Inhibition of sterol 14 alpha-demethylation of Candida albicans with NND-502, a novel optically active imidazole antimycotic agent

In Silico Guided Nanoformulation Strategy for Circumvention of Candida albicans Biofilm for Effective Therapy of Candidal Vulvovaginitis

Candidal vulvovaginitis involving multispecies of Candida and epithelium-bound biofilm poses a drug-resistant pharmacotherapeutic challenge. The present study aims for a disease-specific predominant causative organism resolution for the development of a tailored vaginal drug delivery system. The proposed work fabricates a luliconazole-loaded nanostructured lipid carrier-based transvaginal gel for combating Candida albicans biofilm and disease amelioration. The interaction and binding affinity of luliconazole against the proteins of C. albicans and biofilm were assessed using in silico tools. A systematic QbD analysis was followed to prepare the proposed nanogel using a modified melt emulsification-ultrasonication-gelling method. The DoE optimization was logically implemented to ascertain the effect of independent process variables (excipients concentration; sonication time) on dependent formulation responses (particle size; polydispersity index; entrapment efficiency). The optimized formulation was characterized for final product suitability. The surface morphology and dimensions were spherical and ≤300 nm, respectively. The flow behavior of an optimized nanogel (semisolid) was non-Newtonian similar to marketed preparation. The texture pattern of a nanogel was firm, consistent, and cohesive. The release kinetic model followed was Higuchi (nanogel) with a % cumulative drug release of 83.97 ± 0.69% in 48 h. The % cumulative drug permeated across a goat vaginal membrane was found to be 53.148 ± 0.62% in 8 h. The skin-safety profile was examined using a vaginal irritation model (in vivo) and histological assessments. The drug and proposed formulation(s) were checked against the pathogenic strains of C. albicans (vaginal clinical isolates) and in vitro established biofilms. The visualization of biofilms was done under a fluorescence microscope revealing mature, inhibited, and eradicated biofilm structures.

Viability of pathogenic dermatophytes during a 4-week treatment with 1% topical luliconazole for tinea pedis

The viability of pathogenic fungi in the scale was investigated during topical administration of 1% luliconazole (LLCZ). Thirteen tinea pedis patients found to be positive on KOH examination were assessed by mycological examinations and quantitative real-time polymerase chain reaction (PCR) targeted internal transcribed spacer (ITS) in ribosomal RNA gene at the initial visit and after 2 and 4 weeks of treatment. Assays showed that the average copy number of ITS DNA had significantly decreased to 22.9% at 2 weeks and 4.8% at 4 weeks compared with the initial visit. LLCZ topical treatment could defeat almost pathogenic dermatophytes in the scales within 4 weeks.

Vaginitis: Review on Drug Resistance

Female genital tract infections have a high incidence among different age groups and represent an important impact on public health. Among them, vaginitis refers to inflammation of the vulva and/or vagina due to the presence of pathogens that cause trichomoniasis, bacterial vaginosis, and vulvovaginal candidiasis. Several discomforts are associated with these infections, as well as pregnancy complications and the facilitation of HIV transmission and acquisition. The increasing resistance of microorganisms to drugs used in therapy is remarkable, since women report the recurrence of these infections and associated comorbidities. Different resistant mechanisms already described for the drugs used in the therapy against Trichomonas vaginalis, Candida spp., and Gardnerella vaginalis, as well as aspects related to pathogenesis and treatment, are discussed in this review. This study aims to contribute to drug design, avoiding therapy ineffectiveness due to drug resistance. Effective alternative therapies to treat vaginitis will reduce the recurrence of infections and, consequently, the high costs generated in the health system, improving women's well-being.

Luliconazole, a new antifungal against Candida species isolated from different sources

OBJECTIVE

Luliconazole is an inhibitor for sterol 14-α-demethylase in fungal cells with a broad-spectrum antifungal activity against dermatophytes, Candida albicans, Malassezia species, dematiaceous and hyaline hyphomycetes. Furthermore, luliconazole has been clinically used for the treatment of pityriasis versicolor, dermatophytosis, onychomycosis, cutaneous and mucocutaneous candidiasis. In the present study, we aimed to evaluate in vitro antifungal activity of luliconazole against several strains of Candida species recovered from different clinical materials.

