Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 180
Filter
1.
Article in English | MEDLINE | ID: mdl-33558297

ABSTRACT

BACKGROUND. Candida auris has demonstrated the ability to colonize the skin of hospitalized patients, possibly contributing to nosocomial spread. OBJECTIVE. The objective was to determine whether two novel transdermal agents could clear skin colonization established by C. auris METHODS. A murine skin colonization model was first optimized and then used to test fungal burden reduction following treatment with 1% terbinafine or 1% clotrimazole in a proprietary Advanced Penetration Technology formulation (APT™). RESULTS. Both treatments significantly reduced fungal burden compared to control groups. CONCLUSION. These novel agents show promise as a topical means of preventing skin colonization by C. auris.

2.
BJOG ; 129(3): 412-420, 2022 02.
Article in English | MEDLINE | ID: mdl-34676663

ABSTRACT

OBJECTIVE: To evaluate the efficacy and safety of ibrexafungerp versus placebo for acute vulvovaginal candidiasis (VVC) treatment. DESIGN: Global phase 3, randomised, placebo-controlled superiority study. SETTING: Study sites in the USA (n = 19) and Bulgaria (n = 18). POPULATION: Female patients aged ≥12 years with acute VVC and a vulvovaginal signs and symptoms (VSS) score ≥4 at baseline. METHODS: Patients were randomly assigned 2:1 to ibrexafungerp (300 mg twice for 1 day) or placebo. MAIN OUTCOME MEASURES: The primary endpoint was the percentage of patients with a clinical cure (VSS = 0) at the test-of-cure visit (day 11 ± 3). Secondary endpoints included percentages of patients with mycological eradication, clinical cure and mycological eradication (overall success), clinical improvement (VSS ≤1) at test-of-cure visit, and complete resolution of symptoms at follow-up visit (day 25 ± 4). RESULTS: At the test-of-cure visit, patients receiving ibrexafungerp had significantly higher rates of clinical cure (63.3% [119/188] versus 44.0% [37/84]; P = 0.007), mycological eradication (58.5% [110/188] versus 29.8% [25/84]; P < 0.001), overall success (46.1% [82/188] versus 28.4% [23/84]; P = 0.022) and clinical improvement (72.3% [136/188] versus 54.8% [46/84]; P = 0.01) versus those receiving placebo. Symptom resolution was sustained and further increased with ibrexafungerp (73.9%) versus placebo (52.4%) at follow-up (P = 0.001). Ibrexafungerp was generally well tolerated. Adverse events were primarily gastrointestinal and were mild to moderate in severity. CONCLUSIONS: Ibrexafungerp demonstrated statistical superiority over placebo for the primary and secondary endpoints. Ibrexafungerp is a promising novel, well-tolerated and effective oral 1-day treatment for acute VVC. TWEETABLE ABSTRACT: Ibrexafungerp is statistically superior to placebo for the treatment of vulvovaginal candidiasis.


Subject(s)
Antifungal Agents/administration & dosage , Candidiasis, Vulvovaginal/drug therapy , Glycosides/administration & dosage , Triterpenes/administration & dosage , Acute Disease , Administration, Oral , Adolescent , Adult , Aged , Double-Blind Method , Female , Humans , Middle Aged , Treatment Outcome , Young Adult
4.
Antimicrob Agents Chemother ; 64(10)2020 09 21.
Article in English | MEDLINE | ID: mdl-32718958

ABSTRACT

Candida auris has been shown to have a high risk of skin colonization in hospitalized patients, possibly contributing to nosocomial spread. In a guinea pig skin model, animals were evaluated for clinical appearance, tissue fungal burden, histology, and pharmacokinetics. Oral dosing with 10 mg/kg ibrexafungerp (IBX) reduced the severity of lesions and significantly reduced the C. auris fungal burden in infected animals compared with untreated controls. This indicates promise for use of IBX in controlling skin infection and colonization of hospitalized patients.


Subject(s)
Candida , Triterpenes , Animals , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Glycosides , Guinea Pigs , Humans
5.
Antimicrob Agents Chemother ; 63(12)2019 09 09.
Article in English | MEDLINE | ID: mdl-31570395

ABSTRACT

Ibrexafungerp (formerly SCY-078), a novel glucan synthase inhibitor with oral availability, was evaluated for activity against Candida glabrata Susceptibility of clinical strains to Ibrexafungerp was determined by microdilution and time kill assays. The MIC range against wild type strains was 1-2 µg/mL. IBX was also active against the majority of echinocandin-resistant strains. Time kill studies showed a 4 to 6-log reduction in growth at concentrations of 0.25 to 4 µg/ml at 24 and 48 hr.

