Why consider vaginal drug administration?

Improving the safety of N,N-dimethylacetamide (DMA) as a potential treatment for preterm birth in a pregnant mouse model using a vaginal nanoformulation

Vaginal administration and the uterine first pass effect allow for preferential delivery of drugs to the reproductive tract. Dimethylacetamide has previously been shown to delay preterm birth in a pregnant mouse model when given intraperitoneally but the effectiveness of a vaginal nanoformulation of dimethylacetamide has yet to be tested. The purpose of this study was to compare the two formulations of dimethylacetamide for efficacy in rescuing pups from preterm birth in an inflammation-induced mouse model, effects on the maternal fetal interface, and pharmacokinetic profiles in maternal plasma. Timed pregnant CD1 mice were given a 1.56 mg/kg intraperitoneal dose of lipopolysaccharide followed by 3 doses of either vaginal dimethylacetamide or intraperitoneal dimethylacetamide. Mice were monitored for 48 h and times of deliveries were recorded. Additionally, CD1 mice in late gestation were given a single dose of either vaginal or intraperitoneal dimethylacetamide and blood was drawn at 3 different time points following administration. Vaginal administration of dimethylacetamide had similar efficacy in delaying inflammation induced preterm birth as intraperitoneal administration but resulted in lower concentrations in the systemic circulation and decreased effects on the maternal fetal interface. Vaginal nanoformulations should be explored for their potential therapeutic value for the delay of preterm birth.

Immunotherapy of endometrial cancer via CD47 blockade-mediated macrophage phagocytosis

The interaction between CD47 expressed on cancer cells and signal regulatory protein-α located on macrophages blocks the phagocytosis of tumor cells by macrophages. Our data reveal that human endometrial cancer cells (hECCs) upregulate the CD47 level on their surface and that there is a high density of tumor-associated macrophages within the microenvironment of human endometrial cancer. In vitro functional assay shows that an anti-CD47 monoclonal antibody (mAb) promotes the phagocytosis of hECCs by macrophages. Systemic and in situ treatments with an anti-CD47 mAb effectively reduce tumor burden in vivo in a genetically engineered mouse model of endometrial cancer. Thus, this study provides preclinical evidence that CD47 blockade using an anti-CD47 mAb to augment macrophage phagocytosis is a potential therapeutic strategy for endometrial cancer.

Transmucosal drug delivery: prospects, challenges, advances, and future directions

INTRODUCTION

Traditional administration routes have limitations including first-pass metabolism and gastrointestinal degradation for sensitive drugs (oral) and pain associated with parenteral injections, which also require trained personnel and refrigeration, making them expensive. This has increased interest in alternative routes, with mucosal surfaces being of high priority.

AREAS COVERED

Mucosal routes include ocular, oral (buccal/sublingual), nasal and vaginal mucosae which avoid the limitations of the oral and parenteral routes. Though mucosal routes show great potential, they are still hindered by several barriers, especially for systemic absorption, resulting in the development of more advanced novel drug delivery systems to overcome these limitations and achieve therapeutic actions both locally and systemically, similar to or exceeding the oral route. This paper systematically reviews and compares the different mucosal routes, challenges, and recent advances in advanced novel drug delivery system design for emerging clinical challenges including the advent of large biological macromolecules (proteins, peptides, and RNA) for treatment and prevention of diseases. The review also focuses on current challenges and future perspectives.

EXPERT OPINION

Among the various transmucosal routes discussed, nose-to-brain drug delivery has the greatest translational potential to go beyond the current state of the art and achieve significant clinical impact for neurological diseases.

A comparison of acceptability of contraceptive vaginal rings, pills, and injectables among cisgender women in Kenya and Zimbabwe: protocol for a mixed-methods study

Background

Expanding contraceptive options could better meet users' diverse needs and preferences. Annovera ® is a contraceptive vaginal ring that provides a year of pregnancy prevention while remaining under user control and allowing for regular menstrual cycles. This method may also help to reduce burdens on some health care and supply chain systems. However, knowledge gaps exist regarding initial and ongoing acceptability of contraceptive vaginal rings in African settings.

Methods

We will undertake an open-label, non-randomized, two-arm, parallel clinical acceptability study with an embedded qualitative component, based in clinics providing contraceptive services in Kenya and Zimbabwe. Women aged 18-45 interested in newly initiating or switching contraception will choose from among all available contraceptive options, including Annovera. We aim to enroll 200 participants selecting Annovera and 200 participants selecting either contraceptive injectables or pills. We will compare method uptake, continuation, and satisfaction over one year. Participants will complete questionnaires administered by study staff during two in-person visits (a screening/enrollment visit, and an end of study visit after 52 weeks of method use or at discontinuation) and four phone appointments (at 4, 12, 24, and 36 weeks of use). We will evaluate used rings for discoloration and residual drug levels. The qualitative component involve in-depth interviews with women in the clinical study, their sexual partners, and their service providers, to further examine drivers of and barriers to interest in and use of contraceptive vaginal rings.

Discussion

This study will explore acceptability of contraceptive vaginal rings in 'real-world' contraceptive service settings in two African countries. Findings will be based on actual ring use and contextualized via comparison to two other commonly available methods. As vaginal rings are being considered for multiple reproductive health indications, this work can fill key knowledge gaps and empower decision-makers with information needed to inform future investments in reproductive health.

Development of Mucoadhesive Vaginal Films for Metronidazole Delivery Using Methacryloylated, Crotonoylated, and Itaconoylated Gelatin Blends with Poly(vinyl alcohol)

PURPOSE

This work reports the development and characterisation of polymeric films composed of gelatin or its chemically modified derivatives (crotonoylated, itaconoylated, and methacryloylated gelatins) blended with polyvinyl alcohol (PVA). Metronidazole served as an antimicrobial drug in these formulations.

METHODS

The films were produced by casting aqueous solutions of polymers, followed by solvent evaporation. Their structure and physicochemical characteristics were studied using Fourier transform infrared spectroscopy, scanning electron microscopy, and mechanical testing. The thickness of the films, their folding endurance, the surface pH, and transparency were also evaluated. The mucoadhesive performance of the films was evaluated through an ex vivo detachment technique involving freshly excised sheep vaginal tissues. In vitro cumulative drug release studies were conducted using Franz diffusion cells.

RESULTS

The results demonstrate that incorporating unsaturated functional groups into gelatin improves its mucoadhesive properties compared to native gelatin. The drug release experiments conducted in vitro showed that the cumulative release from pure gelatin/PVA films was found to be 49 ± 2%, whereas modified gelatins/PVA (70:30) films released ~ 64-71%.

CONCLUSION

These findings suggest that modified gelatins could serve as effective excipients in designing mucoadhesive formulations for vaginal administration, with potential applications extending to other transmucosal drug delivery systems.

