A Longitudinal Assessment of Cervical Inflammation and Immunity Associated with HIV-1 Infection, Hormonal Contraception, and Pregnancy

Vaginal Bacteria and Proinflammatory Host Immune Mediators as Biomarkers of Human Immunodeficiency Virus Acquisition Risk Among African Women

BACKGROUND

Few investigations have assessed contributions of both vaginal bacteria and proinflammatory immune mediators to human immunodeficiency virus (HIV) acquisition risk in a prospective cohort.

METHODS

We conducted a nested case-control study of African women who participated in a randomized placebo-controlled trial of daily oral versus vaginal tenofovir-based preexposure prophylaxis for HIV infection. Vaginal concentrations of 23 bacterial taxa and 16 immune mediators were measured. Relationships between individual bacterial concentrations or immune mediators and HIV risk were analyzed using generalized estimating equations in a multivariable model. Factor analysis assessed relationships between combinations of bacterial taxa, immune mediators, and HIV acquisition risk.

RESULTS

We identified 177 HIV pre-seroconversion visits from 150 women who acquired HIV and 531 visits from 436 women who remained HIV uninfected. Fourteen bacterial taxa and 6 proinflammatory cytokines and chemokines were individually associated with greater HIV risk after adjusting for confounders. Women with all 14 taxa versus <14 taxa (adjusted odds ratio [aOR], 4.45 [95% confidence interval {CI}, 2.20-8.98]; P < .001) or all 6 immune mediators versus <6 mediators (aOR, 1.77 [95% CI, 1.24-2.52]; P < .001) had greater risk for HIV acquisition. Factor analysis demonstrated that a bacterial factor comprised of 14 high-risk bacterial taxa (aOR, 1.57 [95% CI, 1.27-1.93]; P < 0.001) and the interferon gamma-induced protein 10 (highest quartile: aOR, 3.19 [95% CI, 1.32-7.72]; P = 0.002) contributed to the highest HIV risk.

CONCLUSIONS

Bacterial and host biomarkers for predicting HIV acquisition risk identify women at greatest risk for HIV infection and can focus prevention efforts.

Update on the Impact of Depot Medroxyprogesterone Acetate on Vaginal Mucosal Endpoints and Relevance to Sexually Transmitted Infections

PURPOSE OF REVIEW

The long-acting reversible intramuscularly-injected contraceptive depot medroxyprogesterone acetate (DMPA-IM) is widely used by cisgender women in Africa. Although DMPA-IM provides reliable contraception, potential effects on the female genital tract (FGT) mucosa have raised concern, including risk of HIV infection. This review summarises and compares evidence from observational cohort studies and the randomised Evidence for Contraceptive Options in HIV Outcomes (ECHO) Trial.

RECENT FINDINGS

Although previous observational studies found women using DMPA-IM had higher abundance of bacterial vaginosis (BV)-associated bacteria, increased inflammation, increased cervicovaginal HIV target cell density, and epithelial barrier damage, sub-studies of the ECHO Trial found no adverse changes in vaginal microbiome, inflammation, proteome, transcriptome, and risk of viral and bacterial STIs, other than an increase in Th17-like cells. Randomised data suggest that DMPA-IM use does not adversely change mucosal endpoints associated with acquisition of infections. These findings support the safe use of DMPA-IM in women at high risk of acquiring STIs, including HIV.

Associations of circulation levels of cytokines with birthweight, preterm birth, spontaneous miscarriages, and stillbirth: A Mendelian randomization analysis

Background: The association between immune imbalances and adverse pregnancy outcomes has been extensive investigated by observational studies, but remain unclear. Thus, this study aimed to establish the causality of the circulation levels of cytokines on adverse pregnancy outcomes, such as offspring's birthweight (BW), preterm birth (PTB), spontaneous miscarriage (SM), and stillbirth (SB). Methods: Two-sample Mendelian randomization (MR) analysis was employed to investigate potential causal relations between 41 cytokines and pregnancy outcomes on the basis of previously published GWAS datasets. Multivariable MR (MVMR) analysis was implemented to investigate the effect of the composition of cytokine networks on the pregnancy outcomes. Potential risk factors were further estimated to explore the potential mediators. Results: Genetic correlation analysis based on large GWAS data sources revealed that genetically predicted MIP1b (β = -0.027, S.E. = 0.010, p = 0.009) and MCSF (β = -0.024, S.E. = 0.011, p = 0.029) were associated with reduced offspring's BW, MCP1 (OR: 0.90, 95% CI: 0.83-0.97, p = 0.007) was associated with reduced SM risk, SCF (β = -0.014, S.E. = 0.005, p = 0.012) associated with decreased number of SB in MVMR. The univariable MR showed that GROa (OR: 0.92, 95% CI: 0.87-0.97, p = 0.004) was associated with decreased PTB risk. Except for the MCSF-BW association, all above associations surpassed the Bonferroni corrected threshold. The MVMR results revealed that MIF, SDF1a, MIP1b, MCSF and IP10 composed cytokine networks, associated with offspring's BW. Risk factors analysis indicated that the above causal associations might be mediated by smoking behaviors. Conclusion: These findings suggest the causal associations of several cytokines with adverse pregnancy outcomes, which were potentially mediated by smoking and obesity. Some of the results did not been corrected through multiple tests and larger samples verification is required in further studies.

