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

A "three-in-one" thermosensitive gel system that enhances mucus and biofilm penetration for the treatment of vulvovaginal candidiasis

The special physiological barriers of women, such as vaginal mucus and self-cleaning behavior, pose great challenges for the treatment of vulvovaginal candidiasis (VVC), and the drug resistance caused by fungal biofilms limits the application of existing antifungal drugs. Based on this, we designed a "three-in-one" thermosensitive gel system (AF/BP Gel) loaded with antibiofilm nanoparticles (AF NPs) and mucus penetration-assisting nanoparticles (BP NPs) to achieve vaginal adhesion while enhancing mucus and biofilm penetration. AF NPs were loaded with farnesol (FAR) and amphotericin B (AMB), and FAR is one of quorum sensing molecules which can interfere with biofilm-related genes such as ALS3, HWP1, RAS1, CPH1, EFG1, NRG1, TUP1, UME6, and disperse mature biofilm, thus playing a synergic antibiofilm role with AMB. BP NPs was loaded with bromelain (BRO), which cleared the mucus barrier for AF NPs and help it penetrate deep into the infection. These two kinds of nanoparticles use the thermosensitive gel matrix to reach the surface of the vaginal mucosa uniformly and persistently to overcome the obstacle of vaginal self-cleaning. AF/BP Gel showed great anti-candida albicans activity in vitro and in vivo, and greatly improved the inflammatory conditions in VVC mice. Overall, this "three-in-one" thermosensitive gel system can overcome multiple physiological barriers and resist different periods of biofilm, providing a new platform for treating vagina-associated infections.

Advances in soft nanoparticle-based platforms for human and veterinary trichomoniasis therapy: A scoping review

This scoping review focuses on drug delivery systems based on soft materials designed for the administration of drugs with anti-Trichomonas vaginalis activity. It primarily examines their use in addressing human trichomoniasis, exploring their physicochemical characteristics, in vitro and in vivo evaluation and identifying existing challenges and gaps. Given the economic burden and the One Health approach, formulations developed aiming at treating animal infections - cattle and poultry - were also discussed. The review involved searching electronic databases, such as PubMed, Scopus, and Web of Science, to find studies published until May 2024; out of the 103 articles retrieved, 18 fulfilled the eligibility criteria. This study investigated soft-nanoparticle formulations, including polymericand lipid-based systems, and their incorporation into suitable formulations for topical application, including hydrogels and polymeric films. Additionally, the discussion covered toxicology and highlighted the knowledge gaps related to the potential use of these formulations in humans. Anti-trichomonas soft nano-based formulations emerge as promising candidates for treating gynecological and animal infections. In conclusion, further preclinical testing is necessary, as none of the formulations have progressed to human clinical trials and have only been evaluated in animal models.

The Application of Nano Drug Delivery Systems in Female Upper Genital Tract Disorders

The prevalence of female reproductive system disorders is increasing, especially among women of reproductive age, significantly impacting their quality of life and overall health. Managing these diseases effectively is challenging due to the complex nature of the female reproductive system, characterized by dynamic physiological environments and intricate anatomical structures. Innovative drug delivery approaches are necessary to facilitate the precise regulation and manipulation of biological tissues. Nanotechnology is increasingly considered to manage reproductive system disorders, for example, nanomaterial imaging allows for early detection and enhances diagnostic precision to determine disease severity and progression. Additionally, nano drug delivery systems are gaining attention for their ability to target the reproductive system successfully, thereby increasing therapeutic efficacy and decreasing side effects. This comprehensive review outlines the anatomy of the female upper genital tract by highlighting the complex mucosal barriers and their impact on systemic and local drug delivery. Advances in nano drug delivery are described for their sustainable therapeutic action and increased biocompatibility to highlight the potential of nano drug delivery strategies in managing female upper genital tract disorders.