Improving the Safety of N,N-Dimethylacetamide (DMA) as a Potential Treatment for Preterm Birth in a Pregnant Mouse Model Using a Vaginal Nanoformulation

Vaginal administration and the uterine first pass effect allow for preferential delivery of drugs to the reproductive tract. Dimethylacetamide has previously been shown to delay preterm birth in a pregnant mouse model when given intraperitoneally but the effectiveness of a vaginal nanoformulation of dimethylacetamide has yet to be tested. The purpose of this study was to compare the two formulations of dimethylacetamide for efficacy in rescuing pups from preterm birth in an inflammation-induced mouse model, effects on the maternal fetal interface, and pharmacokinetic profiles in maternal plasma. Timed pregnant CD1 mice were given a 1.56 mg/kg intraperitoneal dose of lipopolysaccharide followed by 3 doses of either vaginal dimethylacetamide or intraperitoneal dimethylacetamide. Mice were monitored for 48 hours and times of deliveries were recorded. Additionally, CD1 mice in late gestation were given a single dose of either vaginal or intraperitoneal dimethylacetamide and blood was drawn at 3 different time points following administration. Vaginal administration of dimethylacetamide had similar efficacy in delaying inflammation induced preterm birth as intraperitoneal administration but resulted in lower concentrations in the systemic circulation and decreased effects on the maternal fetal interface. Vaginal nanoformulations should be explored for their potential therapeutic value for the delay of preterm birth.

Characterization of HPMC and PEG 400 Mucoadhesive Film Loaded with Retinyl Palmitate and Ketorolac for Intravaginal Administration

Intravaginal drug administration offers several advantages over other routes, primarily bypassing the initial stages of metabolism. Additionally, this route has demonstrated both local and systemic effects. Mucoadhesive polymeric systems can be utilized to prevent dose loss due to the mucous barriers and the formation of wet cavities. This study employed various techniques to evaluate the performance and characteristics of a mucoadhesive film composed of HPMC-PEG 400 containing retinyl palmitate and ketorolac molecules. Scanning Electron Microscopy (SEM) was employed to analyze the porous structure of the film. Thermogravimetric Analysis (TGA) was conducted at different temperatures to assess thermal stability. Fourier Transform Infrared Spectroscopy (FTIR) was used to analyze the functional groups and intermolecular interactions between the film and the drug. Swelling and weight loss tests indicated that the film disintegrated within 3-4 days. UV-VIS spectroscopy was used for drug release evaluation based on the Higuchi equation. Additionally, the surface wetting properties were assessed through contact angle measurements. The system's biocompatibility was confirmed using the MTT assay. Finally, adhesion and glide tests demonstrated the film's interaction with porcine uterine tissue. This study shows that the HPMC-PEG 400 film containing retinyl palmitate molecules interacts effectively with tissue and could be considered a novel tool for treating damaged epithelial tissues.

Safety of topical sildenafil cream, 3.6% in a randomized, placebo-controlled trial for the treatment of female sexual arousal disorder

BACKGROUND

There are currently no Food and Drug Administration-approved treatments for female sexual arousal disorder (FSAD), which is physiologically analogous to male erectile dysfunction.

AIMS

The study sought to test the systemic and local genital safety of topical sildenafil cream, 3.6% (sildenafil cream) among healthy premenopausal women with FSAD and their sexual partners over a 12-week treatment period.

METHODS

This was a phase 2b, exploratory, randomized, placebo-controlled, double-blind study of sildenafil cream among healthy premenopausal women with FSAD. Safety was assessed by the frequency and incidence of treatment-emergent adverse events (TEAEs) among participants and their sexual partners. Participants recorded the incidence of TEAEs in a daily eDiary (electronic diary). Sexual partners were contacted within 72 hours of each sexual event in which investigational product was used. All participants used placebo cream for 1 month, during a single-blind run-in period, and then if eligible, were randomized 1:1 to sildenafil cream or placebo cream. Participants used their assigned investigational product over a 12-week double-blind dosing period. They attended monthly follow-up visits, in which their eDiary TEAE data were reviewed by the study staff and graded for severity and relationship to study product.

OUTCOMES

The frequency and incidence of TEAEs among participants and their sexual partners.

RESULTS

During the 12-week double-blind dosing period, there were 78 TEAEs reported by 29 of 99 sildenafil-assigned participants and 65 TEAEs reported by 28 of 94 placebo-assigned participants (P = .76). All TEAEs were mild or moderate in severity. The most common treatment-related TEAE among active and placebo-assigned participants was application site discomfort. There were no differences in the number of treatment-related TEAEs among sildenafil cream vs placebo cream users (P > .99). Four sildenafil cream participants and 3 placebo cream participants discontinued the study due to TEAEs involving application site discomfort (P > .99). There were 9 TEAEs reported by 7 of 91 sexual partners exposed to sildenafil cream vs 4 TEAEs reported by 4 of 84 sexual partners exposed to placebo cream (P = .54).

CLINICAL IMPLICATIONS

These data support further clinical development of topical sildenafil cream for the treatment of FSAD.

STRENGTHS AND LIMITATIONS

Safety was assessed among participants and their sexual partners after 1357 and 1160 sexual experiences in which sildenafil cream or placebo cream were used, respectively. The phase 2b study was powered for the primary objectives of efficacy, rather than safety.

CONCLUSION

These data demonstrate that topically applied sildenafil cream was safe and well tolerated by exposed users and their sexual partners.

Advanced drug delivery technologies for postmenopausal effects

Postmenopause is the 12-month absence of menstrual periods, characterized by decreased estrogen and progesterone levels, leading to physical and psychological alterations such as hot flashes, mood swings, sleep disruptions, and skin changes. Present postmenopausal treatments include hormone replacement therapy, non-hormonal drugs, lifestyle modifications, vaginal estrogen therapy, bone health treatments, and alternative therapies. Advanced drug delivery systems (ADDSs) are essential in managing postmenopausal effects (PMEs), offering targeted and controlled delivery to alleviate symptoms and improve overall health. This review emphasizes such ADDSs for addressing PMEs. Emerging trends such as artificial ovaries are also reviewed. Additionally, the prospects of technologies such as additive manufacturing (3D and 4D printing) and artificial intelligence in further tailoring therapeutic strategies against PMEs are provided.

Cannabidiol and its application in the treatment of oral diseases: therapeutic potentials, routes of administration and prospects

Cannabidiol (CBD), one of the most important active ingredients in cannabis, has been reported to have some pharmacological effects such as antibacterial and analgesic effects, and to have therapeutic potential in the treatment of oral diseases such as oral cancer, gingivitis and periodontal diseases. However, there is a lack of relevant systematic research and reviews. Therefore, based on the etiology and clinical symptoms of several common oral diseases, this paper focuses on the therapeutic potential of CBD in periodontal diseases, pulp diseases, oral mucosal diseases, oral cancer and temporomandibular joint diseases. The pharmacological effects of CBD and the distribution and function of its receptors in the oral cavity are also summarized. In order to provide reference for future research and further clinical application of CBD, we also summarize several possible routes of administration and corresponding characteristics. Finally, the challenges faced while applying CBD clinically and possible solutions are discussed, and we also look to the future.

Development and verification of mechanistic vaginal absorption and metabolism model to predict systemic exposure after vaginal ring and gel application

AIMS

The current work describes the development of mechanistic vaginal absorption and metabolism model within Simcyp Simulator to predict systemic concentrations following vaginal application of ring and gel formulations.