6.
Clin Microbiol Infect ; 25(7): 792-798, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30965100

ABSTRACT

BACKGROUND: Recently there has been an increase in Candida infections worldwide. A handful of species in the genus Candida are opportunistic pathogens and have been known to cause infections in immunocompromised or otherwise impaired hosts. These infections can be superficial, affecting the skin or mucous membrane, or invasive, which can be life-threatening. Azoles and echinocandins are antifungal drugs used globally to treat Candida infections. However, resistance to these antifungal drugs has increased in many of the Candida species, and the effects this has in the clinical setting can be seen. OBJECTIVES: Here, we discuss the mechanisms that Candida albicans, Candida dubliniensis, Candida glabrata, Candida parapsilosis, Candida tropicalis and Candida auris are implementing to increase resistance to azoles and echinocandins, and how they are affecting clinical, or hospital, settings worldwide. SOURCES: Different studies and papers describing the mechanisms of antifungal drugs and Candida species evolution to becoming resistant to these drugs were looked at for this review. CONTENT: We discuss the mechanisms that azoles and echinocandins use against Candida species to treat infections, as well as the evolution of these fungi to become resistant to these drugs, and the effect this has in the clinical settings around the globe. IMPLICATIONS: Increased resistance to azoles and echinocandins by Candida species is an increasingly serious problem in clinical settings worldwide. Understanding the mechanisms used against antifungal drugs is imperative for patient treatment.


Subject(s)
Antifungal Agents/pharmacology , Candida/drug effects , Drug Resistance, Multiple, Fungal , Azoles/pharmacology , Candida albicans/drug effects , Candida glabrata/drug effects , Echinocandins/pharmacology , Humans , Microbial Sensitivity Tests
7.
Article in English | MEDLINE | ID: mdl-30885896

ABSTRACT

Ibrexafungerp (IBX) (formerly SCY-078) is a novel glucan synthase inhibitor whose oral availability is being evaluated for efficacy against vulvovaginal candidiasis (VVC). Bioavailability and in vitro activity are important efficacy indicators, but accepted susceptibility methods do not always accurately predict activity in an acidic environment, such as the vagina. Studies were 3-fold, as follows: (i) pharmacokinetic study following oral administration in a murine model; (ii) susceptibility testing of isolates from a phase 2 VVC clinical trial by CLSI M27-A4 methodology; and (iii) susceptibility testing of Candida albicans and Candida glabrata isolates obtained from this trial group in RPMI 1640 adjusted to 3 different pH values, 7.0, 5.72, and 4.5, compared to susceptibility testing for micafungin and fluconazole. IBX readily accumulated in vaginal tissues and secretions following oral administration. Potent in vitro activity was demonstrated against Candida strains obtained at baseline and end of study visits. Moreover, the geometric mean (GM) values for IBX at pH 4.5 were dramatically lower than those at pH 7.0 and 5.72. The MIC90 values of micafungin remained the same regardless of pH value, while those of fluconazole tended to increase with lower pH values. IBX is able to reach target tissues following oral administration at pharmacologically meaningful levels. IBX demonstrated potent in vitro activity, with no development of resistance, following repeated exposure over the course of the clinical trial. Importantly, activity of IBX in an acidic medium suggests a therapeutic advantage of this novel antifungal in the treatment of vaginal Candida infections.


Subject(s)
Antifungal Agents/pharmacology , Candida/drug effects , Glycosides/pharmacology , Triterpenes/pharmacology , Vulvovaginitis/drug therapy , Vulvovaginitis/microbiology , Animals , Candida albicans/drug effects , Candida glabrata/drug effects , Drug Resistance, Fungal , Female , Hydrogen-Ion Concentration , Mice , Microbial Sensitivity Tests
8.
Article in English | MEDLINE | ID: mdl-29866870

