The combined contraceptive vaginal ring, NuvaRing: an international study of user acceptability

Safety and acceptability of intravaginal rings releasing estradiol and progesterone

OBJECTIVE

This study aimed to evaluate the safety and acceptability of two fixed-dose 28-day vaginal ring formulations of 17β-estradiol (E2) and progesterone (P4) to treat vasomotor symptoms (VMS) and the genitourinary syndrome of menopause.

DESIGN

DARE HRT1-001 was the first-in-woman study of 28-day exposure to two 28-day intravaginal rings (IVRs) designed to release 80 µg/day E2 + 4 mg/day P4 (IVR1) or 160 µg/day E2 + 8 mg/day P4 (IVR2) compared with oral E2 1 mg/day + oral P4 100 mg/day. To assess safety, participants completed a daily diary to record treatment emergent adverse events (TEAEs). To determine acceptability, at the end of treatment IVR users completed a questionnaire assessing tolerability and usability.

RESULTS

Enrolled women (n = 34) were randomized to use IVR1 (n = 10), IVR2 (n = 12) or oral (n = 12). Thirty-one participants (IVR1 = 10, IVR2 = 10, oral = 11) completed the study. The TEAE profile of those in the IVR groups were similar to the referent oral regimen. TEAEs related to the study product were more common with IVR2 use. Endometrial biopsies were not performed unless endometrial thickness was >4 mm or for clinically significant postmenopausal bleeding. One IVR1 participant had an endometrial stripe increase from 4 mm at screening to 8 mm at the end of treatment. The biopsy indicated no evidence of plasma cells or endometritis and no evidence of atypia, hyperplasia or malignancy. Two other endometrial biopsies were performed for postmenopausal bleeding with similar findings. There were no clinically meaningful laboratory or vital sign abnormalities or trends identified in observed values or changes from baseline. Pelvic speculum examination identified no clinically significant abnormalities in any participant at any visit. Tolerability and usability data demonstrated that both IVRs were generally highly acceptable.

CONCLUSIONS

Both IVR1 and IVR2 were safe and well tolerated in healthy postmenopausal women. TEAE profiles were comparable to the referent oral regimen.

Three-Dimensionally Printed Vaginal Rings: Perceptions of Women and Gynecologists in a Cross-Sectional Survey

Three-dimensional printing technologies can be implemented for the fabrication of personalized vaginal rings (VRs) as an alternative approach to traditional manufacturing. Although several studies have demonstrated the potential of additive manufacturing, there is a lack of knowledge concerning the opinions of patients and clinicians. This study aimed to investigate the perception of women and gynecologists regarding VRs with personalized shapes. The devices were printed with different designs (traditional, "Y", "M", and flat circle) by Fused Deposition Modeling for a cross-sectional survey with 155 participants. Their anticipated opinion was assessed through a questionnaire after a visual/tactile analysis of the VRs. The findings revealed that most women would feel comfortable using some of the 3D-printed VR designs and demonstrated good acceptability for the traditional and two innovative designs. However, women presented multiple preferences when the actual geometry was assessed, which directly related to their age, previous use of the vaginal route, and perception of comfort. In turn, gynecologists favored prescribing traditional and flat circle designs. Overall, although there was a difference in the perception between women and gynecologists, they had a positive opinion of the 3D-printed VRs. Finally, the personalized VRs could lead to an increase in therapeutic adherence, by meeting women's preferences.

Participant experiences with a multipurpose vaginal ring for HIV and pregnancy prevention during a phase 1 clinical trial: learning from users to improve acceptability

Introduction

With high concurrent global rates of HIV incidence and unintended pregnancy, there is a need to provide options beyond condoms to enable users to simultaneously prevent HIV acquisition and pregnancy. Multiple vaginal rings are in development as "MPTs" (multipurpose prevention technologies) as they are shown to provide several co-occurring benefits such as discretion, convenience, reversibility and user control.

Methods

In this Phase 1 trial of a 3-month MPT ring in the U.S., 25 participants (low-risk for HIV and pregnancy) were randomized to use the study ring for 90 days continuously or in 28-day cycles with 2-day removal periods in between. All participants completed in-depth interviews at the end of their study participation.

Results

Overall, the ring was well tolerated. Participants resoundingly endorsed the concept of an extended-use, dual-purpose vaginal ring, but reported too many functional challenges and side effects to endorse this particular ring. Participants assigned to the continuous regimen reported more positive experiences with ring use than those in the cyclic group. A minority of participants who experienced minimal side effects and did not experience challenges with vaginal retention of the ring found it appealing. However, the majority of participants experienced challenges (ring slippage, expulsions, side effects, vaginal bleeding changes) with product use that outweighed the potential benefits and led them to report that - in the future - they would not be interested in using this specific version of the ring in its current form. A subset expressed interest in using the current MPT ring under certain conditions (e.g., if fewer expulsions, less bleeding, higher risk for HIV/pregnancy).

Discussion

User feedback regarding participant experiences and challenges with the study ring was continuously shared with the product developer, underscoring the value of early-stage end-user feedback in product development.

Satisfaction with a Segesterone Acetate and Ethinyl Estradiol Contraceptive Vaginal System Among Recent Oral Contraceptive or Hormonal Contraceptive Vaginal Ring Users

Background: We evaluated satisfaction with use of a segesterone acetate and ethinyl estradiol (0.15/0.013 mg) contraceptive vaginal system (CVS) among women who had recently used a monthly contraceptive vaginal ring or contraceptive pills. The CVS is a ring-shaped device used in a 21-days-in/7-days-out regimen for 13 cycles. Materials and Methods: We analyzed post hoc satisfaction responses at cycle 3 and end of study (EOS) from a subset of participants with documented recent use of the monthly ring or daily pills before enrollment in a multinational, phase 3, 13-cycle trial evaluating the CVS. EOS included results from participants who had completed ≥10 cycles. Results were summarized descriptively. Results: We identified 128 recent ring and 219 recent pill users at cycle 3 (of 1033 survey participants), and 92 and 148, respectively, at EOS (of 622 survey participants); overall satisfaction with CVS use was high (≥90%). At EOS, most ring (89%) and pill (97%) users liked the CVS as much/better than any previous method. The two most-liked CVS features included ease of use and 1-year duration; the two most disliked features included ring insertion and feeling it coming out. At EOS, ≥88% of both groups reported no concern about using the same CVS for a year, and most (>80%) had recommended it to friends or family members. Conclusion: The CVS clinical trial participants who were recent ring/pill users reported high satisfaction and liked it as much/better than any previously used contraceptive; the CVS may be a good contraceptive option for switchers. Clinical trial registration NCT00263341.