Considerations for Choosing Soluble Immune Markers to Determine Safety of Novel Vaginal Products

Several soluble cytokines have been associated with microbicide-induced cervicovaginal inflammation, non-optimal vaginal microbiota, and risk of HIV acquisition. Many of these biomarkers are used in preclinical assays to estimate the safety of vaginally applied products. However, there are currently no validated biomarkers to evaluate the safety of novel vaginal products in clinical trials. This hinders the rapid and rational selection of novel products being tested in first-in-human trials. We reviewed available literature to assess how best to select and measure soluble immune markers to determine product safety in first in human clinical trials of novel vaginal products.

The Effect Of Contraception On Genital Cytokines In Women Randomized To Copper Intrauterine Device, Intramuscular Depot Medroxyprogesterone Acetate Or Levonorgestrel Implant

BACKGROUND

The ECHO Trial randomized women to intramuscular depot medroxyprogesterone acetate (DMPA-IM), levonorgestrel implant (LNG-implant), or copper intrauterine device (Cu-IUD). In a sub-study of the ECHO Trial, we tested the hypothesis that contraceptives influence genital inflammation by comparing cervicovaginal cytokine changes following contraception initiation. In addition, we compared cytokine profiles in women who acquired HIV (cases) versus those remaining HIV-negative (controls).

METHODS

Women (n=251) from South Africa and Kenya were included. Twenty-seven cervicovaginal cytokines were measured by Luminex at baseline, 1- and 6-month post-contraceptive initiation. In addition, cytokines were measured pre-seroconversion in HIV cases (n=25) and controls (n=100).

RESULTS

At 6-months post-contraceptive initiation, women using Cu-IUD had increased concentrations of 25/27 cytokines compared to their respective baseline concentrations. In contrast, women initiating DMPA-IM and LNG-implant did not experience changes in cervicovaginal cytokines. Pre-seroconversion concentrations of IL-1β, IL-6, and TNF-α, previously associated with HIV risk, correlated with increased HIV risk in a logistic regression analysis, although not significantly after correcting for multiple comparisons. Adjusting for contraceptive arm did not alter these results.

CONCLUSION

Although Cu-IUD use broadly increased cervicovaginal cytokine concentrations at 6-months post-insertion, these inflammatory changes were found not to be a significant driver of HIV risk.

Antigen Presenting Cells Link the Female Genital Tract Microbiome to Mucosal Inflammation, With Hormonal Contraception as an Additional Modulator of Inflammatory Signatures

The microbiome of the female genital tract (FGT) is closely linked to reproductive health outcomes. Diverse, anaerobe-dominated communities with low Lactobacillus abundance are associated with a number of adverse reproductive outcomes, such as preterm birth, cervical dysplasia, and sexually transmitted infections (STIs), including HIV. Vaginal dysbiosis is associated with local mucosal inflammation, which likely serves as a biological mediator of poor reproductive outcomes. Yet the precise mechanisms of this FGT inflammation remain unclear. Studies in humans have been complicated by confounding demographic, behavioral, and clinical variables. Specifically, hormonal contraception is associated both with changes in the vaginal microbiome and with mucosal inflammation. In this study, we examined the transcriptional landscape of cervical cell populations in a cohort of South African women with differing vaginal microbial community types. We also investigate effects of reproductive hormones on the transcriptional profiles of cervical cells, focusing on the contraceptive depot medroxyprogesterone acetate (DMPA), the most common form of contraception in sub-Saharan Africa. We found that antigen presenting cells (APCs) are key mediators of microbiome associated FGT inflammation. We also found that DMPA is associated with significant transcriptional changes across multiple cell lineages, with some shared and some distinct pathways compared to the inflammatory signature seen with dysbiosis. These results highlight the importance of an integrated, systems-level approach to understanding host-microbe interactions, with an appreciation for important variables, such as reproductive hormones, in the complex system of the FGT mucosa.