ABSTRACT

Central-line-associated bloodstream infections are increasingly recognized to be associated with intraluminal microbial biofilms, and effective measures for the prevention and treatment of bloodstream infections remain lacking. This report evaluates a new commercially developed antimicrobial catheter lock solution (ACL), containing trimethoprim (5 mg/ml), ethanol (25%), and calcium EDTA (Ca-EDTA) (3%), for activity against bacterial and fungal biofilms, using in vitro and in vivo (rabbit) catheter biofilm models. Biofilms were formed by bacterial (seven different species, including vancomycin-resistant Enterococcus [VRE]) or fungal (Candida albicans) species on catheter materials. Biofilm formation was evaluated by quantitative culture (CFU) and scanning electron microscopy (SEM). Treatment with ACL inhibited the growth of adhesion-phase biofilms in vitro after 60 min (VRE) or 15 min (all others), while mature biofilms were completely inhibited after exposure for 2 or 4 h, compared to control. Similar results were observed for drug-resistant bacteria. Compared to the heparinized saline controls, ACL lock therapy significantly reduced the catheter bacterial (3.49 ± 0.75 versus 0.03 ± 0.06 log CFU/catheter; P = 0.016) and fungal (2.48 ± 1.60 versus 0.55 ± 1.19 log CFU/catheter segment; P = 0.013) burdens in the catheterized rabbit model. SEM also demonstrated eradication of bacterial and fungal biofilms in vivo on catheters exposed to ACL, while vigorous biofilms were observed on untreated control catheters. Our results demonstrated that ACL was efficacious against both adhesion-phase and mature biofilms formed by bacteria and fungi in vitro and in vivo.


Subject(s)
Antifungal Agents/pharmacology , Bacteria/drug effects , Biofilms/drug effects , Anti-Bacterial Agents/pharmacology , Candida albicans/drug effects , Enterococcus/drug effects , Microscopy, Electron, Scanning
9.
Article in English | MEDLINE | ID: mdl-29610204

ABSTRACT

Invasive aspergillosis remains a major cause of death among the immunocompromised population and those receiving long-term immunosuppressive therapy. In light of increased azole resistance, variable outcomes with existing echinocandin monotherapy and combination therapy, and persistent high mortality rates, new antifungal agents for the treatment of invasive aspergillosis are clearly needed. SCY-078 is the first-in-class triterpenoid antifungal, a novel class of glucan synthase inhibitors with broad in vitro and in vivo activity against a broad spectrum of Candida and Aspergillus species. In vitro testing of clinical strains of Aspergillus fumigatus and non-fumigatus Aspergillus strains showed that SCY-078 had potent fungistatic activity (minimum effective concentration for 90% of strains tested = 0.125 µg/ml) compared with the activities of amphotericin B (MIC90 = 8 µg/ml) and voriconazole (MIC90 = 2 µg/ml). Testing of SCY-078 in combination with isavuconazole or voriconazole demonstrated synergistic activity against the majority of the azole-susceptible strains tested, and SCY-078 in combination with amphotericin B was synergistic against the azole-susceptible strains, as well as one known resistant cyp51A mutant. SCY-078 may be an important additional antifungal for first-line or salvage monotherapy or combination treatment of invasive aspergillosis.


Subject(s)
Antifungal Agents/pharmacology , Glycosides/pharmacology , Triterpenes/pharmacology , Amphotericin B/pharmacology , Aspergillus/drug effects , Aspergillus/genetics , Candida/drug effects , Candida/genetics , Glucosyltransferases/antagonists & inhibitors , Microbial Sensitivity Tests , Mutation , Nitriles/pharmacology , Pyridines/pharmacology , Triazoles/pharmacology , Voriconazole/pharmacology
10.
mBio ; 7(5)2016 09 20.
Article in English | MEDLINE | ID: mdl-27651359