Effects of the Combined Contraceptive Vaginal Ring on Female Sexual Function: A Systematic Review and Meta-analysis

There are controversial debates regarding the effects of contraceptive vaginal ring devices on females' sexual function. Therefore, the meta-analysis of before-after was conducted on the intervention studies published in the past years to clarify these contradictions. The existing literature on the subject was reviewed by searching through such databases as PubMed, Scopus, ISI Web of Sciences, Embase, Cochrane Library and Google Scholar up to July 2021. Before-after intervention studies that had examined the effect of vaginal rings on females' sexual function were collected as well. In total, five studies with 369 participants were included in quantitative syntheses. Pooled results from the random-effect model showed that NuvaRing had a positive effect on females' sexual function three months after insertion (WMD: 2.48; 95% CI: 0.30, 4.67; P = 0.026); however, this effect was not significant after 6 months (WMD: 4.38; 95% CI: -4.95, 13.72; P = 0.357). Meta-regression analysis suggested that the effect of this device is associated with users' age and body mass index 3 months after insertion. No publication bias was found by Egger's test or funnel plots. Overall, the results of this meta-analysis support the view that vaginal ring use is associated with a positive effect on the sexual function of women 3 months after insertion, while the effect of this device on the sexual function of women was insignificant after 6 months. However, given the dearth of available data, it is not possible to reach a definite conclusion on the effect of vaginal rings on females' sexual function.

3D-Printed EVA Devices for Antiviral Delivery and Herpes Virus Control in Genital Infection

Herpes viruses are widespread in the human population and can cause many different diseases. Genital herpes is common and can increase the risk of HIV infection and neonatal herpes. Acyclovir is the most used drug for herpes treatment; however, it presents some disadvantages due to its poor oral bioavailability. In this study, some ethylene vinyl acetate devices with different acyclovir amounts (0, 10, and 20 wt.%) were manufactured by fused filament fabrication in two different geometries, an intrauterine device, and an intravaginal ring. Thermal analyses suggested that the crystallinity of EVA decreased up to 8% for the sample loaded with 20 wt.% of acyclovir. DSC, SEM, and FTIR analyses confirmed that the drug was successfully incorporated into the EVA matrix. Moreover, the drug release tests suggested a burst release during the first 24 h followed by a slower release rate sustained up to 80 days. Biological assays showed the biocompatibility of the EVA/ACV device, as well as a 99% reduction in vitro replication of HSV-1. Finally, the EVA presented a suitable performance for 3D printing manufacturing that can contribute to developing personalized solutions for long-term herpes treatment.

Non-oral routes, novel formulations and devices of contraceptives: An update

Family planning enables society to prevent unintended pregnancies and helps in attaining desired spacing between the pregnancies. It is done with the use of contraceptive methods and infertility treatments. The use of contraceptives serves to ease maternal ill-health and reduce pregnancy-related deaths and helps to decrease the number of unsafe abortions and HIV transmission from mothers to newborns. The most popular contraception method is a daily dose of combined oral contraceptives pills. However, poor compliance and various adverse effects are common problems of oral contraceptives that considerably reduce their long-term use. Thus, several non-oral contraceptive options have been developed for better compliance, reduced side effects and improved therapeutic efficacy. This review presented the non-oral contraceptive formulations given by different routes such as transdermal, nasal, subcutaneous, intramuscular, intrauterine and vaginal routes. These formulations delivering contraceptives, mainly through devices, include transdermal patches and microneedles, nasal sprays, intrauterine devices and intrauterine systems, vaginal rings, contraceptive implants and contraceptive injections, which are unique in their specific advantages and drawbacks.

Women's preferences and acceptance for different drug delivery routes and products

To use or not to use, that is the first decision to take regarding a drug product. This mandatory step for adherence dictates product efficacy. The determinants for such decision do not only rely on the priority of the therapeutic or preventive strategy, but are related to a complex network of perceptions, preferences, personal and cultural backgrounds, and results from previous experiences. Women's preferences for dosage forms and even for drug delivery routes have been mainly studied in the fields of contraception and HIV prevention (and their related multipurpose approaches). Much less attention has been devoted to other therapeutic or preventive strategies. In a time when patient-centred approaches and shared decisions are increasingly valued, considering women's preferences and their main determinants is essential for product development and selection. Such products will be more likely to be chosen and used as intended, increasing efficacy, and reducing the overall costs related with these treatments. This knowledge shall be integrated in early stages of product development. This article reviews the state of the art related with women's preferences and acceptance for different dosage forms and drug delivery routes involved in women's health. The methodologies used for collecting these data and their major drawbacks are discussed. Results obtained from acceptability studies and the main determinants for selection of preventive and treatment drug products are discussed as tools for new developments in the field.

Acceptability and Satisfaction of Contraceptive Vaginal Rings in Clinical Studies: A Systematic Review and Narrative Synthesis

Introduction: Acceptability of and satisfaction with contraceptive methods are paramount for uptake and continuation. In the current context of multipurpose prevention of pregnancy and sexually transmitted diseases/HIV development, it is critical to have a better understanding of acceptability of and satisfaction with the contraceptive vaginal ring (CVR) including sexual satisfaction. The objective of this study was to review the evidence about acceptability of CVRs and general and sexual satisfaction of users. Methods: We searched PubMed, CINAHL, and Web of Science (until December 31, 2020) and selected original studies documenting actual use of hormonal CVR and explicitly addressing any of the 3 outcomes. Results: Of a total of 1,129 records screened, 46 studies were included. Most studies (n = 43, 93%) were prospective, conducted in high-income settings (n = 35), and reported on NuvaRing^® use (n = 31). Overall, 27 (59%) studies included a comparison group, 38 (82%) studies used exclusively quantitative questionnaires, with qualitative only (n = 4, 9%), or mixed methods (n = 4, 9%) studies being less common. Ease of CVR insertion/removal/reinsertion was high in all the settings and improved with time of use, with qualitative studies supporting these findings. When mentioned, ring-related events were associated with discontinuation, and results on continuation of use were mixed. Among NuvaRing^® studies, general satisfaction (being satisfied or very satisfied) was between 80 and 90% and tended to mirror continuation. Sexual satisfaction was less commonly reported and results were mixed. Overall, limited information was provided on actual CVR experiences of women (and men) and cultural norms that may affect sexuality and CVR use. Conclusion: Positive aspects of acceptability of and satisfaction with CVRs were reported, but ring-related events and factors, which may affect long-term CVR use, deserve further study. More information is needed on actual experiences of women using CVRs, relationship aspects, male partner opinions, and contextual norms to better understand the acceptability of and satisfaction with CVRs.

