In vitro Susceptibility Studies with Oxiconazole (Ro 13–8996)

Abstract

Oxiconazole (Ro 13–8996) is a recently described imidazole derivative intended for topical use. 128 isolates of pathogenic fungi were tested in vitro against oxiconazole, miconazole, and ketoconazole using an agar dilution method. Results indicated that miconazole was markedly more active than either oxiconazole or ketoconazole against Candida albicans while ketoconazole was the more active compound against Candida parapsilosis. A species specific difference in the susceptibilities of isolates of Aspergillus fumigatus and Aspergillus flavus to all three imidazoles with A. flavus being more susceptible was noted. Both Mucor and Rhizopus were more susceptible to oxiconazole than to either miconazole or ketoconazole. There were no noticeable differences among the dermatophytes in tests with the three drugs with all geometric mean minimum inhibition concentrations (MIC) being less than 1.0 μgml^-1. The dematiaceous fungi also demonstrated no major differences in susceptibility to the three drugs. One isolate of Pseudallescheria boydii was relatively resistant to all three drugs (MIC ≥16 μgml^-1).

Evaluation of a novel oxiconazole nitrate formulation: The thermosensitive gel

“…Due to the lack of information about ON in the guidelines, modified azole standards and methods were used. As a solvent, DMSO is a best choice except fluconazole, which also worked excellently for ON and TGF, as previously reported (Gebhart et al, 1984). Because of the evaluation of dilution range is not clear for oxiconazole, the widest range in CLSI guidelines (0.016–128 mg/L) with 14 serial dilutions and also positive and negative control tubes were applied.…”

Conazoles

“…parapsilosis , Torulopsis glabrata and C . neoformans the compound gave MIC values ranging from 0.001 to 100 μg/mL ( Table 8 ) [ 50 , 51 ]. Furthermore strains of the moulds A .…”

“…Oxiconazole was tested in Yeast Nitrogen Base and in Casitone liquid medium against 65 C. albicans strains, resulting in a different outcome for the MIC’s ranging from < 0.1–12.5 and 0.4–50 μg/mL, respectively. These experiments made clear that the antifungal MIC of an azole compound can vary and depend on the test method (inoculum size) and can further depend on the composition and pH of the medium [ 50 , 51 ].…”

A Review of Biologically Active Oxime Ethers

“…It is active against dermatophytes and yeasts, e.g., Trichophyton rubrum , Trichophyton mentagrophytes , Epidermophyton floccosum and Malassezia furfur . It is used topically in the treatment of superficial mycosis (including athlete’s foot, skin) in the form of a cream or lotion [ 5 , 6 ].…”