ABSTRACT

UNLABELLED: Crohn's disease (CD) results from a complex interplay between host genetic factors and endogenous microbial communities. In the current study, we used Ion Torrent sequencing to characterize the gut bacterial microbiota (bacteriome) and fungal community (mycobiome) in patients with CD and their nondiseased first-degree relatives (NCDR) in 9 familial clusters living in northern France-Belgium and in healthy individuals from 4 families living in the same area (non-CD unrelated [NCDU]). Principal component, diversity, and abundance analyses were conducted, and CD-associated inter- and intrakingdom microbial correlations were determined. Significant microbial interactions were identified and validated using single- and mixed-species biofilms. CD and NCDR groups clustered together in the mycobiome but not in the bacteriome. Microbiotas of familial (CD and NCDR) samples were distinct from those of nonfamilial (NCDU) samples. The abundance of Serratia marcescens and Escherichia coli was elevated in CD patients, while that of beneficial bacteria was decreased. The abundance of the fungus Candida tropicalis was significantly higher in CD than in NCDR (P = 0.003) samples and positively correlated with levels of anti-Saccharomyces cerevisiae antibodies (ASCA). The abundance of C. tropicalis was positively correlated with S. marcescens and E. coli, suggesting that these organisms interact in the gut. The mass and thickness of triple-species (C. tropicalis plus S. marcescens plus E. coli) biofilm were significantly greater than those of single- and double-species biofilms. C. tropicalis biofilms comprised blastospores, while double- and triple-species biofilms were enriched in hyphae. S. marcescens used fimbriae to coaggregate or attach with C. tropicalis/E. coli, while E. coli was closely apposed with C. tropicalis Specific interkingdom microbial interactions may be key determinants in CD. IMPORTANCE: Here, we characterized the gut bacterial microbiota (bacteriome) and fungal community (mycobiome) in multiplex families with CD and healthy relatives and defined the microbial interactions leading to dysbiosis in CD. We identified fungal (Candida tropicalis) and bacterial (Serratia marcescens and Escherichia coli) species that are associated with CD dysbiosis. Additionally, we found that the level of anti-Saccharomyces cerevisiae antibodies (ASCA; a known CD biomarker) was associated with the abundance of C. tropicalis We also identified positive interkingdom correlations between C. tropicalis, E. coli, and S. marcescens in CD patients and validated these correlations using in vitro biofilms. These results provide insight into the roles of bacteria and fungi in CD and may lead to the development of novel treatment approaches and diagnostic assays.


Subject(s)
Crohn Disease/microbiology , Dysbiosis/microbiology , Gastrointestinal Microbiome , Microbial Interactions , Mycobiome , Adult , Biofilms/growth & development , Candida tropicalis/isolation & purification , Crohn Disease/genetics , Escherichia coli/isolation & purification , Feces/microbiology , Female , Fimbriae, Bacterial , France , Healthy Volunteers , Humans , Hyphae/isolation & purification , Male , Middle Aged , Saccharomyces cerevisiae/immunology , Serratia marcescens/isolation & purification
11.
Oral Dis ; 22 Suppl 1: 128-34, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27109281

ABSTRACT

The Oral HIV/AIDS Research Alliance (OHARA) was established in 2006 to provide the capacity to investigate the oral complications associated with HIV/AIDS within the ACTG infrastructure. Its goals were to explore the effects of potent antiretroviral therapy (ART) on the development of opportunistic infections, and variation and resistance of opportunistic pathogens in the context of immune suppression and long-term ART. The objectives of this talk, presented as part of a plenary session at the 7th World Workshop on Oral Health and Disease in AIDS, were to (i) provide an overview of OHARA's most recent research agenda, and how it evolved since OHARA's inception; (ii) describe OHARA's main accomplishments, including examples of research protocols completed and their key findings; and (iii) describe spin-off projects derived from OHARA, lessons learned, and future directions. OHARA has met its central goal and made key contributions to the field in several ways: (i) by developing/updating diagnostic criteria for oral disease endpoints commonly measured in OHARA protocols and in HIV/AIDS research in general and has creating standardized training modules, both for measuring these oral disease endpoints across clinical specialties, and for collecting oral fluid specimens; (ii) by implementing a total of nine protocols, six of which are completed. Three protocols involved domestic research sites, while three involved international research sites (in Africa, India, and South America); (iii) and by developing and validating a number of laboratory assays used in its protocols and in the field of oral HIV/AIDS research.


Subject(s)
Biomedical Research , Candidiasis, Oral/immunology , HIV Infections/complications , HIV Infections/immunology , Papillomavirus Infections/immunology , Sarcoma, Kaposi/virology , Anti-Retroviral Agents/therapeutic use , Candidiasis, Oral/virology , HIV Infections/drug therapy , Humans , Papillomavirus Infections/virology
12.
Antimicrob Agents Chemother ; 60(4): 2343-5, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26833160

ABSTRACT

The treatment of dermatophytoses, including onychomycosis, has come a long way over the past few decades with the introduction of oral antifungals (e.g., terbinafine and itraconazole). However, with these advancements in oral therapies come several undesirable effects, such as kidney and liver toxicity, along with drug-drug interactions. Consequently, there is a need for new topical agents that are effective against dermatophytosis. ME1111 is a topical antifungal under development. In this study, thein vivoefficacy of ME1111 was compared to that of ciclopirox in the topical treatment of dermatophytosis caused byTrichophyton mentagrophytesusing a guinea pig model. Animals were treated with the topical antifungals starting at 3 days postinfection, with each agent being applied once daily for seven consecutive days. After the treatment period, the clinical and mycological efficacies were evaluated. The data showed that both antifungals demonstrated significant clinical and mycological efficacies; however, ME1111 showed clinical efficacy superior to that of ciclopirox (46.9% and 25.0%, respectively, with aPvalue of <0.001). The potent efficacy of ME1111 could be attributed to its properties, such as low keratin binding.