Development of Hormonal Intravaginal Rings: Technology and Challenges

Intravaginal rings (IVRs) are minimally invasive polymeric devices specifically designed to be used for the sustained and prolonged release of various type of drugs such as hormones. One of the benefits of using topical drug delivery systems (e.g., IVRs) is the fact that systemic drug delivery may cause drug resistance due to elevated drug levels. Topical drug delivery also provides higher concentrations of the drug to the target site and has fewer side effects. In addition, when a drug is administered vaginally, the hepatic first-pass effect is avoided, resulting in higher absorption. Contraception and treatments for specific diseases such as endometriosis and hormone deficiencies can be improved by the administration of hormones via an IVR. This article aims to classify and compare various designs of commercially available and non-commercial hormonal IVRs and to analyze their performance. Current challenges affecting the development of IVRs are investigated, and proposed solutions are discussed. A comprehensive search of publications in MEDLINE/PubMed and of commercial product data of IVRs was performed, and the materials, designs, performance, and applications (e.g., contraception, endometriosis, estrogen deficiency and urogenital atrophy) of hormonal IVRs were thoroughly evaluated. Most hormonal IVRs administer female sex hormones, i.e., estrogen and progestogens. In terms of material, IVRs are divided into 3 main groups: silicone, polyurethane, and polyethylene-co-vinyl acetate IVRs. As regards their design, there are 4 major designs for IVRs which strongly affect their performance and the timing and rate of hormone release. Important challenges include reducing the burst release and maintaining the bioavailability of hormones at their site of action over a prolonged period of administration as well as lowering production costs. Hormonal IVRs are a promising method which could be used to facilitate combination therapies by administering multiple drugs in a single IVR while eliminating the side effects of conventional drug administration methods. IVRs could considerably improve womenʼs quality of life all over the world within a short period of time.

Use of simulated vaginal and menstrual fluids to model in vivo discolouration of silicone elastomer vaginal rings

Vaginal rings releasing antiretrovirals – either alone or in combination with contraceptive progestins – are being developed for prevention of human immunodeficiency virus (HIV) transmission via vaginal sex. Following Phase I trials, significant discolouration was observed on the surface of investigational silicone elastomer antiretroviral-contraceptive matrix-type vaginal rings containing either 25 mg dapivirine or 200 mg dapivirine plus levonorgestrel. In this study, potential causes of the discolouration have been assessed in vitro using simulated vaginal and menstrual fluids (SVF and SMF, respectively) to model in vivo exposure. The fluid compositions also included hydrogen peroxide (H₂O₂), hydrogen peroxide plus a copper intrauterine device (IUD), or synthetic dyes (representing personal care and household cleaning products). No discolouration was observed for rings exposed to SVF + hydrogen peroxide (with or without an IUD). However, the SVF + dye compositions showed significant ring discolouration, with staining patterns similar to those observed with rings that had been exposed to highly-coloured personal care and household cleaning products during clinical trial use. Exposure of rings to SMF compositions invariably caused yellow surface discolouration, dark spotting and markings, similar to the staining patterns observed following clinical use. The darker marks on the ring surface were identified as blood debris derived from the SMF. The study indicates that surface discolouration of rings in vivo can be attributed to exposure to menstrual fluid or highly coloured personal care or household cleaning products. Discolouration of the rings was not associated with any specific safety risks for the user, though severe discolouration could potentially impact acceptability and adherence.

Segmented intravaginal ring for the combination delivery of hydroxychloroquine and anti-CCR5 siRNA nanoparticles as a potential strategy for preventing HIV infection

Abstract 

Vaginal drug delivery has been shown to be a promising strategy for the prevention of sexually transmitted infections. Therapy delivered at the site of infection has many advantages including improved therapeutic efficacy, reduction in systemic toxicity, and reduced potential for development of drug resistance. We developed a “smart” combination intravaginal ring (IVR) that will (1) provide continuous release of hydroxychloroquine (HCQ) to induce T cell immune quiescence as the first-line of defense and (2) release nanoparticles containing anti-CCR5 siRNA only during sexual intercourse when triggered by the presence of seminal fluid as the second-line of defense. The IVR was capable of releasing HCQ over 25 days with a mean daily release of 31.17 ± 3.06 µg/mL. In the presence of vaginal fluid simulant plus seminal fluid simulant, over 12 × more nanoparticles (5.12 ± 0.9 mg) were released over a 4-h period in comparison to IVR segments that were incubated in the presence of vaginal fluid simulant alone (0.42 ± 0.19 mg). Anti-CCR5 siRNA nanoparticles were able to knockdown 83 ± 5.1% of CCR5 gene expression in vitro in the CD4⁺ T cell line Sup-T1. The IVR system also demonstrated to be non-cytotoxic to VK2/E6E7 vaginal epithelial cells.

Graphical abstract

Acceptability of a Tenofovir Disoproxil Fumarate Intravaginal Ring for HIV Pre-Exposure Prophylaxis Among Sexually Active Women

INTRODUCTION

Vaginal ring delivery of antiretroviral drugs may provide protection against acquisition of HIV-1 when used as Pre-Exposure prophylaxis. As part of a randomized placebo-controlled safety trial of a tenofovir disoproxil fumarate (TDF) intravaginal ring (IVR), we assessed product acceptability through surveys of women after continuous ring use.

METHODS

Sexually active, HIV-negative women were enrolled to investigate the safety and pharmacokinetics of 3 months of continuous TDF IVR use. The study was designed to include 40 US participants randomly assigned (3:1) to a TDF or placebo IVR. Twelve were randomized to TDF and 5 to the placebo group before the study was electively discontinued because of the development of vaginal ulcerations in 8 women in the TDF group. Acceptability data were gathered via self-administered, computer-based questionnaires.

RESULTS

The average age of the 17 participants was 31 years (range, 18-42 years). Sixteen participants (94%) completed all questions at 2 study visits. When asked about ring likeability after 1 month of ring use, 12 (75%) of 16 reported overall liking the ring, including 6 (75%) of 8 who developed ulcerations. In addition, 10 (83%) of 12 who had their menses during the first month of ring use were not bothered by the ring, and 11 (69%) of 16 stated that the ring was not bothersome with use during sex.

CONCLUSIONS

Despite unanticipated ulcers, TDF and placebo IVRs were acceptable to some women, even when used with menses and during sex, which is promising for continued development of IVRs for HIV prevention.

Vaginal Administration of Contraceptives

While contraceptive drugs have enabled many people to decide when they want to have a baby, more than 100 million unintended pregnancies each year in the world may indicate the contraceptive requirement of many people has not been well addressed yet. The vagina is a well-established and practical route for the delivery of various pharmacological molecules, including contraceptives. This review aims to present an overview of different contraceptive methods focusing on the vaginal route of delivery for contraceptives, including current developments, discussing the potentials and limitations of the modern methods, designs, and how well each method performs for delivering the contraceptives and preventing pregnancy.

