Miconazole: a historical perspective

Novel Therapeutic Hybrid Systems Using Hydrogels and Nanotechnology: A Focus on Nanoemulgels for the Treatment of Skin Diseases

Topical and transdermal drug delivery are advantageous administration routes, especially when treating diseases and conditions with a skin etiology. Nevertheless, conventional dosage forms often lead to low therapeutic efficacy, safety issues, and patient noncompliance. To tackle these issues, novel topical and transdermal platforms involving nanotechnology have been developed. This review focuses on the latest advances regarding the development of nanoemulgels for skin application, encapsulating a wide variety of molecules, including already marketed drugs (miconazole, ketoconazole, fusidic acid, imiquimod, meloxicam), repurposed marketed drugs (atorvastatin, omeprazole, leflunomide), natural-derived compounds (eucalyptol, naringenin, thymoquinone, curcumin, chrysin, brucine, capsaicin), and other synthetic molecules (ebselen, tocotrienols, retinyl palmitate), for wound healing, skin and skin appendage infections, skin inflammatory diseases, skin cancer, neuropathy, or anti-aging purposes. Developed formulations revealed adequate droplet size, PDI, viscosity, spreadability, pH, stability, drug release, and drug permeation and/or retention capacity, having more advantageous characteristics than current marketed formulations. In vitro and/or in vivo studies established the safety and efficacy of the developed formulations, confirming their therapeutic potential, and making them promising platforms for the replacement of current therapies, or as possible adjuvant treatments, which might someday effectively reach the market to help fight highly incident skin or systemic diseases and conditions.

Green chromatographic methods for determination of co-formulated lidocaine hydrochloride and miconazole nitrate along with an endocrine disruptor preservative and potential impurity

Recently, green analytical chemistry (GAC) is a key issue towards the idea of sustainability, the analytical community is focused on developing analytical methods that incorporate green chemistry principles to minimize adverse impacts on the environment and humans. Herein, we present 2 sustainable, selective, and validated chromatographic methods. Initially, lidocaine hydrochloride (LDC) and miconazole nitrate (MIC) with two preservatives; methyl paraben (MTP) and saccharin sodium (SAC) were chromatographed via TLC-densitometric method which employed ethyl acetate: methanol: formic acid (9:1:0.1, by volume) as the mobile phase with UV detection at 220.0 nm, good correlation was obtained in the range of 0.3-3.0 µg/band for MIC and LDC. Following that, RP-HPLC was successfully applied for separating quinary mixture of LDC, MIC, MTP, SAC along with LDC impurity; dimethyl aniline (DMA) using C18 column, and a gradient green mobile phase composed of methanol and phosphate buffer (pH 6.0) in different ratios with a flow rate 1.5 mL/min and UV detection at 210.0 nm, linearity ranges from 1.00 to 100.00 µg/mL for MIC, 2.00-100.00 µg/mL for LDC and 1.00--20.00 µg/mL for MTP and DMA. No records to date regarding the determination of the two drugs, besides MTP and DMA. The proposed methods were validated according to the ICH guidelines and applied successfully to the analysis of the compounds. The methods' results were statistically compared to those obtained by applying the reported one, indicating no significant difference regarding both accuracy and precision. The methods' greenness profiles have been assessed and compared with those of the reported method using different assessment tools.

Antifungals: From Pharmacokinetics to Clinical Practice

The use of antifungal drugs started in the 1950s with polyenes nystatin, natamycin and amphotericin B-deoxycholate (AmB). Until the present day, AmB has been considered to be a hallmark in the treatment of invasive systemic fungal infections. Nevertheless, the success and the use of AmB were associated with severe adverse effects which stimulated the development of new antifungal drugs such as azoles, pyrimidine antimetabolite, mitotic inhibitors, allylamines and echinochandins. However, all of these drugs presented one or more limitations associated with adverse reactions, administration route and more recently the development of resistance. To worsen this scenario, there has been an increase in fungal infections, especially in invasive systemic fungal infections that are particularly difficult to diagnose and treat. In 2022, the World Health Organization (WHO) published the first fungal priority pathogens list, alerting people to the increased incidence of invasive systemic fungal infections and to the associated risk of mortality/morbidity. The report also emphasized the need to rationally use existing drugs and develop new drugs. In this review, we performed an overview of the history of antifungals and their classification, mechanism of action, pharmacokinetic/pharmacodynamic (PK/PD) characteristics and clinical applications. In parallel, we also addressed the contribution of fungi biology and genetics to the development of resistance to antifungal drugs. Considering that drug effectiveness also depends on the mammalian host, we provide an overview on the roles of therapeutic drug monitoring and pharmacogenomics as means to improve the outcome, prevent/reduce antifungal toxicity and prevent the emergence of antifungal resistance. Finally, we present the new antifungals and their main characteristics.