An updated review on the effects of depot medroxyprogesterone acetate on the mucosal biology of the female genital tract

Background

Access to safe, effective, and affordable contraception is important for women’s health and essential to mitigate maternal and fetal mortality rates. The progestin‐based contraceptive depot medroxyprogesterone acetate (DMPA) is a popular contraceptive choice with a low failure rate and convenient administration schedule.

Aim

In this review, we compiled observational data from human cohorts that examine how DMPA influences the mucosal biology of the female genital tract (FGT) that are essential in maintaining vaginal health, including resident immune cells, pro‐inflammatory cytokines, epithelial barrier function, and the vaginal microbiome

Materials and Methods

This review focused on the recent published literature published in 2019 and 2020.

Results

Recent longitudinal studies show that DMPA use associates with an immunosuppressive phenotype, increase in CD4+CCR5+ T cells, and alterations to growth factors. In agreement with previous meta‐analyses, DMPA use is associated with minimal effects of the composition of the vaginal microbiome. Cross‐sectional studies associate a more pro‐inflammatory relationship with DMPA, but these studies are confounded by inherent weaknesses of cross‐sectional studies, including differences in study group sizes, behaviors, and other variables that may affect genital inflammation.

Discussion & Conclusion

These recent results indicate that the interactions between DMPA and the vaginal mucosa are complex emphasizing the need for comprehensive longitudinal studies that take into consideration the measurement of multiple biological parameters.

Comparative Analysis of Vaginal Microbiota in Women with Breast Cancer in Kazakhstan

OBJECT

The relevance of the article is that the breast cancer is a leading oncological disease in women in developed countries and has the highest mortality caused by malignant neoplasms in women. The purpose of the study is to evaluate vaginal microbiota in women with various breast cancer subtypes and compared groups.

METHODS

The study involved 278 women with breast cancer, of whom 174 were patients receiving combination therapy; the control group consisted of 104 patients who had had breast cancer 2-4 years ago.

RESULTS

It was found that despite a significant decrease in the total number of Lactobacillus spp., there were no statistically significant changes in the numbers of microorganisms in patients with different subtypes of breast cancer. According to the results of the comparative analysis, the representatives of obligate anaerobic flora Peptostreptococcus spp. prevailed in vaginal microbiota in luminal A and luminal B subtypes, and the representative of the facultative anaerobic organisms Staphylococcus spp. - in unfavourable outcomes in Her2/Neu+ and triple-negative subtypes.

CONCLUSION

The observed features of the vaginal microbiota in women with different subtypes of breast cancer require further studies for preventive purposes.
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Differential Elevation of Inflammation and CD4+ T Cell Activation in Kenyan Female Sex Workers and Non-Sex Workers Using Depot-Medroxyprogesterone Acetate

Background

Depot Medroxyprogesterone (DMPA) is one of the most widely used contraceptives in Sub-Saharan Africa where HIV incidence is high. We explored the effect of DMPA on the activation of HIV cellular targets and inflammation as a possible mechanism of increased HIV risk with DMPA use. Since sex work is known to affect the immune system, this study aimed to understand the effect of DMPA on the immune system among sex workers and non-sex worker women.

Methods

Twenty-seven DMPA-using HIV seronegative female sex workers (FSW) and 30 DMPA-using HIV seronegative non-sex worker (SW) women were enrolled in the study. Twenty-four FSWs and 30 non-sex workers who were not using any hormonal contraception (no HC) were recruited as controls. Blood and cervico-vaginal samples were collected from all participants and assayed for T cell activation and proinflammatory cytokines.

Results

Among no HC users, sex workers had lower expression of CD38 and CD69 on blood-derived CD4⁺ T cells along with lower CD4⁺CCR5⁺ cells frequency in the endocervix. Plasma MCP-1, TNFα and IL-17 also had reduced expression in FSW not using HC. Non-sex workers using DMPA had elevated proportions of blood-derived CD4⁺CD38⁺, CD4⁺CD69⁺ and CD4⁺HLA-DR⁺ T cells relative to non-sex workers who were not taking any HC. DMPA-using non-sex workers also had an increased level of plasma interferon gamma (IFN-γ), monokine induced by interferon-γ (MIG) and sCD40L, alongside higher proportion of CD4⁺CD38⁺ and CD4⁺CD69⁺ T cells at the cervix compared to non-sex workers no-HC controls., Finally, non-sex workers and FSWs using DMPA had similar levels of genital and peripheral CD4⁺ T cell activation and inflammation.

