The efficacy and acceptability of a low-dose levonorgestrel intravaginal ring for contraception in a UK cohort

Preference, adherence, and acceptability of 3 nonmedicated intravaginal rings of differing external diameters: a randomized, crossover trial

BACKGROUND

No empirical data support the 54 to 58 mm external diameter of intravaginal rings currently available and in development for contraception and other indications. Understanding how external diameter affects preference, adherence, and acceptability is critical for optimizing future product development.

OBJECTIVE

Our primary objectives were to determine which of 3 nonmedicated rings of differing external diameters was preferred and yielded the highest adherence. Secondary objectives were comparing acceptability, patterns of adherence, and safety of the 3 rings.

STUDY DESIGN

In an open-label, 3-way crossover trial, healthy, HIV-uninfected, monogamous, sexually active, nonpregnant, 18-year-old to 40-year-old cisgender women and their male partners in Atlanta, GA and the Bronx, NY were randomly assigned to the sequence of using 3 nonmedicated silicone rings (46 mm, 56 mm, and 66 mm external diameters) continuously for approximately 30 days each (90 days total; November 2021 to December 2022). We tested whether end-of-study preference for any of the 3 rings was greater than 0.33 (binomial proportion, exact test). We used mixed-effect regression models with random intercepts by participants to compare adherence (ring never out for more than 30 minutes in 24 hours) and probability of removals (including reasons for removal), expulsions, and the ring being out of the vagina all day, per ring, per day of use with the 56-mm ring as the reference group and to compare scores on a novel 19-item acceptability scale with items related to ease and experience of use and impact on sex.

RESULTS

Of 24 women, 23 completed the study (median age: 26.7 years [standard deviation: 3.78]). Most were college graduates (92%), White (63%), non-Hispanic (79%), single (79%), and nulliparous (92%). At the end of the study, 59% preferred the smallest (46 mm) ring versus 18% each for the 56-mm and 66-mm rings (P=.0045). The proportion of participants who were adherent did not differ by ring (46 mm, 78%; 56 mm, 75%; 66 mm, 59%; P=.30); however, odds of expulsion were higher for the 46-mm (odds ratio: 5.72; 95% confidence interval: 1.25-26.1) and 66-mm (odds ratio: 25.9; 95% confidence interval: 6.11-109) rings than for the 56-mm ring. The 66-mm ring also had greater odds of being out (removal or expulsion, any length of time) than the 56-mm ring (odds ratio: 6.50; 95% confidence interval: 3.46-12.2). Mean acceptability scale scores were identical (4.54/5) for the 46-mm and 56-mm (smallest and medium) rings and significantly higher than for the largest, 66-mm ring (3.94/5; P<.001).

CONCLUSION

Although the 46-mm ring was preferred by more women and had higher rates of adherence compared to the other 2 rings, the 56-mm ring was rated as equally acceptable with significantly fewer reports of expulsions/removals compared to the other 2 rings. These data confirm that the current 54 to 58 mm diameter of vaginal rings on the market and in development is acceptable and performs well. Future studies should explore the effect of other mechanical attributes, such as compressibility, on preference, adherence, and acceptability, as well as investigating ring characteristics in other populations.

Vaginal ring acceptability: A systematic review and meta-analysis of vaginal ring experiences from around the world

OBJECTIVE

The vaginal ring (ring) is a female-initiated, long-acting drug delivery system for different indications, including HIV prevention. Our aim was to provide evidence for acceptability of the vaginal ring across indications to support dapivirine and multipurpose prevention technology ring introduction and roll out.

STUDY DESIGN

This systematic review and meta-analysis followed PRISMA guidelines. We searched PubMed, Web of Science, Embase, and grey literature for publications reporting favorable ring acceptability and secondary outcomes involving actual ring use (comfort, ease of ring use, ring comfort during sex, expulsions, and vaginal symptoms) or hypothetical acceptability for any indication published January 1, 1970-June 15, 2021. We estimated random-effects pooled prevalence, assessing between-study variation using meta-regression.