Subject(s)
Antifungal Agents/pharmacology , Phenols/pharmacology , Pyrazoles/pharmacology , Skin/drug effects , Tinea/drug therapy , Trichophyton/drug effects , Administration, Cutaneous , Animals , Ciclopirox , Disease Models, Animal , Guinea Pigs , Male , Parasitic Sensitivity Tests , Pyridones/pharmacology , Skin/microbiology , Skin/pathology , Tinea/microbiology , Tinea/pathology , Treatment Outcome , Trichophyton/growth & development
13.
Mycoses ; 59(5): 319-26, 2016 May.
Article in English | MEDLINE | ID: mdl-26867498

ABSTRACT

As onychomycosis is unsightly, this study clinically evaluated whether the antifungal efficacy of amorolfine 5% nail lacquer (NL) was affected by a masking, natural-coloured, cosmetic nail varnish applied 24 h later; in vitro investigations were also performed. Subjects with mild-to-moderate distal subungual toenail onychomycosis were randomised to receive amorolfine 5% NL once weekly with or without cosmetic nail varnish applied 24 h later. After 12-week treatment, antifungal activity of affected toenail clippings was assessed by measurement of zones of inhibition (ZOIs) on Trichophyton mentagrophytes seeded agar plates. Mean diameters were 53.5 mm for the amorolfine 5% NL-alone group (n = 23) and 53.6 mm for amorolfine 5% NL plus cosmetic nail varnish group (n = 25). Also, mycological cultures of subungual debris at week 12 were negative for all subjects in both groups. Most subjects (88%) reported that cosmetic nail varnish masked their infected toenails. Additionally, cadaver human nails coated in vitro with or without cosmetic nail varnish 10 min or 24 h post amorolfine NL application all gave ZOIs on Trichophyton rubrum agar plates representing potent antifungal activity. In conclusion, cosmetic nail varnish applied post amorolfine had no effect on the subungual antifungal activity of amorolfine 5% NL or its penetration through toenails.


Subject(s)
Antifungal Agents/administration & dosage , Cosmetics/therapeutic use , Foot Dermatoses/drug therapy , Morpholines/administration & dosage , Onychomycosis/drug therapy , Adult , Aged , Cadaver , Cosmetics/adverse effects , Cosmetics/chemistry , Female , Humans , Male , Middle Aged
14.
J Clin Microbiol ; 54(3): 662-5, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26719434

ABSTRACT

ME1111 is a novel small molecule antifungal agent under development for the topical treatment of onychomycosis. Standardization of the susceptibility testing method for this candidate antifungal is needed. Toward this end, 8 independent laboratories determined the interlaboratory reproducibility of ME1111 susceptibility testing. In addition, we subsequently identified 2 strains as quality control (QC) isolates for the method. In the reproducibility study, 5 blinded clinical strains each of Trichophyton rubrum, Trichophyton mentagrophytes, and Epidermophyton floccosum were tested, while the QC study tested 6 blinded T. rubrum or T. mentagrophytes ATCC strains. Testing was performed in frozen microtiter panels according to the Clinical and Laboratory Standards Institute (CLSI) M38-A2 methodology. In the reproducibility study, 9 of 15 clinical strains showed interlaboratory agreement of >90% at the 80% inhibition endpoint, with a range of agreement of 76.2% to 100%. In the QC study, 4 of the 6 ATCC strains showed interlaboratory agreement of >90%. ME1111 demonstrated excellent interlaboratory agreement when tested against dermatophytes. Based on this data, the CLSI Subcommittee on Antifungal Susceptibility Tests approved the susceptibility testing of ME1111 against dermatophytes according to M38-A2 methodology, which stipulates RPMI 1640 as the test medium, an inoculum size of 1 to 3 × 10(3) CFU/ml, and an incubation time and temperature of 96 h at 35°C. The MIC endpoint should be 80% inhibition compared with the growth control. T. rubrum ATCC MYA-4438 and T. mentagrophytes ATCC 28185 were selected as QC isolates, with an acceptable range of 0.12 to 1 µg/ml for the two strains.


