Accurate measurement of female genital tract fluid dilution in cervicovaginal lavage samples

In vitro and ex vivo models for evaluating vaginal drug delivery systems

Vaginal drug delivery systems are often preferred for treating a variety of diseases and conditions of the female reproductive tract (FRT), as delivery can be more targeted with less systemic side effects. However, there are many anatomical and biological barriers to effective treatment via the vaginal route. Further, biocompatibility with the local tissue and microbial microenvironment is desired. A variety of in vitro and ex vivo models are described herein for evaluating the physicochemical properties and toxicity profile of vaginal drug delivery systems. Deciding whether to utilize organoids in vitro or fresh human cervicovaginal mucus ex vivo requires careful consideration of the intended use and the formulation characteristics. Optimally, in vitro and ex vivo experimentation will inform or predict in vivo performance, and examples are given that describe utilization of a range of methods from in vitro to in vivo. Lastly, we highlight more advanced model systems for other mucosa as inspiration for the future in model development for the FRT.

Fractional CO2 laser treatment effect on cervicovaginal lavage zinc and copper levels: a prospective cohort study

BACKGROUND

The basic principle of vaginal laser therapy is the rejuvenation of the affected tissue. Zinc and copper are essential nutritional trace elements and have a key role in connective tissue homeostasis. We aimed to investigate the effect of vaginal, fractional CO₂ laser treatment on cervicovaginal lavage (CVL) zinc and copper levels.

METHODS

Twenty-nine postmenopausal women with symptoms of vaginal dryness were enrolled in our prospective cohort study. Three treatments with MonaLisa Touch CO₂ laser system were performed four weeks apart. At each treatment CVL was collected, Vaginal Health Index (VHI) was obtained, and Visual Analog Scale (VAS) for vaginal dryness was assigned by patients. Zinc and copper concentrations were measured with optical emission spectrometry before each treatment and six weeks after the 3rd treatment.

RESULTS

The VHI scores significantly improved after each laser treatment (mean ± SD VHI score, 13.03 ± 4.49 before vs. 15.55 ± 4.35 after the 1st, 17.79 ± 4.57 after the 2nd and 19.38 ± 4.39 after the 3rd treatment, P < 0.01). Similarly, VAS scores reflected improvement (mean ± SD VAS score 6.59 ± 2.86 before vs. 4.17 ± 2.86 after the 1st, 2.45 ± 2.43 after the 2nd and 1.41 ± 1.94 after the 3rd treatment, P < 0.01). CVL zinc levels were significantly higher compared to copper levels (0.06 ± 0.04 vs. 0.006 ± 0.006 mg/L, P < 0.01) at baseline. While copper levels remained the same through treatments, the CVL zinc level was significantly higher after the second laser treatment compared to the baseline.

CONCLUSIONS

Fractional CO₂ laser treatment of the vagina impacts CVL zinc and copper levels differently. While CVL copper levels were not different after each laser treatment, zinc levels were significantly higher after the second treatment before returning to baseline values.

Characterization of smallholder pig production systems in the Western Cape, South Africa