Advance in Nanomedicine for Improving Mucosal Penetration and Effective Therapy of Cervical Cancer

Insufficient intratumor drug distribution and serious adverse effects are often associated with systemic chemotherapy for cervical cancer. Considering the location of cervical cancer, access to the cervix through the vagina may provide an alternative administration route for high drug amounts at the tumor site, minimal systemic exposure as well as convenience of non-invasive self-medication. Enormous progress has been made in nanomedicine to improve mucosal penetration and enhance the effectiveness of therapy for cervical cancer. This review article first introduce the physiological state of cervicovaginal cavity and the characteristics of intravaginal environment in cervical cancers. Based on introduction to the physiological state of cervicovaginal cavity and the characteristics of intravaginal environment in cervical cancers, both "first mucus-adhering then mucosal penetration" and "first mucus-penetrating then mucosal penetration" strategies are discussed with respect to mechanism, application condition, and examples. Finally, existing challenges and future directions are envisioned in the rational design, facile synthesis, and comprehensive utilization of nanomedicine for local therapy of cervical cancer. This review is expected to provide useful reference information for future research on nanomedicine for intravaginally administered formulations for topical treatment of cervical cancer.

Recent advances in in vitro models simulating the female genital tract toward more effective intravaginal therapeutic delivery

INTRODUCTION

Intravaginal drug delivery has emerged as a promising avenue for treating a spectrum of systemic and local female genital tract (FGT) conditions, using biomaterials as carriers or scaffolds for targeted and efficient administration. Much effort has been made to understand the natural barriers of this route and improve the delivery system to achieve an efficient therapeutic response.

AREAS COVERED

In this review, we conducted a comprehensive literature search using multiple databases (PubMed Scopus Web of Science Google Scholar), to discuss the potential of intravaginal therapeutic delivery, as well as the obstacles unique to this route. The in vitro cell models of the FGT and how they can be applied to probing intravaginal drug delivery are then analyzed. We further explore the limitations of the existing models and the possibilities to make them more promising for delivery studies or biomaterial validation. Complementary information is provided by in vitro acellular techniques that may shed light on mucus-drug interaction.

EXPERT OPINION

Advances in 3D models and cell cultures have enhanced our understanding of the FGT, but they still fail to replicate all variables. Future research should aim to use complementary methods, ensure stability, and develop consistent protocols to improve therapy evaluation and create better predictive in vitro models for women's health.

Biological Activity and Chemical Composition of Propolis Extracts with Potential Use in Vulvovaginal Candidiasis Management

Environmental sustainability is an increasing challenge in the pharmaceutical field, leading to the search for eco-friendly active ingredients. Among natural ingredients, propolis arises as an excellent alternative, being a complex substance with pharmacological properties. This work aims to explore the potential of propolis as a new pharmaceutical ingredient for the replacement of conventional vulvovaginal antifungals. Propolis extracts were obtained by Ultrasound-Assisted Extraction using different solvents (water, water/ethanol (50:50, v/v), and ethanol). Afterwards, the extracts were characterized regarding total phenolic content (TPC), antioxidant/antiradical activities, radical scavenging capacity, antifungal activity against strains of Candida species, and viability effect on two female genital cell lines. The aqueous extract achieved the best TPC result as well as the highest antioxidant/antiradical activities and ability to capture reactive oxygen species. A total of 38 phenolic compounds were identified and quantified by HPLC, among which ferulic acid, phloridzin and myricetin predominated. Regarding the anti-Candida spp. activity, the aqueous and the hydroalcoholic extracts achieved the best outcomes (with MIC values ranging between 128 and 512 μg/mL). The cell viability assays confirmed that the aqueous extract presented mild selectivity, while the hydroalcoholic and alcoholic extracts showed higher toxicities. These results attest that propolis has a deep potential for vulvovaginal candidiasis management, supporting its economic valorization.