Influence of Polymer Composition on the Controlled Release of Docetaxel: A Comparison of Non-Degradable Polymer Films for Oesophageal Drug-Eluting Stents

Following the huge clinical success of drug-eluting vascular stents, there is a significant interest in the development of drug-eluting stents for other applications, such as the treatment of gastrointestinal (GI) cancers. Central to this process is understanding how particular drugs are released from stent coatings, which to a large extent is controlled by drug-polymer interactions. Therefore, in this study we investigated the release of docetaxel (DTX) from a selection of non-degradable polymer films. DTX-polymer films were prepared at various loadings (1, 5 and 10% w/w) using three commercially available polymers including poly(dimethylsiloxane) (PSi), poly (ethylene-co-vinyl acetate) (PEVA) and Chronosil polyurethane (PU). The formulations were characterised using different techniques such as photoacoustic Fourier-transform infrared (PA-FTIR) spectrophotometry, X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The effect of DTX on the mechanical properties of the films, in-vitro release, and degradation tests were also assessed. For all polymers and DTX loadings, the drug was found to disperse homogenously without crystallisation within the polymer matrix. While no specific interactions were observed between DTX and PSi or PEVA, hydrogen-bonding appeared to be present between DTX and PU, which resulted in a concentration-dependent decrease in the Young’s moduli of the films due to disruption of inter-polymeric molecular interactions. In addition, the DTX-PU interactions were found to modulate drug release, providing near-linear release over 30 days, which was accompanied by a significant reduction in degradation products. The results indicate that DTX-loaded PU films are excellent candidates for drug-eluting stents for the treatment of oesophageal cancer.

Rational Design of a Multipurpose Bioadhesive Vaginal Film for Co-Delivery of Dapivirine and Levonorgestrel

Human immunodeficiency virus (HIV) infection and unintended pregnancy, which can lead to life-threatening complications, are two major burdens for female reproductive health. To address these pressing health issues, multipurpose prevention technologies (MPTs) are proposed to deliver two or more drugs simultaneously. MPTs could offer several benefits for users such as improved convenience, increased effectiveness, reduced cost, and decreased environmental burden. Here, we report the development, and in vitro and in vivo assessment of a bioadhesive vaginal film as a coitally-independent MPT dosage form for delivering dapivirine (DPV) and levonorgestrel (LNG) to prevent HIV infection and unintended pregnancy, respectively. After confirming the feasibility of bioadhesive film use for weekly drug delivery in vivo through colpophotography and MRI evaluation, the pharmacokinetics (PK) of DPV/LNG single entity and combination bioadhesive films was investigated in pigtailed macaques (n = 5). Both drugs from single entity or combination films were able to provide sustained drug release in vivo. The combination film showed lower local tissue clearance for DPV and exhibited significantly increased plasma concentration for LNG as compared to the single entity film. This proof-of-concept study demonstrates the ability of this novel bioadhesive film platform to deliver LNG and DPV simultaneously as an MPT product for the prevention of HIV infection and unintended pregnancy.

Development of an intravaginal ring delivering simultaneously anastrozole and levonorgestrel: a pharmacokinetic perspective

Intravaginal rings (IVRs) are an option for continuous administration of drugs in women. As an attractive approach for the treatment of endometriosis-associated pelvic pain, IVRs delivering a combination of the aromatase inhibitor anastrozole (ATZ) and the progestin levonorgestrel (LNG) have been developed. This article describes the developmental pharmacokinetic (PK) aspects covering the characterization of in vitro release, preclinical IVR PK investigations in monkeys, and clinical PK considerations. An IVR for ATZ has been developed and investigated in healthy menstruating female cynomolgus monkeys showing effective in vivo release. PK data from the size-adapted IVR used in these animals can be translated into a human context as confirmed in human studies where predefined exposure levels of ATZ were reached. As ATZ may cause harm to the fetus, use of effective contraception has to be assured in women of childbearing potential. Therefore, the IVR delivers a low dose of LNG as a contraceptive. Although the daily dose differed strongly between both drugs (20 µg LNG/d to >1 mg ATZ/d), simultaneous delivery of ATZ and LNG in vitro and in vivo was observed with a high correlation between the in vitro release and PK profiles. The PK characteristics successfully guided the design of clinical studies investigating the drug–drug interaction (DDI) potential. No relevant DDI between both the investigated or other vaginally administered drugs were identified.

Vaginal ring acceptability and related preferences among women in low- and middle-income countries: A systematic review and narrative synthesis

The vaginal ring (VR) is a female-initiated drug-delivery platform used for different indications, including HIV pre-exposure prophylaxis (PrEP). We conducted a systematic review of VR acceptability, values and preferences among women in low- and middle-income countries (LMIC) to inform further investment and/or guidance on VR use for HIV prevention. Following PRISMA guidelines, we used structured methods to search, screen, and extract data from randomized controlled trials (RCTs) and observational studies reporting quantitative outcomes of acceptability of the VR for any indication published 1/1970-2/2019 (PROSPERO: CRD42019122220). Of 1,110 records identified, 68 met inclusion criteria. Studies included women 15-50+ years from 25 LMIC for indications including HIV prevention, contraception, abnormal bleeding, and menopause. Overall VR acceptability was high (71-98% across RCTs; 62-100% across observational studies), with 80-100% continuation rates in RCTs and favorable ease of insertion (greater than 85%) and removal 89-99%). Users reported concerns about the VR getting lost in the body (8-43%), although actual expulsions and adverse events were generally infrequent. Most women disclosed use to partners, with some worrying about partner anger/violence. The VR was not felt during intercourse by 70-92% of users and 48-97% of partners. Acceptability improved over time both within studies (as women gained VR experience and worries diminished), and over chronological time (as the device was popularized). Women expressed preferences for accessible, long-acting, partner-approved methods that prevent both HIV and pregnancy, can be used without partner knowledge, and have no impact on sex and few side effects. This review was limited by a lack of standardization of acceptability measures and study heterogeneity. This systematic review suggests that most LMIC women users have a positive view of the VR that increases with familiarity of use; and, that many would consider the VR an acceptable future delivery device for HIV prevention or other indications.

Topical Inserts: A Versatile Delivery Form for HIV Prevention

The development of topical inserts for the prevention of sexually transmitted infections (STIs), particularly human immunodeficiency virus (HIV), represents a promising alternative to oral and parenteral pre-exposure prophylaxis (PrEP) dosage forms. They may be used for vaginal and/or rectal administration of a variety of agents with antiviral activity. Topical inserts deliver drugs to the portal of viral entry, i.e., the genital or rectal mucosa, with low systemic exposure, and therefore are safer and have fewer side effects than systemic PrEP agents. They may dissolve fast, releasing the active drugs within minutes of insertion, or slowly for long-acting drug delivery. Furthermore, they are user-friendly being easy to administer, discreet and highly portable. They are also economical and easy to manufacture at scale and to distribute, with excellent stability and shelf-life. Altogether, topical inserts represent a particularly promising form of drug delivery for HIV and STI prevention. Highlighted within this review are end-user acceptability research dedicated to understanding preferred attributes for this form of drug delivery, advantages and disadvantages of the formulation platform options, considerations for their development, clinical assessment of select placebo prototypes, future directions, and the potential impact of this dosage form on the HIV prevention landscape.

