VT-1161 protects mice against oropharyngeal candidiasis caused by fluconazole-susceptible and -resistant Candida albicans

Oteseconazole for the Treatment of Recurrent Vulvovaginal Candidiasis: A Drug Review

OBJECTIVE

The objective of the study is to describe and analyze the pharmacodynamics and pharmacokinetics of oteseconazole as well as the clinical evidence supporting the efficacy of oteseconazole in treating recurrent vulvovaginal candidiasis (RVVC).

DATA SOURCES

A literature search was conducted using MEDLINE and EMBASE databases (2015-June 2023). Search terms included "oteseconazole" OR "VT-1161" or "VIVJOA" AND "RVVC" or "recurrent vulvovaginal candidiasis" or "vulvovaginal candidiasis." Conference abstracts, bibliographies, clinical trials, and drug monographs were included for review.

STUDY SELECTION AND DATA EXTRACTION

Relevant studies in English and clinical trials conducted in humans were reviewed.

DATA SYNTHESIS

Oteseconazole is approved for the treatment of RVVC. In 2 identical phase III studies, oteseconazole was superior to placebo through 48 weeks for preventing recurrence of RVVC (6.7% vs 42.8%, P < 0.001 and 3.9% vs 39.4%, P < 0.001). In the only phase III trial comparing oteseconazole against active drug, oteseconazole was well tolerated and exhibited noninferiority to fluconazole in acute treatment and superiority to placebo for prevention maintenance through 50 weeks (5.1% vs 42.2%, P < 0.001).

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE IN COMPARISON TO EXISTING AGENTS

This review describes the use of oteseconazole for the treatment of RVVC as compared with fluconazole. Oteseconazole is an effective treatment option for common pathogens causing vulvovaginal candidiasis, including Candida and fluconazole-resistant Candida.

CONCLUSIONS

Oteseconazole is an effective and safe treatment option for the management of RVVC though current research lacks comparison with established maintenance regimens. Additional research is needed to ascertain the placement of oteseconazole in the treatment of RVVC.

Novel antifungals and treatment approaches to tackle resistance and improve outcomes of invasive fungal disease

SUMMARYFungal infections are on the rise, driven by a growing population at risk and climate change. Currently available antifungals include only five classes, and their utility and efficacy in antifungal treatment are limited by one or more of innate or acquired resistance in some fungi, poor penetration into "sequestered" sites, and agent-specific side effect which require frequent patient reassessment and monitoring. Agents with novel mechanisms, favorable pharmacokinetic (PK) profiles including good oral bioavailability, and fungicidal mechanism(s) are urgently needed. Here, we provide a comprehensive review of novel antifungal agents, with both improved known mechanisms of actions and new antifungal classes, currently in clinical development for treating invasive yeast, mold (filamentous fungi), Pneumocystis jirovecii infections, and dimorphic fungi (endemic mycoses). We further focus on inhaled antifungals and the role of immunotherapy in tackling fungal infections, and the specific PK/pharmacodynamic profiles, tissue distributions as well as drug-drug interactions of novel antifungals. Finally, we review antifungal resistance mechanisms, the role of use of antifungal pesticides in agriculture as drivers of drug resistance, and detail detection methods for antifungal resistance.

Host antimicrobial peptide S100A12 disrupts the fungal membrane by direct binding and inhibits growth and biofilm formation of Fusarium species

Fungal keratitis is the foremost cause of corneal infections worldwide, of which Fusariumspp. is the common etiological agent that causes loss of vision and warrants surgical intervention. An increase in resistance to the available drugs along with severe side effects of the existing antifungals demands for new effective antimycotics. Here, we demonstrate that antimicrobial peptide S100A12 directly binds to the phospholipids of the fungal membrane, disrupts the structural integrity, and induces generation of reactive oxygen species in fungus. In addition, it inhibits biofilm formation by Fusariumspp. and exhibits antifungal property against Fusariumspp. both in vitro and in vivo. Taken together, our results delve into specific effect of S100A12 against Fusariumspp. with an aim to investigate new antifungal compounds to combat fungal keratitis.