Xanthan-carrageenan film containing sesame seed oil: A nanocomposite pharmaceutical platform for trichomoniasis treatment

Trichomoniasis is a common sexually transmitted infection that poses significant complications for women. Challenges in treatment include adverse effects and resistance to standard antimicrobial agents. Given this context, a sesame seed oil nanoemulsion (SONE) was developed and showed anti-Trichomonas vaginalis activity. To facilitate the local application of SONE, a polysaccharide film was developed using xanthan gum (XG) and κ-carrageenan gum (CG). A blend of XG and CG (at 2 %, ratio 1:3) plasticized with glycerol produced a more promising film (XCF) than using the gums individually. The film containing SONE (SONE-XCF) was successfully obtained by replacing the aqueous solvent with SONE via solvent evaporation technique. The hydrophilic SONE-XCF exhibited homogeneity and suitable mechanical properties for vaginal application. Furthermore, SONE-XCF demonstrated mucoadhesive properties and high absorption capacity for excessive vaginal fluids produced in vaginitis. It also had a disintegration time of over 8 h, indicating long retention at the intended site of action. Hemolysis and chorioallantoic membrane tests confirmed the safety of the film. Therefore, SONE-XCF is a biocompatible film with a natural composition and inherent activity against T. vaginalis, possessing exceptional characteristics that make it appropriate for vaginal application, offering an interesting alternative for trichomoniasis treatment.

Nanostrategy of Targeting at Embryonic Trophoblast Cells Using CuO Nanoparticles for Female Contraception

Effective contraceptives have been comprehensively adopted by women to prevent the negative consequences of unintended pregnancy for women, families, and societies. With great contributions of traditional hormonal drugs and intrauterine devices (IUDs) to effective female contraception by inhibiting ovulation and deactivating sperm, their long-standing side effects on hormonal homeostasis and reproductive organs for females remain concerns. Herein, we proposed a nanostrategy for female contraceptives, inducing embryonic trophoblast cell death using nanoparticles to prevent embryo implantation. Cupric oxide nanoparticles (CuO NPs) were adopted in this work to verify the feasibility of the nanostrategy and its contraceptive efficacy. We carried out the in vitro assessment on the interaction of CuO NPs with trophoblast cells using the HTR8/SVneo cell line. The results showed that the CuO NPs were able to be preferably uptaken into cells and induced cell damage via a variety of pathways including oxidative stress, mitochondrial damage, DNA damage, and cell cycle arrest to induce cell death of apoptosis, ferroptosis, and cuproptosis. Moreover, the key regulatory processes and the key genes for cell damage and cell death caused by CuO NPs were revealed by RNA-Seq. We also conducted in vivo experiments using a rat model to examine the contraceptive efficacy of both the bare CuO NPs and the CuO/thermosensitive hydrogel nanocomposite. The results demonstrated that the CuO NPs were highly effective for contraception. There was no sign of disrupting the homeostasis of copper and hormone, or causing inflammation and organ damage in vivo. In all, this nanostrategy exhibited huge potential for contraceptive development with high biosafety, efficacy, clinical translation, nonhormonal style, and on-demand for women.

mRNA nanodelivery systems: targeting strategies and administration routes

With the great success of coronavirus disease (COVID-19) messenger ribonucleic acid (mRNA) vaccines, mRNA therapeutics have gained significant momentum for the prevention and treatment of various refractory diseases. To function efficiently in vivo and overcome clinical limitations, mRNA demands safe and stable vectors and a reasonable administration route, bypassing multiple biological barriers and achieving organ-specific targeted delivery of mRNA. Nanoparticle (NP)-based delivery systems representing leading vector approaches ensure the successful intracellular delivery of mRNA to the target organ. In this review, chemical modifications of mRNA and various types of advanced mRNA NPs, including lipid NPs and polymers are summarized. The importance of passive targeting, especially endogenous targeting, and active targeting in mRNA nano-delivery is emphasized, and different cellular endocytic mechanisms are discussed. Most importantly, based on the above content and the physiological structure characteristics of various organs in vivo, the design strategies of mRNA NPs targeting different organs and cells are classified and discussed. Furthermore, the influence of administration routes on targeting design is highlighted. Finally, an outlook on the remaining challenges and future development toward mRNA targeted therapies and precision medicine is provided.