METHODS

Vaginal and cervix physiology parameters were incorporated in the model development. The study highlights the model assumptions including simulation results comparing systemic concentrations of 5 different compounds, namely, dapivirine, tenofovir, lidocaine, ethinylestradiol and etonogestrel, administered as vaginal ring or gel. Due to lack of data, the vaginal absorption parameters were calculated based on assumptions or optimized. The model uses release rate/in vitro release profiles with formulation characteristics to predict drug mass transfer across vaginal tissue into the systemic circulation.

RESULTS

For lidocaine and tenofovir vaginal gel, the predicted to observed AUC0-t and Cmax ratios were well within 2-fold error limits. The average fold error (AFE) and absolute AFE indicating bias and precision of predictions range from 0.62 to 1.61. For dapivirine, the pharmacokinetic parameters are under and overpredicted in some studies due to lack of formulation composition details and relevance of release rate used in ring model. The predicted to observed AUC0-t and Cmax ratios were well within 2-fold error limits for etonogestrel and ethinylestradiol vaginal ring (AFEs and absolute AFEs from 0.84 to 1.83).

CONCLUSION

The current study provides first of its kind physiologically based pharmacokinetic framework integrating physiology, population and formulation data to carry out in silico mechanistic vaginal absorption studies, with the potential for virtual bioequivalence assessment in the future.

Self-reported removal and expulsion of the dapivirine vaginal ring: qualitative reports from female ring users and their male partners in the Ring Study (IPM 027)

BACKGROUND/AIMS

The dapivirine vaginal ring is a self-administered, women-initiated, discreet, long-acting HIV-1 prevention option for women. It was found to be safe and effective in healthy HIV-negative women who adhered to product use instructions, and has been approved for use in women aged 18 and older in some African countries. A qualitative study was conducted to explore participants' and their male partners' discussions on accidental/purposeful vaginal ring removals during The Ring Study (IPM 027 clinical trial).

METHODS

Data were collected via in-depth interviews and focus group discussions with female trial participants and their male partners, from seven research centres in South Africa and Uganda. Data were thematically analysed using NVivo.

RESULTS

More participants reported purposeful ring removals than accidental expulsions. Various factors influenced purposeful ring removal - including individual (discomfort during use/sex and to clean it), partner (to show them, because of discomfort during sex, to test if partners could feel it, and concerns of harm), organisational (doctor's request), and socio-cultural (rumours about sickness and infertility). Some described their own ring use removal, others discussed why other participants removed their rings.

CONCLUSIONS

Vaginal ring adherence is critical to improve and support product efficacy. Counselling on vaginal anatomy, vaginal ring insertion and importance of adherence is important to minimise vaginal ring removal. Couples counselling is also important to facilitate support and long-term vaginal ring adherence behaviour. Understanding factors influencing vaginal ring adherence is important for tailoring and targeting messages to support correct and consistent vaginal ring use as it is made available to the public.

A Comparative Study and Prediction of the Ex Vivo Permeation of Six Vaginally Administered Drugs across Five Artificial Membranes and Vaginal Tissue

The theoretical interpretation of the vaginal permeability phenomenon, the evaluation of the suitability of five artificial membranes, and the prediction of the behaviors of vaginal drugs were the main objectives of this study. Franz vertical diffusion cells and different validated HPLC methods were used to measure the permeability of six vaginally administered drugs (econazole, miconazole, metronidazole, clindamycin, lidocaine, and nonoxynol-9). This study was performed (in vitro) on different membranes of polyvinylidene fluoride (PVDF), plain cellulose or cellulose impregnated with isopropyl myristate (IPM), and cellulose combined with PVDF or IPM. The results were compared with those obtained from cow vaginal tissue (ex vivo), where cellulose was proven to be the best simulant. According to the permeability profiles (Papp), the water solubility of the drugs was considered a necessary criterion for their transport in the membranes or in the tissue, while the size was important for their penetration. Furthermore, it was found that polar compounds show clear superiority when penetrating cellulose or tissue, while non-polar ones show superiority when penetrating the lipophilic PVDF membrane. Finally, a successful attempt was made to predict the Papp values (|Papp-predPapp| < 0.005) of the six drugs under study based on a PLS (Partial Least Squares) in silico simulation model.

Commercial hydrogel product for drug delivery based on route of administration

Hydrogels are hydrophilic, three-dimensional, cross-linked polymers that absorb significant amounts of biological fluids or water. Hydrogels possess several favorable properties, including flexibility, stimulus-responsiveness, versatility, and structural composition. They can be categorized according to their sources, synthesis route, response to stimulus, and application. Controlling the cross-link density matrix and the hydrogels' attraction to water while they're swelling makes it easy to change their porous structure, which makes them ideal for drug delivery. Hydrogel in drug delivery can be achieved by various routes involving injectable, oral, buccal, vaginal, ocular, and transdermal administration routes. The hydrogel market is expected to grow from its 2019 valuation of USD 22.1 billion to USD 31.4 billion by 2027. Commercial hydrogels are helpful for various drug delivery applications, such as transdermal patches with controlled release characteristics, stimuli-responsive hydrogels for oral administration, and localized delivery via parenteral means. Here, we are mainly focused on the commercial hydrogel products used for drug delivery based on the described route of administration.

First-in-human study to assess the pharmacokinetics, tolerability, and safety of single-dose oxybutynin hydrochloride administered via a microprocessor-controlled intravaginal ring

Polymeric drug-releasing vaginal rings are useful for both local and systemic administration of drugs via the intravaginal route. Typically, they provide continuous sustained or controlled release of drug(s) over extended time periods, thereby avoiding overdose and improving adherence. This first-in-human study (EudraCT number: 2020-0050044-30) evaluated the pharmacokinetics, safety, and tolerability of a single dose of oxybutynin administered by a novel microprocessor-controlled vaginal ring (MedRing). Eight healthy female subjects received an electronically controlled single intravaginal dose of 3 mg oxybutynin hydrochloride (100 mg/mL) dissolved in 1:1 water/propylene glycol administered via MedRing. Following dosing, MedRing was kept in situ for up to 6 h. Blood samples were collected 1 h prior to oxybutynin dosing and subsequently at regular intervals post-dose for the assessment of plasma concentrations of oxybutynin and its active metabolite N-desethyloxybutynin. The results showed that MedRing efficiently administered oxybutynin via the intravaginal route, resulting in plasma oxybutynin levels comparable to orally administered oxybutynin. The mean ± standard deviation pharmacokinetic parameters for oxybutynin were Cmax 5.4 ± 2.7 ng/mL, AUCinf 34.9 ± 17.4 h ng/mL, t1/2 8.5 ± 3.5 h and for N-desethyloxybutynin were Cmax 3.9 ± 2.5 ng/mL, AUCinf 51.1 ± 43.1 h ng/mL, t1/2 7.7 ± 5.9 h. No serious adverse events were reported. The study demonstrates that intravaginal administration of oxybutynin hydrochloride using the MedRing device was well tolerated.