Perspective on receptor-associated immune response to Candida albicans single and mixed infections: Implications for therapeutics in oropharyngeal candidiasis

Oropharyngeal candidiasis (OPC), commonly known as 'thrush', is an oral infection that usually dismantles oral mucosal integrity and malfunctions local innate and adaptive immunities in compromised individuals. The major pathogen responsible for the occurrence and progression of OPC is the dimorphic opportunistic commensal Candida albicans. However, the incidence induced by non-albicans Candida species including C. glabrata, C. tropicalis, C. dubliniensis, C. parapsilosis, and C. krusei are increasing in company with several oral bacteria, such as Streptococcus mutans, S. gordonii, S. epidermidis, and S. aureus. In this review, the microbiological and infection features of C. albicans and its co-contributors in the pathogenesis of OPC are outlined. Since the invasion and concomitant immune response lie firstly on the recognition of oral pathogens through diverse cellular surface receptors, we subsequently emphasize the roles of epidermal growth factor receptor, ephrin-type receptor 2, human epidermal growth factor receptor 2, and aryl hydrocarbon receptor located on oral epithelial cells to delineate the underlying mechanism by which host immune recognition to oral pathogens is mediated. Based on these observations, the therapeutic approaches to OPC comprising conventional and non-conventional antifungal agents, fungal vaccines, cytokine and antibody therapies, and antimicrobial peptide therapy are finally overviewed. In the face of newly emerging life-threatening microbes (C. auris and SARS-CoV-2), risks (biofilm formation and interconnected translocation among diverse organs), and complicated clinical settings (HIV and oropharyngeal cancer), the research on OPC is still a challenging task.

Oteseconazole: a long-awaited diversification of the antifungal arsenal to manage recurrent vulvovaginal candidiasis (RVVC)

INTRODUCTION

Recurrent vulvovaginal candidiasis (RVVC) affects women worldwide and has far-reaching implications for a patient's quality of life. For decades, maintenance treatment using the azole antifungal fluconazole was the preferred treatment. Although efficient in controlling the symptoms, the development of azole resistance and high rates of recurrence after therapy cessation have emerged as significant limitations. Nevertheless, persistent efforts have delivered novel treatment options. Oteseconazole (VT-1161), marketed as VIVJOA, is an oral, tetrazole antifungal with unprecedented specificity toward the fungal lanosterol 14α-demethylase.

AREAS COVERED

We reviewed literature data on oteseconazole with a focus on the management of RVVC.

EXPERT OPINION

Therapeutic options for RVVC are limited, and novel, innovative approaches are needed to treat this debilitating condition. These therapies need to be well-tolerated and prevent RVVC recurrence. The available clinical data show excellent safety and efficacy, with an unprecedentedly low recurrence rate. However, we believe health-care providers should be mindful to monitor for the development of resistance, as this may result in treatment failure. Further, the availability and cost may, like for most novel drugs, affect the widespread clinical implementation of VIVJOA. Altogether, we are convinced that VIVJOA is a significant advance in RVVC management.

Anti-Candida albicans Activity of Ononin and Other Secondary Metabolites from Platonia Insignis MART