Mebendazole Inhibits Histoplasma capsulatum In Vitro Growth and Decreases Mitochondrion and Cytoskeleton Protein Levels

Histoplasmosis is a frequent mycosis in people living with HIV/AIDS and other immunocompromised hosts. Histoplasmosis has high rates of mortality in these patients if treatment is unsuccessful. Itraconazole and amphotericin B are used to treat histoplasmosis; however, both antifungals have potentially severe pharmacokinetic drug interactions and toxicity. The present study determined the minimal inhibitory and fungicidal concentrations of mebendazole, a drug present in the NIH Clinical Collection, to establish whether it has fungicidal or fungistatic activity against Histoplasma capsulatum. Protein extracts from H. capsulatum yeasts, treated or not with mebendazole, were analyzed by proteomics to understand the metabolic changes driven by this benzimidazole. Mebendazole inhibited the growth of 10 H. capsulatum strains, presenting minimal inhibitory concentrations ranging from 5.0 to 0.08 µM. Proteomics revealed 30 and 18 proteins exclusively detected in untreated and mebendazole-treated H. capsulatum yeast cells, respectively. Proteins related to the tricarboxylic acid cycle, cytoskeleton, and ribosomes were highly abundant in untreated cells. Proteins related to the nitrogen, sulfur, and pyrimidine metabolisms were enriched in mebendazole-treated cells. Furthermore, mebendazole was able to inhibit the oxidative metabolism, disrupt the cytoskeleton, and decrease ribosomal proteins in H. capsulatum. These results suggest mebendazole as a drug to be repurposed for histoplasmosis treatment.

Efficacy and safety of miconazole muco-adhesive tablet versus itraconazole in oropharyngeal candidiasis: A randomized, multi-centered, double-blind, phase 3 trial

Oropharyngeal candidiasis (OPC) is an opportunistic infection treated with anti-fungal agents. Herein, we evaluate the efficacy and safety of miconazole buccal tablets (MBT) and itraconazole capsules in the localized treatment of patients with OPC. In this multi-centered, double-blinded, phase III trial (CTR20130414), both males and non-pregnant females (≥18 years) with OPC were randomized (1:1) to MBT plus placebo (experimental group) or itraconazole capsules plus placebo (control group). The primary endpoint was clinical cure at the end-of-treatment period [visit 4 (V4)] while secondary endpoints were clinical remission rates, partial remission rates, mycological cure, clinical relapse, and adverse events (AEs). All endpoints were statistically analyzed in both the full analysis set (FAS) and per-protocol (PP) set. A total of 431 (experimental: 216; control: 215) subjects were included. At V4, in the FAS set, the clinical cure was achieved in 68% and 59% patients in experimental and control groups, respectively with a treatment difference of 9% [95% confidence interval (CI): -1,19; P < .001] demonstrating non-inferiority of MBT over itraconazole. At V4, mycological cure rates were 68.2% and 42.0% in the experimental group and control groups (P < .001), respectively in FAS. The relapse rates were 5.4% and 6.6%, respectively, in the experimental and control groups. A total of 210 patients experienced AEs during treatment with 47.7% in the experimental group and 49.8% in the control group with no deaths. This study demonstrated that once-daily treatment with MBT was non-inferior to itraconazole with higher mycological cure rates and was tolerable with mild AE in patients with OPC.

Emerging Trends in the Use of Topical Antifungal-Corticosteroid Combinations

A broad range of topical antifungal formulations containing miconazole or terbinafine as actives are commonly used as efficacious choices for combating fungal skin infections. Their many benefits, owing to their specific mechanism of action, include their ability to target the site of infection, enhance treatment efficacy and reduce the risk of systemic side effects. Their proven efficacy, and positioning in the treatment of fungal skin infections, is enhanced by high patient compliance, especially when appropriate vehicles such as creams, ointments and gels are used. However, inflammation as a result of fungal infection can often impede treatment, especially when combined with pruritus (itch), an unpleasant sensation that elicits an urge to scratch. The scratching that occurs in response to pruritus frequently accelerates skin damage, ultimately aggravating and spreading the fungal infection. To help overcome this issue, a topical antifungal-corticosteroid combination consisting of miconazole or terbinafine and corticosteroids of varying potencies should be used. Due to their inherent benefits, these topical antifungal-corticosteroid combinations can concomitantly and competently attenuate inflammation, relieve pruritus and treat fungal infection.

A comparison of three crystalline forms of miconazole: solvent-free, ethanol monosolvate and hemihydrate

The crystal structures of miconazole {MIC, C18H14Cl4N2O, systematic name (RS)-1-[2-(2,4-dichlorobenzyloxy)-2-(2,4-dichlorophenyl)ethyl]-1H-imidazole}, its ethanol monosolvate (C18H14Cl4N2O·C2H5OH) and its hemihydrate (C18H14Cl4N2O·0.5H2O) were compared. A detailed comparison of the molecular conformation of the miconazole molecules showed a structural similarity of the solvate forms, whereas the unsolvated form is related to the gas-phase structure. This suggests that the molecular conformation of miconazole is influenced by solvent molecules. The crystal architectures of the considered solvatomorphs are differentiated by the intermolecular interactions formed by ethanol and water molecules. The structural studies are enriched by Hirshfeld surface and energy framework analysis. The pairwise model energies of the dominant contacts were estimated to be in the range 20–70 kJ mol−1. It is interesting that the contribution of dispersive forces predominates over the electrostatic forces.

Emerging Antifungal Targets and Strategies

Despite abundant research in the field of antifungal drug discovery, fungal infections remain a significant healthcare burden. There is an emerging need for the development of novel antifungals since those currently available are limited and do not completely provide safe and secure protection. Since the current knowledge regarding the physiology of fungal cells and the infection mechanisms is greater than ever, we have the opportunity to use this for the development of novel generations of antifungals. In this review, we selected and summarized recent studies describing agents employing different antifungal mechanisms. These mechanisms include interference with fungal resistance, including impact on the efflux pumps and heat shock protein 90. Additionally, interference with virulence factors, such as biofilms and hyphae; the impact on fungal enzymes, metabolism, mitochondria, and cell wall; and antifungal vaccines are explored. The agents investigated belong to different classes of natural or synthetic molecules with significant attention given also to plant extracts. The efficacy of these antifungals has been studied mainly in vitro with some in vivo, and clinical studies are needed. Nevertheless, there is a large quantity of products employing novel antifungal mechanisms that can be further explored for the development of new generation of antifungals.