This study set out to characterize the farming and management practices of smallholder pig production systems in the Western Cape, South Africa. Data was gathered in three municipalities: Khayelitsha (27 farmers), Mamre (26 farmers) and Malmesbury (22 farmers) with the use of a structured questionnaire through both face-to-face and telephonic interviews. The study revealed that smallholder pig farmers in the Western Cape owned on average 37.4 ± 50.5 pigs. Majority of farmers (61%) made use of tattoo markings to identify their pigs, 6% made use of ear tags and 4% clipped the ears of their pigs. More than 25% of farmers did not use any method of identification to mark their pigs. More than half of the respondents (51%) do not have formal recordkeeping systems in place. Livestock theft was found to be a major problem amongst farmers. No differences were found amongst the three study areas and the type of housing system used (P > 0.05). The most popular materials pens were constructed of across the three areas were wood (40%), corrugated iron (16%) or a combination of the two (32%); other materials used were cement blocks (5%), polystyrene (1%) or plastic (1%). Pig farmers kept 43% Large White, 43 % crossbred and 14% Landrace across the three districts. Commercial feed was used by 61% of Mamre farmers whereas Khayelitsha farmers fed an equal amount of by-products (44%) and mixed (44%) feed to their pigs, whereas Malmesbury fed 44% mixed, 33% commercial and 24% by-products obtained from factories to their pigs. Piglet mortality due to the sow lying on her piglets was experienced by 47% of farmers interviewed, whilst 29% had experienced piglet mortalities due to the cold. Perturbingly, 76% of farmers did not send dead pigs for a post-mortem, stating that they could not rely on veterinarians or afford their services. Smallholder pig farmers in Malmesbury (68%) and Khayelitsha (70%) sold their pigs to the informal market, indicating that keeping pigs provided a source of revenue. Mamre marketed 88% of their pigs as weaners, Khayelitsha marketed 73% of their pigs as growers, whereas Malmesbury kept 32% of their pigs as breeding stock. Khayelitsha and Malmesbury marketed their growers at 63.3 ± 41.2 kg and 51.5 ± 30.2 kg, respectively, to the informal market. The study highlights the farming practices of smallholder pig farmers in three districts in the Western Cape. There a few differences in the practices of these farmers, but overall, there are similar limitations that hinder them from improved production, such as limited recordkeeping, theft, lack of infrastructure and finances for post-mortem examination. Smallholder pig farmers in the Western Cape are still mainly selling to the informal market. This informal market is not fully characterized yet in the Western Cape, and more studies are needed to further determine and investigate the benefits of only selling to the informal market.

Cervicovaginal lavage fluid zinc level as a marker of vaginal atrophy

OBJECTIVES

This study aimed to investigate the correlation between cervicovaginal fluid zinc levels and participants' menopausal status and the presence of vulvovaginal symptoms of genitourinary syndrome of menopause.

METHODS

Women included in the study underwent a pelvic examination, collection of vaginal cytology, and cervicovaginal lavage was performed in a standardized fashion. The cervicovaginal lavage zinc content was determined. The vaginal health index was calculated, and the visual analog scale was obtained based on the participant's burning, itching, vaginal pain, dyspareunia, dryness, and dysuria.

RESULTS

One hundred twenty women participated in the study. Eighty-two participants were menopausal. The mean vaginal health index was 15 ± 6, while the total visual analog scale score was 14 ± 14. We found significant differences between cervicovaginal lavage zinc level and age group, menopausal status, presence of vaginal dryness, and vaginal atrophy. We also found a moderate positive correlation between Vaginal Maturation Value and cervicovaginal lavage zinc levels (r = 0.495, P value < 0.01) in the correlation analysis. However, in the multivariate regression model, including all significant factors, only vaginal atrophy remained significant.

CONCLUSIONS

We found a significant association between vaginal atrophy (vaginal maturation value < 50) and cervicovaginal lavage zinc levels. Zinc levels of cervicovaginal lavage could be used as a new marker of vaginal atrophy. : Video Summary:http://links.lww.com/MENO/A575.

Surrogate post-coital testing for contraceptive efficacy against human sperm activity in the ovine vaginal model†

High unintended pregnancy rates are partially due to lack of effective nonhormonal contraceptives; development of safe, effective topical vaginal methods will address this need. Preclinical product safety and efficacy assessment requires in vivo testing in appropriate models. The sheep is a good model for the evaluation of vaginally delivered products due to its close similarities to humans. The study objective was to develop an ovine model for efficacy testing of female nonhormonal contraceptives that target human sperm. Fresh human semen was pooled from male volunteers. Nonpregnant female Merino sheep were treated with control or vaginal contraceptive product (IgG antibody with action against sperm or nonoxynol-9 [N9]). Pooled semen was added to the sheep vagina and mixed with product and vaginal secretions. Microscopic assessment of samples was performed immediately and progressive motility (PM) of sperm was compared between treatments. Cytokines CXCL8 and IL1B were assessed in vaginal fluid after instillation of human semen. No adverse reactions or elevations in proinflammatory cytokines occurred in response to human semen. N9 produced signs of acute cellular toxicity while there were no cellular changes after IgG treatment. N9 and IgG had dose-related effects with the highest dose achieving complete sperm immobilization (no sperm with PM). Surrogate post-coital testing of vaginally administered contraceptives that target human semen was developed in an ovine model established for vaginal product preclinical testing. This expanded model can aid the development of much needed nonhormonal topical vaginal contraceptives, providing opportunities for rapid iterative drug development prior to costly, time-intensive human testing.