No. 329-Canadian Contraception Consensus Part 4 of 4 Chapter 9: Combined Hormonal Contraception

OBJECTIVE

To provide guidelines for health care providers on the use of contraceptive methods to prevent pregnancy and on the promotion of healthy sexuality.

OUTCOMES

Overall efficacy of cited contraceptive methods, assessing reduction in pregnancy rate, safety, and side effects; the effect of cited contraceptive methods on sexual health and general well-being; and the availability of cited contraceptive methods in Canada.

EVIDENCE

Medline and the Cochrane Database were searched for articles in English on subjects related to contraception, sexuality, and sexual health from January 1994 to December 2015 in order to update the Canadian Contraception Consensus published February-April 2004. Relevant Canadian government publications and position papers from appropriate health and family planning organizations were also reviewed.

VALUES

The quality of the evidence is rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice are ranked according to the method described in this report.

SUMMARY STATEMENTS

RECOMMENDATIONS.

High acceptability of a contraceptive vaginal ring among women in Kigali, Rwanda

BACKGROUND

Introduction of contraceptive vaginal rings (CVRs) could expand the contraceptive method mix reducing the unmet need for family planning in Rwanda, but data on acceptability of CVRs from low and middle-income countries are lacking.

METHODS

This study explores acceptability of contraceptive vaginal ring (NuvaRing) use in Kigali, Rwanda using a mixed methods approach. We collected quantitative and qualitative data before, during and after conducting a clinical trial, using Case Report Forms, Interviewer Administered Questionnaires, In Depth Interviews and Focus Group Discussions. We analyzed the data using an existing theoretical framework including product attributes, relationship attributes and sexual encounter attributes as well as the contextual environment.

RESULTS

Our data showed that initial worries reduced over time with actual ring use and ring insertions and removals were described as easy. Most women did not feel the ring during daily activities, appreciated the lack of perceived negative side effects and the increased lubrication. Relationship attributes and sexual encounter attributes such as sexual comfort played a significant role in ring acceptability of the participants and their partners. The contextual environment including Rwandan cultural norms around sexuality positively influenced the acceptance of the NuvaRing. Overall satisfaction was high.

CONCLUSIONS

Acceptability of the Nuvaring was high among study participants and represents a promising option that could contribute to lowering the unmet need for family planning in Rwanda.

Acceptability of a Tenofovir Disoproxil Fumarate Vaginal Ring for HIV Prevention Among Women in New York City

Vaginal rings for pre-exposure prophylaxis are a female-initiated HIV prevention method that does not require daily or coitally-dependent dosing. As part of a randomized placebo-controlled trial of a tenofovir disoproxil fumarate intravaginal ring, we assessed product acceptability through in-depth interviews with 18 women during and after 14 days of continuous use. Women reported that the ring was comfortable with few side effects, regardless of experimental arm. However, interest in future use by this cohort was modest for several reasons including: low self-perceived HIV risk; concern that use implied promiscuity; potential for interference with relationship formation and trust; concern for interference with menstruation and cleanliness; and worries about partners' acceptability and sexual pleasure. Potential issues were raised with duration of use prior to ring exchange. Future studies should continue to identify and address individual and relationship factors that influence acceptability, early in the product development process.

Pharmacokinetic bioequivalence, safety and acceptability of Ornibel®, a new polymer composition contraceptive vaginal ring (etonogestrel/ethinylestradiol 11.00/3.474 mg) compared with Nuvaring® (etonogestrel/ethinylestradiol 11.7/2.7 mg)

OBJECTIVE

To show the clinical development of Ornibel^® (ExeltisHealthcare, Spain) a contraceptive vaginal ring manufactured with a new polymer composition and containing etonogestrel/ethinylestradiol, compared to Nuvaring^® (MSD, Spain).

SUBJECTS AND METHODS

Randomised, single dose, 2-period, 2-sequence, 2-stage crossover, comparative bioavailability study conducted in 40 healthy female subjects. All subjects received both treatments for 28 days in each of two periods, separated by a 28 days washout. Ornibel^® contains etonogestrel/ethinylestradiol 11.00/3.47 mg and Nuvaring^® contains etonogestrel/ethinylestradiol 11.7/2.7 mg, both rings delivering 120/15 µg/day. For the calculation of pharmacokinetic parameters, 37 blood samples were collected up to 840 h after each ring insertion to quantify plasma concentrations of etonogestrel and ethinylestradiol using a validated MS/MS-HPLC. Safety was assessed by adverse events recording, clinical laboratory and vital signs and tolerability by vaginal examination. Acceptability was investigated by a 5-point scale questionnaire.

RESULTS

Bioequivalence was demonstrated in the first stage as the 94.12% Confidence Intervals of the primary parameters laid within the 80-125% acceptance range for both etonogestrel (C_max: 96.81-112.20%; AUC_0-504h: 98.71-108.61%; AUC_0-t: 100.14-109.10%) and ethinylestradiol. (C_max: 105.91-120.62%; AUC_0-504h: 105.47-114.59%; AUC_0-t: 108.31-117.61%). During the first day of use a burst effect was observed with Nuvaring^®, with significantly higher level of ethinylestradiol (C_max0-24h ratio: 78.34%, 94.12CI: 73.55-83.45%). Both products were well tolerated and accepted, without significant differences between them.

CONCLUSION

Ornibel^® is bioequivalent to Nuvaring^® in terms of efficacy, safety, tolerability and acceptability. The new polymer composition provides Ornibel^® with more stability and gradual hormonal release during the first day of use, particularly for ethinylestradiol.

End-Users' Product Preference Across Three Multipurpose Prevention Technology Delivery Forms: Baseline Results from Young Women in Kenya and South Africa

A multipurpose prevention technology (MPT) that combines HIV and pregnancy prevention is a promising women’s health intervention, particularly for young women. However, little is known about the drivers of acceptability and product choice for MPTs in this population. This paper explores approval ratings and stated choice across three different MPT delivery forms among potential end-users. The Trio Study was a mixed-methods study in women ages 18–30 that examined acceptability of three MPT delivery forms: oral tablets, injections, and vaginal ring. Approval ratings and stated choice among the products was collected at baseline. Factors influencing stated product choice were explored using multivariable multinomial logistic regression. The majority (62%) of women in Trio stated they would choose injections, 27% would choose tablets and 11% would choose the ring. Significant predictors of choice included past experience with similar contraceptive delivery forms, age, and citing frequency of use as important. Ring choice was higher for older (25–30) women than for younger (18–24) women (aRR = 3.1; p < 0.05). These results highlight the importance of familiarity in MPT product choice of potential for variations in MPT preference by age.