Subject(s)
Antifungal Agents/pharmacology , Arthrodermataceae/drug effects , Dermatomycoses/microbiology , Microbial Sensitivity Tests , Phenols/pharmacology , Pyrazoles/pharmacology , Arthrodermataceae/classification , Humans , Reproducibility of Results
15.
Antimicrob Agents Chemother ; 60(2): 1079-84, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26643334

ABSTRACT

The CLSI epidemiological cutoff values (ECVs) of antifungal agents are available for various Candida spp., Aspergillus spp., and the Mucorales. However, those categorical endpoints have not been established for Fusarium spp., mostly due to the difficulties associated with collecting sufficient CLSI MICs for clinical isolates identified according to the currently recommended molecular DNA-PCR-based identification methodologies. CLSI MIC distributions were established for 53 Fusarium dimerum species complex (SC), 10 F. fujikuroi, 82 F. proliferatum, 20 F. incarnatum-F. equiseti SC, 226 F. oxysporum SC, 608 F. solani SC, and 151 F. verticillioides isolates originating in 17 laboratories (in Argentina, Australia, Brazil, Canada, Europe, Mexico, and the United States). According to the CLSI guidelines for ECV setting, ECVs encompassing ≥97.5% of pooled statistically modeled MIC distributions were as follows: for amphotericin B, 4 µg/ml (F. verticillioides) and 8 µg/ml (F. oxysporum SC and F. solani SC); for posaconazole, 2 µg/ml (F. verticillioides), 8 µg/ml (F. oxysporum SC), and 32 µg/ml (F. solani SC); for voriconazole, 4 µg/ml (F. verticillioides), 16 µg/ml (F. oxysporum SC), and 32 µg/ml (F. solani SC); and for itraconazole, 32 µg/ml (F. oxysporum SC and F. solani SC). Insufficient data precluded ECV definition for the other species. Although these ECVs could aid in detecting non-wild-type isolates with reduced susceptibility to the agents evaluated, the relationship between molecular mechanisms of resistance (gene mutations) and MICs still needs to be investigated for Fusarium spp.


Subject(s)
Antifungal Agents/pharmacology , Fusarium/drug effects , Microbial Sensitivity Tests/methods , Americas , Drug Resistance, Multiple, Fungal , Europe , Fusarium/genetics , Fusarium/isolation & purification , Humans , Polymerase Chain Reaction/methods
16.
Antimicrob Agents Chemother ; 59(9): 5154-8, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26055386

ABSTRACT

The treatment of onychomycosis has improved considerably over the past several decades following the introduction of the oral antifungals terbinafine and itraconazole. However, these oral agents suffer from certain disadvantages, including drug interactions and potential liver toxicity. Thus, there is a need for new topical agents that are effective against onychomycosis. ME1111 is a novel selective inhibitor of succinate dehydrogenase (complex II) of dermatophyte species, whose small molecular weight enhances its ability to penetrate the nail plate. In this study, we determined the antifungal activity of ME1111 against dermatophyte strains, most of which are known to cause nail infections, as measured by the MIC (n = 400) and the minimum fungicidal concentration (MFC) (n = 300). Additionally, we examined the potential for resistance development in dermatophytes (n = 4) following repeated exposure to ME1111. Our data show that the MIC90 of ME1111 against dermatophyte strains was 0.25 µg/ml, which was equivalent to that of the comparators amorolfine and ciclopirox (0.25 and 0.5 µg/ml, respectively). ME1111 was fungicidal at clinically achievable concentrations against dermatophytes, and its MFC90s against Trichophyton rubrum and Trichophyton mentagrophytes were 8 µg/ml, comparable to those of ciclopirox. Furthermore, ME1111, as well as ciclopirox, did not induce resistance in 4 dermatophytes tested. Our studies show that ME1111 possesses potent antifungal activity and suggest that it has low potential for the development of resistance in dermatophytes.


