our results confirmed that B07 exhibited significant spermicidal and contraceptive effects, suggesting its potential for development as a microbicidal spermicide for contraception and prevention of HIV sexual transmission.

Nanotechnologies for early diagnosis, in situ disease monitoring, and prevention

Nanotechnology is an enabling technology with great potential for applications in stem cell research and regenerative medicine. Fluorescent nanodiamond (FND), an inherently biocompatible and nontoxic nanoparticle, is well suited for such applications. We had developed a prospective isolation method using CD157, CD45, and CD54 to obtain lung stem cells. Labeling of CD45⁻CD54⁺CD157⁺ cells with FNDs did not eliminate their abilities for self-renewal and differentiation. The FND labeling in combination with cell sorting, fluorescence lifetime imaging microscopy, and immunostaining identified transplanted stem cells allowed tracking of their engraftment and regenerative capabilities with single-cell resolution. Time-gated fluorescence (TGF) imaging in mouse tissue sections indicated that they reside preferentially at the bronchoalveolar junctions of lungs, especially in naphthalene-injured mice. Our results presented in Subchapter 1.1 demonstrate not only the remarkable homing capacity and regenerative potential of the isolated stem cells, but also the ability of finding rare lung stem cells in vivo using FNDs.

The topical use of antiretroviral-based microbicides, namely of a dapivirine ring, has been recently shown to partially prevent transmission of HIV through the vaginal route. Among different formulation approaches, nanotechnology tools and principles have been used for the development of tentative vaginal and rectal microbicide products. Subchapter 1.2 provides an overview of antiretroviral drug nanocarriers as novel microbicide candidates and discusses recent and relevant research on the topic. Furthermore, advances in developing vaginal delivery platforms for the administration of promising antiretroviral drug nanocarriers are reviewed. Although mostly dedicated to the discussion of nanosystems for vaginal use, the development of rectal nanomicrobicides is also addressed.

Infectious diseases are currently responsible for over 8 million deaths per year. Efficient treatments require accurate recognition of pathogens at low concentrations, which in the case of blood infection (septicemia) can go as low as 1 mL^–1. Detecting and quantifying bacteria at such low concentrations is challenging and typically demands cultures of large samples of blood (∼1 mL) extending over 24–72 h. This delay seriously compromises the health of patients and is largely responsible for the death toll of bacterial infections. Recent advances in nanoscience, spectroscopy, plasmonics, and microfluidics allow for the development of optical devices capable of monitoring minute amounts of analytes in liquid samples. In Subchapter 1.3 we critically discuss these recent developments that will, in the future, enable the multiplex identification and quantification of microorganisms directly on their biological matrix with unprecedented speed, low cost, and sensitivity.

Radiolabeled nanoparticles (NPs) are finding an increasing interest in a broad range of biomedical applications. They may be used to detect and characterize diseases, to deliver relevant therapeutics, and to study the pharmacokinetic/pharmacodynamic parameters of nanomaterials. The use of radiotracer techniques in the research of novel NPs offers many advantages, but there are still some limitations. The binding of radionuclides to NPs has to be irreversible to prevent their escape to other tissues or organs. Due to the short half-lives of radionuclides, the manufacturing process is time limited and difficult, and there is also a risk of contamination. Subchapter 1.4 presents the main selection criteria for radionuclides and applicable radiolabeling procedures used for the radiolabeling of various NPs. Also, an overview of different types of NPs that have so far been labeled with radionuclides is presented.

An intravaginal ring that releases three antiviral agents and a contraceptive blocks SHIV-RT infection, reduces HSV-2 shedding, and suppresses hormonal cycling in rhesus macaques

Women globally need access to multipurpose prevention technologies (MPTs) that prevent human immunodeficiency virus (HIV), sexually transmitted infections that increase HIV acquisition/transmission risk, and unintended pregnancy. Seeking an MPT with activity against HIV, herpes simplex virus-2 (HSV-2), and human papillomavirus (HPV), we developed a prototype intravaginal ring (IVR), the MZCL IVR, which released the antiviral agents MIV-150, zinc acetate, and carrageenan (MZC for short) and the contraceptive levonorgestrel (LNG). Previously, we showed that an MZC gel has potent activity against immunodeficiency viruses, HSV-2, and HPV and that the MZCL (MZC with LNG) IVR releases all four components in macaques in vivo at levels associated with efficacy. Vaginal fluid from treated macaques has in vitro activity against HIV, HSV-2, and HPV. Herein, we assessed the ability of the MZCL IVR to protect macaques against repeated co-challenge with HSV-2 and SHIV-RT (simian immunodeficiency virus [SIV] containing the reverse transcriptase gene from HIV) and prevent hormonal cycling. We evaluated in vivo drug release in co-challenged macaques by measuring drug levels in blood and vaginal fluid and residual drug levels in used IVRs. The MZCL IVR significantly prevented SHIV-RT infection, reduced HSV-2 vaginal shedding, and prevented cycling. No non-nucleoside HIV reverse transcriptase inhibitor (NNRTI)-resistant SHIV was detected in macaques that became infected after continuous exposure to MZC from the IVR. Macaques wearing the MZCL IVR also had carrageenan levels in vaginal fluid expected to protect from HPV (extrapolated from mice) and LNG levels in blood associated with contraceptive efficacy. The MZCL IVR is a promising MPT candidate that warrants further development.

