Current status of contraceptive vaginal rings

Acceptability of the Nestorone®/ethinyl estradiol contraceptive vaginal ring: development of a model; implications for introduction

OBJECTIVES

Develop and test a theoretical acceptability model for the Nestorone®/ethinyl estradiol contraceptive vaginal ring (CVR); explore whether domains of use within the model predict satisfaction, method adherence and CVR continuation.

STUDY DESIGN

Four domains of use were considered relative to outcome markers of acceptability, that is, method satisfaction, adherence and continuation. A questionnaire to evaluate subjects' experiences relative to the domains, their satisfaction (Likert scale) and adherence to instructions for use was developed and administered to 1036 women enrolled in a 13-cycle Phase 3 trial. Method continuation was documented from the trial database. Stepwise logistic regression (LR) analysis was conducted and odds ratios (ORs) calculated to assess associations of satisfaction with questions from the four domains. Fisher's Exact Test was used to determine the association of satisfaction with outcome measures.

RESULTS

A final acceptability model was developed based on the following determinants of CVR satisfaction: ease of use, side effects, expulsions/feeling the CVR and sexual activity including physical effects during intercourse. Satisfaction was high (89%) and related to higher method adherence [OR, 2.6 (1.3, 5.2)] and continuation [OR, 5.5 (3.5, 8.4)]. According to the LR analysis, attributes of CVR use representing items from the four domains - finding it easy to remove, not complaining of side effects, not feeling the CVR while wearing it and experiencing no change or an increase in sexual pleasure and/or frequency - were associated with higher odds of satisfaction.

CONCLUSION

Hypothesized domains of CVR use were related to satisfaction, which was associated with adherence and continuation. Results provide a scientific basis for introduction and future research.

IMPLICATIONS STATEMENT

Acceptability research is important when introducing a new method of contraception and determining whether it can be a successful option in meeting the reproductive health needs of women and men. This study was designed to test a conceptual model of acceptability and identify factors associated with successful use of a new contraceptive delivery modality. Original research was conducted for this publication.

Quality of sexual life of women using the contraceptive vaginal ring in extended cycles: preliminary report

OBJECTIVE

To evaluate the quality of the sexual life of healthy women who are using a contraceptive vaginal ring (CVR) in extended cycles.

METHODS

Fifty-two women (18 to 32 years old) seeking hormonal contraception were enrolled in this prospective study. Women were to use a CVR releasing daily 15 μg of ethinylestradiol (EE) and 120 μg of etonogestrel (ENG) for 63 days, followed by a four-day hormone-free interval, for two such extended cycles. At baseline and at the first (day 63-73) and second (day 126-134) follow-ups the Female Sexual Function Index (FSFI) and the Short Form-36 (SF-36) questionnaires were administered to investigate, respectively, sexual behaviour and the quality of life (QoL). The Female Sexual Distress Scale (FSDS) was used to verify whether sexual dysfunction caused significant personal distress to the woman.

RESULTS

The FSFI and FSDS scores obtained at the first and second follow-up appointments detected an improvement with respect to the baseline score (p < 0.05). QoL measures of body pain, general health and emotional role improved at the first follow-up visit (p < 0.05); at the second one, all variables showed improvement (p < 0.05).

CONCLUSION

According to these preliminary data the CVR in extended cycles could improve the sexual function and the QoL of women.

New and emerging contraceptives: a state-of-the-art review

Background

The first hormonal contraceptive was introduced onto the market in several countries 50 years ago; however, the portfolio of contraceptive methods remains restricted with regards to their steroid composition, their cost, and their ability to satisfy the requirements of millions of women/couples in accordance with their different reproductive intentions, behaviors, cultures, and settings.

Methods

A literature review was conducted using Medline, Embase, and Current Contents databases, up to September 1, 2013 to identify publications reporting new contraceptives in development using combinations of the search terms: contraception, contraceptives, oral contraceptives, patch, vaginal ring, implants, intrauterine contraceptives, and emergency contraception (EC). Also, several experts in the field were also consulted to document ongoing projects on contraception development. Additionally, the Clinicaltrial.gov website was searched for ongoing studies on existing contraceptive methods and new and emerging female contraceptives developed over the past 5 years. Information was also obtained from the pharmaceutical industry.