RESULTS

Of 2,234 records, we included 123 studies with 40,434 actual and hypothetical ring users. The primary outcome assessment included 50 studies with 60 ring subgroups totaling 19,271 ring users. The favorable acceptability pooled prevalence was 85.6% (95%CI 81.3, 89.0), while hypothetical acceptability among non-ring users was 27.6% (95%CI 17.5, 40.5). In meta-regression, acceptability was higher in menopause (95.4%; 95%CI 88.4, 98.2) compared to contraceptive rings (83.7%; 95%CI 75.6, 89.5). Acceptability was lower in pharmacokinetic studies (50%; 95%CI 22.1, 77.9) compared to RCTs (89.5%; 95%CI 85.8.92.4) and in studies assessing acceptability at ≥12 months (78.5%; 95%CI 66.5, 87.1) versus studies assessing acceptability at <3 months (91.9%; 95%CI 83.7, 96.1). European (90.6%; 95%CI 83.9, 94.7), Asian (97.1%; 95%CI 92.0, 99.0), and multi-region studies (93.5%; 95%CI 84.6, 97.4) reported more favorable acceptability compared to African studies (59.4%; 95%CI 38.3, 77.5). Secondary outcomes were similarly favorable, including ring comfort (92.9%; 95%CI 89.2, 95.4), ease of use (90.9%; 95%CI 86.5, 94.0), and comfort during sex (82.7%; 95%CI 76.4, 87.6). Limitations include inconsistent outcome definitions and unmeasured factors affecting acceptability.

CONCLUSIONS

Women who used vaginal rings reported they were acceptable across indications geographic regions and indications. Policy makers should consider the ring as an important option for pregnancy and HIV prevention drug development.

IMPLICATIONS

This review found favorable acceptability among vaginal ring users across indications and geographic areas, in contrast to low hypothetical acceptability among non-users. Vaginal rings are an important drug delivery system for pregnancy and HIV preventions, and scale-up should plan to address initial hesitancy among new users.

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.

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.

Vaginal ring delivery of hormone replacement therapy--a review

Vaginal ring delivery systems are a highly promising approach to hormone replacement therapy (HRT). The vagina is an excellent route for steroid absorption. Menopausal vaginal rings can be designed to allow very low dose local delivery of oestrogen to the vagina for the large percentage of postmenopausal women experiencing urogenital atrophy, or can be modified to deliver much higher doses sufficient for systemic oestrogen replacement therapy, with or without simultaneous progestogen release. Clinical studies of ultra-low dose rings have shown them to be as efficacious as established treatments of urogenital atrophy (creams, pessaries) and to be preferred by most users. Pharmacokinetic and limited clinical studies of vaginal rings designed to deliver systemic doses of HRT (oestrogen alone or combined) have also been highly promising. Vaginal ring delivery of HRT offers women convenient, long-acting therapy (>/= 3 months) that is under their own personal control.

Patient acceptability of and tolerance to a placebo intravaginal ring in hysterectomized women: a pilot study

OBJECTIVE

To assess the tolerance to and patient acceptability of a placebo intravaginal ring in hysterectomized, postmenopausal women over a 28-day period.

DESIGN

Open, single-center.

SETTING

University hospital specialist menopause clinic.

PARTICIPANTS

A total of 24 healthy postmenopausal women attending menopause clinics at King's College Hospital and the Amarant Centre, London.

MAIN OUTCOME MEASURES

Discomfort, ring expulsions, bowel, urinary and sexual difficulties associated with the ring and women's overall views on this method.

RESULTS

The major problems with use of the intravaginal ring were patient discomfort, involuntary ring expulsion and sexual partner discomfort. These were experienced by 13, 11 and seven women and their partners, respectively, and resulted in premature discontinuation by three women who suffered discomfort and two women who experienced recurrent involuntary ring expulsion.

CONCLUSIONS

Two-thirds of the patients found the intravaginal ring acceptable, one-third did not.

The effect of small doses of progesterone released from two types of vaginal rings on ovarian activity and bleeding patterns during the first postpartum year

A total of 20 breastfeeding women used progesterone-releasing vaginal rings for up to 12 months. The women were divided into two groups, one (n = 9) using rings with an initial release rate of 5 mg/24 h, the other (n = 11) with a release rate of 20 mg/24 h. Individual women started to give breast milk supplements and ceased to breastfeed after various periods of time. Urinary estrone and pregnanediol glucuronide levels were measured by radioimmunoassay three times weekly during the entire trial. Individual diary cards were used to register bleeding and spotting. A significantly higher concentration of pregnanediol glucuronide was seen when the 20 mg/24 h ring was used in the lactation period, in comparison with the 5 mg/24 h ring. In the post-lactation period, pregnanediol glucuronide levels dropped when the 20 mg/24 h ring was used. Estrone glucuronide levels increased after the termination of breastfeeding, indicating an enhanced suppression of ovarian activity in the lactation period with both rings. Although the degree of suppression was dose-related, both rings were likely to offer a sufficient contraceptive effect in the lactation period. No significant changes were observed when milk supplements were added to breastfeeding. The use of the 20 mg/24 h ring resulted in a much better bleeding pattern (significantly less bleeding days) than the 5 mg/24 h ring during the lactation period. In the post-lactation period, the 20 mg/24 h ring the bleeding because much worse than in the lactation period.(ABSTRACT TRUNCATED AT 250 WORDS)