Comparing the Effect of Probiotic and Fluconazole on Treatment and Recurrence of Vulvovaginal Candidiasis: a Triple-Blinded Randomized Controlled Trial

Vaginitis is a common problem in women. Candida albicans is responsible for more than 85% of vaginal fungal infections. The aim of this study was to compare the effects of probiotic and fluconazole on the treatment and recurrence of vulvovaginal candidiasis (VVC). This triple-blinded randomized controlled trial was conducted on 80 married women, aged 18-49 years, with VVC, as confirmed by clinical and laboratory diagnosis. The participants were allocated into two groups using blocked randomization method. The fluconazole-treated group received a single dose of fluconazole (150 mg) supplemented with 30 placebo capsules of probiotic, and the probiotic-treated group got 30 probiotic capsules containing 1 × 109 CFU/g LA-5 with 1 fluconazole placebo capsule. The samples were taken from patients to evaluate the vaginal pH and microbiological tests before, 30-35 days, and 60-65 days after starting the treatment. The signs and symptoms were assessed before the intervention and the first and second follow-ups. Chi-square, Fisher's exact, independent t, and ANCOVA tests were then used for data analysis. There was no statistically significant difference between the two groups (p = 0.127) in the frequency of negative culture 30-35 days after starting the treatment, but the frequency of negative culture 60-65 days after starting treatment in the fluconazole group was significantly higher than that of the probiotic group (p = 0.016). The abnormal discharge and vulvovaginal erythema in the first and second follow-ups and also pruritus in the second follow-up in the fluconazole group were significantly lower than those in the probiotic group (p < 0.05). There was, however, no statistically significant difference in burning, frequent urination, dysuria, and dyspareunia between the groups (p > 0.05). Lactobacillus acidophilus supplementation had an effect similar to that of fluconazole in treating most symptoms of VVC, but it was less effective than the latter in preventing recurrence. Trial Registration: Iranian Registry of Clinical Trials (IRCT): IRCT20110826007418N5. Date of registration: 3 March 2021; URL: https://en.irct.ir/trial/50819 ; Date of first registration: 10 March 2021.

Mucoadhesive 3D printed vaginal ovules to treat endometriosis and fibrotic uterine diseases

Gynaecological health is a neglected field of research that includes conditions such as endometriosis, uterine fibroids, infertility, viral and bacterial infections, and cancers. There is a clinical need to develop dosage forms for gynecological diseases that increase efficacy and reduce side effects and explore new materials with properties tailored to the vaginal mucosa and milieu. Here, we developed a 3D printed semisolid vaginal ovule containing pirfenidone, a repurposed drug candidate for endometriosis. Vaginal drug delivery allows direct targeting of the reproductive organs via the first uterine pass effect, but vaginal dosage forms can be challenging to self-administer and retain in situ for periods of more than 1-3 h. We show that a semisoft alginate-based vaginal suppository manufactured using semisolid extrusion additive manufacturing is superior to vaginal ovules made using standard excipients. The 3D-printed ovule showed a controlled release profile of pirfenidone in vitro in standard and biorelevant release tests, as well as better mucoadhesive properties ex vivo. An exposure time of 24 h of pirfenidone to a monolayer culture of an endometriotic epithelial cell line, 12Z, is necessary to reduce the cells' metabolic activity, which demonstrates the need for a sustained release formulation of pirfenidone. 3D printing allowed us to formulate mucoadhesive polymers into a semisolid ovule with controlled release of pirfenidone. This work enables further preclinical and clinical studies into vaginally administered pirfenidone to assess its efficacy as a repurposed endometriosis treatment.

Advances in progesterone delivery systems: Still work in progress?

Progesterone is a natural steroidal sex hormone in the human body, mainly secreted through the adrenal cortex, ovary, and placenta. In humans, progesterone is essential for endometrium transformation in the uterus at the time of ovulation and maintenance of pregnancy. When the body cannot produce enough progesterone for specific ailments, it is administered via different routes such as oral, vaginal, transdermal, topical, parental, and intranasal routes. Although progesterone is commercially available in multiple conventional formulations, low solubility, less permeability and extensive hepatic first-pass metabolism are the major constraints to its delivery. These challenges can be overcome substantially by formulating progesterone into novel delivery systems like lipid carriers, polymeric carriers, hydrogels, several nanocarriers, depot and controlled release systems. Various research papers and patents have been published in the last two decades on progesterone delivery systems; clinical studies were conducted to establish safety and efficacy. This review is focused on the pharmacodynamic and pharmacokinetic parameters of progesterone, its delivery constraints, and various advanced delivery systems of progesterone.

Nanomedicine strategies to improve therapeutic agents for the prevention and treatment of preterm birth and future directions

The World Health Organisation (WHO) estimates 15 million babies worldwide are born preterm each year, with 1 million infant mortalities and long-term morbidity in survivors. Whilst the past 40 years have provided some understanding in the causes of preterm birth, along with development of a range of therapeutic options, notably prophylactic use of progesterone or uterine contraction suppressants (tocolytics), the number of preterm births continues to rise. Existing therapeutics used to control uterine contractions are restricted in their clinical use due to pharmacological drawbacks such as poor potency, transfer of drugs to the fetus across the placenta and maternal side effects from activity in other maternal systems. This review focuses on addressing the urgent need for the development of alternative therapeutic systems with improved efficacy and safety for the treatment of preterm birth. We discuss the application of nanomedicine as a viable opportunity to engineer pre-existing tocolytic agents and progestogens into nanoformulations, to improve their efficacy and address current drawbacks to their use. We review different nanomedicines including liposomes, lipid-based carriers, polymers and nanosuspensions highlighting where possible, where these technologies have already been exploited e.g. liposomes, and their significance in improving the properties of pre-existing therapeutic agents within the field of obstetrics. We also highlight where active pharmaceutical agents (APIs) with tocolytic properties have been used for other clinical indications and how these could inform the design of future therapeutics or be repurposed to diversify their application such as for use in preterm birth. Finally we outline and discuss the future challenges.

Lipid-core nanoparticles: Classification, preparation methods, routes of administration and recent advances in cancer treatment

Nanotechnological drug delivery platforms represent a new paradigm for cancer therapeutics as they improve the pharmacokinetic profile and distribution of chemotherapeutic agents over conventional formulations. Among nanoparticles, lipid-based nanoplatforms possessing a lipid core, that is, lipid-core nanoparticles (LCNPs), have gained increasing interest due to lipid properties such as high solubilizing potential, versatility, biocompatibility, and biodegradability. However, due to the wide spectrum of morphologies and types of LCNPs, there is a lack of consensus regarding their terminology and classification. According to the current state-of-the-art in this critical review, LCNPs are defined and classified based on the state of their lipidic components in liquid lipid nanoparticles (LLNs). These include lipid nanoemulsions (LNEs) and lipid nanocapsules (LNCs), solid lipid nanoparticles (SLNs) and nanostructured lipid nanocarriers (NLCs). In addition, we present a comprehensive and comparative description of the methods employed for their preparation, routes of administration and the fundamental role of physicochemical properties of LCNPs for efficient antitumoral drug-delivery application. Market available LCNPs, clinical trials and preclinical in vivo studies of promising LCNPs as potential treatments for different cancer pathologies are summarized.