Three-Dimensionally Printed Vaginal Rings: Perceptions of Women and Gynecologists in a Cross-Sectional Survey

Three-dimensional printing technologies can be implemented for the fabrication of personalized vaginal rings (VRs) as an alternative approach to traditional manufacturing. Although several studies have demonstrated the potential of additive manufacturing, there is a lack of knowledge concerning the opinions of patients and clinicians. This study aimed to investigate the perception of women and gynecologists regarding VRs with personalized shapes. The devices were printed with different designs (traditional, "Y", "M", and flat circle) by Fused Deposition Modeling for a cross-sectional survey with 155 participants. Their anticipated opinion was assessed through a questionnaire after a visual/tactile analysis of the VRs. The findings revealed that most women would feel comfortable using some of the 3D-printed VR designs and demonstrated good acceptability for the traditional and two innovative designs. However, women presented multiple preferences when the actual geometry was assessed, which directly related to their age, previous use of the vaginal route, and perception of comfort. In turn, gynecologists favored prescribing traditional and flat circle designs. Overall, although there was a difference in the perception between women and gynecologists, they had a positive opinion of the 3D-printed VRs. Finally, the personalized VRs could lead to an increase in therapeutic adherence, by meeting women's preferences.

Encapsulation and release of hydrocortisone from proliposomes govern vaginal delivery

Topical preparations of hydrocortisone can be used for the anti-inflammatory treatment of the female genital area. Although the drug is a low-strength corticosteroid, systemic absorption and distribution of the drug are the most common safety risks associated with this therapy. In the current investigation, we elucidate the physicochemical properties of lipid-based drug carrier systems that govern the local bioavailability of hydrocortisone for intravaginal administration. For this purpose, we compared various proliposome formulations with a commercial cream. Depending on the availability of physiological acceptors, encapsulation and drug release from the lipid phase were found to be the most important drivers of drug bioavailability. The high permeability of hydrocortisone leads to rapid transport of the drug across the mucosal cell layer as indicated by experiments using HEC-1-A and CaSki cell monolayer models. Under sink conditions, differences in the release from the liposomes as determined in the Dispersion Releaser were almost negligible. However, under non-sink conditions, the drug release plateaued at levels corresponding to the encapsulation efficiency. After redispersion, all liposomal formulations performed better than the commercial drug product indicating that the encapsulation into the lipid phase is the main driver sustaining the release.

Contributions of nanotechnology to the intraductal drug delivery for local treatment and prevention of breast cancer

Breast cancer is a major public health problem, affecting millions of people. It is a very heterogeneous disease, with localized and invasive forms, and treatment generally consists of a combination of surgery and radiotherapy followed by administration of estrogen receptor modulators or aromatase inhibitors. Given its heterogeneity, management strategies that take into consideration the type of disease and biological markers and can provide more personalized and local treatment are required. More recently, the intraductal administration (i.e., into the breast ducts) of drugs has attracted significant attention due to its ability of providing drug distribution through the ductal tree in a minimally invasive manner. Although promising, intraductal administration is not trivial, and difficulties in duct identification and cannulation are important challenges to the further development of this route. New drug delivery strategies such as nanostructured systems can help to achieve the full benefits of the route due to the possibility of prolonging tissue retention, improving targeting and selectivity, increasing cytotoxicity and reducing the frequency of administration. This review aims at discussing the potential benefits and challenges of intraductal administration, focusing on the design and use of nanocarriers as innovative and feasible strategies for local breast cancer therapy and prevention.