MATERIALS AND METHODS

In the present study, 104 strains of Candida species including, 34 isolates from vaginitis, 23 isolates from AIDS patients with vaginal candidiasis, 24 isolates from neutropenic patients and 24 isolates from tracheal tubes, were examined for susceptibility tests. A serial dilution of luliconazole (4-0.008μg/mL) was tested against different strains of Candida species recovered from different sources.

RESULTS

The minimum inhibitory concentration (MIC) range and MIC₉₀ of vaginal isolates (HIV^-) were 1-0.063 and 1μg/mL. Furthermore, the most of strains (50%) had a MIC of 0.5μg/mL. The MIC ranges were similar (2-0.016μg/mL) for both vaginal (HIV⁺) and neutropenic patients isolates, whereas, MIC₉₀ for them were 0.5 and 1μg/mL, respectively. All tracheal tubes strains were inhibited at the range of 2-0.008μg/mL with MIC₉₀=1μg/mL. Totally, the lowest MIC₅₀ (MIC=0.015μg/mL), MIC₉₀ (MIC=1μg/mL) and MIC_GM (MIC=0.05μg/mL) are correlated to C. glabrata, a non-albicans species.

CONCLUSION

It is concluded that, luliconazole could be an alternative anti-Candida agent, however, in vivo studies must be confirmed usefulness of drug for clinical usage.

A new more atom-efficient multi-component approach to tetrasubstituted imidazoles: one-pot condensation of nitriles, amines and benzoin

A new more atom-efficient multi-component approach for the synthesis of tetrasubstituted imidazoles via the one-pot condensation of nitriles, primary amines and benzoin has been described.

Luliconazole for the treatment of fungal infections: an evidence-based review

Luliconazole is an imidazole antifungal agent with a unique structure, as the imidazole moiety is incorporated into the ketene dithioacetate structure. Luliconazole is the R-enantiomer, and has more potent antifungal activity than lanoconazole, which is a racemic mixture. In this review, we summarize the in vitro data, animal studies, and clinical trial data relating to the use of topical luliconazole. Preclinical studies have demonstrated excellent activity against dermatophytes. Further, in vitro/in vivo studies have also shown favorable activity against Candida albicans, Malassezia spp., and Aspergillus fumigatus. Luliconazole, although belonging to the azole group, has strong fungicidal activity against Trichophyton spp., similar to that of terbinafine. The strong clinical antifungal activity of luliconazole is possibly attributable to a combination of strong in vitro antifungal activity and favorable pharmacokinetic properties in the skin. Clinical trials have demonstrated its superiority over placebo in dermatophytosis, and its antifungal activity to be at par or even better than that of terbinafine. Application of luliconazole 1% cream once daily is effective even in short-term use (one week for tinea corporis/cruris and 2 weeks for tinea pedis). A Phase I/IIa study has shown excellent local tolerability and a lack of systemic side effects with use of topical luliconazole solution for onychomycosis. Further studies to evaluate its efficacy in onychomycosis are underway. Luliconazole 1% cream was approved in Japan in 2005 for the treatment of tinea infections. It has recently been approved by US Food and Drug Administration for the treatment of interdigital tinea pedis, tinea cruris, and tinea corporis. Topical luliconazole has a favorable safety profile, with only mild application site reactions reported occasionally.

Luliconazole: a review of a new antifungal agent for the topical treatment of onychomycosis

Luliconazole is a novel, broad-spectrum, imidazole antifungal under development in the USA as a treatment for dermatophytic skin and nail infections. In vitro, luliconazole is one of the most potent antifungal agents against filamentous fungi including dermatophytes. Luliconazole has been formulated in a 10% solution with unique molecular properties, which allow it to penetrate the nail plate and rapidly achieve fungicidal levels in the nail unit. These properties make luliconazole a potent compound in the treatment of onychomycosis. This article reviews the development of luliconazole solution, 10% its molecular properties, preclinical and clinical data and its future perspectives for the treatment of fungal infections.