Subject(s)
Anti-Infective Agents, Local/pharmacology , Antifungal Agents/pharmacology , Arthrodermataceae/drug effects , Arthrodermataceae/pathogenicity , Onychomycosis/microbiology , Humans , Microbial Sensitivity Tests
17.
Antimicrob Agents Chemother ; 59(4): 1992-7, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25605358

ABSTRACT

Current therapies used to treat dermatophytoses such as onychomycosis are effective but display room for improvement in efficacy, safety, and convenience of dosing. We report here that the investigational agent VT-1161 displays potent in vitro antifungal activity against dermatophytes, with MIC values in the range of ≤0.016 to 0.5 µg/ml. In pharmacokinetic studies supporting testing in a guinea pig model of dermatophytosis, VT-1161 plasma concentrations following single oral doses were dose proportional and persisted at or above the MIC values for at least 48 h, indicating potential in vivo efficacy with once-daily and possibly once-weekly dosing. Subsequently, in a guinea pig dermatophytosis model utilizing Trichophyton mentagrophytes and at oral doses of 5, 10, or 25 mg/kg of body weight once daily or 70 mg/kg once weekly, VT-1161 was statistically superior to untreated controls in fungal burden reduction (P < 0.001) and improvement in clinical scores (P < 0.001). The efficacy profile of VT-1161 was equivalent to those for doses and regimens of itraconazole and terbinafine except that VT-1161 was superior to itraconazole when each drug was dosed once weekly (P < 0.05). VT-1161 was distributed into skin and hair, with plasma and tissue concentrations in all treatment and regimen groups ranging from 0.8 to 40 µg/ml (or µg/g), at or above the MIC against the isolate used in the model (0.5 µg/ml). These data strongly support the clinical development of VT-1161 for the oral treatment of onychomycosis using either once-daily or once-weekly dosing regimens.


Subject(s)
Antifungal Agents/administration & dosage , Antifungal Agents/therapeutic use , Pyridines/administration & dosage , Pyridines/therapeutic use , Tetrazoles/administration & dosage , Tetrazoles/therapeutic use , Tinea/drug therapy , Animals , Antifungal Agents/pharmacokinetics , Dose-Response Relationship, Drug , Guinea Pigs , Itraconazole/administration & dosage , Itraconazole/therapeutic use , Male , Microbial Sensitivity Tests , Pyridines/pharmacokinetics , Skin/pathology , Tetrazoles/pharmacokinetics , Tinea/microbiology , Tinea/pathology , Tissue Distribution , Trichophyton/drug effects
18.
Antimicrob Agents Chemother ; 59(3): 1745-50, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25583714

ABSTRACT

Clinical breakpoints (CBPs) have not been established for the Mucorales and any antifungal agent. In lieu of CBPs, epidemiologic cutoff values (ECVs) are proposed for amphotericin B, posaconazole, and itraconazole and four Mucorales species. Wild-type (WT) MIC distributions (organisms in a species-drug combination with no detectable acquired resistance mechanisms) were defined with available pooled CLSI MICs from 14 laboratories (Argentina, Australia, Canada, Europe, India, Mexico, and the United States) as follows: 10 Apophysomyces variabilis, 32 Cunninghamella bertholletiae, 136 Lichtheimia corymbifera, 10 Mucor indicus, 123 M. circinelloides, 19 M. ramosissimus, 349 Rhizopus arrhizus, 146 R. microsporus, 33 Rhizomucor pusillus, and 36 Syncephalastrum racemosum isolates. CLSI broth microdilution MICs were aggregated for the analyses. ECVs comprising ≥95% and ≥97.5% of the modeled populations were as follows: amphotericin B ECVs for L. corymbifera were 1 and 2 µg/ml, those for M. circinelloides were 1 and 2 µg/ml, those for R. arrhizus were 2 and 4 µg/ml, and those for R. microsporus were 2 and 2 µg/ml, respectively; posaconazole ECVs for L. corymbifera were 1 and 2, those for M. circinelloides were 4 and 4, those for R. arrhizus were 1 and 2, and those for R. microsporus were 1 and 2, respectively; both itraconazole ECVs for R. arrhizus were 2 µg/ml. ECVs may aid in detecting emerging resistance or isolates with reduced susceptibility (non-WT MICs) to the agents evaluated.