Potent antifungal agents and use of nanocarriers to improve delivery to the infected site: A systematic review

There are four major classes of antifungals with the predominant mechanism of action being targeting of cell wall or cell membrane. As in other drugs, low solubility of these compounds has led to low bioavailability in target tissues. Enhanced drug dosages have effects such as toxicity, drug-drug interactions, and increased drug resistance by fungi. This article reviews the current state-of-the-art of antifungals, structure, mechanism of action, other usages, and toxic side effects. The emergence of nanoformulations to transport and uniformly release cargo at the target site is a boon in antifungal treatment. The article details research that lead to the development of nanoformulations of antifungals and potential advantages and avoidance of the lacunae characterizing conventional drugs. A range of nanoformulations based on liposomes, polymers are in various stages of research and their potential advantages have been brought out. It could be observed that under similar dosages, test models, and duration, nanoformulations provided enhanced activity, reduced toxicity, higher uptake and higher immunostimulatory effects. In most instances, the mechanism of antifungal activity of nanoformulations was similar to that of regular antifungal. There are possibilities of coupling multiple antifungals on the same nano-platform. Increased activity coupled with multiple mechanisms of action presents for nanoformulations a tremendous opportunity to overcome antifungal resistance. In the years to come, robust methods for the preparation of nanoformulations taking into account the repeatability and reproducibility in action, furthering the studies on nanoformulation toxicity and studies of human models are required before extensive use of nanoformulations as a prescribed drug.

Geminal Diheteroatomic Motifs: Some Applications of Acetals, Ketals, and Their Sulfur and Nitrogen Homologues in Medicinal Chemistry and Drug Design

Acetals and ketals and their nitrogen and sulfur homologues are often considered to be unconventional and potentially problematic scaffolding elements or pharmacophores for the design of orally bioavailable drugs. This opinion is largely a function of the perception that such motifs might be chemically unstable under the acidic conditions of the stomach and upper gastrointestinal tract. However, even simple acetals and ketals, including acyclic molecules, can be sufficiently robust under acidic conditions to be fashioned into orally bioavailable drugs, and these structural elements are embedded in many effective therapeutic agents. The chemical stability of molecules incorporating geminal diheteroatomic motifs can be modulated by physicochemical design principles that include the judicious deployment of proximal electron-withdrawing substituents and conformational restriction. In this Perspective, we exemplify geminal diheteroatomic motifs that have been utilized in the discovery of orally bioavailable drugs or drug candidates against the backdrop of understanding their potential for chemical lability.

In Silico Screening of the DrugBank Database to Search for Possible Drugs against SARS-CoV-2

Coronavirus desease 2019 (COVID-19) is responsible for more than 1.80 M deaths worldwide. A Quantitative Structure-Activity Relationships (QSAR) model is developed based on experimental pIC50 values reported for a structurally diverse dataset. A robust model with only five descriptors is found, with values of R2 = 0.897, Q2LOO = 0.854, and Q2ext = 0.876 and complying with all the parameters established in the validation Tropsha's test. The analysis of the applicability domain (AD) reveals coverage of about 90% for the external test set. Docking and molecular dynamic analysis are performed on the three most relevant biological targets for SARS-CoV-2: main protease, papain-like protease, and RNA-dependent RNA polymerase. A screening of the DrugBank database is executed, predicting the pIC50 value of 6664 drugs, which are IN the AD of the model (coverage = 79%). Fifty-seven possible potent anti-COVID-19 candidates with pIC50 values > 6.6 are identified, and based on a pharmacophore modelling analysis, four compounds of this set can be suggested as potent candidates to be potential inhibitors of SARS-CoV-2. Finally, the biological activity of the compounds was related to the frontier molecular orbitals shapes.

Prospective trial for the clinical efficacy of anogenital skin care with miconazole nitrate-containing soap for diaper candidiasis

Anogenital skin care for the elderly remains an umbrella term concerning protective and non-interventional regimens, particularly for ordinary diaper users. Our recent investigation has demonstrated the preventive effect of daily anogenital washing with miconazole nitrate-containing soap to the development of diaper candidiasis. We extended this work to cover our hypothesis as to whether the miconazole soap has a therapeutic benefit in genital candidiasis. The study outline includes: (i) the enrollment of 21 bedridden inpatients (84 ± 9 years; eight men and 13 women) who were diagnosed clinically and mycologically with genital candidiasis, and who had never received topical and/or systemic antifungal agents; (ii) administration of anogenital washing with 0.75% miconazole-containing soap once daily for 4 weeks; and (iii) assessment of clinical symptoms and detection of Candida materials by culture and microscopic examination. As assessed by clinical symptom scoring for incontinence-associated dermatitis (IAD), the ratio of patients with severe to moderate symptoms dramatically decreased by 2 weeks and 10 of 21 patients became symptom-free at 4 weeks. The IAD clinical severity score was significantly decreased at 4 weeks. Compared with the baseline positivity, both microscopic and cultured Candida-positive rates were significantly decreased at 4 weeks after washing. All culture-detected fungi were Candida albicans. Severe adverse events did not occur in all participants. Individual medical and risk factors had no significant correlation with clinical severity and duration of candidiasis on variance analysis. In conclusion, topical washing with miconazole soap is a safe and reliable non-medical approach for soothing diaper-associated genital candidiasis in bedridden inpatients in whom it is difficult to perform prompt medical examination.