Candida albicans is a human pathogen that is part of the healthy microbiome. However, it is often associated with opportunistic fungal infections. The treatment of these infections is challenging because prolonged exposure to antifungal drugs can culminate in fungal resistance during therapy, and there is a limited number of available drugs. Therefore, this study investigated the antifungal activity of ononin by in silico and in vitro assays, and in Tenebrio molitor as an alternative in vivo model of infection caused by C. albicans. Ononin is an isoflavone glycoside derived from formononetin that has various biological activities. According in silico evaluation, ononin showed the best electron affinity in molecular docking with CaCYP51, with a binding free energy of -10.89 kcal/mol, superior to that of the antifungal drugs fluconazole and posaconazole. The ononin + CaCYP51 complex formed hydrogen bonds with Tyr132, Ser378, Phe380, and Met508, as well as hydrophobic connections with Tyr118, Leu121, Phe126, Leu131, Ile304, and Leu309, and interactions with the heme group. Ononin exerted anti-Candida albicans activity, with MIC between 3.9 and 7.8 µg/mL, and inhibited young and mature biofilms, with a reduction in cell density and metabolic activity of 50 to 80%. The compound was not cytotoxic to sheep red blood cells at concentrations up to 1000 µg/mL. Larvae of the mealworm T. molitor were used as an alternative in vivo model of C. albicans infection. Ononin was able to prolong larval survival at concentrations of 0.5, 1, and 5 mg/kg, and was not toxic up to a concentration of 20 mg/kg. Moreover, ononin reduced the fungal charge in treated animals. In conclusion, our results suggest that ononin has anti-Candida albicans activity and is a potential candidate for the development of new therapeutic alternatives.

Development and research progress of anti-drug resistant fungal drugs

With the widespread use of immunosuppressive agents and the increase in patients with severe infections, the incidence of fungal infections worldwide has increased year by year. The fungal pathogens Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus cause a total of more than 1 million deaths each year. Long-term use of antifungal drugs can easily lead to fungal resistance, and the prevalence of drug-resistant fungi is a major global health challenge. In order to effectively control global fungal infections, there is an urgent need for new drugs that can exert effective antifungal activity and overcome drug resistance. We must promote the discovery of new antifungal targets and drugs, and find effective ways to control drug-resistant fungi through different ways, so as to reduce the threat of drug-resistant fungi to human life, health and safety. In the past few years, certain progress has been made in the research and development of antifungal drugs. In addition to summarizing some of the antifungal drugs currently approved by the FDA, this review also focuses on potential antifungal drugs, the repositioned drugs, and drugs that can treat drug-resistant bacteria and fungal infections, and provide new ideas for the development of antifungal drugs in the future.

Pharmacodynamics, Mechanisms of Action and Resistance, and Spectrum of Activity of New Antifungal Agents

Several new antifungals are currently in late-stage development, including those with novel pharmacodynamics/mechanisms of action that represent new antifungal classes (manogepix, olorofim, ATI-2307, GR-2397). Others include new agents within established classes or with mechanisms of action similar to clinically available antifungals (ibrexafungerp, rezafungin, oteseconazole, opelconazole, MAT2203) that have been modified in order to improve certain characteristics, including enhanced pharmacokinetics and greater specificity for fungal targets. Many of the antifungals under development also have activity against Candida and Aspergillus strains that have reduced susceptibility or acquired resistance to azoles and echinocandins, whereas others demonstrate activity against species that are intrinsically resistant to most clinically available antifungals. The tolerability and drug–drug interaction profiles of these new agents also appear to be promising, although the number of human subjects that have been exposed to many of these agents remains relatively small. Overall, these agents have the potential for expanding our antifungal armamentarium and improving clinical outcomes in patients with invasive mycoses.

Drug Resistance and Novel Therapeutic Approaches in Invasive Candidiasis

Candida species are the leading cause of invasive fungal infections worldwide and are associated with acute mortality rates of ~50%. Mortality rates are further augmented in the context of host immunosuppression and infection with drug-resistant Candida species. In this review, we outline antifungal drugs already in clinical use for invasive candidiasis and candidaemia, their targets and mechanisms of resistance in clinically relevant Candida species, encompassing not only classical resistance, but also heteroresistance and tolerance. We describe novel antifungal agents and targets in pre-clinical and clinical development, including their spectrum of activity, antifungal target, clinical trial data and potential in treatment of drug-resistant Candida. Lastly, we discuss the use of combination therapy between conventional and repurposed agents as a potential strategy to combat the threat of emerging resistance in Candida.

