Vaginal film drug delivery of the pyrimidinedione IQP-0528 for the prevention of HIV infection

Exploiting Polymeric Films as a Multipurpose Drug Delivery System: a Review

Polymeric films are drug delivery systems that maintain contact with the delivery tissue and sustain a controlled release of therapeutic molecules. These systems allow a longer time of drug contact with the target site in the case of topical treatments and allow the controlled administration of drugs. They can be manufactured by various methods such as solvent casting, hot melt extrusion, electrospinning, and 3D bioprinting. Furthermore, they can employ various polymers, for example PVP, PVA, cellulose derivatives, chitosan, gelling gum, pectin, and alginate. Its versatility is also applicable to different routes of administration, as it can be administered to the skin, oral mucosa, vaginal canal, and eyeballs. All these factors allow numerous combinations to obtain a better treatment. This review focuses on exploring some possible ways to develop them and some particularities and advantages/disadvantages in each case. It also aims to show the versatility of these systems and the advantages and disadvantages in each case, as they bring the opportunity to develop different medicines to facilitate therapies for the most diverse purposes .

Development and Evaluation of Nanoparticles-in-Film Technology to Achieve Extended In Vivo Exposure of MK-2048 for HIV Prevention

MK-2048 is a second-generation integrase inhibitor active against HIV, which has been applied vaginally using ring formulations. In this work, a nanoparticle-in-film technology was developed as a discrete pre-exposure prophylactic product option against HIV for an extended duration of use. A film platform loaded with poly (lactic-co-glycolic acid) nanoparticles (PNP) encapsulating MK-2048 was engineered. MK-2048 PNPs were loaded into films that were manufactured via the solvent casting method. Physicochemical and mechanical properties, in vitro efficacy, Lactobacillus compatibility, in vitro and ex vivo permeability, and in vivo pharmacokinetics in macaques were evaluated. PNPs with a mean diameter of 382.2 nm and −15.2 mV zeta potential were obtained with 95.2% drug encapsulation efficiency. PNP films showed comparable in vitro efficacy to free MK-2048 (IC50 0.46 vs. 0.54 nM) and were found to have no impact on Lactobacillus. MK-2048 encapsulated in PNPs showed an increase in permeability (>4-fold) compared to the free MK-2048 in MDCKII cell lines. Furthermore, PNPs had higher ectocervical tissue permeability (1.7-fold) compared to free MK-2048. PNP films showed sustained drug levels for at least 3 weeks in the macaque vaginal fluid. This work demonstrates the synergy of integrating nanomedicine and polymeric film technology to achieve sustained vaginal drug delivery.

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.

Hexavalent sperm-binding IgG antibody released from vaginal film for development of potent on-demand nonhormonal female contraception

Nearly half of all pregnancies in the United States are unintended due to millions of women avoiding available hormonal contraceptive methods as a result of real and/or perceived side effects associated with the use of exogenous hormones. Topical vaginal delivery of antisperm monoclonal antibodies that could agglutinate sperm into clusters too large to penetrate mucus and prevent sperm from reaching the egg represents a potentially safe and potent mechanism for nonhormonal contraception. We report here the engineering of a vaginal film loaded with hexavalent (i.e., 6 Fab) antisperm IgG, made using GMP manufacturing processes, that possesses significantly superior agglutination potency than the parent IgG, enabling potent on-demand nonhormonal contraception via effectively agglutinating all human sperm within minutes.

Nonhormonal products for on-demand contraception are a global health technology gap; this unmet need motivated us to pursue the use of sperm-binding monoclonal antibodies to enable effective on-demand contraception. Here, using the cGMP-compliant Nicotiana-expression system, we produced an ultrapotent sperm-binding IgG antibody possessing 6 Fab arms per molecule that bind a well-established contraceptive antigen target, CD52g. We term this hexavalent antibody “Fab-IgG-Fab” (FIF). The Nicotiana-produced FIF had at least 10-fold greater sperm-agglutination potency and kinetics than the parent IgG, while preserving Fc-mediated trapping of individual spermatozoa in mucus. We formulated the Nicotiana-produced FIF into a polyvinyl alcohol–based water-soluble contraceptive film and evaluated its potency in reducing progressively motile sperm in the sheep vagina. Two minutes after vaginal instillation of human semen, no progressively motile sperm were recovered from the vaginas of sheep receiving FIF Film. Our work supports the potential of multivalent contraceptive antibodies to provide safe, effective, on-demand nonhormonal contraception.

A Fast and Convenient Synthesis of New Water-Soluble, Polyanionic Dendrimers

Reasonably simple, efficient, and possessing aspects of generality, the methodology for the synthesis of new, water-soluble, dendrimeric polyesters with great potential applications as antiviral drugs in their own right is described. The essential aspect of the presented approach is a quite unique, immediate access to the polyanionic material at each generation during divergent synthesis. Six target polyanionic dendrimers (generations 1, 2, and 3) have been synthesized. The key monomers applied in this project were 1,3,5-benzenetricarboxylic acid derivatives, which also worked as direct precursors of the charged dendrimer surface.

Recent Advances in Polymer-Based Vaginal Drug Delivery Systems

The vagina has been considered a potential drug administration route for centuries. Most of the currently marketed and investigated vaginal formulations are composed with the use of natural or synthetic polymers having different functions in the product. The vaginal route is usually investigated as an administration site for topically acting active ingredients; however, the anatomical and physiological features of the vagina make it suitable also for drug systemic absorption. In this review, the most important natural and synthetic polymers used in vaginal products are summarized and described, with special attention paid to the properties important in terms of vaginal application. Moreover, the current knowledge on the commonly applied and innovative dosage forms designed for vaginal administration was presented. The aim of this work was to highlight the most recent research directions and indicate challenges related to vaginal drug administrations. As revealed in the literature overview, intravaginal products still gain enormous scientific attention, and novel polymers and formulations are still explored. However, there are research areas that require more extensive studies in order to provide the safety of novel vaginal products.