Attitudes and perceptions towards novel objective measures of ARV-based vaginal ring use: Results from a global stakeholder survey

Results of recent microbicide and pre-exposure prophylaxis clinical trials have shown adherence to be a significant challenge with new HIV prevention technologies. As the vaginal ring containing dapivirine moves into two open label follow-on studies (HOPE/MTN-025 and DREAM) and other antiretroviral-based and multi-purpose prevention technology ring products advance through the development pipeline, there is a need for more accurate and reliable measures of adherence to microbicide ring products. We previously conducted a comprehensive landscape analysis to identify new technologies that could be applied to adherence measurement of vaginal rings containing antiretrovirals. To explore attitudes and perceptions towards the approaches that we identified, we conducted a survey of stakeholders with experience and expertise in microbicide and HIV prevention clinical trials. From May to July 2015 an electronic survey was distributed via email to 894 stakeholders; a total of 206 eligible individuals responded to at least one question and were included in the data analysis. Survey respondents were presented with various objective measures and asked about their perceived acceptability to trial participants, feasibility of implementation by study staff, usefulness for measuring adherence and ethical concerns. Methods that require no additional input from the participant and require no modifications to the existing ring product (i.e., measurement of residual drug or excipient, or a vaginal analyte that enters the ring) were viewed as being more acceptable to trial participants and more feasible to implement in the field. Respondents saw value in using objective measures to provide real-time feedback on adherence. However, approaches that involve unannounced home visits for sample collection or spot checks of ring use, which could provide significant value to adherence feedback efforts, were met with skepticism. Additional research on the acceptability of these methods to potential trial participants and trial staff is recommended.

MZC Gel Inhibits SHIV-RT and HSV-2 in Macaque Vaginal Mucosa and SHIV-RT in Rectal Mucosa

The Population Council's microbicide gel MZC (also known as PC-1005) containing MIV-150 and zinc acetate dihydrate (ZA) in carrageenan (CG) has shown promise as a broad-spectrum microbicide against HIV, herpes simplex virus (HSV), and human papillomavirus. Previous data show antiviral activity against these viruses in cell-based assays, prevention of vaginal and rectal simian-human immunodeficiency virus reverse transcriptase (SHIV-RT) infection, and reduction of vaginal HSV shedding in rhesus macaques and also excellent antiviral activity against HSV and human papillomavirus in murine models. Recently, we demonstrated that MZC is safe and effective against SHIV-RT in macaque vaginal explants. Here we established models of ex vivo SHIV-RT/HSV-2 coinfection of vaginal mucosa and SHIV-RT infection of rectal mucosa in macaques (challenge of rectal mucosa with HSV-2 did not result in reproducible tissue infection), evaluated antiviral activity of MZC, and compared quantitative polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay readouts for monitoring SHIV-RT infection. MZC (at nontoxic dilutions) significantly inhibited SHIV-RT in vaginal and rectal mucosas and HSV-2 in vaginal mucosa when present during viral challenge. Analysis of SHIV-RT infection and MZC activity by 1-step simian immunodeficiency virus gag quantitative RT-PCR and p27 enzyme-linked immunosorbent assay demonstrated similar virus growth dynamics and MZC activity by both methods and higher sensitivity of quantitative RT-PCR. Our data provide more evidence that MZC is a promising dual compartment multipurpose prevention technology candidate.

First-in-Human Trial of MIV-150 and Zinc Acetate Coformulated in a Carrageenan Gel: Safety, Pharmacokinetics, Acceptability, Adherence, and Pharmacodynamics

OBJECTIVE

To evaluate the safety and pharmacokinetics of MIV-150 and zinc acetate in a carrageenan gel (PC-1005). Acceptability, adherence, and pharmacodynamics were also explored.

DESIGN

A 3-day open-label safety run-in (n = 5) preceded a placebo-controlled, double-blind trial in healthy, HIV-negative, abstinent women randomized (4:1) to vaginally apply 4 mL of PC-1005 or placebo once daily for 14 days.

METHODS

Assessments included physical examinations, safety labs, colposcopy, biopsies, cervicovaginal lavages (CVLs), and behavioral questionnaires. MIV-150 (plasma, CVL, tissue), zinc (plasma, CVL), and carrageenan (CVL) concentrations were determined with LC-MS/MS, ICP-MS, and ELISA, respectively. CVL antiviral activity was measured using cell-based assays. Safety, acceptability, and adherence were analyzed descriptively. Pharmacokinetic parameters were calculated using noncompartmental techniques and actual sampling times. CVL antiviral EC50 values were calculated using a dose-response inhibition analysis.