Pathogenesis and virulence of Candida albicans

Candida albicans is a commensal yeast fungus of the human oral, gastrointestinal, and genital mucosal surfaces, and skin. Antibiotic-induced dysbiosis, iatrogenic immunosuppression, and/or medical interventions that impair the integrity of the mucocutaneous barrier and/or perturb protective host defense mechanisms enable C. albicans to become an opportunistic pathogen and cause debilitating mucocutaneous disease and/or life-threatening systemic infections. In this review, we synthesize our current knowledge of the tissue-specific determinants of C. albicans pathogenicity and host immune defense mechanisms.

Advances in anti-fungal therapies

Anti-fungal therapies remain sub-optimal, and resistant pathogens are increasing. New therapies are desperately needed, especially options that are less toxic than most of the currently available selection. In this review, I will discuss anti-fungal therapies that are in at least phase I human trials. These include VT-1161 and VT-1598, modified azoles with a tetrazole metal-binding group; the echinocandin rezafugin; the novel β-1,3-d-glucan synthase inhibitor ibrexafungerp; fosmanogepix, a novel anti-fungal targeting Gwt1; the arylamidine T-2307; the dihydroorotate inhibitor olorofim; and the cyclic hexapeptide ASP2397. The available data including spectrum of activity, toxicity and stage of clinical development will be discussed for each of these so clinicians are aware of promising anti-fungal agents with a strong likelihood of clinical availability in the next 5–7 years.

How urgent is the need for new antifungals?

Introduction: Invasive fungal infection carries a high morbidity, mortality and economic cost. In recent times, a rising incidence of fungal infection and antifungal resistance is occurring which has prompted the development of novel antifungal agents.Areas covered:In this perspective, the authors describe the current status of registered antifungals and their limitations in the treatment of invasive fungal infection. They also go on to describe the new antifungal agents that are in the clinical stage of development and how they might be best utilized in patient care in the future.Expert opinion: The antifungal drug development pipeline has responded to a growing need for new agents to effectively treat fungal disease without concomitant toxicity or issues with drug tolerance. Olorofim (F901318), ibrexafungerp (SCY-078), fosmanogepix (APX001), rezafungin (CD101), oteseconazole (VT-1161), encochleated amphotericin B (MAT2203), nikkomycin Z (NikZ) and ATI-2307 are all in the clinical stage of development and offer great promise in offering clinicians better agents to treat these difficult infections.

In vitro activities of the tetrazole VT-1161 compared with itraconazole and fluconazole against Cryptococcus and non-albicans Candida species

Recently, Cryptococcus and non-albicans Candida (NAC) have emerged as health-threatening pathogens for clinical fungal infections. Due to their increased resistance to existing antifungal drugs, novel antifungals are urgently needed. In this study, we evaluated the antifungal effect of VT-1161 and its comparators itraconazole and fluconazole against common fluconazole-sensitive or -resistant Cryptococcus and NAC strains. The tested strains were obtained from Chinese patients by the Invasive Fungal Infection Group within the past 2 years. The minimum inhibitory concentrations (MICs) of VT-1161 and other triazoles were measured according to the Clinical and Laboratory Standards Institute (CLSI) M27-Ed4 guidelines. We found that VT-1161 exhibited strong in vitro activity against Cryptococcus spp.. VT-1161 (geometric mean MIC = 0.024 μg/mL) was 21.7-fold and 104.5-fold more potent than itraconazole and fluconazole, respectively. Against the seven Cryptococcus neoformans isolates with higher fluconazole MICs (≥8 μg/mL based on the MIC₉₀ value of this azole), VT-1161 maintained potent activities, with MICs ranging between 0.031 and 0.5 μg/mL. For NAC spp., VT-1161 (geometric mean MIC = 0.099 μg/mL) was 6.0-fold and 11.4-fold more effective than itraconazole and fluconazole, respectively. There is a positive correlation of the MICs between VT-1161 and itraconazole/fluconazole. The MIC values of VT-1161 against Candida glabrata and Candida tropicalis were significantly lower than those of fluconazole, whereas for Candida parapsilosis the differences in the MIC values between VT-1161 and fluconazole were not statistically significant. The results showed that tetrazole VT-1161 might be a promising candidate for treating Cryptococcus and NAC infections.