Results

Early sexual debut and late menopause means that women may require contraception for up to 30 years. Although oral, injectable, vaginal, transdermal, subdermal, and intrauterine contraceptives are already available, new contraceptives have been developed in an attempt to reduce side effects and avoid early discontinuation, and to fulfill women’s different requirements. Research efforts are focused on replacing ethinyl-estradiol with natural estradiol to reduce thrombotic events. In addition, new, less androgenic progestins are being introduced and selective progesterone receptor modulators and new delivery systems are being used. In addition, research is being conducted into methods that offer dual protection (contraception and protection against human immunodeficiency virus transmission), and contraceptives for use “on demand.” Studies are also investigating non-hormonal contraceptive methods that have additional, non-contraceptive benefits.

Conclusion

The most pressing need worldwide is, first, that the highly effective contraceptive methods already available should be affordable to most of the population and also that these methods should fulfill the needs of women of different ages and with different reproductive requirements. The development of new contraceptive methods should also take advantage of the knowledge obtained over the past 30 years on gamete physiology and gamete interaction to avoid the use of steroid compounds.

Multipurpose prevention technologies: products in development

Multipurpose prevention technologies (MPTs) are broadly defined as products capable of simultaneously addressing multiple sexual and reproductive health needs including unintended pregnancy, STIs including HIV-1, and other reproductive tract infections. MPTs have been discussed for a few decades but little product development has occurred. With the recent proof-of-concept that a topically applied antiretroviral (ARV) can effectively reduce sexual transmission of HIV-1 (tenofovir 1% gel) the impetus to develop MPTs is gaining momentum. Products currently in development are broadly categorized as either long-acting or on-demand. Long-acting MPTs include intravaginal rings (IVRs) and long-acting injectable products. Several IVR MPTs are under development including one designed to release tenofovir to prevent transmission of HIV-1 and levonorgestrel (LNG) to prevent unintended pregnancy over a 90-day period. Another MPT IVR under development is designed to release the ARV dapivirine and LNG for 2 months. Long-acting injectable pre-exposure prophylaxis (PrEP) formulations of rilpivirine (TMC278) and GSK1265744 have entered clinical evaluation and could form the basis of long-acting injectable products for HIV-1 prevention and prevention of unintended pregnancy. On-demand products include TFV 1% gel (HIV-1/HSV-2 prevention), a zinc/carrageenan zinc gel (HIV-1/HSV-2 prevention), and the SILCS diaphragm administered with TFV 1% gel. Significant technical, funding, and regulatory hurdles must be overcome to develop most MPTs; however, the significant reproductive health benefits to many women around the world should provide motivation to overcome these hurdles. This article is based on a presentation at the "Product Development Workshop 2013: HIV and Multipurpose Prevention Technologies", held in Arlington, Virginia on February 21-22, 2013. It forms part of a special supplement to Antiviral Research.

Intravaginal rings as delivery systems for microbicides and multipurpose prevention technologies

There is a renewed interest in delivering pharmaceutical products via intravaginal rings (IVRs). IVRs are flexible torus-shaped drug delivery systems that can be easily inserted and removed by the woman and that provide both sustained and controlled drug release, lasting for several weeks to several months. In terms of women's health care products, it has been established that IVRs effectively deliver contraceptive steroids and steroids for the treatment of postmenopausal vaginal atrophy. A novel application for IVRs is the delivery of antiretroviral drugs for the prevention of human immunodeficiency virus (HIV) genital infection. Microbicides are antiviral drugs delivered topically for HIV prevention. Recent reviews of microbicide IVRs have focused on technologies in development and optimizing ring design. IVRs have several advantages, including the ability to deliver sustained drug doses for long periods of time while bypassing first pass metabolism in the gut. IVRs are discreet, woman-controlled, and do not require a trained provider for placement or fitting. Previous data support that women and their male sexual partners find IVRs highly acceptable. Multipurpose prevention technology (MPT) products provide protection against unintended/mistimed pregnancy and reproductive tract infections, including HIV. Several MPT IVRs are currently in development. Early clinical testing of new microbicide and MPT IVRs will require a focus on safety, pharmacokinetics and pharmacodynamics. Specifically, IVRs will have to deliver tissue concentrations of drugs that are pharmacodynamically active, do not cause mucosal alterations or inflammation, and do not change the resident microbiota. The emergence of resistance to antiretrovirals will need to be investigated. IVRs should not disrupt intercourse or have high rates of expulsion. Herein, we reviewed the microbicide and MPT IVRs currently in development, with a focus on the clinical aspects of IVR assessment and the challenges facing microbicide and MPT IVR product development, clinical testing, and implementation. The information in this review was drawn from PubMed searches and a recent microbicide/MPT product development workshop organized by CONRAD.