Stimuli-Responsive Boron-Based Materials in Drug Delivery

Drug delivery systems, which use components at the nanoscale level as diagnostic tools or to release therapeutic drugs to particular target areas in a regulated manner, are a fast-evolving field of science. The active pharmaceutical substance can be released via the drug delivery system to produce the desired therapeutic effect. The poor bioavailability and irregular plasma drug levels of conventional drug delivery systems (tablets, capsules, syrups, etc.) prevent them from achieving sustained delivery. The entire therapy process may be ineffective without a reliable delivery system. To achieve optimal safety and effectiveness, the drug must also be administered at a precision-controlled rate and the targeted spot. The issues with traditional drug delivery are overcome by the development of stimuli-responsive controlled drug release. Over the past decades, regulated drug delivery has evolved considerably, progressing from large- and nanoscale to smart-controlled drug delivery for several diseases. The current review provides an updated overview of recent developments in the field of stimuli-responsive boron-based materials in drug delivery for various diseases. Boron-containing compounds such as boron nitride, boronic acid, and boron dipyrromethene have been developed as a moving field of research in drug delivery. Due to their ability to achieve precise control over drug release through the response to particular stimuli (pH, light, glutathione, glucose or temperature), stimuli-responsive nanoscale drug delivery systems are attracting a lot of attention. The potential of developing their capabilities to a wide range of nanoscale systems, such as nanoparticles, nanosheets/nanospheres, nanotubes, nanocarriers, microneedles, nanocapsules, hydrogel, nanoassembly, etc., is also addressed and examined. This review also provides overall design principles to include stimuli-responsive boron nanomaterial-based drug delivery systems, which might inspire new concepts and applications.

Pain Specialist Management of Sexual Pain-II: Interventional

INTRODUCTION

Treatment of female sexual pain often requires the use of diverse modalities crossing multiple medical disciplines. Interventional procedures are important in the diagnosis and treatment of female sexual pain. Pain specialists and other medical specialties can provide these capabilities.

OBJECTIVES

To provide a current summary of the procedures used in the diagnosis and treatment of female sexual pain.

METHODS

The internet, PubMed, and the Cochrane Library were searched for relevant articles on female sexual pain within the clinical purview and scope of the practice of pain management.

RESULTS

A thorough review of the literature was conducted to include basic science studies, clinical trials, systematic reviews, consensus statements, and case reports. An effort was made to also include a sampling of information on real-world patient self-directed therapies. Descriptions of interventional procedures for the diagnosis and treatment of sexual pain were made and clinical studies reviewed. The evidence for the use of various interventional treatment strategies for sexual pain was assessed.

CONCLUSIONS

The process of care for female sexual pain employs an interdisciplinary biopsychosocial model that includes a role for interventional procedures commonly performed by pain management specialists. These specialists are a resource of knowledge, skills, and abilities that can be used to improve the care of women with chronic sexual pain.

A phase I study to assess safety, pharmacokinetics, and pharmacodynamics of a vaginal insert containing tenofovir alafenamide and elvitegravir

Background

New multi-purpose prevention technology (MPT) products are needed to prevent human immunodeficiency virus (HIV) and herpes simplex virus type 2 (HSV2). In this study, we evaluated a fast-dissolve insert that may be used vaginally or rectally for prevention of infection.

Objective

To describe the safety, acceptability, multi-compartment pharmacokinetics (PK), and in vitro modeled pharmacodynamics (PD) after a single vaginal dose of an insert containing tenofovir alafenamide (TAF) and elvitegravir (EVG) in healthy women.

Methods

This was a Phase I, open-label, study. Women (n=16) applied one TAF (20mg)/EVG (16mg) vaginal insert and were randomized (1:1) to sample collection time groups for up to 7 days post dosing. Safety was assessed by treatment-emergent adverse events (TEAEs). EVG, TAF and tenofovir (TFV) concentrations were measured in plasma, vaginal fluid and tissue, and TFV-diphosphate (TFV-DP) concentration in vaginal tissue. PD was modeled in vitro by quantifying the change in inhibitory activity of vaginal fluid and vaginal tissue against HIV and HSV2 from baseline to after treatment. Acceptability data was collected by a quantitative survey at baseline and post treatment.

Results

The TAF/EVG insert was safe, with all TEAEs graded as mild, and acceptable to participants. Systemic plasma exposure was low, consistent with topical delivery, while high mucosal levels were detected, with median TFV vaginal fluid concentrations exceeding 200,000 ng/mL and 1,000 ng/mL for up to 24 hours and 7 days post dosing, respectively. All participants had vaginal tissue EVG concentrations of > 1 ng/mg at 4 and 24 hours post dosing. The majority had tissue TFV-DP concentrations exceeding 1000 fmol/mg by 24 - 72 hours post dosing. Vaginal fluid inhibition of HIV-1 and HSV-2 in vitro significantly increased from baseline and was similarly high at 4 and 24 hours post dosing. Consistent with high tissue TFV-DP concentrations, p24 HIV antigen production from ectocervical tissues infected ex vivo with HIV-1 significantly decreased from baseline at 4 hours post dosing. HSV-2 production from tissue also decreased post treatment.

Conclusions

A single dose of TAF/EVG inserts met PK benchmarks, with PK data supporting an extended window of high mucosal protection. PD modeling supports mucosal protection against both HIV-1 and HSV-2. The inserts were safe and highly acceptable.

Clinical trial registration

ClinicalTrials.gov, identifier NCT03762772.

Novel Mucoadhesive Wafers for Treating Local Vaginal Infections

Current vaginal formulations, such as gels and pessaries, have limitations, including poor retention. Therefore, the use of mucoadhesive formulations that adhere to the vaginal wall would allow prolonged retention and controlled drug release while reducing the required dose and the potential toxicity associated with high drug loading. The aim of the current research was to develop, characterize, and optimize freeze-dried wafers loaded with metronidazole (MTz) to treat vaginal bacterial infections. Blank (BLK) composite wafers comprising carrageenan (CARR) and sodium alginate (SA) were initially formulated; however, due to poor physico-chemical properties, Carbopol (CARB), hydroxypropylmethylcellulose (HPMC), and polyethylene glycol 200 (PEG) were included. The MTz-loaded formulations were obtained by loading optimized composite CARB:CARR- or CARB:SA-based gels (modified with HPMC and/or PEG) with 0.75% of MTz prior to freeze-drying. The physico-chemical properties were investigated using texture analysis (resistance to compressive deformation and adhesion), scanning electron microscopy (SEM), X-ray diffractometry (XRD), and attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy. Functional properties were investigated by examining the swelling, porosity, drug release, and in vitro antimicrobial activity using E. coli as a model infection-causative agent. The results showed that HPMC and PEG generally improved the wafer's appearance, with smoother surfaces for easy insertion. From the physico-chemical characterization studies, only two composite wafers prepared from 8% CARB:SA 1:4 and 8% CARB:SA 1:9 gels were deemed optimal and loaded with MTz. Both formulations showed sustained drug release and achieved almost 100% cumulative release within 72 h in simulated vaginal fluid. The data obtained from the drug dissolution (release) experiments were fitted to various mathematical equations and showed the highest correlation coefficient with the Higuchi equation, suggesting a drug release based on diffusion from a swollen matrix; this was confirmed by the Korsmeyer-Peppas equation. The released MTz inhibited the growth of the E. coli used as a model bacterial organism.