The Chemistry of Drugs to Treat Candida albicans

Background::

Candida species are in various parts of the human body as commensals. However, they can cause local mucosal infections and, sometimes, systemic infections in which Candida species can spread to all major organs and colonize them.

Objective::

For the effective treatment of the mucosal infections and systemic life-threatening fungal diseases, a considerably large number of antifungal drugs have been developed and used for clinical purposes that comprise agents from four main drug classes: the polyenes, azoles, echinocandins, and antimetabolites.

Method: :

The synthesis of some of these drugs is available, allowing synthetic modification of the molecules to improve the biological activity against Candida species. The synthetic methodology for each compound is reviewed.

Results: :

The use of these compounds has caused a high-level resistance against these drugs, and therefore, new antifungal substances have been described in the last years. The organic synthesis of the known and new compounds is reported.

Conclusion: :

This article summarizes the chemistry of the existing agents, both the old drugs and new drugs, in the treatment of infections due to C. albicans, including the synthesis of the existing drugs.

Development, characterization, and in vitro-in vivo evaluation of polymeric nanoparticles containing miconazole and farnesol for treatment of vulvovaginal candidiasis

Vulvovaginal candidiasis (VVC) is caused mainly by the opportunistic fungus Candida albicans, and its yeast to hyphae transition is considered a major virulence factor. Farnesol is a molecule that inhibits yeast to hyphae transition. The increased incidence of VVC has influenced a need for developing new therapeutic strategies. The objective was to develop a mucoadhesive nanostructured system composed of miconazole and farnesol co-encapsulated within chitosan nanoparticles. The miconazole presented a minimal inhibitory concentration (MIC) of 1 μg/ml against C. albicans. The farnesol was capable of inhibiting yeast to hyphae transition at levels greater or equal to 300 μM. The combination of miconazole and farnesol showed no change in miconazole MIC. Chitosan nanoparticles containing miconazole and farnesol were prepared by ionic gelation and showed favorable characteristics for use on mucous membranes. They showed size variation and polydispersion index (PDI) after 30 days, but the efficiency of drug encapsulation was maintained. Regarding toxicity in cultured fibroblasts (BALB/c 3T3) the nanoparticles were considered nontoxic. The nanoparticles showed antifungal activity against the C. albicans strain used with MICs of 2.5 μg/ml and 2 μg/ml for nanoparticles containing miconazole or miconazole/farnesol, respectively. Nanoparticles containing farnesol inhibited yeast to hyphae transition at concentrations greater than or equal to 240 μM. The in vivo antifungal activity was assessed in the murine model for VVC. The results suggested that chitosan nanoparticles containing miconazole and farnesol were effective at inhibiting fungal proliferation. Additionally, chitosan nanoparticles containing farnesol were capable of decreasing the pathogenicity of infection, demonstrated through the absence of inflammation.

Pre-Existing Liver Disease and Toxicity of Antifungals

Pre-existing liver disease in patients with invasive fungal infections further complicates their management. Altered pharmacokinetics and tolerance issues of antifungal drugs are important concerns. Adjustment of the dosage of antifungal agents in these cases can be challenging given that current evidence to guide decision-making is limited. This comprehensive review aims to evaluate the existing evidence related to antifungal treatment in individuals with liver dysfunction. This article also provides suggestions for dosage adjustment of antifungal drugs in patients with varying degrees of hepatic impairment, after accounting for established or emerging pharmacokinetic–pharmacodynamic relationships with regard to antifungal drug efficacy in vivo.

Identification of FDA-Approved Drugs as Antivirulence Agents Targeting the pqs Quorum-Sensing System of Pseudomonas aeruginosa

The long-term use of antibiotics has led to the emergence of multidrug-resistant bacteria. A promising strategy to combat bacterial infections aims at hampering their adaptability to the host environment without affecting growth. In this context, the intercellular communication system quorum sensing (QS), which controls virulence factor production and biofilm formation in diverse human pathogens, is considered an ideal target. Here, we describe the identification of new inhibitors of the pqs QS system of the human pathogen Pseudomonas aeruginosa by screening a library of 1,600 U.S. Food and Drug Administration-approved drugs. Phenotypic characterization of ad hoc engineered strains and in silico molecular docking demonstrated that the antifungal drugs clotrimazole and miconazole, as well as an antibacterial compound active against Gram-positive pathogens, clofoctol, inhibit the pqs system, probably by targeting the transcriptional regulator PqsR. The most active inhibitor, clofoctol, specifically inhibited the expression of pqs-controlled virulence traits in P. aeruginosa, such as pyocyanin production, swarming motility, biofilm formation, and expression of genes involved in siderophore production. Moreover, clofoctol protected Galleria mellonella larvae from P. aeruginosa infection and inhibited the pqs QS system in P. aeruginosa isolates from cystic fibrosis patients. Notably, clofoctol is already approved for clinical treatment of pulmonary infections caused by Gram-positive bacterial pathogens; hence, this drug has considerable clinical potential as an antivirulence agent for the treatment of P. aeruginosa lung infections.