Skin patch and vaginal ring versus combined oral contraceptives for contraception

BACKGROUND

The delivery of combination contraceptive steroids from a transdermal contraceptive patch or a contraceptive vaginal ring offers potential advantages over the traditional oral route. The transdermal patch and vaginal ring could require a lower dose due to increased bioavailability and improved user compliance.

OBJECTIVES

To compare the contraceptive effectiveness, cycle control, compliance (adherence), and safety of the contraceptive patch or the vaginal ring versus combination oral contraceptives (COCs).

SEARCH METHODS

Through February 2013, we searched MEDLINE, POPLINE, CENTRAL, LILACS, ClinicalTrials.gov, and ICTRP for trials of the contraceptive patch or the vaginal ring. Earlier searches also included EMBASE. For the initial review, we contacted known researchers and manufacturers to identify other trials.

SELECTION CRITERIA

We considered randomized controlled trials comparing a transdermal contraceptive patch or a contraceptive vaginal ring with a COC.

DATA COLLECTION AND ANALYSIS

Data were abstracted by two authors and entered into RevMan. For dichotomous variables, the Peto odds ratio (OR) with 95% confidence intervals (CI) was calculated. For continuous variables, the mean difference was computed. We also assessed the quality of evidence for this review.

MAIN RESULTS

We found 18 trials that met our inclusion criteria. Of six patch studies, five examined the marketed patch containing norelgestromin plus ethinyl estradiol (EE); one studied a patch in development that contains levonorgestrel (LNG) plus EE. Of 12 vaginal ring trials, 11 examined the same marketing ring containing etonogestrel plus EE; one studied a ring being developed that contains nesterone plus EE.Contraceptive effectiveness was not significantly different for the patch or ring versus the comparison COC. Compliance data were limited. Patch users showed better compliance than COC users in three trials. For the norelgestromin plus EE patch, ORs were 2.05 (95% CI 1.83 to 2.29) and 2.76 (95% CI 2.35 to 3.24). In the levonorgestrel plus EE patch report, patch users were less likely to have missed days of therapy (OR 0.36; 95% CI 0.25 to 0.51). Of four vaginal ring trials, one found ring users had more noncompliance (OR 3.99; 95% CI 1.87 to 8.52), while another showed more compliance with the regimen (OR 1.67; 95% CI 1.04 to 2.68).More patch users discontinued early than COC users. ORs from two meta-analyses were 1.59 (95% CI 1.26 to 2.00) and 1.56 (95% CI 1.18 to 2.06) and another trial showed OR 2.57 (95% CI 0.99 to 6.64). Patch users also had more discontinuation due to adverse events than COC users. Users of the norelgestromin-containing patch reported more breast discomfort, dysmenorrhea, nausea, and vomiting. In the levonorgestrel-containing patch trial, patch users reported less vomiting, headaches, and fatigue.Of 11 ring trials with discontinuation data, two showed the ring group discontinued less than the COC group: OR 0.32 (95% CI 0.16 to 0.66) and OR 0.52 (95% CI 0.31 to 0.88). Ring users were less likely to discontinue due to adverse events in one study (OR 0.32; 95% CI 0.15 to 0.70). Compared to the COC users, ring users had more vaginitis and leukorrhea but less vaginal dryness. Ring users also reported less nausea, acne, irritability, depression, and emotional lability than COC users.For cycle control, only one trial study showed a significant difference. Women in the patch group were less likely to have breakthrough bleeding and spotting. Seven ring studies had bleeding data; four trials showed the ring group generally had better cycle control than the COC group.

AUTHORS' CONCLUSIONS

Effectiveness was not significantly different for the methods compared. Pregnancy data were available from half of the patch trials but two-thirds of ring trials. The patch could lead to more discontinuation than the COC. The patch group had better compliance than the COC group. Compliance data came from half of the patch studies and one-third of the ring trials. Patch users had more side effects than the COC group. Ring users generally had fewer adverse events than COC users but more vaginal irritation and discharge.The quality of the evidence for this review was considered low for the patch and moderate for the ring. The main reasons for downgrading were lack of information on the randomization sequence generation or allocation concealment, the outcome assessment methods, high losses to follow up, and exclusions after randomization.