Absorbable Electrospun Poly-4-hydroxybutyrate Scaffolds as a Potential Solution for Pelvic Organ Prolapse Surgery

Women with pelvic organ prolapse (POP) have bothersome complaints that significantly affect their quality of life. While native tissue repair is associated with high recurrence rates, polypropylene knitted implants have caused specific implant-related adverse events that have detrimental, often irreversible, effects. We hypothesize that surgical outcome can be improved with a tissue-engineered solution using an absorbable implant that mimics the natural extracellular matrix (ECM) structure, releases estrogen, and activates collagen metabolism by fibroblasts as the main regulators of wound healing. To this aim, we produced electrospun poly-4-hydroxybutyrate (P4HB) scaffolds and biofunctionalized them with estradiol (E2). The cell-implant interactions relevant for POP repair were assessed by seeding primary POP vaginal fibroblasts isolated from patients on electrospun P4HB scaffolds with 1%, 2%, or 5% E2 and without E2. To test our hypothesis on whether ECM mimicking structures should improve regeneration, electrospun P4HB was compared to knitted P4HB implants. We evaluated vaginal fibroblast proliferation, ECM deposition, and metabolism by quantification of collagen, elastin, and matrix metalloproteinases and by gene expression analysis for 28 days. We established effective E2 drug loading with a steady release over time. Significantly higher cell proliferation, collagen-, and elastin deposition were observed on electrospun P4HB scaffolds as compared to knitted P4HB. For this study, physical properties of the scaffolds were more determinant on the cell response than the release of E2. These results indicate that making these electrospun P4HB scaffolds E2-releasing appears to be technically feasible. In addition, electrospun P4HB scaffolds promote the cellular response of vaginal fibroblasts and further studies are merited to assess if their use results in improved surgical outcomes in case of POP repair.

Vaginal Nanoformulations for the Management of Preterm Birth

Preterm birth (PTB) is a leading cause of infant morbidity and mortality in the world. In 2020, 1 in 10 infants were born prematurely in the United States. The World Health Organization estimates that a total of 15 million infants are born prematurely every year. Current therapeutic interventions for PTB have had limited replicable success. Recent advancements in the field of nanomedicine have made it possible to utilize the vaginal administration route to effectively and locally deliver drugs to the female reproductive tract. Additionally, studies using murine models have provided important insights about the cervix as a gatekeeper for pregnancy and parturition. With these recent developments, the field of reproductive biology is on the cusp of a paradigm shift in the context of treating PTB. The present review focuses on the complexities associated with treating the condition and novel therapeutics that have produced promising results in preclinical studies.

Advances and future perspectives in epithelial drug delivery

Epithelial surfaces protect exposed tissues in the body against intrusion of foreign materials, including xenobiotics, pollen and microbiota. The relative permeability of the various epithelia reflects their extent of exposure to the external environment and is in the ranking: intestinal≈ nasal ≥ bronchial ≥ tracheal > vaginal ≥ rectal > blood-perilymph barrier (otic), corneal > buccal > skin. Each epithelium also varies in their morphology, biochemistry, physiology, immunology and external fluid in line with their function. Each epithelium is also used as drug delivery sites to treat local conditions and, in some cases, for systemic delivery. The associated delivery systems have had to evolve to enable the delivery of larger drugs and biologicals, such as peptides, proteins, antibodies and biologicals and now include a range of physical, chemical, electrical, light, sound and other enhancement technologies. In addition, the quality-by-design approach to product regulation and the growth of generic products have also fostered advancement in epithelial drug delivery systems.

Ovarian Follicular Growth through Intermittent Vaginal Gonadotropin Administration in Diminished Ovarian Reserve Women

It is a challenge to obtain enough oocytes during in vitro fertilization (IVF) in women who have a poor ovarian response (POR) in achieving conception. We have adopted the characteristics of the first uterine pass effect, which we pioneered in employing the vaginal administration of gonadotropins in women receiving IVF treatments. In our previous study employing vaginal administration, faster absorption and slower elimination of gonadotropins were demonstrated, and, female subjects presented proper ovarian follicle growth and pregnancy rates. In this study, during 2016–2020, 300 to 675 IU of gonadotropins were administered vaginally every three days in 266 POR women for their controlled ovarian hyperstimulation (COH). The injections were performed with needles angled at 15–30° towards the middle-upper portions of the bilateral vaginal wall, with an injection depth of 1–2 mm. For the COH results, these women, on average, received 3.0 ± 0.9 vaginal injections and a total dose of 1318.4 ± 634.4 IU gonadotropins, resulting in 2.2 ± 1.9 mature oocytes and 1.0 ± 1.2 good embryos. Among these embryos, 0.9 ± 1.0 were transferred to reach a clinical pregnancy rate of 18.1% and a live birth rate of 16.7%. In conclusion, the intermittent vaginal administration of gonadotropins proved to be effective in POR women for their IVF treatments.

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.

Application of Sol–Gels for Treatment of Gynaecological Conditions—Physiological Perspectives and Emerging Concepts in Intravaginal Drug Delivery

Approaches for effective and sustained drug delivery to the female reproductive tract (FRT) for treating a range of gynaecological conditions remain limited. The development of versatile delivery platforms, such as soluble gels (sol–gels) coupled with applicators/devices, holds considerable therapeutic potential for gynaecological conditions. Sol–gel systems, which undergo solution-to-gel transition, triggered by physiological conditions such as changes in temperature, pH, or ion composition, offer advantages of both solution- and gel-based drug formulations. Furthermore, they have potential to be used as a suitable drug delivery vehicle for other novel drug formulations, including micro- and nano-particulate systems, enabling the delivery of drug molecules of diverse physicochemical character. We provide an anatomical and physiological perspective of the significant challenges and opportunities in attaining optimal drug delivery to the upper and lower FRT. Discussion then focuses on attributes of sol–gels that can vastly improve the treatment of gynaecological conditions. The review concludes by showcasing recent advances in vaginal formulation design, and proposes novel formulation strategies enabling the infusion of a wide range of therapeutics into sol–gels, paving the way for patient-friendly treatment regimens for acute and chronic FRT-related conditions such as bacterial/viral infection control (e.g., STDs), contraception, hormone replacement therapy (HRT), infertility, and cancer.

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.

Recent Advances in the Excipients Used in Modified Release Vaginal Formulations

The formulation of an ideal vaginal drug delivery system (DDS), with the requisite properties, with respect to safety, efficacy, patient compliance, aesthetics, harmonization with the regulatory requirements, and cost, requires a meticulous selection of the active ingredients and the excipients used. Novel excipients defined by diversity and multifunctionality are used in order to ameliorate drug delivery attributes. Synthetic and natural polymers are broadly used in pharmaceutical vaginal formulations (solid, semi-solid dosage forms, implantable devices, and nanomedicines) with a promising perspective in improving stability and compatibility issues when administered topically or systemically. Moreover, the use of biopolymers is aiming towards formulating novel bioactive, biocompatible, and biodegradable DDSs with a controllable drug release rate. Overviewing vaginal microenvironment, which is described by variable and perplexed features, a perceptive choice of excipients is essential. This review summarizes the recent advances on the excipients used in modified vaginal drug delivery formulations, in an attempt to aid the formulation scientist in selecting the optimal excipients for the preparation of vaginal products.