Efavirenz nanomicelles loaded vaginal film (EZ film) for preexposure prophylaxis (PrEP) of HIV

Preexposure prophylaxis (PrEP) using oral or vaginal microbicide is an emerging and effective strategy to prevent HIV transmission. Vaginal film is becoming more acceptable and a convenient dosage form compared to cream, gel and suppository. Extremely poor aqueous solubility of efavirenz (EFV) limits its use as vaginal microbicide. The aim of this study was to develop and evaluate a monomeric surfactant free, rapidly soluble vaginal film of EFV (EZ film). EZ film was prepared using a tetrafunctional block polymer (Tetronic 1107), carrageenan and polyvinyl alcohol (PVA) by solvent evaporation method. First, different solubilizers were screened for EFV solubility, in vitro cytotoxicity and cell membrane integrity assay on HeLa cells. Optimized film was characterized for solid state, mechanical strength, epithelial integrity, in vitro drug release in simulated vaginal fluid (SVF), simulated seminal fluid (SSF) and in vitro anti-HIV activity. Optimized EZ film showed a particle size of 48 ± 3.8 nm with PDI of 0.299. Differential scanning colorimetry (DSC) thermogram suggested the complete amorphization of EFV within the film. EZ film rapidly disintegrated (30 s) with complete release of EFV in SVF and SSF. The film was found to be non-toxic to HeLa cells and showed similar anti-HIV-1 activity as that of EFV in DMSO. EZ film did not show any significant change in the TEER value in HEC 1A cell line. Hence, the findings from the current study strongly suggest that the EZ film could be a cost-effective and convenient dosage form for PrEP of HIV.

Development of mucoadhesive vaginal films based on HPMC and zein as novel formulations to prevent sexual transmission of HIV

Although vaginal films were initially developed for a fast release of the drug, with the adequate formulation they can also be useful for sustained release. The latest strategies for the prevention of the sexual transmission of HIV have moved towards sustained-release dosage forms, so films may be an effective strategy that could also improve the patient's comfort. A hydrophilic polymer (hydroxypropylmethyl cellulose) and an amphiphilic polymer (zein) have been evaluated for the development of Tenofovir sustained-release vaginal films. The modification of the film's properties by the inclusion of polar (glycerol and polyethylene glycol 400 (PEG)) and amphiphilic (tributyl citrate and oleic acid) plasticisers was also evaluated. The films' physicochemical and mechanical properties were determined. The in vitro release of Tenofovir from the films and their bioadhesive capacity and behaviour in simulated vaginal fluid were also assessed. The combination of hydroxypropylmethyl cellulose and zein in films (ratio 1:5), with the inclusion of PEG (40% w/w) proved not only to have excellent mechanical properties, but was also able to release TFV in a sustained manner for 120 h and remain attached to biological tissues throughout this time. This film could be an interesting option for the prevention of sexual transmission of HIV.

A Quantitative Disintegration Method for Polymeric Films

PURPOSE

Current in vitro disintegration methods for polymeric films are qualitative and introduce significant user bias. The goal of these studies is to develop a novel, quantitative disintegration technique which can be used to characterize polymeric films in vitro.

METHODS

A method was developed using a Texture Analyzer instrument to evaluate film disintegration. Solvent casted, clinically advanced, anti-HIV, vaginal films as well as marketed vaginal films were used throughout these studies. Method development followed a Quality by Design (QbD) process and was used to evaluate film products.

RESULTS

The current method developed provided reproducible, quantitative disintegration times for the commercially available Vaginal Contraceptive Film (57.88 ± 5.98 sec.). It distinguished between two clinically advanced antiretroviral containing films based on disintegration time (p value < 0.001); the tenofovir film (41.28 ± 3.35 sec.) and the dapivirine film (88.36 ± 10.61 sec.). This method could also distinguish between tenofovir and dapivirine films which had been altered in terms of volume (p<0.0001) and formulation (p<0.0001) based on disintegration time.

CONCLUSIONS

This method can be applied for pharmaceutical films for ranging indications as part of vigorous in vitro characterization. Parameters of the test can be altered based on site of application or indication.

User input in iterative design for prevention product development: leveraging interdisciplinary methods to optimize effectiveness

The development of HIV-preventive topical vaginal microbicides has been challenged by a lack of sufficient adherence in later stage clinical trials to confidently evaluate effectiveness. This dilemma has highlighted the need to integrate translational research earlier in the drug development process, essentially applying behavioral science to facilitate the advances of basic science with respect to the uptake and use of biomedical prevention technologies. In the last several years, there has been an increasing recognition that the user experience, specifically the sensory experience, as well as the role of meaning-making elicited by those sensations, may play a more substantive role than previously thought. Importantly, the role of the user-their sensory perceptions, their judgements of those experiences, and their willingness to use a product-is critical in product uptake and consistent use post-marketing, ultimately realizing gains in global public health. Specifically, a successful prevention product requires an efficacious drug, an efficient drug delivery system, and an effective user. We present an integrated iterative drug development and user experience evaluation method to illustrate how user-centered formulation design can be iterated from the early stages of preclinical development to leverage the user experience. Integrating the user and their product experiences into the formulation design process may help optimize both the efficiency of drug delivery and the effectiveness of the user.

Carrageenan based hydrogels for drug delivery, tissue engineering and wound healing

Carrageenan is a class of naturally occurring sulphated polysaccharides, which is currently a promising candidate in tissue engineering and regenerative medicine as it resemblances native glycosaminoglycans. From pharmaceutical drug formulations to tissue engineered scaffolds, carrageenan has broad range of applications. Here we provide an overview of developing various forms of carrageenan based hydrogels. We focus on how these fabrication processes has an effect on physiochemical properties of the hydrogel. We outline the application of these hydrogels not only pertaining to sustained drug release but also their application in bone and cartilage tissue engineering as well as in wound healing and antimicrobial formulations. Administration of these hydrogels through various routes for drug delivery applications has been critically reviewed. Finally, we conclude by summarizing the current and future outlook that promotes the seaweed-derived polysaccharide as versatile, promising biomaterial for a variety of bioengineering applications.

Designing and developing suppository formulations for anti-HIV drug delivery

Despite a long history of use for rectal and vaginal drug delivery, the current worldwide market for suppositories is limited primarily due to a lack of user acceptability. Therefore, virtually no rational pharmaceutical development of antiviral suppositories has been performed. However, suppositories offer several advantages over other antiviral dosage forms. Current suppository designs have integrated active pharmaceutical ingredients into existing formulation designs without optimization. As such, emerging suppository development has been focused on improving upon the existing classical design to enhance drug delivery and is poised to open suppository drug delivery to a broader range of drugs, including antiretroviral products. Thus, with continuing research into rational suppository design and development, there is significant potential for antiretroviral suppository drug delivery.