Female condom acceptability in urban India: Examining the role of sexual pleasure

This qualitative study examined the acceptability of female condoms in urban India, with a focus on sexual pleasure. We conducted focus group discussions with 50 women and 19 men, as well as a small number of individual interviews with women ( n = 3), in Chennai and New Delhi. Perceived benefits of female condoms included protection against unintended pregnancy and sexually transmitted infections, increased sense of empowerment for women, and simple clean up. The most common drawback was reduced sensation. Participants suggested structural changes to the female condom to ease insertion and use. Consent and privacy were discussed as increasing sexual pleasure. Pleasure should be acknowledged in design and education efforts to increase female condom use.

Factors associated with nonadherence to instructions for using the Nestorone®/ethinyl estradiol contraceptive vaginal ring

OBJECTIVES

We sought to identify factors associated with nonadherence to instructions for using a novel contraceptive providing 1 year of protection.

STUDY DESIGN

Data from a multicountry Phase 3 trial of the Nestorone® (segesterone acetate)/ethinyl estradiol (NES/EE) contraceptive vaginal ring (CVR) were analyzed. Participants were instructed to use the CVR over 13 cycles and follow a 21/7 regimen. Their reports of CVR removals >2 h outside scheduled removal periods served as a proxy for nonadherence. We used multivariate logistic regression to determine factors associated with such use.

RESULTS

Of 905 participants, 120 (13%) reported CVR removals >2 h. Removals for washing [odds ratio (OR) 3.96, 95% confidence interval (CI) 2.50-6.27] or sexual intercourse (OR 3.19, 95% CI 2.03-4.99), and finding CVR insertion difficult (OR 2.80, 95% CI 1.36-5.80) were factors associated with removals >2 h. Lower educational attainment also predicted ring removal >2 h (OR 3.23, 95% CI 1.55-6.75). Women residing in Europe or Australia were less likely to remove the ring for >2 h compared with women in the United States (OR 0.44, 95% CI 0.24-0.83 and OR 0.13, 95% CI 0.02-0.98, respectively). Participants who reported removals >2 h were more likely to discontinue CVR use (OR 1.93, 95% CI 1.24-2.95), report dissatisfaction (OR 2.20, 95% CI 1.32-3.69) and become pregnant during the study (OR 4.07, 95% CI 1.58-10.50).

CONCLUSIONS

Removing the CVR for washing and removing it before intercourse are factors associated with nonadherence to ring use. These are important topics for counseling women who are considering or using vaginal rings, including the NES/EE CVR.

IMPLICATIONS

Findings from this study may be useful in guiding counseling for current and prospective vaginal ring users. Anticipatory guidance should focus on how the ring feels in the vagina and during sex. Asking about ring removals may help identify women who are at increased risk for having an unplanned pregnancy.

"Per vaginam" topical use of hormonal drugs in women with symptomatic deep endometriosis: a narrative literature review

PURPOSE

We aim to provide a comprehensive overview of the role of the vagina as a route for drug delivery and absorption, with a particular focus on the use of vaginal hormonal compounds for the treatment of deep infiltrating symptomatic endometriosis.

METHODS

A MEDLINE search through PubMed was performed to identify all published studies in English language on vaginal hormonal treatments for symptomatic endometriosis.

RESULTS

Main advantages of the vaginal route include avoidance of the hepatic-first pass metabolic effect, the possibility of using lower therapeutic dosages, and the reduction of side effects compared with the oral administration. Studies on endometriosis treatment mainly focused on the use of vaginal danazol (n = 6) and the contraceptive vaginal ring (n = 2). One pilot study evaluated the efficacy of vaginal anastrozole in women with rectovaginal endometriosis. Most investigations evaluated the vaginal use of hormonal agents in women with deep infiltrating endometriosis/rectovaginal endometriosis. Overall, a substantial amelioration of pelvic pain symptoms associated with endometriosis was observed, particularly of dysmenorrhea. A significant reduction in rectovaginal endometriotic nodule dimensions measured at ultrasound examination was detected by some but not all authors.

CONCLUSIONS

The vaginal route represents a scarcely explored modality for drug administration. High local hormonal concentrations might achieve a greater effect on endometriotic lesions compared with alternative routes. Future studies should focus on the use of the vagina for delivering target therapies particularly in patients with deeply infiltrating rectovaginal lesions.

Thermoplastic polyurethane-based intravaginal rings for prophylaxis and treatment of (recurrent) bacterial vaginosis

The aim of the present study was to develop thermoplastic polyurethane (TPU)-based intravaginal rings (IVRs) for prophylaxis and treatment of bacterial vaginosis via hot melt extrusion/injection molding. Therefore, different TPU grades were processed in combination with lactic acid or metronidazole, targeting a sustained lactic acid release over a 28day-period and sustained metronidazole release over 4-7days. Hot melt extrusion of lactic acid/TPU combinations required a lower extrusion temperature due to the plasticizing properties of lactic acid, evidenced by the lower glass transition temperature (T_g) and cross-over point (T_tanδ=1) values. NIR-chemical imaging data showed a homogenous distribution of lactic acid in TPU matrices at drug loads up to 30% (w/w). The addition of metronidazole did not lower processing temperatures, as the active pharmaceutical ingredient remained crystalline in the TPU matrix. Hydrophobic TPUs with a low ratio between the soft and hard segments (SS/HS ratio) in the polymer structure were suitable carriers for the lactic acid-eluting device over a 28-day period, while hydrophilic TPUs were needed to achieve the required release rate of metronidazole-eluting IVRs. IVRs manufactured with a TPU grade having a higher SS/HS ratio and lactic acid/TPU ratio exhibited a more elastic behavior. The addition of 25% (w/w) metronidazole did not affect the mechanical properties of the IVRs. Hydrophilic TPUs were most prone to biofilm formation by Candida albicans and Staphylococcus aureus, but the incorporation of metronidazole in the device prevented biofilm formation. Based on the drug eluting performance and mechanical tests, a mixture of lactic acid and Tecoflex™ EG-93A (20/80, w/w) and a combination of metronidazole and Tecophilic™ SP-93A-100 (25/75, w/w) were selected to design IVRs for the prophylaxis and treatment of bacterial vaginosis, respectively. Slug mucosal irritation tests predicted low irritation potency for both devices.

Adherence and Acceptability of a Multidrug Vaginal Ring for HIV Prevention in a Phase I Study in the United States

We evaluated the adherence and acceptability of a vaginal ring containing dapivirine, maraviroc, or both drugs for 28 days during a Phase I placebo-controlled trial in 48 HIV-negative sexually abstinent U.S. women aged 18-40. Adherence was assessed weekly by clinical interview and computer-assisted self-interviewing; acceptability assessment occurred at the last product-use visit. Study retention was 98 % (47/48); 94 % (45/48) reported being fully adherent with ring use during the 28-day period. Two participants experienced the ring partially coming out. Analysis was blinded and behavioral data were combined across study groups. Most women reported being very comfortable having the ring in their vagina; 44 % preferred continuous use, whereas 51 % had no preference compared to episodic use. Although a range of minor ring concerns were expressed, few were actually experienced. High adherence to and acceptability of this vaginal ring in this Phase I trial contributes to its promise as a sustained mechanism for multidrug vaginal microbicide delivery.