RESULTS

Participants (n = 20) ranged from 19-44 years old; 52% were black or African American. Among those completing the trial (13/17, PC-1005; 3/3, placebo), 11/17 reported liking the gel overall; 7 recommended reducing the volume. Adverse events, which were primarily mild and/or unrelated, were comparable between groups. Low systemic MIV-150 levels were observed, without accumulation. Plasma zinc levels were unchanged from baseline. Seven of seven CVLs collected 4-hour postdose demonstrated antiviral (HIV, human papillomavirus) activity. High baseline CVL anti-herpes-simplex virus type-2 (HSV-2) activity precluded assessment of postdose activity.

CONCLUSIONS

PC-1005 used vaginally for 14 days was well tolerated. Low systemic levels of MIV-150 were observed. Plasma zinc levels were unchanged. Postdose CVLs had anti-HIV and anti-human papillomavirus activity. These data warrant further development of PC-1005 for HIV and sexually transmitted infection prevention.

Contraceptive Practice in Sub-Saharan Africa

Forty eight of the African continent's 54 sovereign states are located in the Sub-Saharan Africa (SSA) region, with the government of each defining and shaping its own health services and delivery systems. This paper reviews the trends and patterns of contraceptive practice in the region. Using survey data available from the Demographic and Health Surveys and Performance Monitoring and Accountability 2020, the study finds modern contraceptive practice to be on the rise overall but with much geographic variation. The contraceptive methods most frequently used are injectables and, more recently, implants. Higher levels of use are observed among unmarried sexually active than married females. Although use is rising, contraceptive discontinuation rates are also high. Recent program initiatives discussed include expanding long-acting contraceptive options, promoting and delivering contraceptive methods in the postpartum period, and relying on community health workers for contraceptive outreach and service delivery. SSA's family planning situation remains challenged by weak health systems which must address competing priorities to manage disease prevention as well as primary health care. Increasing investments in family planning delivery in many SSA countries, however, augur for continued rapid uptake of modern contraception, possibly matching if not outpacing the record of other regions.

In Vitro Exposure to PC-1005 and Cervicovaginal Lavage Fluid from Women Vaginally Administered PC-1005 Inhibits HIV-1 and HSV-2 Infection in Human Cervical Mucosa

Our recent phase 1 trial demonstrated that PC-1005 gel containing 50 μM MIV-150, 14 mM zinc acetate dihydrate, and carrageenan (CG) applied daily vaginally for 14 days is safe and well tolerated. Importantly, cervicovaginal lavage fluid samples (CVLs) collected 4 or 24 h after the last gel application inhibited HIV-1 and human papillomavirus (HPV) in cell-based assays in a dose-dependent manner (MIV-150 for HIV-1 and CG for HPV). Herein we aimed to determine the anti-HIV and anti-herpes simplex virus 2 (anti-HSV-2) activity of PC-1005 in human cervical explants after in vitro exposure to the gel and to CVLs from participants in the phase 1 trial. Single HIV-1BaL infection and HIV-1BaL-HSV-2 coinfection explant models were utilized. Coinfection with HSV-2 enhanced tissue HIV-1BaL infection. In vitro exposure to PC-1005 protected cervical mucosa against HIV-1BaL (up to a 1:300 dilution) in single-challenge and cochallenge models. CG gel (PC-525) provided some barrier effect against HIV-1BaL at the 1:100 dilution in a single-challenge model but not in the cochallenge model. Both PC-1005 and PC-525 at the 1:100 dilution inhibited HSV-2 infection, pointing to a CG-mediated protection. MIV-150 and CG in CVLs inhibited HIV (single-challenge or cochallenge models) and HSV-2 infections in explants in a dose-dependent manner (P < 0.05). Stronger inhibition of HIV-1 infection by CVLs collected 4 h after the last gel administration was observed compared to infection detected in the presence of baseline CVLs. The anti-HIV and anti-HSV-2 activity of PC-1005 gel in vitro and CVLs in human ectocervical explants supports the further development of PC-1005 gel as a broad-spectrum on-demand microbicide.

Nanomedicine in the development of anti-HIV microbicides

Prevention plays an invaluable role in the fight against HIV/AIDS. The use of microbicides is considered an interesting potential approach for topical pre-exposure prophylaxis of HIV sexual transmission. The prospects of having an effective product available are expected to be fulfilled in the near future as driven by recent and forthcoming results of clinical trials. Different dosage forms and delivery strategies have been proposed and tested for multiple microbicide drug candidates presently at different stages of the development pipeline. One particularly interesting approach comprises the application of nanomedicine principles to the development of novel anti-HIV microbicides, but its implications to efficacy and safety are not yet fully understood. Nanotechnology-based systems, either presenting inherent anti-HIV activity or acting as drug nanocarriers, may significantly influence features such as drug solubility, stability of active payloads, drug release, interactions between active moieties and virus/cells, intracellular drug delivery, drug targeting, safety, antiviral activity, mucoadhesive behavior, drug distribution and tissue penetration, and pharmacokinetics. The present manuscript provides a comprehensive and holistic overview of these topics as relevant to the development of vaginal and rectal microbicides. In particular, recent advances pertaining inherently active microbicide nanosystems and microbicide drug nanocarriers are discussed.