Nanoparticle Encapsulation for Antiretroviral Pre-Exposure Prophylaxis

HIV continues to be one of the greatest challenges facing the global health community. More than 36 million people currently live with HIV and, in 2015 2.1 million new infections were reported globally. Pre-Exposure Prophylaxis (PrEP) prevents HIV infection by inhibiting viral entry, replication, or integration at the primary site of pathogenic contraction. Failures of large antiretroviral drug (ARV) PrEP clinical trials indicate the current insufficiencies of PrEP for women in high-risk areas, such as sub-Saharan Africa. A combination of social, adherence, and drug barriers create these insufficiencies and limit the efficacy of ARV. Nanotechnology offers the promise of extended drug release and enhances bioavailability of ARVs when encapsulated in polymeric nano-particles. Nanoparticle encapsulation has been evaluated in vitro in comparative studies to drug solutions and exhibit higher efficacy and lower cytotoxicity profiles. Delivery systems for nanoparticle PrEP facilitate administration of nano-encapsulated ARVs to high-risk tissues. In this mini-review, we summarize the comparative nanoparticle and drug solution studies and the potential of two delivery methods: thermosensitive gels and polymeric nanoparticle films for direct prophylactic applications.

A Dose Ranging Pharmacokinetic Evaluation of IQP-0528 Released from Intravaginal Rings in Non-Human Primates

PURPOSE

Design of intravaginal rings (IVRs) for delivery of antiretrovirals is often guided by in vitro release under sink conditions, based on the assumption that in vivo release will follow a similar release profile.

METHODS

We conducted a dose-ranging study in the female reproductive tract of pigtail macaques using matrix IVRs containing IQP-0528, a poorly soluble but highly potent antiretroviral drug with an IC₉₀ of 146 ng/mL. These IVRs consisted of drug-loaded segments, 15.6% IQP-0528 in Tecoflex 85A, comprising either all, half, or a quarter of the entire ring.

RESULTS

In vitro release under sink conditions demonstrates loading-proportional release, with a cumulative 30-day release of 48.5 ± 2.2 mg for our 100% loaded ring, 24.8 ± .36 mg from our 50% loaded ring, and 13.99 ± 1.58 mg from our 25% loaded ring. In vivo, while drug concentration in vaginal fluid is well in excess of IQP-0528's EC₉₀, we find no statistical difference between the different ring loadings in either swab drug levels or drug released from our rings.

CONCLUSIONS

We show that in vitro release may not accurately reflect in vivo release, particularly for poorly soluble drugs. All tested loadings of our IVRs are capable of delivering IQP-0528 well in excess of the IC₉₀.

Vaginal film for prevention of HIV: using visual and tactile evaluations among potential users to inform product design

Topical prevention of HIV and other STIs is a global health priority. To provide options for users, developers have worked to design safe, effective and acceptable vaginal dissolving film formulations. We aimed to characterize user experiences of vaginal film size, texture and color, and their role in product-elicited sensory perceptions (i.e. perceptibility), acceptability and willingness to use. In the context of a user-centered product evaluation study, we elicited users' 'first impressions' of various vaginal film formulation designs via visual and tactile prototype inspection during a qualitative user evaluation interview. Twenty-four women evaluated prototypes. Participants considered size and texture to be important for easy insertion. Color was more important following dissolution than prior to insertion. When asked to combine and balance all properties to arrive at an ideal film, previously stated priorities for individual characteristics sometimes shifted, with the salience of some individual characteristics lessening when multiple characteristics were weighted in combination. While first impressions alone may not drive product uptake, users' willingness to initially try a product is likely impacted by such impressions. Developers should consider potential users' experiences and preferences in vaginal film design. This user-focused approach is useful for characterizing user sensory perceptions and experiences relevant to early design of prevention technologies.

Historical development of vaginal microbicides to prevent sexual transmission of HIV in women: from past failures to future hopes

Infection with human immunodeficiency virus (HIV) remains a global public health concern and is particularly serious in low- and middle-income countries. Widespread sexual violence and poverty, among other factors, increase the risk of infection in women, while currently available prevention methods are outside the control of most. This has driven the study of vaginal microbicides to prevent sexual transmission of HIV from men to women in recent decades. The first microbicides evaluated were formulated as gels for daily use and contained different substances such as surfactants, acidifiers and monoclonal antibodies, which failed to demonstrate efficacy in clinical trials. A gel containing the reverse transcriptase inhibitor tenofovir showed protective efficacy in women. However, the lack of adherence by patients led to the search for dosage forms capable of releasing the active principle for longer periods, and hence to the emergence of the vaginal ring loaded with dapivirine, which requires a monthly application and is able to reduce the sexual transmission of HIV. The future of vaginal microbicides will feature the use of alternative dosage forms, nanosystems for drug release and probiotics, which have emerged as potential microbicides but are still in the early stages of development. Protecting women with vaginal microbicide formulations would, therefore, be a valuable tool for avoiding sexual transmission of HIV.

Preformulation and Vaginal Film Formulation Development of Microbicide Drug Candidate CSIC for HIV prevention

PURPOSE

5-chloro-3-[phenylsulfonyl] indole-2-carboxamide (CSIC) is a highly potent non-nucleoside reverse transcriptase inhibitor (NNRTI) of HIV-1 which has been shown to have a more desirable resistance profile than other NNRTIs in development as HIV prevention strategies. This work involves generation of preformulation data for CSIC and systematic development of a cosolvent system to effectively solubilize this hydrophobic drug candidate. This system was then applied to produce a polymeric thin film solid dosage form for vaginal administration of CSIC for use in prevention of sexual acquisition of HIV.

METHODS

Extensive preformulation, formulation development, and film characterization studies were conducted. An HPLC method was developed for CSIC quantification. Preformulation tests included solubility, crystal properties, stability, and drug-excipient compatibility. Cytotoxicity was evaluated using both human epithelial and mouse macrophage cell lines. Ternary phase diagram methodology was used to identify a cosolvent system for CSIC solubility enhancement. Following preformulation evaluation, a CSIC film formulation was developed and manufactured using solvent casting technique. The developed film product was assessed for physicochemical properties, anti-HIV bioactivity, and Lactobacillus biocompatibility during 12-month stability testing period.

RESULTS

Preformulation studies showed CSIC to be very stable. Due to its hydrophobicity, a cosolvent system consisting of polyethylene glycol 400, propylene glycol, and glycerin (5:2:1, w/w/w) was developed, which provided a uniform dispersion of CSIC in the film formulation. The final film product met target specifications established for vaginal microbicide application.