Conclusion

DMPA increased inflammation and expression of activation markers on potential HIV target cells in non-sex workers. These data show that DMPA is a strong immune modulator and its use counteracts the decreased immune activation associated with sex work. These findings suggest that inflammation and increased HIV target cells in blood and at the genital tract may be mechanisms by which DMPA increases susceptibility to HIV.

Vaginal microbiome-hormonal contraceptive interactions associate with the mucosal proteome and HIV acquisition

Alterations to the mucosal environment of the female genital tract, such as genital inflammation, have been associated with increased HIV acquisition in women. As the microbiome and hormonal contraceptives can affect vaginal mucosal immunity, we hypothesized these components may interact in the context of HIV susceptibility. Using previously published microbiome data from 685 women in the CAPRISA-004 trial, we compared relative risk of HIV acquisition in this cohort who were using injectable depot medroxyprogesterone acetate (DMPA), norethisterone enanthate (NET-EN), and combined oral contraceptives (COC). In women who were Lactobacillus-dominant, HIV acquisition was 3-fold higher in women using DMPA relative to women using NET-EN or COC (OR: 3.27; 95% CI: 1.24–11.24, P = 0.0305). This was not observed in non-Lactobacillus-dominant women (OR: 0.95, 95% CI: 0.44–2.15, P = 0.895) (interaction P = 0.0686). Higher serum MPA levels associated with increased molecular pathways of inflammation in the vaginal mucosal fluid of Lactobacillus-dominant women, but no differences were seen in non-Lactobacillus dominant women. This study provides data suggesting an interaction between the microbiome, hormonal contraceptives, and HIV susceptibility.

Alterations to the mucosal environment of the female genital tract have been associated with increased HIV acquisition in women. As both the vaginal microbiome and hormonal contraceptives affect mucosal immunity, we investigated their interaction with HIV susceptibility. We characterized the vaginal microbiomes in 685 women from the CAPRISA-004 trial, who utilized three major types of hormonal contraceptives including injectable depot medroxyprogesterone acetate (DMPA), norethisterone enanthate (NET-EN), and combined oral contraceptives (COC). In the 40% of women with Lactobacillus-depleted microbiomes, HIV acquisition was not different between contraceptive groups. However, in the 60% of women with Lactobacillus as the dominant bacterial taxa, HIV acquisition risk was 3-fold higher (in women using DMPA relative to women using NET-EN and COC). Higher serum medroxyprogesterone acetate levels in Lactobacillus dominant women associated with increased cervicovaginal inflammation pathways in the mucosal proteome, biomarkers of which associated with HIV susceptibility. This study provides data suggesting an interaction between the microbiome, hormonal contraceptives, and HIV susceptibility.

Concomitant Imbalances of Systemic and Mucosal Immunity Increase HIV Acquisition Risk

BACKGROUND

We previously reported association of increased cervical RANTES and decreased secretory leukocyte protease inhibitor (SLPI) with higher risk of HIV acquisition in reproductive-age women. We now examine the interaction of concomitantly altered systemic and cervical immunity on such risk.

METHODS

We measured immune biomarkers in 4390 cervical and 2390 paired serum specimens at quarterly visits in 218 HIV seroconverters and 784 seronegative women. We assessed proinflammatory (IL-1β, IL-6, IL-8, MIP-3α, and RANTES), anti-inflammatory (IL-1RA and SLPI), vascular activation (vascular endothelial growth factor and Intercellular Adhesion Molecule-1) and defensin (BD2) cervical biomarkers and systemic (peripheral blood) C reactive protein (CRP), IL-6, IL-7, and sCD14 as indicators of immune dysregulation. Biomarker levels were Box-Cox transformed and odds ratios for HIV acquisition calculated based on top quartile or higher/lower than median levels for all HIV-negative visits.

RESULTS

Subsequent HIV acquisition was associated with 5 of 14 individual biomarkers: low systemic CRP [odds ratio (OR) = 1.49, 1.21-1.83] and IL-6 (OR = 1.23, 1.00-1.51), high cervical BD-2 (OR = 1.33, 1.11-1.58) and RANTES (OR = 1.20, 1.01-1.43), and low cervical IL-1RA (OR = 0.65, 0.48-0.86). Low systemic CRP concomitant with altered cervical immunity, especially high BD2, conveyed highest HIV risk (1.63, 1.29-2.05). Additional markers of increased risk emerged when low systemic CRP coincided with: low systemic IL-6 and IL-7 (OR = 1.53, 1.18-1.97); high cervical IL-8 and MIP-3α (OR = 1.40, 1.07-1.83); high cervical IL-1β and IL-6 (OR = 1.43, 1.09-1.86); or low cervical SLPI (OR = 1.36, 1.08-1.71).