Aberrant type 1 immunity drives susceptibility to mucosal fungal infections

Human monogenic disorders have revealed the critical contribution of type 17 responses in mucosal fungal surveillance. We unexpectedly found that in certain settings, enhanced type 1 immunity rather than defective type 17 responses can promote mucosal fungal infection susceptibility. Notably, in mice and humans with AIRE deficiency, an autoimmune disease characterized by selective susceptibility to mucosal but not systemic fungal infection, mucosal type 17 responses are intact while type 1 responses are exacerbated. These responses promote aberrant interferon-γ (IFN-γ)- and signal transducer and activator of transcription 1 (STAT1)-dependent epithelial barrier defects as well as mucosal fungal infection susceptibility. Concordantly, genetic and pharmacologic inhibition of IFN-γ or Janus kinase (JAK)-STAT signaling ameliorates mucosal fungal disease. Thus, we identify aberrant T cell-dependent, type 1 mucosal inflammation as a critical tissue-specific pathogenic mechanism that promotes mucosal fungal infection susceptibility in mice and humans.

Antimicrobial and antibiofilm activity of the EeCentrocin 1 derived peptide EC1-17KV via membrane disruption

Background

The antibiotic resistance and biofilm formation of pathogenic microbes exacerbate the difficulties of anti-infection therapy in the clinic. The structural modification of antimicrobial peptides (AMP) is an effective strategy to develop novel anti-infective agents.

Method

Seventeen amino acids (AA) in the longer chain of EeCentrocin 1 (from the edible sea-urchin Echinus esculentus) were truncated and underwent further modification. To produce lead peptides with low toxicity and high efficacy, the antimicrobial activity or cytotoxicity of peptides was evaluated against various multidrug-resistant bacteria/fungi or mammalian cells in vivo/ in vitro. In addition, the stability and modes of action of the lead peptide were investigated.

Findings

EC1-17KV displayed potent activity and an expanded antimicrobial spectrum, especially against drug-resistant gram-negative bacteria and fungi, attributable to its enhanced amphiphilicity and net charge. In addition, it exhibits bactericidal/fungicidal activity and effectively increased the animal survival rate and mitigated the histopathological damage induced by multidrug-resistant P. aeruginosa or C. albicans in infected mice or G. mellonella. Moreover, EC1-17KV had a poor ability to induce resistance in bacteria and fungi and exhibited desirable high-salt/high-temperature tolerance properties. In bacteria, EC1-17KV promoted divalent cation release to damage bacterial membrane integrity. In fungi, it changed C. albicans membrane fluidity to increase membrane permeabilization or reduced hyphal formation to suppress biofilm formation.

Interpretation

EC1-17KV is a promising lead peptide for the development of antimicrobial agents against antibiotic resistant bacteria and fungi.

Funding

This work was funded by the National Natural Science Foundation of China (No. 81673483, 81803591); National Science and Technology Major Project Foundation of China (2019ZX09721001-004-005); National Key Research and Development Program of China (2018YFA0902000); "Double First-Class" University project (CPU2018GF/GY16); Natural Science Foundation of Jiangsu Province of China (No. BK20180563); and A Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.