CONCLUSIONS

The hydrophobic drug candidate CSIC was successfully formulated with high loading capacity in a vaginal film by means of a cosolvent system. The developed cosolvent strategy is applicable for incorporation of other hydrophobic drug candidates in the film platform.

Development and in vivo safety assessment of tenofovir-loaded nanoparticles-in-film as a novel vaginal microbicide delivery system

Topical pre-exposure prophylaxis (PrEP) with antiretroviral drugs holds promise in preventing vaginal transmission of HIV. However, significant biomedical and social issues found in multiple past clinical trials still need to be addressed in order to optimize protection and users' adherence. One approach may be the development of improved microbicide products. A novel delivery platform comprising drug-loaded nanoparticles (NPs) incorporated into a thin polymeric film base (NPs-in-film) was developed in order to allow the vaginal administration of the microbicide drug candidate tenofovir. The system was optimized for relevant physicochemical features and characterized for biological properties, namely cytotoxicity and safety in a mouse model. Tenofovir-loaded poly(lactic-co-glycolic acid) (PLGA)/stearylamine (SA) composite NPs with mean diameter of 127nm were obtained with drug association efficiency above 50%, and further incorporated into an approximately 115μm thick, hydroxypropyl methylcellulose/poly(vinyl alcohol)-based film. The system was shown to possess suitable mechanical properties for vaginal administration and to quickly disintegrate in approximately 9min upon contact with a simulated vaginal fluid (SVF). The original osmolarity and pH of SVF was not affected by the film. Tenofovir was also released in a biphasic fashion (around 30% of the drug in 15min, followed by sustained release up to 24h). The incorporation of NPs further improved the adhesive potential of the film to ex vivo pig vaginal mucosa. Cytotoxicity of NPs and film was significantly increased by the incorporation of SA, but remained at levels considered tolerable for vaginal delivery of tenofovir. Moreover, histological analysis of genital tissues and cytokine/chemokine levels in vaginal lavages upon 14days of daily vaginal administration to mice confirmed that tenofovir-loaded NPs-in-film was safe and did not induce any apparent histological changes or pro-inflammatory response. Overall, obtained data support that the proposed delivery system combining the use of polymeric NPs and a film base may constitute an exciting alternative for the vaginal administration of microbicide drugs in the context of topical PrEP.

STATEMENT OF SIGNIFICANCE

The development of nanotechnology-based microbicides is a recent but promising research field seeking for new strategies to circumvent HIV sexual transmission. Different reports detail on the multiple potential advantages of using drug nanocarriers for such purpose. However, one important issue being frequently neglected regards the development of vehicles for the administration of microbicide nanosystems. In this study, we propose and detail on the development of a nanoparticle-in-film system for the vaginal delivery of the microbicide drug candidate tenofovir. This is an innovative approach that, to our best knowledge, had never been tested for tenofovir. Results, including those from in vivo testing, sustain that the proposed system is safe and holds potential for further development as a vaginal microbicide product.

Safety and Pharmacokinetics of Quick-Dissolving Polymeric Vaginal Films Delivering the Antiretroviral IQP-0528 for Preexposure Prophylaxis

For human immunodeficiency virus (HIV) prevention, microbicides or drugs delivered as quick-dissolving films may be more acceptable to women than gels because of their compact size, minimal waste, lack of an applicator, and easier storage and transport. This has the potential to improve adherence to promising products for preexposure prophylaxis. Vaginal films containing IQP-0528, a nonnucleoside reverse transcriptase inhibitor, were evaluated for their pharmacokinetics in pigtailed macaques. Polymeric films (22 by 44 by 0.1 mm; providing 75% of a human dose) containing IQP-0528 (1.5%, wt/wt) with and without poly(lactic-co-glycolic acid) (PLGA) nanoparticle encapsulation were inserted vaginally into pigtailed macaques in a crossover study design (n = 6). With unencapsulated drug, the median (range) vaginal fluid concentrations of IQP-0528 were 160.97 (2.73 to 2,104), 181.79 (1.86 to 15,800), and 484.50 (8.26 to 4,045) μg/ml at 1, 4, and 24 h after film application, respectively. Median vaginal tissue IQP-0528 concentrations at 24 h were 3.10 (0.03 to 222.58) μg/g. The values were similar at locations proximal, medial, and distal to the cervix. The IQP-0528 nanoparticle-formulated films delivered IQP-0528 in vaginal tissue and secretions at levels similar to those obtained with the unencapsulated formulation. A single application of either formulation did not disturb the vaginal microflora or the pH (7.24 ± 0.84 [mean ± standard deviation]). The high mucosal IQP-0528 levels delivered by both vaginal film formulations were between 1 and 5 log higher than the in vitro 90% inhibitory concentration (IC90) of 0.146 μg/ml. The excellent coverage and high mucosal levels of IQP-0528, well above the IC90, suggest that the films may be protective and warrant further evaluation in a vaginal repeated low dose simian-human immunodeficiency virus (SHIV) transmission study in macaques and clinically in women.

Formulation, development and characterization of mucoadhesive film for treatment of vaginal candidiasis

Objective:

The objective of the present investigation was formulation, optimization and characterization of mucoadhesive film of clotrimazole (CT) which is patient-convenient and provides an effective alternative for the treatment of vaginal candidiasis. CT is an antimycotic drug applied locally for the treatment of vaginal candidiasis.

Materials and Methods:

Mucoadhesive vaginal films were prepared by solvent casting technique using hydroxyl propylcellulose and sodium alginate as polymers. Propylene glycol and polyethylene glycol-400 were evaluated as plasticizers. The mucoadhesive vaginal films were evaluated for percentage elongation, tensile strength, folding endurance, drug content, in vitro disintegration time, in vitro dissolution study, swelling index, bioadhesive strength, and diffusion study.

Results:

Among various permeation enhancers used, isopropyl myristate was found to be suitable. To evaluate the role of the concentration of permeation enhancer and concentration of polymers in the optimization of mucoadhesive vaginal film, 3² full factorial design was employed. Optimized batch showed in vitro disintegration time, 18 min; drug content, 99.83%; and tensile strength, 502.1 g/mm². In vitro diffusion study showed that 77% drug diffusion occurred in 6 h. This batch was further evaluated by scanning electron microscopy indicating uniformity of the film. In vitroLactobacillus inhibition and in vitro antifungal activity of optimized batch showed an inhibitory effect against Candida albicans and no effect on Lactobacillus, which is a normal component of vaginal flora.