Studies on a vaginal ring releasing levonorgestrel at an initial rate of 27 micrograms/24 h when used alone or in combination with transdermal systems releasing estradiol

Vaginal rings releasing levonorgestrel (L-NOG) at an initial rate of 27 micrograms/24h were studied in a group of 24 normally menstruating women during three months (i.e., during three four-week segments). Each segment consisted of three weeks with the vaginal rings in situ followed by a treatment-free period of one week. The women were divided into three groups (8 subjects each). The first group received vaginal rings only, the second and third groups were treated, in addition, with transdermal systems (patches) releasing estradiol at a rate of 50 and 100 micrograms/24h, respectively. Peripheral blood samples were withdrawn three times weekly (Monday, Wednesday and Friday) during a pretreatment cycle and during the following three months of treatment. The levels of L-NOG, estradiol and progesterone were analyzed by radioimmunoassay techniques. In all subjects, endometrial biopsies were taken in a control cycle and during the last days with vaginal rings in situ in segments II and III. The treatment with estradiol did not significantly influence L-NOG levels. Considerable differences in the L-NOG levels between the subjects of the same group were observed. Fluctuation in ovarian reaction within groups was also large. Nevertheless, estradiol noticeably increased the proportion of anovulatory cycles; the total number of anovulatory segments was 5, 9 and 19 (out of 24) in the groups "No estradiol", "50 micrograms/24h estradiol" and "100 micrograms/24h estradiol", respectively. A morphometric study of the endometrium indicated a significant decrease in the diameter of glands. This change was due to L-NOG alone, but it seemed to be accentuated by the exogenous estradiol. The occurrence of glandular mitoses increased in both groups receiving estradiol in a dose-dependent manner, indicating an increased endometrial proliferation. The treatment with estradiol did not significantly alter the bleeding pattern.

Pharmacokinetic and pharmacodynamic effects of vaginal rings releasing levonorgestrel at a rate of 27 micrograms/24 hours: a pilot study

The pharmacokinetic and pharmacodynamic effects of vaginal rings releasing levonorgestrel (L-NOG) at an initial rate of 27 micrograms/24 h were studied in a group of 12 normally menstruating women during 90 days of continuous use (i.e., during three 30-day treatment segments). Blood samples were drawn immediately before insertion, 15 and 30 min, as well as 1, 2, 4, 8, 12 and 24 h after insertion of the rings, and thereafter three times weekly throughout the study for the analysis of L-NOG, estradiol, progesterone and sex hormone-binding globulin (SHBG). Endometrial biopsies were obtained for a morphometric analysis in a pre-treatment (control) cycle and in the 6th and 10th weeks of treatment. The peak of average L-NOG levels was reached within two hours after the insertion of rings. Until 24 h after insertion, the levels did not change significantly. Thereafter, a decrease at a rate of 0.2% per day was initiated. The L-NOG and SHBG levels were highly correlated. This was seen for both the pre-treatment SHBG vs L-NOG (r = 0.96) and the treatment SHBG vs L-NOG levels (r = 0.92). There was a significant (p < 0.001) decrease of SHBG levels due to treatment. During the total of 36 treatment segments, a normal ovarian function was seen in 47% of the segments. The women were anovulatory and had an inadequate lutal function in 28% and 25% of segments, respectively. No correlation between the L-NOG levels and ovarian reaction to treatment was found. The use of L-NOG induced significant changes in the endometrium; the number of glands/mm2 decreased after 6 (p < 0.02) and 10 weeks of use (p < 0.01). Also, the diameter of glands and the occurrence of vacuolated cells decreased significantly (p < 0.02 and p < 0.005, respectively). None of the endometrial parameters or dating was correlated with the ovarian reaction to treatment, indicating independent endometrial effects of L-NOG.