Microbicide vaginal rings: Technological challenges and clinical development

Vaginal rings (VRs) are flexible, torus-shaped, polymeric devices designed to sustain delivery of pharmaceutical drugs to the vagina for clinical benefit. Following first report in a 1970 patent application, several steroid-releasing VR products have since been marketed for use in hormone replacement therapy and contraception. Since 2002, there has been growing interest in the use of VR technology for delivery of drugs that can reduce the risk of sexual acquisition of human immunodeficiency virus type 1 (HIV-1), the causative agent of acquired immunodeficiency syndrome (AIDS). Although no vaginally-administered product has yet been approved for HIV reduction/prevention, extensive research efforts are continuing and a number of VR devices offering sustained release of so-called 'HIV microbicide' compounds are currently being evaluated in late-stage clinical studies. This review article provides an overview of the published scientific literature within this important field of research, focusing primarily on articles published within peer-reviewed journal publications. Many important aspects of microbicide-releasing VR technology are discussed, with a particular emphasis on the technological, manufacturing and clinical challenges that have emerged in recent years.

Efficacy and safety of the contraceptive vaginal ring (NuvaRing) compared with a combined oral contraceptive in Chinese women: a 1-year randomised trial

OBJECTIVES

The aim of the study was to assess the efficacy and tolerability of the monthly vaginal ring (NuvaRing; 15 μg ethinylestradiol [EE] and 120 μg etonogestrel per day) compared with a monophasic (21/7) combined oral contraceptive (COC) containing 30 μg EE and 3 mg drospirenone in healthy Chinese women aged 18-40 years.

METHODS

This was a phase III, open-label, randomised multicentre trial conducted in China. Participants received NuvaRing or COC for 13 cycles (3 weeks of ring/pill treatment followed by a 1-week ring-free/pill-free period). Contraceptive efficacy was assessed by in-treatment pregnancies and expressed by the Pearl Index (PI; number of pregnancies/100 woman-years of use). Cycle control was assessed by unscheduled (breakthrough) and absence of scheduled (withdrawal) bleeding events. Safety and tolerability were assessed throughout the study.

RESULTS

Participants were randomised either to the NuvaRing (n = 732) or to the COC (n = 214); 588 (82.4%) and 182 (78.4%) participants, respectively, completed the study. There were 10 in-treatment pregnancies in the NuvaRing group (PI 1.92; 95% confidence interval [CI] 0.92, 3.53) and five in the COC group (PI 3.12; 95% CI 1.01, 7.29). Breakthrough bleeding/spotting ranged from 18.6% (Cycle 1) to 4.2% (Cycle 11) for NuvaRing and from 21.6% (Cycle 1) to 7.9% (Cycle 11) for COC. Absence of withdrawal bleeding ranged from 8.6% (Cycle 1) to 3.0% (Cycle 11) for NuvaRing and from 14.6% (Cycle 1) to 6.4% (Cycle 5) for COC. For NuvaRing and COC, respectively, 26.6% and 25.0% of participants had treatment-related adverse events, and 7.0% and 9.1% discontinued the study as a result.

CONCLUSIONS

Once-monthly NuvaRing is efficacious and safe for use in Chinese women.

The Promise of Intravaginal Rings for Prevention: User Perceptions of Biomechanical Properties and Implications for Prevention Product Development

Intravaginal rings (IVRs) are currently under investigation as devices for the delivery of agents to protect against the sexual transmission of HIV and STIs, as well as pregnancy. To assist product developers in creating highly acceptable rings, we sought to identify characteristics that intravaginal ring users consider when making decisions about ring use or non-use. We conducted four semi-structured focus groups with 21 women (aged 18-45) who reported using an IVR in the past 12 months. Participants manipulated four prototype rings in their hands, discussed ring materials, dimensionality, and "behavior," and shared perceptions and appraisals. Five salient ring characteristics were identified: 1) appearance of the rings' surfaces, 2) tactile sensations of the cylinder material, 3) materials properties, 4) diameter of the cylinder, and 5) ring circumference. Pliability (or flexibility) was generally considered the most important mechanical property. Several ring properties (e.g., porousness, dimensionality) were associated with perceptions of efficacy. Women also revealed user behaviors that may impact the effectiveness of certain drugs, such as removing, rinsing and re-inserting the ring while bathing, and removing the ring during sexual encounters. As product developers explore IVRs as prevention delivery systems, it is critical to balance product materials and dimensions with use parameters to optimize drug delivery and the user experience. It is also critical to consider how user behaviors (e.g., removing the ring) might impact drug delivery.

Recent advances on anti-HIV vaginal delivery systems development

A review of the recent outcomes regarding technologies to prevent vaginal transmission of HIV, mainly by using antiretroviral (ARV) drugs formulated as microbicides. An introduction about the HIV transmission mechanisms by the vaginal route is included, together with the recent challenges faced for development of successful microbicide products. The outcomes of clinical evaluations are mentioned, and the different formulation strategies studied to-date, with the requirements, advantages, disadvantages and limitations of each dosage-form type, are presented. Finally, the recent attempts to apply various types of nanotechnologies in order to develop advanced microbicide-products and overcome existing limitations, are discussed.

Acceptability and preferences for vaginal dosage forms intended for prevention of HIV or HIV and pregnancy

This paper reviews key issues found to affect acceptability and preferences for vaginal products to prevent HIV infection or HIV and pregnancy. We focus on the interplay between the biological and physico-chemical aspects of formulation and the social and behavioral issues that may affect use. The need for an HIV prevention product that women can use is driven by women's increased biological and social vulnerability to HIV infection, and thus social and behavioral research on microbicide acceptability has been conducted alongside, as well as separate from, the earliest product development efforts. Some acceptability and preference issues are specific to a product's dosage form, use-requirements, and/or use indications, while others pertain to any vaginal product used for prevention of HIV or pregnancy. Although most of the work cited here was published since 2010, it draws on a much longer trajectory of research.

An Intravaginal Ring for the Simultaneous Delivery of an HIV-1 Maturation Inhibitor and Reverse-Transcriptase Inhibitor for Prophylaxis of HIV Transmission

Nucleocapsid 7 (NCp7) inhibitors have been investigated extensively for their role in impeding the function of HIV-1 replication machinery and their ability to directly inactivate the virus. A class of NCp7 zinc finger inhibitors, S-acyl-2-mercaptobenzamide thioesters (SAMTs), was investigated for topical drug delivery. SAMTs are inherently unstable because of their hydrolytically labile thioester bond, thus requiring formulation approaches that can lend stability. We describe the delivery of N-[2-(3,4,5-trimethoxybenzoylthio)benzoyl]-β-alaninamide (SAMT-10), as a single agent antiretroviral (ARV) therapeutic and in combination with the HIV-1 reverse-transcriptase inhibitor pyrimidinedione IQP-0528, from a hydrophobic polyether urethane (PEU) intravaginal ring (IVR) for a month. The physicochemical stability of the ARV-loaded IVRs was confirmed after 3 months at 40°C/75% relative humidity. In vitro, 25 ± 3 mg/IVR of SAMT-10 and 86 ± 13 mg/IVR of IQP-0528 were released. No degradation of the hydrolytically labile SAMT-10 was observed within the matrix. The combination of ARVs had synergistic antiviral activity when tested in in vitro cell-based assays. Toxicological evaluations performed on an organotypic EpiVaginal(™) tissue model demonstrated a lack of formulation toxicity. Overall, SAMT-10 and IQP-0528 were formulated in a stable PEU IVR for sustained release. Our findings support the need for further preclinical evaluation. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:3426-3439, 2015.