Electrospinning Living Bacteria: A Review of Applications from Agriculture to Health Care

Living bacteria are used in biotechnologies that lead to improvements in health care, agriculture, and energy. Encapsulating bacteria into flexible and modular electrospun polymer fabrics that maintain their viability will further enable their use. This review will first provide a brief overview of electrospinning before examining the impact of electrospinning parameters, such as precursor composition, applied voltage, and environment on the viability of encapsulated bacteria. Currently, the use of nanofiber scaffolds to deliver live probiotics into the gut is the most researched application space; however, several additional applications, including skin probiotics (wound bandages) and menstruation products have also been explored and will be discussed. The use of bacteria-loaded nanofibers as seed coatings that promote plant growth, for the remediation of contaminated wastewaters, and in energy-generating microbial fuel cells are also covered in this review. In summary, electrospinning is an effective method for encapsulating living microorganisms into dry polymer nanofibers. While these living composite scaffolds hold potential for use across many applications, before their use in commercial products can be realized, numerous challenges and further investigations remain.

A systematic review of mucoadhesive vaginal tablet testing

Drug administration through the vaginal tract is one of the oldest modalities of pharmacotherapy, and it is also one of the most explored. Since the vaginal cavity has a wide surface area, a plentiful blood supply, and a complex network of blood arteries, it can evade hepatic first-pass metabolism and obtain high local drug concentrations. Vaginal pills look to be a good dose form since they are simple to use, portable, and can easily deliver the required amount of medicine. Vaginal formulations, on the other hand, are vulnerable to rapid expulsion due to the vaginal tract’s self-cleaning action, which reduces the formulation’s efficiency. Currently, there is an increasing amount of focus on mucoadhesive vaginal formulation research and development to fix the formulation at the place where the medicine can be released and/or absorbed. This article examines all of the strategies used by researchers to develop a mucoadhesive vaginal tablet that is safe, effective, and comfortable for the user.

Long-acting HIV Pre-exposure Prophylaxis (PrEP) approaches: Recent advances, emerging technologies and development challenges

Introduction:

Poor or inconsistent adherence to daily oral pre-exposure prophylaxis (PrEP) has emerged as a key barrier to effective HIV prevention. The advent of potent long-acting (LA) antiretrovirals (ARVs) in conjunction with advances in controlled release technologies has enabled LA ARV drug delivery systems (DDS) capable of providing extended dosing intervals and overcome the challenge of suboptimal drug adherence with daily oral dosing.

Areas covered:

This review discusses the current state of the LA PrEP field, recent advances, and emerging technologies, including ARV prodrug modifications and new DDS. Technological challenges, knowledge gaps, preclinical testing considerations, and future directions important in the context of clinical translation and implementation of LA HIV PrEP are discussed.

Expert opinion:

The HIV prevention field is evolving faster than ever and the bar for developing next-generation LA HIV prevention options continues to rise. The requirements for viable LA PrEP products to be implemented in resource-limited settings are challenging, necessitating proactive consideration and product modifications during the design and testing of promising new candidates. If successfully translated, next-generation LA PrEP that are safe, affordable, highly effective, and accepted by both end-users and key stakeholders will offer significant potential to curb the HIV pandemic.

Chitosan-poly(ethylene oxide) nanofibrous mat as a vaginal platform for tenofovir disoproxyl fumarate - The effect of vaginal pH on drug carrier performance

In the present work, a solution blow spun nanofibrous mat comprised of chitosan (CS) and poly(ethylene oxide) (PEO) was obtained as vaginal platform for tenofovir disoproxil fumarate (TDF) to prevent sexually transmitted infections. Apart from physicochemical and mechanical analysis, the specific steps involved studies on nanofibrous mat mucoadhesive and swelling characteristics upon pH fluctuations over the physiological range. Physicochemical analysis showed uniform drug distribution within the CS/PEO mat volume and pointed toward physical interactions between the drug and polymers. TDF-loaded CS/PEO nanofibrous mat was shown potentially safe when evaluated by the MTT metabolic activity and JC-1 assays in human vaginal epithelial cells VK2-E6/E7. In vitro antiviral studies indicated inhibition efficacy of TDF-CS/PEO nanofibrous mat toward HSV-2 virus and proved the SBS process does not change the microbicidal activity of drug molecule. Fluctuations in the physiological vaginal pH range of 3.8 to 5.0 substantially affected mucoadhesive and swelling behavior of chitosan which in turn impacted drug dissolution rate from polymer carrier. The rate of permeation and accumulation of TDF in vaginal tissue differed in response to vaginal pH. Faster drug permeation assessed at pH 5.0 suggests that an increase in vaginal pH could improve TDF bioavailability at earlier time points.