Conclusion:

Mucoadhesive vaginal film of CT is an effective dosage form for the treatment of vaginal candidiasis.

Recent advances on anti-HIV vaginal delivery systems development

A review of the recent outcomes regarding technologies to prevent vaginal transmission of HIV, mainly by using antiretroviral (ARV) drugs formulated as microbicides. An introduction about the HIV transmission mechanisms by the vaginal route is included, together with the recent challenges faced for development of successful microbicide products. The outcomes of clinical evaluations are mentioned, and the different formulation strategies studied to-date, with the requirements, advantages, disadvantages and limitations of each dosage-form type, are presented. Finally, the recent attempts to apply various types of nanotechnologies in order to develop advanced microbicide-products and overcome existing limitations, are discussed.

Double Variational Binding--(SMILES) Conformational Analysis by Docking Mechanisms for Anti-HIV Pyrimidine Ligands

Variational quantitative binding–conformational analysis for a series of anti-HIV pyrimidine-based ligands is advanced at the individual molecular level. This was achieved by employing ligand-receptor docking algorithms for each molecule in the 1,3-disubstituted uracil derivative series that was studied. Such computational algorithms were employed for analyzing both genuine molecular cases and their simplified molecular input line entry system (SMILES) transformations, which were created via the controlled breaking of chemical bonds, so as to generate the longest SMILES molecular chain (LoSMoC) and Branching SMILES (BraS) conformations. The study identified the most active anti-HIV molecules, and analyzed their special and relevant bonding fragments (chemical alerts), and the recorded energetic and geometric docking results (i.e., binding and affinity energies, and the surface area and volume of bonding, respectively). Clear computational evidence was also produced concerning the ligand-receptor pocket binding efficacies of the LoSMoc and BraS conformation types, thus confirming their earlier presence (as suggested by variational quantitative structure-activity relationship, variational-QSAR) as active intermediates for the molecule-to-cell transduction process.

An Intravaginal Ring for the Simultaneous Delivery of an HIV-1 Maturation Inhibitor and Reverse-Transcriptase Inhibitor for Prophylaxis of HIV Transmission

Nucleocapsid 7 (NCp7) inhibitors have been investigated extensively for their role in impeding the function of HIV-1 replication machinery and their ability to directly inactivate the virus. A class of NCp7 zinc finger inhibitors, S-acyl-2-mercaptobenzamide thioesters (SAMTs), was investigated for topical drug delivery. SAMTs are inherently unstable because of their hydrolytically labile thioester bond, thus requiring formulation approaches that can lend stability. We describe the delivery of N-[2-(3,4,5-trimethoxybenzoylthio)benzoyl]-β-alaninamide (SAMT-10), as a single agent antiretroviral (ARV) therapeutic and in combination with the HIV-1 reverse-transcriptase inhibitor pyrimidinedione IQP-0528, from a hydrophobic polyether urethane (PEU) intravaginal ring (IVR) for a month. The physicochemical stability of the ARV-loaded IVRs was confirmed after 3 months at 40°C/75% relative humidity. In vitro, 25 ± 3 mg/IVR of SAMT-10 and 86 ± 13 mg/IVR of IQP-0528 were released. No degradation of the hydrolytically labile SAMT-10 was observed within the matrix. The combination of ARVs had synergistic antiviral activity when tested in in vitro cell-based assays. Toxicological evaluations performed on an organotypic EpiVaginal(™) tissue model demonstrated a lack of formulation toxicity. Overall, SAMT-10 and IQP-0528 were formulated in a stable PEU IVR for sustained release. Our findings support the need for further preclinical evaluation. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:3426-3439, 2015.

Biodegradable Film for the Targeted Delivery of siRNA-Loaded Nanoparticles to Vaginal Immune Cells

The goal of this study was to develop and characterize a novel intravaginal film platform for targeted delivery of small interfering RNA (siRNA)-loaded nanoparticles (NP) to dendritic cells as a potential gene therapy for the prevention of sexually transmitted human immunodeficiency virus (HIV) infection. Poly(ethylene glycol) (PEG)-functionalized poly(D, L-lactic-co-glycolic acid) (PLGA)/polyethylenimine (PEI)/siRNA NP (siRNA-NP) were fabricated using a modified emulsion-solvent evaporation method and characterized for particle size, zeta potential, encapsulation efficiency (EE), and siRNA release. siRNA-NP were decorated with anti-HLA-DR antibody (siRNA-NP-Ab) for targeting delivery to HLA-DR+ dendritic cells (DCs) and homogeneously dispersed in a biodegradable film consisting of poly vinyl alcohol (PVA) and λ-carrageenan. The siRNA-NP-Ab-loaded film (siRNA-NP-Ab-film) was transparent, displayed suitable physicomechanical properties, and was noncytotoxic. Targeting activity was evaluated in a mucosal coculture model consisting of a vaginal epithelial monolayer (VK2/E6E7 cells) and differentiated KG-1 cells (HLA-DR+ DCs). siRNA-NP-Ab were rapidly released from the film and were able to penetrate the epithelial layer to be taken up by differentiated KG-1 cells. siRNA-NP-Ab demonstrated higher targeting activity and significantly higher knockdown of synaptosome-associated 23-kDa protein (SNAP-23) mRNA and protein when compared to siRNA-NP without antibody conjugation. Overall, these data suggest that our novel siRNA-NP-Ab-film may be a promising platform for preventing HIV infection within the female genital tract.

Assessing the potential of the Woman's Condom for vaginal drug delivery

BACKGROUND

The Woman's Condom is a new female condom that uses a dissolvable polyvinyl alcohol capsule to simplify vaginal insertion. This preclinical study assessed the feasibility to incorporate an antiviral drug, UC781, into the Woman's Condom capsule, offering a unique drug delivery platform.

STUDY DESIGN

UC781 capsules were fabricated using methods from the development of the Woman's Condom capsules as well as those used in vaginal film development. Capsules were characterized to evaluate physical/chemical attributes, Lactobacillus compatibility, in vitro safety and bioactivity, and condom compatibility.