A temperature-monitoring vaginal ring for measuring adherence

BACKGROUND

Product adherence is a pivotal issue in the development of effective vaginal microbicides to reduce sexual transmission of HIV. To date, the six Phase III studies of vaginal gel products have relied primarily on self-reporting of adherence. Accurate and reliable methods for monitoring user adherence to microbicide-releasing vaginal rings have yet to be established.

METHODS

A silicone elastomer vaginal ring prototype containing an embedded, miniature temperature logger has been developed and tested in vitro and in cynomolgus macaques for its potential to continuously monitor environmental temperature and accurately determine episodes of ring insertion and removal.

RESULTS

In vitro studies demonstrated that DST nano-T temperature loggers encapsulated in medical grade silicone elastomer were able to accurately and continuously measure environmental temperature. The devices responded quickly to temperature changes despite being embedded in different thickness of silicone elastomer. Prototype vaginal rings measured higher temperatures compared with a subcutaneously implanted device, showed high sensitivity to diurnal fluctuations in vaginal temperature, and accurately detected periods of ring removal when tested in macaques.

CONCLUSIONS

Vaginal rings containing embedded temperature loggers may be useful in the assessment of product adherence in late-stage clinical trials.

Pharmacokinetics of UC781-loaded intravaginal ring segments in rabbits: a comparison of polymer matrices

UC781 is a potent and poorly water-soluble nonnucleoside reverse transcriptase inhibitor being investigated as a potential microbicide for preventing sexual transmission of HIV-1. This study was designed to evaluate the in vivo release and pharmacokinetics of UC781 delivered from matrix-type intravaginal ring segments in rabbits. Three polymer matrices (polyurethane, ethylene vinyl acetate copolymer, and silicone elastomer) and two drug loadings (5 and 15 mg/segment) were evaluated in at least one of two independent studies for up to 28 days in vivo. Inter-study comparison of in vivo release, vaginal tissue, and plasma concentrations for similar formulations demonstrated good reproducibility of the animal model. Mean estimates for a 28-day in vivo release ranged from 0.35 to 3.17 mg UC781 per segment. Mean proximal vaginal tissue levels (adjacent to the IVR segment) were 8-410 ng/g and did not change significantly with time for most formulations. Distal vaginal tissue levels of UC781 were 6- to 49-fold lower than proximal tissue levels. Mean UC781 plasma levels were low for all formulations, at 0.09-0.58 ng/mL. All formulations resulted in similar UC781 concentrations in vaginal tissue and plasma, except the low loading polyurethane group which provided significantly lower levels. Loading dependent release and pharmacokinetics were only clearly observed for the polyurethane matrix. Based on these results, intravaginal ring segments loaded with UC781 led to vaginal tissue concentrations ranging from below to approximately two orders of magnitude higher than UC781's EC50 under in vitro conditions (2.8 ng/mL), with little influence by polymer matrix or UC781 loading. Moreover, these findings support the use of rabbit vaginal pharmacokinetic studies in preclinical testing of microbicide intravaginal rings.

Engineering a degradable polyurethane intravaginal ring for sustained delivery of dapivirine

We describe the engineering of a degradable intravaginal ring (IVR) for the delivery of the potent HIV-1 reverse transcriptase inhibitor dapivirine. The degradable polymer used in fabricating the device incorporated poly(caprolactone) ester blocks in a poly(tetramethylene ether) glycol ABA type polyurethane backbone. The polymer was designed to maintain its structure for 1 month during usage and then degrade in the environment post-disposal. In vitro release of dapivirine showed zero-order kinetics for up to 1 month and significant levels of drug release into engineered vaginal tissue. The mechanical properties of the degradable IVR were comparable to those of a widely used contraceptive intravaginal ring upon exposure to simulated vaginal conditions. Incubation under simulated vaginal conditions for a month caused minimal degradation with minimal effect on the mechanical properties of the ring and polymer. The cytotoxicity evaluation of the drug-loaded IVRs against Vk2/E6E7 human vaginal epithelial cells, Lactobacillus jensenii, and engineered vaginal tissue constructs showed the degradable polyurethane to be non-toxic. In vitro evaluation of inflammatory potential monitored through the levels of inflammatory cytokines IL-8, IL-1α, IL-6, IL-1β, and MIP-3α when engineered EpiVaginal™ tissue was incubated with the polyurethanes suggested that the degradable polyurethane was comparable to commercial medical grade polyurethane. These results are encouraging for further development of this degradable IVR for topical vaginal delivery of microbicides.

Exploring vaginal ring acceptability for contraception and sexually transmissible infection protection in India: a qualitative research study

Background New vaginal rings are being developed as single and multipurpose prevention technologies to protect women from pregnancy and/or sexually transmissible infections, such as HIV. Data on ring acceptability in low-resource settings is critical for new technologies to meet user needs.

METHODS

Women from slum and lower-income areas around Delhi, India, participated in focus group discussions on vaginal ring product perceptions and preferences. Participants were recruited based on following eligibility categories: age, marital status, contraceptive use, and number of children. The translated transcriptions of the qualitative data were analysed using a coding scheme generated from the areas of inquiry and relevant literature.

RESULTS

A total of 103 women from lower-middle-class or slum areas in Delhi participated in 13 focus group discussions between December 2012 and January 2013. Participants shared perceptions of vaginal ring product attributes, including size, colour, intended use (single indication or dual purpose), duration of use, side effects, biodegradability, and various preferences regarding product use, including access, use during sex, wear patterns, cleaning, and disposal. Participants also reflected on willingness to pay and male partner acceptability.

CONCLUSIONS

The results of this hypothetical acceptability study indicate that these low-income women in Delhi are: willing to try vaginal rings; unconcerned about wearing them during sex; very interested in protection from infections and unintended pregnancy; indifferent about colour of new rings; emphatic about being told that rings may change colour from menstrual blood staining; comfortable with thinner rings; willing to try thicker rings once familiar with thinner rings; in favour of starting with 1-month rings and then transitioning to longer-term rings; and in favour of first accessing rings at a facility and then managing resupply independently.