New and Promising Chemotherapeutics for Emerging Infections Involving Drug-resistant Non-albicans Candida Species

Fungal infections are a veritable public health problem worldwide. The increasing number of patient populations at risk (e.g. transplanted individuals, cancer patients, and HIV-infected people), as well as the use of antifungal agents for prophylaxis in medicine, have favored the emergence of previously rare or newly identified fungal species. Indeed, novel antifungal resistance patterns have been observed, including environmental sources and the emergence of simultaneous resistance to different antifungal classes, especially in Candida spp., which are known for the multidrug-resistance (MDR) profile. In order to circumvent this alarming scenario, the international researchers' community is engaged in discovering new, potent, and promising compounds to be used in a near future to treat resistant fungal infections in hospital settings on a global scale. In this context, many compounds with antifungal action from both natural and synthetic sources are currently under clinical development, including those that target either ergosterol or β(1,3)-D-glucan, presenting clear evidence of pharmacologic/pharmacokinetic advantages over currently available drugs against these two well-known fungal target structures. Among these are the tetrazoles VT-1129, VT-1161, and VT-1598, the echinocandin CD101, and the glucan synthase inhibitor SCY-078. In this review, we compiled the most recent antifungal compounds that are currently in clinical trials of development and described the potential outcomes against emerging and rare Candida species, with a focus on C. auris, C. dubliniensis, C. glabrata, C. guilliermondii, C. haemulonii, and C. rugosa. In addition to possibly overcoming the limitations of currently available antifungals, new investigational chemical agents that can enhance the classic antifungal activity, thereby reversing previously resistant phenotypes, were also highlighted. While novel and increasingly MDR non-albicans Candida species continue to emerge worldwide, novel strategies for rapid identification and treatment are needed to combat these life-threatening opportunistic fungal infections.

VT-1598 inhibits the in vitro growth of mucosal Candida strains and protects against fluconazole-susceptible and -resistant oral candidiasis in IL-17 signalling-deficient mice

Background

Chronic mucocutaneous candidiasis (CMC) treatment often induces drug resistance, posing long-term challenges. A novel broad-spectrum fungal CYP51 inhibitor, VT-1598, specifically targets fungal CYP51, but not human CYP enzymes.

Objectives

To determine the efficacy of VT-1598 in the treatment of oral Candida infection caused by fluconazole-susceptible and -resistant clinical isolates.

Methods

The MICs of VT-1598 and fluconazole for 28 Candida isolates recovered from patients with inherited CMC were determined using CLSI M27-A3 and M27-S4 guidelines. Plasma and tongue VT-1598 or fluconazole concentrations were measured in mice following oral administration to determine tissue distribution. Tongue fungal load was determined in IL-17 signalling-deficient Act1-/- mice following sublingual Candida albicans infection and oral treatment with fluconazole or VT-1598.

Results

Among the 28 Candida isolates, 10 (36%) had fluconazole MICs of ≥4 mg/L, whereas VT-1598 demonstrated potent in vitro activity against all isolates (MIC90, 0.125 mg/L). After oral administration, VT-1598 levels in mouse plasma and tongue were significantly greater than those of fluconazole. In vivo, VT-1598 exhibited significant efficacy against fluconazole-susceptible and -resistant C. albicans, even at low drug doses. Furthermore, after a 10 day washout period, tongue fungal burdens in fluconazole-treated mice returned to vehicle control levels, whereas, in contrast, they were undetectable in mice treated with VT-1598.

Conclusions

VT-1598 effectively controls in vitro growth of mucosally derived Candida clinical isolates, including fluconazole-resistant strains. In vivo, VT-1598 eliminates C. albicans, even after a long washout period or at low doses. Therefore, VT-1598 is a promising drug candidate that may significantly improve treatment options for CMC patients.

The Fungal CYP51s: Their Functions, Structures, Related Drug Resistance, and Inhibitors

CYP51 (Erg11) belongs to the cytochrome P450 monooxygenase (CYP) superfamily and mediates a crucial step of the synthesis of ergosterol, which is a fungal-specific sterol. It is also the target of azole drugs in clinical practice. In recent years, researches on fungal CYP51 have stepped into a new stage attributing to the discovery of crystal structures of the homologs in Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus. This review summarizes the functions, structures of fungal CYP51 proteins, and the inhibitors targeting these homologs. In particular, several drug-resistant mechanisms associated with the fungal CYP51s are introduced. The sequences and crystal structures of CYP51 proteins in different fungal species are also compared. These will provide new insights for the advancement of research on antifungal agents.