Novel Intravaginal Drug Delivery System Based on Molecularly PEGylated Lipid Matrices for Improved Antifungal Activity of Miconazole Nitrate

The aim of this study was to investigate the potential of microparticles based on biocompatible phytolipids [Softisan® 154 (SF) (hydrogenated palm oil) and super-refined sunseed oil (SO)] and polyethylene glycol- (PEG-) 4000 to improve intravaginal delivery of miconazole nitrate (MN) for effective treatment of vulvovaginal candidiasis (VVC). Lipid matrices (LMs) consisting of rational blends of SF and SO with or without PEG-4000 were prepared by fusion and characterized and employed to formulate MN-loaded solid lipid microparticles (SLMs) by melt-homogenization. The SLMs were characterized for physicochemical properties, anticandidal activity, and stability. Spherical discrete microparticles with good physicochemical properties and mean diameters suitable for vaginal drug delivery were obtained. Formulations based on SO:SF (1:9) and containing highest concentrations of PEG-4000 (4 %w/w) and MN (3.0 %w/w) were stable and gave highest encapsulation efficiency (83.05–87.75%) and inhibition zone diameter (25.87±0.94–26.33±0.94 mm) and significantly (p<0.05) faster and more powerful fungicidal activity regarding killing rate constant values (7.10 x 10⁻³–1.09 x 10⁻² min⁻¹) than commercial topical solution of MN (Fungusol®) (8.00 x 10⁻³ min⁻¹) and pure MN sample (5.160 x 10⁻³ min⁻¹). This study has shown that MN-loaded SLMs based on molecularly PEGylated lipid matrices could provide a better option to deal with VVC.

Surface-modified mucoadhesive microgels as a controlled release system for miconazole nitrate to improve localized treatment of vulvovaginal candidiasis

The use of conventional vaginal formulations of miconazole nitrate (MN) in the treatment of deep-seated VVC (vulvovaginal candidiasis) is limited by poor penetration capacity and low solubility of MN, short residence time and irritation at the application site. Surface-modified mucoadhesive microgels were developed to minimize local irritation, enhance penetration capacity and solubility and prolong localized vaginal delivery of MN for effective treatment of deep-seated VVC. Solid lipid microparticles (SLMs) were prepared from matrices consisting of hydrogenated palm oil (Softisan® 154, SF) and super-refined sunseed oil (SO) with or without polyethylene glycol (PEG)-4000, characterized for physicochemical performance and used to prepare mucoadhesive microgels (MMs) encapsulating MN, employing Polycarbophil as bioadhesive polymer. The MMs were evaluated for physicochemical performance and in vitro drug release in simulated vaginal fluid (pH=4.2), whereas mucoadhesive, rheological and stability tests, anticandidal efficacy in immunosuppressed estrogen-dependent female rats and vaginal tolerance test in rabbits were performed with optimized formulation. The amorphicity of 1:9 phytolipid blend (SO:SF) was increased in the presence of PEG-4000. The physicochemical properties of the SLMs and MMs indicated their suitability for vaginal drug delivery. Overall, MN-loaded PEGylated MMs exhibited significantly (p<0.05) more prolonged drug release than non-PEGylated MMs. Additionally, optimized PEGylated MMs was stable at 40±2°C over a period of 6months, viscoelastic, mucoadhesive, non-sensitizing, histopathologically safe and gave remarkably (p<0.05) higher reduction in Candida albicans load (86.06%) than Daktarin® (75.0%) and MN-loaded polymeric-hydrogel (47.74%) in treated rats in 12days. Thus, PEGylated MMs is promising for effective and convenient treatment of VVC.

The Efficacy and Safety of Miconazole Nitrate Mucoadhesive Tablets versus Itraconazole Capsules in the Treatment of Oral Candidiasis: An Open-Label, Randomized, Multicenter Trial

Background

Oral candidiasis (OC) is a common oral fungal infection. Recently, miconazole mucoadhesive tablets have been gaining attention for OC treatment. Despite trials in patients with human immunodeficiency virus and cancer, evidence of its application in the large-scale, general population with OC is lacking. This study aimed to evaluate the efficacy and safety of miconazole nitrate mucoadhesive tablets in comparison with itraconazole capsules for OC treatment.

Methods

The study was a randomized, open-label, parallel-armed, multicenter clinical trial. Totally, 343 patients diagnosed with OC, who met the inclusion criteria, were randomly assigned to either a treatment group that received miconazole nitrate mucoadhesive tablets (10 mg) once daily or a control group that received itraconazole capsules (100 mg QD) for 2 weeks, and were followed up for 2 weeks. The clinical cure, improvement of clinical symptoms/signs, mycologic cure, and safety were evaluated.

Results

The mucoadhesive tablets (n = 171) did not show inferiority to itraconazole (n = 172) in the treatment of OC. At the end of the 14-day treatment, the clinical cure rates were 45.29% and 41.76% in the miconazole and itraconazole groups, respectively (P = 0.3472). At the end of the 14-day follow-up, the clinical cure rates were 51.18% and 41.76% in the miconazole and itraconazole groups, respectively (P = 0.0329). Adverse events occurred in 53 subjects (33 in the miconazole group and 20 in the itraconazole group). There was no statistical difference in the safety profile between miconazole and itraconazole (P = 0.0533). Thrombocytopenic purpura, although rare, occurred in one patient in the miconazole group and was considered a drug-related, severe adverse event.

Conclusion

Miconazole nitrate mucoadhesive tablets may be as effective as systemic itraconazole capsule for OC treatment. Physicians should be cautious about thrombocytopenic purpura occurring as a rare and serious adverse event of miconazole nitrate.