Subject(s)
Amphotericin B/therapeutic use , Antifungal Agents/therapeutic use , Drug Resistance, Multiple, Fungal/drug effects , Itraconazole/therapeutic use , Mucorales/drug effects , Mucormycosis/drug therapy , Triazoles/therapeutic use , Humans , Microbial Sensitivity Tests
19.
Antimicrob Agents Chemother ; 59(3): 1671-9, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25561337

ABSTRACT

Esophageal candidiasis is a frequent cause of morbidity in immunocompromised patients. Isavuconazole is a novel, broad-spectrum antifungal developed for the treatment of opportunistic fungal infections. This phase 2 trial compared the efficacy and safety of three oral dosing regimens of isavuconazole with an oral fluconazole regimen in the primary treatment of uncomplicated esophageal candidiasis. The isavuconazole regimens were as follows: 200 mg on day 1 and then 50 mg once daily (arm A), 400 mg on day 1 and then 400 mg once-weekly (arm B), and 400 mg on day 1 and then 100 mg once daily (arm C). Patients in arm D received fluconazole at 200 mg on day 1 and then 100 mg once daily. The minimum treatment duration was 14 days. The primary endpoint was the rate of endoscopically confirmed clinical response at end of therapy. Safety and tolerability were also assessed. Efficacy was evaluated in 153 of 160 enrolled patients. Overall, 146 (95.4%) achieved endoscopically confirmed clinical success. Each of the isavuconazole regimens was shown to be not inferior to fluconazole, i.e., arm A versus D, -0.5% (95% confidence interval [CI] -10.0 to 9.4), arm B versus D, 3.5% (95% CI, -5.6 to 12.7), and arm C versus D, -0.2% (95% CI, -9.8 to 9.4). The frequency of adverse events was similar in arm A (n = 22; 55%), arm B (n = 18; 45%), and arm D (n = 22; 58%), but higher in arm C (n = 29; 71%). In summary, efficacy and safety of once-daily and once-weekly isavuconazole were comparable with once-daily fluconazole in the primary treatment of uncomplicated esophageal candidiasis.


Subject(s)
Antifungal Agents/administration & dosage , Antifungal Agents/adverse effects , Candidiasis/drug therapy , Fluconazole/administration & dosage , Fluconazole/adverse effects , Nitriles/administration & dosage , Nitriles/adverse effects , Pyridines/administration & dosage , Pyridines/adverse effects , Triazoles/administration & dosage , Triazoles/adverse effects , Administration, Oral , Adult , Double-Blind Method , Esophageal Diseases/drug therapy , Esophageal Diseases/microbiology , Female , Humans , Male
20.
Antimicrob Agents Chemother ; 59(4): 1844-8, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25547349

ABSTRACT

The development of a topical agent that would strengthen the nail, improve the natural barrier, and provide better drug penetration to the nail bed is needed. In this study, we examined the effects of a hydroxypropyl chitosan (HPCH)-based nail solution using a bovine hoof model. Following application of the nail solution, changes in the hardness of the hoof samples were measured using the Vickers method. Tensile and flexural strengths were tested by stretching or punching the samples, respectively. The ultrastructure was examined using scanning electron microscopy (SEM), and samples stained with periodic acid-Schiff (PAS) stain were used to determine the fungal penetration depth. The comparators included 40% urea and 70% isopropyl alcohol solutions. The HPCH nail solution increased hoof sample hardness in comparison to the untreated control sample (mean, 22.3 versus 19.4 Vickers pyramid number [HV]). Similarly, the HPCH solution increased the tensile strength (mean, 33.07 versus 28.42 MPa) and flexural strength (mean, 183.79 versus 181.20 MPa) compared to the untreated control. In contrast, the comparators had adverse effects on hardness and strength. SEM showed that the HPCH solution reduced the area of sample crumbling following abrasion compared to the untreated control (7,418 versus 17,843 pixels), and the PAS-stained images showed that the HPCH solution reduced penetration of the dermatophyte hyphae (e.g., penetration by Trichophyton mentagrophytes was <25 µm at day 9 versus 275 µm in the untreated control). Unlike chemicals normally used in cosmetic treatments, repeated application of the HPCH nail solution may help prevent the establishment of new or recurring fungal nail infection.


Subject(s)
Cattle Diseases/prevention & control , Chitosan/therapeutic use , Foot Dermatoses/prevention & control , Foot Dermatoses/veterinary , Onychomycosis/prevention & control , Onychomycosis/veterinary , Animals , Arthrodermataceae/metabolism , Cattle , Cattle Diseases/microbiology , Foot Dermatoses/pathology , Hoof and Claw/pathology , Hoof and Claw/ultrastructure , In Vitro Techniques , Lacquer , Tensile Strength , Trichophyton
SELECTION OF CITATIONS
SEARCH DETAIL
...