Dexamethasone Increases the Anesthetic Success in Patients with Symptomatic Irreversible Pulpitis: A Meta-Analysis

Inferior alveolar nerve block (IANB) has a high failure rate in subjects with symptomatic irreversible pulpitis (SIP). It has been suggested that drugs with anti-inflammatory activity could improve the efficacy of the anesthetic used for IANB. The aim of this study was to assess the effect of dexamethasone on the success of dental anesthesia in patients with SIP. An information search was performed using PubMed and Google Scholar. The risk of bias of the included studies was evaluated with the Cochrane Collaboration’s risk-of-bias tool. The anesthetic success rate, pain intensity (VAS), and adverse effects were extracted. Data were analyzed using the Mantel−Haenszel test and odds ratio or the inverse variance and standardized mean difference. Dexamethasone increased the anesthetic success in comparison with placebo (n = 502; p < 0.001; OR = 2.59; 95% CIs: 1.46 to 4.59). Moreover, patients who were given dexamethasone had lower pain scores at 6 h (n = 302; p < 0.001; MD= −1.43; 95% CIs: −2.28 to −0.58), 12 h (n = 302; p < 0.0001; MD = −1.65; 95% CIs: −2.39 to −0.92), and 24 h (n = 302; p < 0.0008; MD = −1.27; 95% CIs: −2.01 to −0.53) when compared with placebo. In conclusion, the systemic administration of dexamethasone increases the anesthetic success rate and improves pain management in patients with SIP.

Pharmacokinetics of Vaginal vs Buccal Misoprostol for Labor Induction at Term

The IMPROVE study (NCT02408315) compared the efficacy and safety of vaginal and buccal administration of misoprostol for full‐term, uncomplicated labor induction. This report compares the pharmacokinetics of misoprostol between vaginal and buccal routes. Women greater than or equal to 14 years of age undergoing induction of labor greater than or equal to 37 weeks gestation without significant complications were randomized to vaginal or buccal misoprostol 25 μg followed by 50 μg doses every 4 h. Misoprostol acid concentrations were determined using liquid chromatography‐tandem mass spectrometry for the first 8 h in a subgroup of participants. A population pharmacokinetic model was developed using NONMEM. Plasma concentrations (n = 469) from 47 women were fit to a one‐compartment nonlinear clearance model. The absorption rate constant (k_a) was dependent on both route and dose of administration: buccal 25 μg 0.724 (95% confidence interval, 0.54–0.92) h⁻¹; 50 μg 0.531 (0.37–0.63) h⁻¹; vaginal 25 μg 0.507 (0. 2–1. 4) h⁻¹; and 50 μg 0.246 (0.103–0.453) h⁻¹. Relative bioavailability for vaginal compared to buccal route was 2.4 (1.63–4.77). There was no effect of body mass index or age on apparent clearance 705 (431–1099) L/h or apparent volume of distribution 632 (343–1008) L. The area under the concentration–time curve to 4 h following the first 25 μg dose of misoprostol was 16.5 (15.4–17.5) pg h/ml for buccal and 34.3 (32.5–36.1) pg h/ml for vaginal administration. The rate of buccal absorption was two times faster than that of vaginal, whereas bioavailability of vaginal administration was 2.4 times higher than that of buccal. Decreased time to delivery observed with vaginal dosing may be due to higher exposure to misoprostol acid compared to buccal.

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.