Lessons from primary immunodeficiencies: Autoimmune regulator and autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy

The discovery of the autoimmune regulator (AIRE) protein and the delineation of its critical contributions in the establishment of central immune tolerance has significantly expanded our understanding of the immunological mechanisms that protect from the development of autoimmune disease. The parallel identification and characterization of patient cohorts with the monogenic disorder autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), which is typically caused by biallelic AIRE mutations, has underscored the critical contribution of AIRE in fungal immune surveillance at mucosal surfaces and in prevention of multiorgan autoimmunity in humans. In this review, we synthesize the current clinical, genetic, molecular and immunological knowledge derived from basic studies in Aire-deficient animals and from APECED patient cohorts. We also outline major advances and research endeavors that show promise for informing improved diagnostic and therapeutic approaches for patients with APECED.

Treatment of Invasive Candidiasis: A Narrative Review

Invasive candidiasis occurs frequently in hospitalized patients, and is associated with high mortality rates due to delays in recognition and initiation of appropriate antifungals. Management of invasive candidiasis must take into account multiple host, pathogen, and drug-related factors, including the site of infection, host immune status, severity of sepsis, resistance and tolerance to antifungal agents, biofilm formation, and pharmacokinetic/pharmacodynamic considerations. Recent treatment directives have been shaped by the widespread introduction of echinocandins, highly potent and safe antifungals, into clinical use, as well as important changes in drug susceptibility patterns and the emergence of known and novel drug-resistant Candida species. Advances in molecular diagnostics have the potential to guide early targeted treatment of high-risk patients.

Current treatment options for vulvovaginal candidiasis caused by azole-resistant Candida species

INTRODUCTION

Clinicians are increasingly challenged by patients with refractory vulvovaginal candidiasis (VVC) caused by azole-resistant Candida species. Fluconazole resistant C.albicans is a growing and perplexing problem following years of indiscriminate drug prescription and unnecessary drug exposure and for which there are few therapeutic alternatives. Regrettably, although the azole class of drugs has expanded, new classes of antifungal drugs have not been forthcoming, limiting effective treatment options in patients with azole resistant Candida vaginitis.

AREAS COVERED

This review covers published data on epidemiology, pathophysiology and treatment options for women with azole-resistant refractory VVC.

EXPERT OPINION

Fluconazole resistant C.albicans adds to the challenge of azole resistant non-albicans Candida spp. Both issues follow years of indiscriminate drug prescription and unnecessary fluconazole exposure. Although an understanding of azole resistance in yeast has been established, this knowledge has not translated into useful therapeutic advantage. Treatment options for such women with refractory symptoms are extremely limited. New therapeutic options and strategies are urgently needed to meet this challenge of azole drug resistance.

Methodologies for in vitro and in vivo evaluation of efficacy of antifungal and antibiofilm agents and surface coatings against fungal biofilms

Unlike superficial fungal infections of the skin and nails, which are the most common fungal diseases in humans, invasive fungal infections carry high morbidity and mortality, particularly those associated with biofilm formation on indwelling medical devices. Therapeutic management of these complex diseases is often complicated by the rise in resistance to the commonly used antifungal agents. Therefore, the availability of accurate susceptibility testing methods for determining antifungal resistance, as well as discovery of novel antifungal and antibiofilm agents, are key priorities in medical mycology research. To direct advancements in this field, here we present an overview of the methods currently available for determining (i) the susceptibility or resistance of fungal isolates or biofilms to antifungal or antibiofilm compounds and compound combinations; (ii) the in vivo efficacy of antifungal and antibiofilm compounds and compound combinations; and (iii) the in vitro and in vivo performance of anti-infective coatings and materials to prevent fungal biofilm-based infections.