CONCLUSIONS

Changes in both peripheral and mucosal immunity may precede and predispose women to HIV infection. Suppressed systemic immunity (ie, low CRP) alone or in combination with imbalanced cervical innate immunity (high proinflammatory and low anti-inflammatory mediators) indicated increased vulnerability to infection. Understanding these combined effects on HIV susceptibility is essential to preventing new infections.

Is the Injectable Contraceptive Depo-Medroxyprogesterone Acetate (DMPA-IM) Associated with an Increased Risk for HIV Acquisition? The Jury Is Still Out

Intramuscular depo-medroxyprogesterone acetate (DMPA-IM) is the most widely used hormonal contraceptive in sub-Saharan Africa. Previous meta-analyses of observational studies found a significant 40%–50% increased risk associated with DMPA-IM use, relative to no contraception or infrequent condom use. This raised substantial concerns, although these studies had important limitations. Consequently, the open-label randomized Evidence for Contraceptive Options and HIV Outcomes trial was conducted, designed primarily to detect a 50% or greater difference in HIV risk between DMPA-IM, the levonorgestrel (LNG) implant, and the copper-intrauterine device. The ECHO study, published in July 2019, concluded that there is no substantial difference in HIV risk among the methods evaluated, and that all three methods are safe and highly effective. In response, the WHO relaxed the Medical Eligibility Criteria for DMPA-IM use among women at high HIV risk in August 2019. However, two of the three comparisons in the ECHO trial could rule out neither a 50% increase nor no change in HIV risk for one contraceptive compared with another. The study had limitations and the results contained considerable uncertainty. They also did not inform on associated HIV risk for any one of the individual methods due to the absence of a control group such as no contraception or only infrequent condom use. The HIV risks associated with LNG implant and copper-IUD relative to no contraception or infrequent condom use are unknown and these cannot be seen as controls, nor did the authors claim them to be. The results will be discussed in the context of their limitations, what they add to the body of work to date on contraception and HIV acquisition, and the implications of the findings and reports thereof for future research and contraceptive choice.

Aberrant cervical innate immunity predicts onset of dysbiosis and sexually transmitted infections in women of reproductive age

Sexually transmitted infections (STIs) and vaginal dysbiosis (disturbed resident microbiota presenting with abnormal Nugent score or candidiasis) have been associated with mucosal inflammation and risk of HIV-1 infection, cancer and poor reproductive outcomes. To date, the temporal relationships between aberrant cervical innate immunity and the clinical onset of microbial disturbance have not been studied in a large population of reproductive age women. We examined data from a longitudinal cohort of 934 Ugandan and Zimbabwean women contributing 3,274 HIV-negative visits who had complete laboratory, clinical and demographic data. Among those, 207 women later acquired HIV, and 584 women were intermittently diagnosed with C. trachomatis (CT), N. gonorrhoeae (NG), genital herpes (HSV-2), T. vaginalis (TV), candidiasis, and abnormal intermediate (4–6) or high (7–10) Nugent score, i.e. bacterial vaginosis (BV). Immune biomarker concentrations in cervical swabs were analyzed by generalized linear and mixed effect models adjusting for site, age, hormonal contraceptive use (HC), pregnancy, breastfeeding, genital practices, unprotected sex and overlapping infections. High likelihood ratios (1.5–4.9) denoted the values of cervical immune biomarkers to predict onset of abnormal Nugent score and candidiasis at the next visits. When controlling for covariates, higher levels of β-defensin-2 were antecedent to BV, CT and HSV-2, lower anti-inflammatory ratio IL-1RA:IL-1β–to intermediate Nugent scores and candida, lower levels of the serine protease inhibitor SLPI–to candida, lower levels of the adhesion molecule ICAM-1 –to TV, and lower levels of the oxidative stress mitigator and endothelial activation marker VEGF–to NG. Changes in innate immunity following onset of dysbiosis and infections were dependent on HC use when controlling for all other covariates. In conclusion, imminent female genital tract dysbiosis or infection can be predicted by distinct patterns of innate immunity. Future research should characterize biotic and abiotic determinants of this pre-existing innate immunity state.