In vitro antifungal activity of luliconazole (NND-502), a novel imidazole antifungal agent

The in vitro activity of luliconazole (NND-502), a novel imidazole antifungal agent, against dermatophytes and several other groups of medically important fungi including the rare causative agents of dermatomycoses, was studied. The luliconazole susceptibility tests were performed with a total of 58 fungal strains of 23 species of fungi grouped into dermatophytes, dematiaceous fungi, hyaline hyphomycetes, yeastlike fungi, and zygomycetes using a broth microdilution method with RPMI 1640 medium. The minimum inhibitory concentration (MIC) values for luliconazole were compared with those of three reference drugs, lanoconazole (LCZ), bifonazole (BFZ), and terbinafine (TBF), all of which have been popular for the topical treatment of dermatophytosis, cutaneous candidiasis, and other superficial fungal infections in Japan. Luliconazole inhibited growth of all filamentous fungi except zygomycetes at low concentrations (MIC, < or =0.004-0.125 microg/ml), with dermatophytes being most susceptible (MIC, < or =0.004-0.008 microg/ml). The susceptibility of these filamentous fungi to luliconazole was almost equal to that to LCZ, and surpassed TBF and BFZ, although to a lesser extent; yeastlike fungi were also susceptible to luliconazole (MIC, 0.125-4 microg/ml). Again the anti-yeastlike fungi activity of luliconazole was at the same level as LCZ and was greater than that of BFZ and TBF. In contrast to BFZ and TBF, however, luliconazole and LCZ were virtually inactive against zygomycetes.

Six novel antimycotics

We have reviewed six new antimycotic agents which have potential applications for human cutaneous and mucosal diseases. Information on these six drugs was obtained via an English language search of PubMed through the US National Library of Medicine. The antimycotic agents reviewed include rilopirox, lanoconazole, NND-502, butenafine, eberconazole and voriconazole. Rilopirox is a synthetic pyridone derivative, related to ciclopirox, with a fungicidal action. Rilopirox is a hydrophobic, topical agent with potential application in mucosal candida infections, tinea versicolor and seborrheic dermatitis. Lanoconazole, an imidazole, is a topical agent with potential application in tinea infections and cutaneous candidiasis. The drug has been available for clinical use in Japan since 1994 and once-daily application to affected areas is recommended. In addition to its antifungal effect, animal data suggest that application of lanoconazole 0.5 or 1% cream is associated with accelerated wound healing. NND-502, a stereoselective analog of lanoconazole, is a topical agent with potential application in tinea pedis infection. NND-502 appears to be more effective in inhibiting ergosterol biosynthesis than lanoconazole or bifonazole and clinical trials comparing these agents are awaited. Butenafine is the first member of a new class of antifungals, the benzylamine derivatives, and has been approved for topical use in Japan (since 1992) and the US. Butenafine has a potent fungicidal action and the drug has been shown to be effective in multiple clinical trials in patients with tinea pedis, tinea corporis and tinea cruris. Butenafine has also been reported to exert an anti-inflammatory action after topical application and this may offer potential benefit over other topical antifungal agents. Eberconazole, an imidazole derivative, is a topical antifungal agent that has been shown to be effective in clinical trials in patients with tinea infections. Preliminary data indicate that the eberconazole is effective against some triazole-resistant yeasts such as Candida krusei and Candida glabrata. Voriconazole is an azole antifungal derivative of fluconazole. The drug is available in both oral and parenteral formulations. Oral voriconazole 200mg twice daily has been effective in treating oropharyngeal candidiasis and apergillosis in immunocompromised patients. After 12 weeks' treatment, a similar dosage of the drug elicited a positive response in 69% of nonimmunocompromised patients with invasive aspergillosis.