Safety and pharmacokinetics of single, dual, and triple antiretroviral drug formulations delivered by pod-intravaginal rings designed for HIV-1 prevention: A Phase I trial

BACKGROUND

Intravaginal rings (IVRs) for HIV pre-exposure prophylaxis (PrEP) theoretically overcome some adherence concerns associated with frequent dosing that can occur with oral or vaginal film/gel regimens. An innovative pod-IVR, composed of an elastomer scaffold that can hold up to 10 polymer-coated drug cores (or "pods"), is distinct from other IVR designs as drug release from each pod can be controlled independently. A pod-IVR has been developed for the delivery of tenofovir (TFV) disoproxil fumarate (TDF) in combination with emtricitabine (FTC), as daily oral TDF-FTC is the only Food and Drug Administration (FDA)-approved regimen for HIV PrEP. A triple combination IVR building on this platform and delivering TDF-FTC along with the antiretroviral (ARV) agent maraviroc (MVC) also is under development.

METHODOLOGY AND FINDINGS

This pilot Phase I trial conducted between June 23, 2015, and July 15, 2016, evaluated the safety, pharmacokinetics (PKs), and acceptability of pod-IVRs delivering 3 different ARV regimens: 1) TDF only, 2) TDF-FTC, and 3) TDF-FTC-MVC over 7 d. The crossover, open-label portion of the trial (N = 6) consisted of 7 d of continuous TDF pod-IVR use, a wash-out phase, and 7 d of continuous TDF-FTC pod-IVR use. After a 3-mo pause to evaluate safety and PK of the TDF and TDF-FTC pod-IVRs, TDF-FTC-MVC pod-IVRs (N = 6) were evaluated over 7 d of continuous use. Safety was assessed by adverse events (AEs), colposcopy, and culture-independent analysis of the vaginal microbiome (VMB). Drug and drug metabolite concentrations in plasma, cervicovaginal fluids (CVFs), cervicovaginal lavages (CVLs), and vaginal tissue (VT) biopsies were determined via liquid chromatographic-tandem mass spectrometry (LC-MS/MS). Perceptibility and acceptability were assessed by surveys and interviews. Median participant age was as follows: TDF/TDF-FTC group, 26 y (range 24-35 y), 2 White, 2 Hispanic, and 2 African American; TDF-FTC-MVC group, 24.5 y (range 21-41 y), 3 White, 1 Hispanic, and 2 African American. Reported acceptability was high for all 3 products, and pod-IVR use was confirmed by residual drug levels in used IVRs. There were no serious adverse events (SAEs) during the study. There were 26 AEs reported during TDF/TDF-FTC IVR use (itching, discharge, discomfort), with no differences between TDF alone or in combination with FTC observed. In the TDF-FTC-MVC IVR group, there were 12 AEs (itching, discharge, discomfort) during IVR use regardless of attribution to study product. No epithelial disruption/thinning was seen by colposcopy, and no systematic VMB shifts were observed. Median (IQR) tenofovir diphosphate (TFV-DP) tissue concentrations of 303 (277-938) fmol/10(6) cells (TDF), 289 (110-603) fmol/10(6) cells (TDF-FTC), and 302 (177.1-823.8) fmol/10(6) cells (TDF-FTC-MVC) were sustained for 7 d, exceeding theoretical target concentrations for vaginal HIV prevention. The study's main limitations include the small sample size, short duration (7 d versus 28 d), and the lack of FTC triphosphate measurements in VT biopsies.