The Effect of Hormonal Contraception on Cervicovaginal Mucosal End Points Associated with HIV Acquisition

Reproductive age women may choose to concurrently use topical antiretrovirals and hormonal contraceptives (HCs) to simultaneously prevent HIV-1 infection and unintended/mistimed pregnancy. There are conflicting data on the effect of HCs on mucosal susceptibility to HIV-1. The objective of this study was to evaluate cervicovaginal (CV) mucosal data from healthy women before and after initiation of either oral contraceptive pills (OCPs) or depot medroxyprogesterone acetate (DMPA) injection. CONRAD A10-114 was a prospective, open-label, parallel cohort study. We enrolled 74 women and 62 completed the visits (32 and 30 who selected OCPs and DMPA, respectively). Participants provided CV lavage, vaginal biopsies, and CV swabs at baseline in the luteal phase and then ∼6 weeks after initiating HCs. After contraceptive initiation, there were significant increases in vaginal immune cell density among both DMPA and OCP users. Changes for OCP users were concentrated in the subepithelial lamina propria, whereas for DMPA users, they were distributed throughout the vaginal tissue, including the epithelium (CD45⁺, CD3⁺, CD4⁺, and CD1a⁺). Contraceptive use altered concentrations of soluble CV inflammatory and immune mediators, with significant reductions in some proinflammatory cytokines and secretory leukoprotease inhibitor. Compared with baseline, p24 antigen production after ex vivo HIV-1 infection of vaginal biopsies doubled after DMPA use, but all p-values were >.05. HIV-1 replication was significantly higher in DMPA-exposed tissues compared with those from the OCP group at the end of the tissue culture (p = .01). Although not statistically significant, median in vitro inhibition of HIV-1 by CV fluid (innate antiviral activity), was reduced by ∼50% with HCs (p > .21). Exposure to exogenous contraceptive hormones significantly increased vaginal immune cells and reduced CV proinflammatory cytokines and antimicrobial peptides. DMPA users showed higher susceptibility to HIV-1 ex vivo infection.

A phase I randomized safety study of a single-size silicone rubber diaphragm used with or without a lactic-acid-containing diaphragm gel

OBJECTIVES

To evaluate a lactic-acid-containing diaphragm gel (Contragel®) approved outside the United States for use with a silicone rubber diaphragm (Caya®). The study gel is being evaluated as a safer alternative to nonoxynol-9 (N-9) gel, which has been associated with risk of increasing susceptibility to human immunodeficiency virus (HIV).

STUDY DESIGN

This was a Phase I randomized, parallel study evaluating the safety of the novel diaphragm gel versus hydroxyethylcellulose (HEC) universal placebo gel delivered by the study diaphragm for two 7-day test cycles of daily use, without and with intercourse. The primary clinical safety endpoint was treatment emergent adverse events. Mucosal safety endpoints included colposcopic findings, anti-Escherichia coli activity of endocervical and vaginal fluid, immune mediators, Nugent score and ectocervical immune cell density. Endpoints were assessed prior to each test cycle and at day 7 of each test cycle. We compared the two independent groups and also evaluated paired changes from baseline in each gel cohort.

RESULTS

Twenty-three participants used the study diaphragm with the novel gel (n=11) or with HEC (n=12). Use of either gel resulted in few genital AEs and no colposcopic findings. There were no differences in ectocervical histology and lymphocyte density or phenotype between the two cohorts at baseline or after each test cycle. We found no clinically important differences in the anti-microbial (anti Escherichia coli) activity of endocervical or vaginal fluid or concentrations of genital immune mediators (e.g. anti-inflammatory secretory leukocyte protease inhibitor (SLPI) or pro-inflammatory mediator RANTES) between the two gel cohorts at any visit. There were no important paired changes from baseline among participants using either gel in Nugent score, ectocervical histology or anti-microbial activity of genital secretions.

CONCLUSIONS

We found no clinically significant differences in clinical and mucosal safety endpoints between the two cohorts. The mucosal safety profiles of the study gel and HEC placebo gel were similar.

IMPLICATIONS

Our data demonstrate no clinically important differences between the safety profiles of the lactic-acid-containing diaphragm gel versus HEC placebo gel when used with the study diaphragm. N-9 can no longer be used with contraceptive diaphragms in high HIV prevalence regions. Although larger studies are needed, the novel gel appears safe for use with the study diaphragm, which is the first over-the-counter, non-hormonal, diaphragm.