RESULTS

Two UC781 capsule platforms were assessed. Capsule masses (mg; mean±SD) for platforms 1 and 2 were 116.50±18.22 and 93.80±8.49, respectively. Thicknesses were 0.0034±0.0004 in and 0.0033±0.0004 in. Disintegration times were 11±3 s and 5±1 s. Puncture strengths were 21.72±3.30 N and 4.02±0.83 N. Water content measured 6.98±1.17% and 7.04±1.92%. UC781 content was 0.59±0.05 mg and 0.77±0.11 mg. Both platforms retained in vitro bioactivity and were nontoxic to TZM-bl cells and Lactobacillus. Short-term storage of UC781 capsules with the Woman's Condom pouch did not decrease condom mechanical integrity.

CONCLUSIONS

UC781 was loaded into a polymeric capsule similar to that of the Woman's Condom product. This study highlights the potential use of the Woman's Condom as a platform for vaginal delivery of drugs relevant to sexual/reproductive health, including those for short- or long-acting HIV prevention.

IMPLICATIONS

We determined the proof-of-concept feasibility of incorporation of an HIV-preventative microbicide into the Woman's Condom capsule. This study highlights various in vitro physical and chemical evaluations as well as bioactivity and safety assessments necessary for vaginal product development related to female sexual and reproductive health.

Vaginal Microbicide Film Combinations of Two Reverse Transcriptase Inhibitors, EFdA and CSIC, for the Prevention of HIV-1 Sexual Transmission

PURPOSE

EFdA is a potent nucleoside reverse transcriptase inhibitor (NRTI) with activity against a wide spectrum of wild-type and drug resistant HIV-1 variants. CSIC is a tight-binding non-nucleoside reverse transcriptase inhibitor (NNRTI) with demonstrated anti-HIV properties important for use in topical prevention of HIV transmission. The objective of this study was to develop and characterize film-formulated EFdA and CSIC for use as a female-controlled vaginal microbicide to prevent sexual transmission of HIV.

METHODS

Assessments of EFdA- and CSIC-loaded films included physicochemical characteristics, in vitro cytotoxicity, epithelia integrity studies, compatibility with the normal vaginal Lactobacillus flora and anti-HIV bioactivity evaluations.

RESULTS

No significant change in physicochemical properties or biological activity of the combination films were noted during 3 months storage. In vitro cytotoxicity and bioactivity testing showed that 50% cytotoxic concentration (CC50) of either EFdA or CSIC was several orders of magnitude higher than the 50% effective concentration (EC50) values. Film-formulated EFdA and CSIC combination showed additive inhibitory activity against wild type and drug-resistant variants of HIV. Epithelial integrity studies demonstrated that the combination vaginal film had a much lower toxicity to HEC-1A monolayers compared to that of VCF®, a commercial vaginal film product containing nonoxynol-9. Polarized ectocervical explants showed films with drug alone or in combination were effective at preventing HIV infection.

CONCLUSIONS

Our data suggest that vaginal microbicide films containing a combination of the NRTI EFdA and the NNRTI CSIC have potential to prevent HIV-1 sexual transmission.

Development and characterization of a solid dispersion film for the vaginal application of the anti-HIV microbicide UAMC01398

The purpose of this work was to design and evaluate a vaginal film delivery system for UAMC01398, a novel non-nucleoside reverse transcriptase inhibitor currently under investigation for use as an anti-HIV microbicide. UAMC01398 (1mg) films consisting of hydroxypropylmethylcellulose (HPMC) and polyethylene glycol 400 (PEG400) in different ratios were prepared by solvent evaporation. Based on its flexibility, softness and translucent appearance, the 30% PEG400 and 70% HPMC containing film was selected for further assessment. The vaginal film formulation was fast-dissolving (<10 min in 1 mL of vaginal fluid simulant), stable up to at least one month and safe toward epithelial cells and lactobacilli. Furthermore, formulating UAMC01398 into the film dosage form did not influence its antiviral activity. Powder X-ray diffraction revealed the amorphous nature of the UAMC01398 film, resulting in enhanced compound permeation across the epithelial HEC-1A cell layer, presumably owing to the induction of supersaturation. The in vivo vaginal tissue uptake of UAMC01398 in rabbits, as measured by systemic concentrations, was increased compared to the previously established non-solubilizing gel (significant difference) and sulfobutyl ether-β-cyclodextrin (5%) containing gel. To conclude, we identified a film formulation suitable for the vaginal delivery of UAMC01398.

Manufacturing scale-up of electrospun poly(vinyl alcohol) fibers containing tenofovir for vaginal drug delivery

Electrospun fibers containing antiretroviral drugs have recently been investigated as a new dosage form for topical microbicides against HIV-1. However, little work has been done to evaluate the scalability of the fiber platform for pharmaceutical production of medical fabrics. Scalability and cost-effectiveness are essential criteria in developing fibers as a practical platform for use as a microbicide and for translation to clinical use. To address this critical gap in the development of fiber-based vaginal dosage forms, we assessed the scale-up potential of drug-eluting fibers delivering tenofovir (TFV), a nucleotide reverse transcriptase inhibitor and lead compound for topical HIV-1 chemoprophylaxis. Here we describe the process of free-surface electrospinning to scale up production of TFV fibers, and evaluate key attributes of the finished products such as fiber morphology, drug crystallinity, and drug loading and release kinetics. Poly(vinyl alcohol) (PVA) containing up to 60 wt% TFV was successfully electrospun into fibers using a nozzle-free production-scale electrospinning instrument. Actual TFV loading in fibers increased with increasing weight percent TFV in solution, and encapsulation efficiency was improved by maintaining TFV solubility and preventing drug sedimentation during batch processing. These results define important solution and processing parameters for scale-up production of TFV drug-eluting fibers by wire electrospinning, which may have significant implications for pharmaceutical manufacturing of fiber-based medical fabrics for clinical use.

Formulation and characterization of polymeric films containing combinations of antiretrovirals (ARVs) for HIV prevention

PURPOSE

To develop polymeric films containing dual combinations of anti-HIV drug candidate tenofovir, maraviroc and dapivirine for vaginal application as topical microbicides.

METHODS

A solvent casting method was used to manufacture the films. Solid phase solubility was used to identify potential polymers for use in the film formulation. Physical and chemical properties (such as water content, puncture strength and in vitro release) and product stability were determined. The bioactivity of the film products against HIV was assessed using the TZM-bl assay and a cervical explant model.