Genital Mucosal Drug Concentrations and anti-HIV Activity in Tenofovir-Based PrEP Products: Intravaginal Ring vs. Oral Administration

OBJECTIVE

To describe and compare systemic and local pharmacokinetics (PK) and cervicovaginal (CV) pharmacodynamics (PD) of oral tenofovir disoproxil fumarate (TDF) in combination with emtricitabine (FTC) with tenofovir (TFV) intravaginal ring (IVR).

DESIGN

Phase I, randomized, parallel-group study. Women (n = 22) used TDF/FTC oral tablets daily or TFV IVR continuously and were assessed at baseline and 14 days.

METHODS

TFV and FTC concentrations were measured in plasma, CV fluid (CVF), and CV tissue. TFV-diphosphate and FTC-triphosphate were assessed in CV tissue. In vitro PD antiviral activities of TFV and FTC (using in vivo concentration ranges) were modeled in the CVF and by infecting CV tissue explants ex vivo with HIV-1BaL.

RESULTS

Adverse events (AEs) were more common with oral TDF/FTC use (P < 0.01). The median CVF TFV concentrations were 106 ng/mL after use of TFV IVR vs. 102 ng/mL for TDF/FTC. The median TFV and TFV-diphosphate concentrations in CV tissue were >100-fold higher among IVR users. The median CVF FTC concentrations were 103 ng/mL. FTC and FTC-triphosphate were detected in all CV tissues from TDF/FTC users. HIV inhibitory activity of CVF increased significantly with treatment in both cohorts (P < 0.01) but was higher in TFV IVR users (P < 0.01). In vitro inhibition of tissue infection with ex vivo administration of TFV and FTC was dose dependent, with maximal efficacy achieved with 10 µg/mL TFV, 1 µg/mL FTC, and 0.1 µg/mL of TFV and FTC combined.

CONCLUSIONS

Both products were safe and increased mucosal HIV inhibitory activity. In addition to systemic protection, oral TDF/FTC displays a PK/PD profile compatible with CV mucosal antiviral activity. TFV IVR resulted in fewer AEs, lower TFV plasma concentrations, higher CVF and tissue TFV and TFV-DP concentrations, and greater anti-HIV activity in CVF.

Women's experiences using drugs to induce abortion acquired in the informal sector in Colombia: qualitative interviews with users in Bogotá and the Coffee Axis

In 2006, abortion in Colombia was decriminalised under certain circumstances. Yet some women continue to avail themselves of ways to terminate pregnancies outside of the formal health system. In-depth interviews (IDIs) with women who acquired drugs outside of health facilities to terminate their pregnancies (n = 47) were conducted in Bogotá and the Coffee Axis in 2018. Respondents were recruited when they sought postabortion care at a health facility. This analysis examines women's experiences with medication acquired outside of the health system for a termination: how they obtained the medication, what they received, how they were instructed to use the pills, the symptoms they were told to expect, and their abortion experiences. Respondents purchased the drugs in drug stores, online, from street vendors, or through contacts in their social networks. Women who used online vendors more commonly received the minimum dose of misoprostol according to WHO guidelines to complete the abortion (800 mcg) and received more detailed instructions and information about what to expect than women who bought the drug elsewhere. Common instructions were to take the pills orally and vaginally; most women received incomplete information about what to expect. Most women seeking care did not have a complete abortion before coming to the health facility (they never started bleeding or had an incomplete abortion). Women still face multiple barriers to safe abortion in Colombia; policymakers should promote better awareness about legal abortion availability, access to quality medication and complete information about misoprostol use for women to terminate unwanted pregnancies safely.

Recent advances in electrospun nanofiber vaginal formulations for women's sexual and reproductive health

Electrospinning is an innovative technique that allows production of nanofibers and microfibers by applying a high voltage to polymer solutions of melts. The properties of these fibers - which include high surface area, high drug loading capacity, and ability to be manufactured from mucoadhesive polymers - may be particularly useful in a myriad of drug delivery and tissue engineering applications. The last decade has witnessed a surge of interest in the application of electrospinning technology for the fabrication of vaginal drug delivery systems for the treatment and prevention of diseases associated with women's sexual and reproductive health, including sexually transmitted infections (e.g. infection with human immunodeficiency virus and herpes simplex virus) vaginitis, preterm birth, contraception, multipurpose prevention technology strategies, cervicovaginal cancer, and general maintenance of vaginal health. Due to their excellent mechanical properties, electrospun scaffolds are also being investigated as next-generation materials in the surgical treatment of pelvic organ prolapse. In this article, we review the latest advances in the field.

Women-specific routes of administration for drugs: A critical overview

The woman's body presents a number of unique anatomical features that can constitute valuable routes for the administration of drugs, either for local or systemic action. These are associated with genitalia (vaginal, endocervical, intrauterine, intrafallopian and intraovarian routes), changes occurring during pregnancy (extra-amniotic, intra-amniotic and intraplacental routes) and the female breast (breast intraductal route). While the vaginal administration of drug products is common, other routes have limited clinical application and are fairly unknown even for scientists involved in drug delivery science. Understanding the possibilities and limitations of women-specific routes is of key importance for the development of new preventative, diagnostic and therapeutic strategies that will ultimately contribute to the advancement of women's health. This article provides an overview on women-specific routes for the administration of drugs, focusing on aspects such as biological features pertaining to drug delivery, relevance in current clinical practice, available drug dosage forms/delivery systems and administration techniques, as well as recent trends in the field.

3D Printing of Pharmaceutical Application: Drug Screening and Drug Delivery

Advances in three-dimensional (3D) printing techniques and the development of tailored biomaterials have facilitated the precise fabrication of biological components and complex 3D geometrics over the past few decades. Moreover, the notable growth of 3D printing has facilitated pharmaceutical applications, enabling the development of customized drug screening and drug delivery systems for individual patients, breaking away from conventional approaches that primarily rely on transgenic animal experiments and mass production. This review provides an extensive overview of 3D printing research applied to drug screening and drug delivery systems that represent pharmaceutical applications. We classify several elements required by each application for advanced pharmaceutical techniques and briefly describe state-of-the-art 3D printing technology consisting of cells, bioinks, and printing strategies that satisfy requirements. Furthermore, we discuss the limitations of traditional approaches by providing concrete examples of drug screening (organoid, organ-on-a-chip, and tissue/organ equivalent) and drug delivery systems (oral/vaginal/rectal and transdermal/surgical drug delivery), followed by the introduction of recent pharmaceutical investigations using 3D printing-based strategies to overcome these challenges.

Use of Hormone Therapy in Postmenopausal Women with Alzheimer's Disease: A Systematic Review

BACKGROUND

Around two-thirds of patients with Alzheimer's disease (AD) are women, which could be related to the depletion of female sexual hormones at menopause. The replacement of these hormones with hormone therapy (HT) to possibly decrease AD risk or treat AD patients has generated conflicting results in the literature.

OBJECTIVE

Our aim was to systematically review the relationship between HT use in postmenopausal women with AD and the risk of developing or treating AD symptoms.

DATA SOURCES

The PubMed, LILACS, Scopus, Scielo, and Web of Science databases were searched from January 1994 to December 2020 using the descriptors 'Alzheimer Disease OR Alzheimer's Disease' and 'Hormone Replacement Therapy OR Estrogen Replacement Therapy'.