CONCLUSIONS

An innovative pod-IVR delivery device with 3 different formulations delivering different regimens of ARV drugs vaginally appeared to be safe and acceptable and provided drug concentrations in CVFs and tissues exceeding concentrations achieved by highly protective oral dosing, suggesting that efficacy for vaginal HIV PrEP is achievable. These results show that an alternate, more adherence-independent, longer-acting prevention device based on the only FDA-approved PrEP combination regimen can be advanced to safety and efficacy testing.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02431273.

Evaluation of the Pig-Tailed Macaque (Macaca nemestrina) as a Model of Human Staphylococcus aureus Nasal Carriage

Staphylococcus aureus nasal carriage is a common condition affecting both healthy and immunocompromised populations and provides a reservoir for dissemination of potentially infectious strains by casual contact. The factors regulating the onset and duration of nasal S. aureus colonization are mostly unknown, and a human-relevant animal model is needed. Here, we screened 17 pig-tailed macaques (Macaca nemestrina) for S. aureus carriage, and 14 of 17 animals tested positive in the nose at one or both screening sessions (8 weeks apart), while the other 3 animals were negative in the nose but positive in the pharynx at least once. As in humans, S. aureus colonization was densest in the nose, and treatment of the nostrils with mupirocin ointment effectively cleared the nostrils and 6 extranasal body sites. Experimental nasal S. aureus colonization was established with 10⁴ CFU/nostril, and both autologous and nonautologous strains survived over 40 days without any apparent adverse effects. A human nasal S. aureus isolate (strain D579, sequence type 398) was carried in 4 of 6 animals for over 3 weeks. Nostrils that did eradicate experimentally applied S. aureus exhibited neutrophilic innate immunity marked by elevated nasal interleukin-1β (IL-1β), IL-8, and monocyte chemotactic protein 1 levels and a 10-fold decreased IL-1 receptor antagonist/IL-1β ratio within 7 days postinoculation, analogous to the human condition. Taken together, pig-tailed macaques represent a physiological model of human S. aureus nasal carriage that may be utilized for testing natural colonization and decolonization mechanisms as well as novel classes of anti-S. aureus therapeutics.

Combination Pod-Intravaginal Ring Delivers Antiretroviral Agents for HIV Prophylaxis: Pharmacokinetic Evaluation in an Ovine Model

Preexposure prophylaxis (PrEP) against HIV using oral regimens based on the nucleoside reverse transcriptase inhibitor tenofovir disoproxil fumarate (TDF) has been effective to various degrees in multiple clinical trials, and the CCR5 receptor antagonist maraviroc (MVC) holds potential for complementary efficacy. The effectiveness of HIV PrEP is highly dependent on adherence. Incorporation of the TDF-MVC combination into intravaginal rings (IVRs) for sustained mucosal delivery could increase product adherence and efficacy compared with oral and vaginal gel formulations. A novel pod-IVR technology capable of delivering multiple drugs is described. The pharmacokinetics and preliminary local safety characteristics of a novel pod-IVR delivering a combination of TDF and MVC were evaluated in the ovine model. The device exhibited sustained release at controlled rates over the 28-day study and maintained steady-state drug levels in cervicovaginal fluids (CVFs). Dilution of CVFs during lavage sample collection was measured by ion chromatography using an inert tracer, allowing corrected drug concentrations to be measured for the first time. Median, steady-state drug levels in vaginal tissue homogenate were as follows: for tenofovir (TFV; in vivo hydrolysis product of TDF), 7.3 × 10(2) ng g(-1) (interquartile range [IQR], 3.0 × 10(2), 4.0 × 10(3)); for TFV diphosphate (TFV-DP; active metabolite of TFV), 1.8 × 10(4) fmol g(-1) (IQR, 1.5 × 10(4), 4.8 × 10(4)); and for MVC, 8.2 × 10(2) ng g(-1) (IQR, 4.7 × 10(2), 2.0 × 10(3)). No adverse events were observed. These findings, together with previous pod-IVR studies, have allowed several lead candidates to advance into clinical evaluation.