RESULTS

Polymers identified from the solid phase solubility study maintained tenofovir and maraviroc in an amorphous state and prevented drug crystallization. Three combination film products were developed using cellulose polymers and polyvinyl alcohol. The residual water content in all films was <10% (w/w). All films delivered the active agents with release of >50% of film drug content within 30 min. Stability testing confirmed that the combination film products were stable for 12 months at ambient temperature and 6 months under stressed conditions. Antiviral activity was confirmed in TZM-bl and cervical explant models.

CONCLUSIONS

Polymeric films can be used as a stable dosage form for the delivery of antiretroviral combinations as microbicides.

Electrospun solid dispersions of Maraviroc for rapid intravaginal preexposure prophylaxis of HIV

The development of topical anti-human immunodeficiency virus (HIV) microbicides may provide women with strategies to protect themselves against sexual HIV transmission. Pericoital drug delivery systems intended for use immediately before sex, such as microbicide gels, must deliver high drug doses for maximal effectiveness. The goal of achieving a high antiretroviral dose is complicated by the need to simultaneously retain the dose and quickly release drug compounds into the tissue. For drugs with limited solubility in vaginal gels, increasing the gel volume to increase the dose can result in leakage. While solid dosage forms like films and tablets increase retention, they often require more than 15 min to fully dissolve, potentially increasing the risk of inducing epithelial abrasions during sex. Here, we demonstrate that water-soluble electrospun fibers, with their high surface area-to-volume ratio and ability to disperse antiretrovirals, can serve as an alternative solid dosage form for microbicides requiring both high drug loading and rapid hydration. We formulated maraviroc at up to 28 wt% into electrospun solid dispersions made from either polyvinylpyrrolidone or poly(ethylene oxide) nanofibers or microfibers and investigated the role of drug loading, distribution, and crystallinity in determining drug release rates into aqueous media. We show here that water-soluble electrospun materials can rapidly release maraviroc upon contact with moisture and that drug delivery is faster (less than 6 min under sink conditions) when maraviroc is electrospun in polyvinylpyrrolidone fibers containing an excipient wetting agent. These materials offer an alternative dosage form to current pericoital microbicides.

Analysis of vaginal microbicide film hydration kinetics by quantitative imaging refractometry

We have developed a quantitative imaging refractometry technique, based on holographic phase microscopy, as a tool for investigating microscopic structural changes in water-soluble polymeric materials. Here we apply the approach to analyze the structural degradation of vaginal topical microbicide films due to water uptake. We implemented transmission imaging of 1-mm diameter film samples loaded into a flow chamber with a 1.5×2 mm field of view. After water was flooded into the chamber, interference images were captured and analyzed to obtain high resolution maps of the local refractive index and subsequently the volume fraction and mass density of film material at each spatial location. Here, we compare the hydration dynamics of a panel of films with varying thicknesses and polymer compositions, demonstrating that quantitative imaging refractometry can be an effective tool for evaluating and characterizing the performance of candidate microbicide film designs for anti-HIV drug delivery.

Efficacy of Tenofovir 1% Vaginal Gel in Reducing the Risk of HIV-1 and HSV-2 Infection

Human Immunodeficiency Virus (HIV) is a retrovirus that can result in rare opportunistic infections occurring in humans. The onset of these infections is known as Acquired Immune Deficiency Syndrome (AIDS). Sexual transmission is responsible for the majority of infections 1, resulting in transmission of HIV due to infected semen or vaginal and cervical secretions containing infected lymphocytes. HIV microbicides are formulations of chemical or biological agents that can be applied to the vagina or rectum with the intention of reducing the acquisition of HIV. Tenofovir is an NRTI that is phosphorylated by adenylate kinase to tenofovir diphosphate, which in turn competes with deoxyadeosine 5’-triphosphate for incorporation into newly synthesized HIV DNA. Once incorporated, tenofovir diphosphate results in chain termination, thus inhibiting viral replication. Tenofovir has been formulated into a range of vaginal formulations, such as rings, tablets gels and films. It has been shown to safe and effective in numerous animal models, while demonstrating safety and acceptability in numerous human trials. The most encouraging results came from the CAPRISA 004 clinical trial which demonstrated that a 1% Tenofovir vaginal gel reduced HIV infection by approximately 39%.

Microbicides for the Treatment of Sexually Transmitted HIV Infections

Approximately 34 million people were living with human immunodeficiency virus (HIV-1) at the end of 2011. From the last two decades, researchers are actively involved in the development of an effective HIV-1 treatment, but the results intended are still doubtful about the eradication of HIV. The HIV-1 virus has gone from being an "inherently untreatable" infectious agent to the one liable to be affected by a range of approved therapies. Candidate microbicides have been developed to target specific steps in the process of viral transmission. Microbicides are self-administered agents that can be applied to vaginal or rectal mucosal surfaces with the aim of preventing, or reducing, the transmission of sexually transmitted infections (STIs) including HIV-1. The development of efficient, widely available, and low-cost microbicides to prevent sexually transmitted HIV infections should be given high priority. In this review, we studied the various forms of microbicides, their mechanism of action, and their abundant approaches to control the transmission of sexually transmitted infections (STIs).

Development of a vaginal delivery film containing EFdA, a novel anti-HIV nucleoside reverse transcriptase inhibitor

The aim of this work was to develop a fast-dissolving film formulation containing EFdA for potential use as a topical vaginal microbicide for prevention of HIV sexual transmission. Solid state compatibility approaches were used to screen commonly used polymers for formulation development. Factorial design and desirability function were used to investigate the effect of two variables, the ratio of the polymers and the concentration of selected plasticizer on four mechanical responses including tensile strength, elongation at break, toughness and elastic modulus for optimization of the film formulation. Assessments of EFdA-loaded films included physicochemical characteristics, in vitro cytotoxicity, epithelia integrity, ex vivo permeability and bioactivity test. The optimal placebo film was composed of PVA, HPMC E5 and propylene glycol (7:3:3, w/w), and its mechanical characteristics were comparable to those of VCF(®) film (a commercial vaginal film product). Permeability studies using human ectocervical explants showed that there was no significant difference in cumulative permeated amount of EFdA between EFdA film and free EFdA. The results of in vitro cytotoxicity and bioactivity testing showed that 50% cytotoxic concentration (CC50) was several orders of magnitude higher than 50% effective concentration (EC50) of EFdA. Furthermore, epithelial integrity study showed that EFdA-loaded film had a much lower toxicity to HEC-1A cell monolayers as compared to VCF(®). Therefore, EFdA-loaded vaginal film may be considered as a promising vaginal microbicide for HIV prevention.