STUDY SELECTION

Observational and controlled clinical trials including postmenopausal women diagnosed with AD and evaluating HT efficacy were eligible for inclusion.

DATA EXTRACTION

Extracted data comprise study design, covariates, inclusion criteria for sample selection, AD diagnosis criteria, biases, HT regimen, and cognitive measurement tools used.

RESULTS

Overall, 25 studies were selected. Among the 14 observational studies, 8 reported an improvement in cognitive function and a decrease in AD risk, especially in younger postmenopausal women. Five observational studies did not demonstrate any association between HT and AD, and one study reported an increase in AD risk, regardless of time of HT initiation. Of the 11 controlled clinical trials included, 7 showed an amelioration in cognitive function after HT. The remaining 4 trials saw no difference between HT and control.

CONCLUSION

Both observational and controlled clinical trials had methodological issues and discrepancies in inclusion criteria and HT protocols. These inconsistencies made it difficult to establish an association between HT and AD.

Emulsion-Based Multicompartment Vaginal Drug Carriers: From Nanoemulsions to Nanoemulgels

In order to overcome the limitations associated with vaginal administration of drugs, e.g., the short contact time of the drug form with the mucosa or continuous carrier wash-out, the development of new carriers for gynecological use is necessary. Furthermore, high individual anatomical and physiological variability resulting in unsatisfactory therapeutic efficacy of lipophilic active substances requires application of multicompartment drug delivery systems. This manuscript provides an up-to-date comprehensive review of the literature on emulsion-based vaginal dosage forms (EVDF) including macroemulsions, microemulsions, nanoemulsions, multiple emulsions and self-emulsifying drug delivery systems. The first part of the paper discusses (i) the influence of anatomical-physiological conditions on therapeutic efficacy of drug forms after local and systemic administration, (ii) characterization of EVDF components and the manufacturing techniques of these dosage forms and (iii) methods used to evaluate the physicochemical and pharmaceutical properties of emulsion-based vaginal dosage forms. The second part of the paper presents (iv) the results of biological and in vivo studies as well as (v) clinical evaluation of EVDF safety and therapeutic efficacy across different indications.

Use of dopamine agonists to target angiogenesis in women with endometriosis

Endometriosis requires medical management during a woman's reproductive years. Most treatments aim to create a hypoestrogenic milieu, but for patients wishing to conceive, drugs that allow normal ovarian function are needed. Targeting angiogenesis, a hallmark of the disease, using dopamine agonists (DAs) is a promising strategy for endometriosis treatment. Herein, we review experimental and clinical data that investigate this concept. In experimental models of endometriosis, DAs (bromocriptine, cabergoline, quinagolide) downregulate proangiogenic and upregulate antiangiogenic pathways in inflammatory, endothelial and endometrial cells, blocking cellular proliferation and reducing lesion size. Impaired secretion of vascular endothelial growth factor (VEGF) and inactivation of its receptor type-2 are key events. VEGF inhibition also reduces nerve fiber density in lesions. In humans, quinagolide shows similar effects on lesions, and DAs reduce pain and endometrioma size. Moreover, a 20-fold downregulation of Serpin-1, the gene that encodes for plasminogen activator inhibitor 1 (PAI-1), has been observed after DAs treatment. Pentoxifylline, a PAI-1, increases pregnancy rates in women with endometriosis. Thus, the data support the use of DAs in the medical management of endometriosis to reduce lesion size and pain while maintaining ovulation. A combined approach of DAs and pentoxifylline is perhaps a smart way of targeting the disease from a completely different angle than current medical treatments.

Drug Delivery Approaches for Managing Overactive Bladder (OAB): A Systematic Review

Overactive bladder syndrome (OAB) is characterised by urgency symptoms, with or without urgency incontinence, usually with frequency and nocturia and severely affects the quality of life. This systematic review evaluates the various drug delivery strategies used in practice to manage OAB. Advanced drug delivery strategies alongside traditional strategies were comprehensively analysed and comparatively evaluated. The present review was conducted according to the preferred reporting items for systematic reviews and meta-analyses guidelines. A total of 24 studies reporting the development of novel formulations for the treatment of OAB were considered eligible and were further categorised according to the route of drug administration. The review found that various drug delivery routes (transdermal, intravesicular, oral, vaginal and intramuscular) are used for the administration of drugs for managing OAB, however, the outcomes illustrated the marked potential of transdermal drug delivery route. The findings of the current review are expected to be helpful for pharmaceutical scientists to better comprehend the existing literature and challenges and is anticipated to provide a basis for designing and fabricating novel drug delivery systems to manage OAB.

The effect of different contraceptive methods on the vaginal microbiome

Introduction: Following a historical overview, the effect of different contraceptive methods on vaginal microbiome has been reviewed and summarized.Areas covered: Effects of combined hormonal contraceptives (oral or vaginal) and of progestin only (injectable and implantable), intrauterine devices/systems (copper- or levonorgestrel-releasing), on vaginal microbiome. In addition, mention is made of vaginal rings releasing antiviral drugs and lactic acid.Expert opinion: The vaginal microbiota (VM) is unique in that it is normally dominated by Lactobacillus species providing a degree of protection against infections; this however may vary, depending on the species and strains of Lactobacillus. Bacterial Vaginosis represents the most common dysbiosis of the VM and its prevalence can be influenced by use of contraception. Available evidence indicates that, under the influence of oral or systemically administered female sex hormones, there is apromotion of vaginal eubiosis, with aprevalence of ahealthy VM in which Lactobacilli predominate.

Effect of Oral versus Vaginal Administration of Estradiol and Dydrogesterone on the Proliferative and Secretory Transformation of Endometrium in Patients with Premature Ovarian Failure and Preparing for Assisted Reproductive Technology

Purpose

This study aimed to assess the efficacy of vaginally versus orally administered estradiol (E₂) and dydrogesterone (DG) on the proliferative and secretory transformation of endometrium in patients with premature ovarian failure (POF) and preparing for assisted reproductive technology.

Methods

Twenty patients with POF who were awaiting oocyte donation were included in the study; they were randomly assigned to two groups to receive E₂ and DG either orally or vaginally. Treatment efficacy was compared between the two groups regarding blood E₂ concentrations, endometrial thickness, histology using hematoxylin and eosin staining, immunohistochemical analysis of ER expression, and PR and pinopodes morphology using scanning electron microscopy.

Results

E₂ concentrations differed significantly between oral and vaginal E₂ and DG administration for 14 days (82.3 vs 1015.6 pg/mL; P < 0.001) and 21 days (85.0 vs 809.8 pg/mL; P < 0.001). Endometrial thickening was more pronounced in the vaginal treatment group, and also ER staining was stronger on days 14 and 21 in the vaginal treatment group. PR staining in the endometrium appeared more intense in the oral treatment group, which was, however, not significant. The abundance of developing pinopodes was higher in the vaginal treatment group (P = 0.04).

Conclusion

Vaginal administration of E₂ and DG is more effective than oral administration regarding proliferative and secretory transformation of the endometrium in POF patients and preparing for assisted reproductive technology.