Trial Registration

Chinese Clinical Trial Register ChiCTR-TRC-13003935

Miconazole-loaded solid lipid nanoparticles: formulation and evaluation of a novel formula with high bioavailability and antifungal activity

Background and objective

Miconazole is a broad-spectrum antifungal drug that has poor aqueous solubility (<1 µg/mL); as a result, a reduction in its therapeutic efficacy has been reported. The aim of this study was to formulate and evaluate miconazole-loaded solid lipid nanoparticles (MN-SLNs) for oral administration to find an innovative way to alleviate the disadvantages associated with commercially available capsules.

Methods

MN-SLNs were prepared by hot homogenization/ultrasonication. The solubility of miconazole in different solid lipids was measured. The effect of process variables, such as surfactant types, homogenization and ultrasonication times, and the charge-inducing agent on the particle size, zeta potential, and encapsulation efficiency were determined. Furthermore, in vitro drug release, antifungal activity against Candida albicans, and in vivo pharmacokinetics were studied in rabbits.

Results

The MN-SLN, consisting of 1.5% miconazole, 2% Precirol ATO5, 2.5% Cremophor RH40, 0.5% Lecinol, and 0.1% Dicetylphosphate, had an average diameter of 23 nm with a 90.2% entrapment efficiency. Furthermore, the formulation of MN-SLNs enhanced the antifungal activity compared with miconazole capsules. An in vivo pharmacokinetic study revealed that the bioavailability was enhanced by >2.5-fold.

Conclusion

MN-SLN was more efficient in the treatment of candidiasis with enhanced oral bioavailability and could be a promising carrier for the oral delivery of miconazole.

Bortezomib treatment produces nocifensive behavior and changes in the expression of TRPV1, CGRP, and substance P in the rat DRG, spinal cord, and sciatic nerve

To investigate neurochemical changes associated with bortezomib-induced painful peripheral neuropathy (PN), we examined the effects of a single-dose intravenous administration of bortezomib and a well-established "chronic" schedule in a rat model of bortezomib-induced PN. The TRPV1 channel and sensory neuropeptides CGRP and substance P (SP) were studied in L4-L5 dorsal root ganglia (DRGs), spinal cord, and sciatic nerve. Behavioral measures, performed at the end of the chronic bortezomib treatment, confirmed a reduction of mechanical nociceptive threshold, whereas no difference occurred in thermal withdrawal latency. Western blot analysis showed a relative increase of TRPV1 in DRG and spinal cord after both acute and chronic bortezomib administration. Reverse transcriptase-polymerase chain reaction revealed a decrease of TRPV1 and CGRP mRNA relative levels after chronic treatment. Immunohistochemistry showed that in the DRGs, TRPV1-, CGRP-, and SP-immunoreactive neurons were mostly small- and medium-sized and the proportion of TRPV1- and CGRP-labeled neurons increased after treatment. A bortezomib-induced increase in density of TRPV1- and CGRP-immunoreactive innervation in the dorsal horn was also observed. Our findings show that bortezomib-treatment selectively affects subsets of DRG neurons likely involved in the processing of nociceptive stimuli and that neurochemical changes may contribute to development and persistence of pain in bortezomib-induced PN.

A prospective two-year assessment of miconazole resistance in Candida spp. With repeated treatment with 0.25% miconazole nitrate ointment in neonates and infants with moderate to severe diaper dermatitis complicated by cutaneous candidiasis

A petrolatum and zinc oxide-based ointment containing 0.25% miconazole nitrate is reported to be effective and well tolerated in the treatment of diaper dermatitis complicated by cutaneous candidiasis (DDCC). This prospective, multicenter, open-label, long-term, phase IV study investigated the potential resistance of Candida spp. to repeated topical use of 0.25% miconazole nitrate in infants age 15 months and younger with moderate to severe DDCC. For initial and recurring episodes of DDCC over the 2-year study period, subjects were treated with a 7-day course of 0.25% miconazole nitrate ointment (active components: miconazole nitrate 0.25%, zinc oxide 15%, and white petrolatum 81.35%) with a 7-day follow-up. Clinical and mycologic evaluations were conducted before treatment (day 0) and 7 days after treatment (day 14). Potential resistance to miconazole was defined using an arbitrary breakpoint of minimum inhibitory concentration of 2 μg/mL. There was no evidence of resistance to miconazole in Candida spp. after single or repeated treatment courses of 0.25% miconazole nitrate ointment. For the initial episode of DDCC, 83 of 168 subjects (49.4%) achieved a clinical cure, 77 (45.8%) achieved a mycologic cure, and 49 (29.2%) achieved an overall cure (clinical and mycologic). The overall cure rate for recurrent episodes of DDCC was similar to or numerically greater than rates observed for the initial episode. Treatment of DDCC with 0.25% miconazole nitrate ointment was effective and generally well tolerated. No evidence of the development of resistance to miconazole in Candida spp. was observed.

The joint in vitro action of polymyxin B and miconazole against pathogens associated with canine otitis externa from three European countries

BACKGROUND

Canine otitis externa, an inflammation of the external ear canal, can be maintained and worsened by bacterial or fungal infections. For topical treatment, combinations of anti-inflammatory and antimicrobial ingredients are mainly used.

HYPOTHESIS/OBJECTIVES

This study was conducted to elucidate the in vitro activity of polymyxin B and miconazole against clinical bacterial isolates from three European countries, to investigate possible differences in sensitivity and to assess drug interactions.