Preformulation studies of EFdA, a novel nucleoside reverse transcriptase inhibitor for HIV prevention

4'-Ethynyl-2-fluoro-2'-deoxyadenosine (EFdA) is a novel nucleoside analog of great interest because of its superior activity against wild-type and multidrug-resistant HIV-1 strains, and favorable safety profiles in vitro and in vivo. The aim of this work was to provide preformulation information of EFdA important for delivery system development. A simple, accurate and specific reverse-phase high performance liquid chromatographic (RP-HPLC) method with UV detection was developed for quantification of EFdA. In addition, physicochemical characterizations including pH solubility profile, octanol/water partition coefficient (Log Po/w), DSC analysis, field emission scanning electron microscopy, and stability studies under various conditions were conducted. EFdA existed in planar or flake shape, with a melting point of ∼130 °C, and had a pH dependent solubility. The log Po/w value of EFdA was -1.19. The compound was stable upon exposure to pH levels from 3 to 9 and showed good stability at elevated temperature (65 °C). In vitro cytotoxicity assessments were performed in two different epithelial cell lines. In cell-based studies, the EFdA selectivity index (50% cytotoxic concentration [CC50] values/50% effective concentration [EC50]) was found to be greater than 1 × 10(3). Permeability studies using cell- and tissue-based models showed that EFdA had an apparent permeability coefficient (Papp) <1 × 10(-6)cm/s and that the paracelluar pathway was the dominant transport route for EFdA. Overall, EFdA possesses favorable characteristics for further formulation development.

Vaginal films for drug delivery

Vaginal dosage forms have been studied in relation to many drugs as the vagina presents several advantages as a site for drug delivery, such as large surface area, rich blood supply, avoidance of the first-pass effect, relatively high permeability to several drugs, and self-insertion. Traditional vaginal dosage forms have been associated with disadvantages such as low residence time and discomfort and have been surpassed by newly designed drug delivery systems, particularly those based on bioadhesive polymers. Vaginal films are solid dosage forms that rapidly dissolve in contact with vaginal fluids and are unlikely to be associated with leakage and messiness. They have been studied for some female genital problems, aiming either contraceptive, antimicrobial, or microbicide effects. Precise and complex processes of manufacturing and characterization are required to achieve successful film formulation. Although scarce, the available user's acceptability studies show promising results. Vaginal films gather a lack of opportunities for both therapeutic and prophylactic actions, and therefore should be considered when designing and developing new vaginal drug delivery systems.

Protein-coated nanoparticles embedded in films as delivery platforms

Objectives

This work aimed to evaluate the performance of nanoparticle-loaded films based on matrices of polymethacrylates and hydroxypropylmethylcellulose (HPMC) intended for delivery of macromolecules.

Methods

Lysozyme (Lys)-loaded nanoparticles were manufactured by antisolvent co-precipitation. After size, loading efficiency and stability characterization, the selected batch of particles was further formulated into films. Films were characterized for mechanical properties, mucoadhesion, Lys release and activity after manufacture.

Key findings

We found that protein-coated nanoparticles could be obtained in USP phosphate buffer pH 6.8. Particles obtained at pH 6.8 had a z-average of 347.2 nm, a zeta-potential of 21.9 mV and 99.2% remaining activity after manufacture. This formulation was further studied for its application in films for buccal delivery. Films loaded with nanoparticles that contained Eudragit RLPO (ERL) exhibited excellent mechanical and mucoadhesive properties. Due to its higher water-swelling and solubility compared with ERL, the use of HPMC allowed us to tailor the release of Lys from films. The formulation composed of equal amounts of ERL and HPMC revealed a sustained release over 4 h, with Lys remaining fully active at the end of the study.

Conclusions

Mucoadhesive films containing protein-coated nanoparticles are promising carriers for the buccal delivery of proteins and peptides in a stable form.

Current status of topical antiretroviral chemoprophylaxis

PURPOSE OF REVIEW

Recent studies suggest that the vaginal delivery of antiretroviral (ARV) agents - such as tenofovir, dapivirine and UC781 - may be a promising way to reduce the high rates of HIV infection among women in developing countries. This review examines these developments.

RECENT FINDINGS

The Microbicide Trials Network 003 study, a large phase IIb trial, was unable to show that daily dosing with 1% tenofovir vaginal gel was effective for HIV prevention. Nevertheless, preclinical and early-phase clinical trials suggest that ARV drugs - formulated in vaginal gels, rings, films, tablets and diaphragms - could be effective for HIV chemoprophylaxis.

SUMMARY

Investigations of topical chemoprophylaxis methods have seen mixed results in the past 12-18 months. Product adherence may prove to be one of the field's greatest challenges. Phase II and III trials continue to explore different dosing strategies for topical products that contain one or more ARV agents.

Microbicide dosage forms

Microbicides are topically applied, user controlled dosage forms that are being developed to prevent the transmission of HIV during coitus. Early candidates focused on coitally dependent dosage forms such as gels and creams. More recent development has focused on broadening the coitally dependent options through the introduction of films and fast dissolving tablets. Additionally, it has become important to have longer acting products to minimize the burden of user compliance and thus vaginal rings have been developed providing sustained delivery of antiretroviral drugs. This chapter discusses the history of microbicides along with a detailed description of coitally dependent products, gels, films, tablets diaphragms, as well as coitally independent dosage forms such as vaginal rings and the introduction of a new technology, electrospun fibers.

Drug-eluting fibers for HIV-1 inhibition and contraception

Multipurpose prevention technologies (MPTs) that simultaneously prevent sexually transmitted infections (STIs) and unintended pregnancy are a global health priority. Combining chemical and physical barriers offers the greatest potential to design effective MPTs, but integrating both functional modalities into a single device has been challenging. Here we show that drug-eluting fiber meshes designed for topical drug delivery can function as a combination chemical and physical barrier MPT. Using FDA-approved polymers, we fabricated nanofiber meshes with tunable fiber size and controlled degradation kinetics that facilitate simultaneous release of multiple agents against HIV-1, HSV-2, and sperm. We observed that drug-loaded meshes inhibited HIV-1 infection in vitro and physically obstructed sperm penetration. Furthermore, we report on a previously unknown activity of glycerol monolaurate (GML) to potently inhibit sperm motility and viability. The application of drug-eluting nanofibers for HIV-1 prevention and sperm inhibition may serve as an innovative platform technology for drug delivery to the lower female reproductive tract.