ANIMALS

Seventeen strains of Escherichia coli, 24 strains of Pseudomonas aeruginosa, 24 strains of Proteus mirabilis and 25 strains of Staphylococcus pseudintermedius from dogs with diagnosed otitis externa had been isolated in Germany, France and Italy.

METHODS

Drug activities were evaluated by minimal inhibitory concentration (MIC) and minimal bactericidal concentration. The potentiation of polymyxin B plus miconazole was calculated using the fractional inhibitory concentration index (FICI). An FICI ≤0.5 defined synergy. Furthermore, geographical variations in the FICI and MIC were assessed by statistical analysis.

RESULTS

Bacterial susceptibilities were comparable in different European countries, because there were no significant MIC and FICI variations (P > 0.05). As a single agent, polymyxin B had bactericidal activity against most E. coli and P. aeruginosa strains and, in higher concentrations, against S. pseudintermedius strains. Miconazole was bactericidal against all Staphylococcus strains. Synergy was demonstrated against strains of E. coli and P. aeruginosa (FICI = 0.25 and 0.50, respectively), whereas overall there was no interaction against S. pseudintermedius strains (FICI = 1.25). Proteus mirabilis strains were not inhibited by each of the drugs individually or by their combination.

CONCLUSIONS AND CLINICAL IMPORTANCE

In vitro synergy of polymyxin B and miconazole against E. coli and P. aeruginosa isolates indicates a rationale for applying both agents in combination to treat otitis externa when infected with these types of bacteria.

Comprehensive review in current developments of imidazole-based medicinal chemistry

Imidazole ring is an important five-membered aromatic heterocycle widely present in natural products and synthetic molecules. The unique structural feature of imidazole ring with desirable electron-rich characteristic is beneficial for imidazole derivatives to readily bind with a variety of enzymes and receptors in biological systems through diverse weak interactions, thereby exhibiting broad bioactivities. The related research and developments of imidazole-based medicinal chemistry have become a rapidly developing and increasingly active topic. Particularly, numerous imidazole-based compounds as clinical drugs have been extensively used in the clinic to treat various types of diseases with high therapeutic potency, which have shown the enormous development value. This work systematically gives a comprehensive review in current developments of imidazole-based compounds in the whole range of medicinal chemistry as anticancer, antifungal, antibacterial, antitubercular, anti-inflammatory, antineuropathic, antihypertensive, antihistaminic, antiparasitic, antiobesity, antiviral, and other medicinal agents, together with their potential applications in diagnostics and pathology. It is hoped that this review will be helpful for new thoughts in the quest for rational designs of more active and less toxic imidazole-based medicinal drugs, as well as more effective diagnostic agents and pathologic probes.

Miconazole, a pharmacological barrier to skin fungal infections

INTRODUCTION

Miconazole (MCZ) is a time-honored antifungal of the imidazole class. MCZ exerts a multipronged effect on fungi. It inhibits the cytochrome P450 complex, including the 14α-demethylase enzyme required for ergosterol biosynthesis, in fungal cell membranes. In addition, intracellular accumulation of toxic methylated sterols occurs and the synthesis of triglycerides and phospholipids is altered. Disturbances in oxidative and peroxidative enzyme activities lead to an intracellular toxic concentration of hydrogen peroxide. As a result, intracellular organelle destruction then leads to cell necrosis. Farnesol synthesis stimulated in Candida spp. prevents the yeast-to-mycelium formation. MCZ is further active against Gram-positive bacteria.

AREAS COVERED

This review aims at revisiting the MCZ antifungal activity in dermatomycoses.

EXPERT OPINION

MCZ's wide spectrum of activity appears noteworthy. The full pharmacological profile of MCZ indicates its fungistatic profile through its effect on ergosterol biosynthesis. In addition, it exhibits a fungicidal effect against a number of fungal species, due to hydrogen peroxide accumulation. MCZ is characterized by high safety, efficacy and versatility, and a unique, multifaceted nature of activity in the treatment of dermatomycoses.

Miconazole mucoadhesive tablets: a novel delivery system

Oropharyngeal candidiasis (OPC) is among the most common opportunistic infections observed in persons infected with human immunodeficiency virus. A once-daily miconazole 50 mg mucoadhesive buccal tablet (MBT) is a novel delivery system with potent in vitro activity against many Candida species, including some that may be resistant to other azoles. MBT, although more expensive, offers an effective, safe, and well-tolerated topical treatment option for OPC that is administered as a convenient once-daily dose.

Functionalization of acrylic hydrogels with alpha-, beta- or gamma-cyclodextrin modulates protein adsorption and antifungal delivery

Poly(hydroxyethyl methacrylate) (pHEMA) hydrogels were functionalized with pendant alpha-, beta- and gamma-cyclodextrins (CD) with the aim of improving the biocompatibility and increasing the ability to host drug molecules. Pendant alpha-, beta- and gamma-CDs did not affect swelling of the hydrogels but slightly decreased the water contact angle. Protein deposition was notably dependent on the nature of the CD, due to their different affinities for hydrophobic moieties of proteins. Lysozyme and albumin sorption was hindered by gamma-CD. Functionalization with beta-CD also reduced protein sorption, although less so, while alpha-CD decreased lysozyme deposition but enhanced albumin sorption compared with control pHEMA hydrogels. Loading of the hydrogels with miconazole was carried out by immersion in drug suspension followed by autoclaving. Functionalization with gamma-CD doubled the affinity of the network for the drug and resulted in the highest amount loaded (up to 170 mgg(-1)). Sustained delivery was observed for several days. Some miconazole-loaded hydrogels completely prevented Candida albicans biofilm formation as assayed in an in vitro microbiological test.

Treatment strategies for oropharyngeal candidiasis

BACKGROUND

Oropharyngeal candidiasis (OPC) is a common oral disease that may cause oral symptoms, lead to regional infection (e.g., esophageal candidiasis) and increase the risk of systemic fungal infection in the compromised host.

OBJECTIVE

Critical review of the literature of prevention and therapy.

METHODS

The literature was reviewed using PubMed, and specific keywords from the MeSH Database were used.

RESULTS/CONCLUSION

Management of OPC requires that the underlying risk factors of infection be diagnosed and managed whenever possible. Antimicrobials may be provided as topical or systemic therapy. Topical therapies may provide effective management for candidiasis in the non-compromised host and increase the control of colonization in the compromised host. Advances in prevention and management include new agents and improved mechanisms of topical drug delivery.

Miconazole revisited: new evidence of antifungal efficacy from laboratory and clinical trials

In the past 40 years imidazoles have been used extensively in medicine for their antifungal properties. All members of the azole antifungal family inhibit ergosterol biosynthesis. However, the discovery of an additional fungicidal mode of action for miconazole has drawn renewed attention to this compound. In this article we review recent evidence of mechanistic efficacy, as well as clinical trial results of miconazole in new topical formulations.

Species distribution and susceptibility to azoles of vaginal yeasts isolated prostitutes

Objective. We investigated the use of miconazole among female prostitutes in Costa Rica as well as the distribution of vaginal yeasts and the susceptibility pattern to azoles of strains obtained from this population. Our intention was to relate a frequent use of miconazole to occurrence of vaginal yeasts resistant to azoles. Methods. Vaginal samples were taken from 277 patients that have previously used azoles. Vaginal swabs were obtained for direct microscopy and culture. Yeast isolates were identified by germ tube test and assimilation pattern. Susceptibility testing was determined using a tablet diffusion method. Results. The number of clinical Candida isolates (one from each patient) was 57 (20.6%). C. albicans was the predominant species (70%), followed by C. parapsilosis (12%), C. tropicalis (5.3%), C. glabrata and C. famata (3.5% each), C. krusei, C. inconspicua and C. guilliermondii (1.7% each). The majority of vaginal Candida isolates were susceptible to ketoconazole (91%), fluconazole (96.5%), and itraconazole (98%). A lower susceptibility of some isolates to miconazole (63%) was observed as compared to the other azoles tested. Moreover, the strains, nonsusceptible to miconazole, were more often obtained from patients that have used this antifungal at least four times within the last year before taking the samples as compared to those with three or less treatments (P<.01). Conclusion. An indiscriminate use of miconazole, such as that observed among female prostitutes in Costa Rica, results in a reduced susceptibility of vaginal yeasts to miconazole but not to other azoles.

Comparison of the efficacy and safety of miconazole 50-mg mucoadhesive buccal tablets with miconazole 500-mg gel in the treatment of oropharyngeal candidiasis: a prospective, randomized, single-blind, multicenter, comparative, phase III trial in patients treated with radiotherapy for head and neck cancer

BACKGROUND

Topical antifungal treatments are recommended but rarely used as first-line therapy for oropharyngeal candidiasis (OPC) in patients with cancer. Miconazole Lauriad 50-mg mucoadhesive buccal tablet (MBT) Loramyc reportedly delivered rapid and prolonged, effective concentrations of miconazole in the mouth. The objective of the current study was to compare MBT with miconazole 500-mg oral gel (MOG) in patients with head and neck cancer.

METHODS

Two hundred eighty-two patients with head and neck cancer received a 14-day treatment of either single-dose MBT or MOG administered in 4 divided doses. The primary endpoint was clinical success at Day 14, and secondary endpoints included clinical success at Day 7, clinical cure, improvement in clinical symptoms, mycologic cure, recurrence rate, and safety.

RESULTS

The success rate was statistically not inferior (P < .0001) in the MBT population to the rate observed in the MOG group (56% vs 49%, respectively; P < .0001). After adjustment for the extent of lesions and salivary secretions, a trend toward superiority was observed in favor of MBT (P = .13), particularly among patients with multiple lesions (P = .013). Results for secondary endpoints were comparable to those observed for the primary endpoint. Compliance with MBT was excellent, and >80% of patients completed treatment. Both treatments were safe.

CONCLUSIONS

The success rate of MBT Loramyc was significantly not inferior to that of MOG in the treatment of cancer patients with OPC; and, after adjusting for prognostic variables, it was more effective than MOG. MBT was well tolerated and, thus, may be recommended as first-line treatment in cancer patients who have OPC as an alternative to systemic antifungal agents. Society.

Advances in topical and systemic antifungals

Topical antifungal agents are generally used for the treatment of superficial fungal infections unless the infection is widespread, involves an extensive area, or is resistant to initial therapy. Systemic antifungals are often reserved for the treatment of onychomycosis, tinea capitis, superficial and systemic candidiasis, and prophylaxis and treatment of invasive fungal infections. With the development of resistant fungi strains and the increased incidence of life-threatening invasive fungal infections in immunocompromised patients, some previously effective traditional antifungal agents are subject to limitations including multidrug interactions, severe adverse effects, and their fungistatic mechanism of actions. Several new antifungal agents have demonstrated significant therapeutic benefits and have broadened clinicians' choices in the treatment of superficial and systemic invasive fungal infections.