sm-8668 and Disease-Models--Animal

Triazole analogues which contained alkylthio or alkylsulfonyl groups where synthesized as derivatives of antifungal SM-8668 and estimated for their in vitro and in vivo activity. Derivatives having pentylthio, heptylthio or nonylthio groups showed excellent efficacy against both candidiasis and aspergillosis. Introduction of a hydrophilic group at the end of their alkyl chain made their activity stronger. Especially, 5-hydroxypentylthio and 7-hydroxyheptylthio derivatives showed the strongest antifungal activity.

Topics: Alkylation; Animals; Antifungal Agents; Aspergillosis; Candidiasis; Disease Models, Animal; Magnetic Resonance Spectroscopy; Male; Mice; Structure-Activity Relationship; Sulfur; Triazoles

The purpose of this study was to determine if there is a correlation between production of certain lymphokines in progressive blastomycosis in untreated mice, resistance to infection in immunized mice, and cure in antifungal triazole (SCH 39304)-treated mice. Infection was measured by colony-forming units of Blastomyces dermatitidis in lungs. Serum level of IgE was used as a marker for in vivo IL-4 activity. Serum IgE levels rose in untreated mice from 6 micrograms/ml at 3 weeks to 24 micrograms/ml by the fourth week as their infection progressed. This corresponded to a peak in vitro production of IL-4 (147 pg/ml) by antigen-stimulated spleen cells at Week 4. By contrast, there was an inverse relationship between serum IgE- and antigen-stimulated production of IFN-gamma in vitro, e.g., 80 U/ml at the third week and 4 U/ml at Week 4. In mice undergoing cure with SCH 39304, serum IgE decreased from 12 micrograms/ml at the third week to 2 micrograms/ml at Week 4. This correlated with a drop in IL-4 and an increase in IFN-gamma production in in vitro assays. As cure proceeded over the next 4 weeks, IgE and IFN-gamma measurements were near background levels. In immunized mice a low-grade chronic blastomycosis emerged after 3 weeks of infection. Chronic infection was associated with inverse cycles of elevated IgE in serum and IFN-gamma production as assayed in vitro. IL-4 production cycled directly with increased IgE levels in serum. Although spleen cells from untreated mice produced IFN-gamma and IL-4 when stimulated with antigen, they did not mount significant proliferative responses. By contrast, spleen cells and lymph node cells from immunized and SCH 39304-treated mice made good proliferative responses to antigen and this correlated with resistance and clearing of the infection, respectively. These data indicate that in pulmonary blastomycosis, serum IgE levels correlate directly with IL-4 and inversely with IFN-gamma production. Clearing of the infection by the antifungal agent SCH 39304 reduces lymphokine production to background levels but sensitizes lymphocytes for proliferative responses to antigen.

Topics: Animals; Antifungal Agents; Antigens, Surface; Blastomycosis; Cells, Cultured; Disease Models, Animal; Immunization; Immunoglobulin E; Interferons; Interleukin-4; Lung; Lymph Nodes; Lymphocytes; Male; Membrane Glycoproteins; Mice; Mice, Inbred BALB C; Spleen; Thy-1 Antigens; Triazoles

Sch 39304 is a new broad spectrum triazole antifungal agent that is active, orally and topically, against superficial Trichophyton mentagrophytes and vaginal Candida albicans infections. Sch 39304 was compared to fluconazole (FLZ) in a T. mentagrophytes infection model in guinea pigs. Following topical administration, Sch 39304 (0.125%, twice daily, 10 days), was 5-8-fold more effective than FLZ, based on culture and lesion score results. Following oral administration, Sch 39304 (2.5 mg kg-1, once daily, 10 days) produced a dramatic reduction in lesion scores and was 20-fold more active than FLZ; however, due to the length of time it takes for the drugs to reach the infected area of the skin and eradicate the infections, most animals remained culture positive with both drugs. Sch 39304 was also compared with FLZ in a vaginal C. albicans infection in hamsters. Following oral administration (4 days), Sch 39304 (1.6 mg kg-1), cured all hamsters and was 4-fold more active than FLZ. In addition, Sch 39304 as a single oral dose (10 mg kg-1) also cured all hamsters. When treatment was intravaginal (8 days), Sch 39304 was again more active than FLZ (2-fold), and also micronazole (8-fold), with 100% of the hamsters cured at concentrations as low at 0.025%.

Topics: Administration, Oral; Administration, Topical; Animals; Antifungal Agents; Candidiasis, Vulvovaginal; Disease Models, Animal; Dose-Response Relationship, Drug; Female; Fluconazole; Guinea Pigs; Miconazole; Tinea; Triazoles

Current treatment modalities for bronchopulmonary aspergillosis are not very satisfying. We determined the in vitro activity of recently available azoles against Aspergillus fumigatus, Aspergillus flavus and Aspergillus niger. Subsequently, these agents were evaluated in an animal model of bronchopulmonary aspergillosis using A. fumigatus as test organism. In vitro, detectable activity was only found for itraconazole (all minimal inhibitory concentrations, MICs, less than or equal to 3.2 micrograms/ml). The MICs for SCH39304 were greater than or equal to 12.8 micrograms/ml and greater than or equal to 25.6 micrograms/ml for ketoconazole and fluconazole. In vivo, amphotericin B was the most active agent tested, and SCH39304 was the most active azole in terms of survival and reduction in lung weight, followed by itraconazole. Ketoconazole and fluconazole did not improve survival nor reduce the lung weight of infected animals. We conclude, (1) that in vitro activity of azoles against aspergilli does not always correlate with in vivo activity; (2) that in vivo, SCH39304 was the most active azole tested, followed by itraconazole; (3) that for those agents for which data about effectiveness in human pulmonary aspergillosis are available (amphotericin B, ketoconazole, itraconazole) antifungal activity in our model corresponds to activity as seen in human beings, and (4) that SCH39304 and itraconazole are rational choices for clinical trials in human pulmonary aspergillosis.

Topics: Amphotericin B; Animals; Antifungal Agents; Aspergillosis; Aspergillosis, Allergic Bronchopulmonary; Aspergillus; Aspergillus flavus; Aspergillus fumigatus; Disease Models, Animal; Itraconazole; Ketoconazole; Male; Rats; Rats, Inbred Strains; Triazoles

A comparative study, using 5 antifungal drugs for the treatment of an experimental model of murine cryptococcosis, was carried out. One hundred and eighty Balb C mice, divided in 18 groups of 10 animals each, were intraperitoneally inoculated with 10(7) cells of Cryptococcus neoformans var. neoformans. Twelve groups were treated with different schedules beginning 5 days after inoculation, for 2 or 4 weeks. The treatments were the following: amphotericin B (6 mg/kg/every other day, intraperitoneally); 5-fluorocytosine (300 mg/kg/day, by gavage); amphotericin B (6 mg/kg/every other day, intraperitoneally) in association with 5-fluorocytosine (300 mg/kg/day, by gavage); fluconazole, itraconazole and Sch 39.304 (all at the daily dose of 16 mg/kg, by gavage). The six remaining groups were used as controls and received the solvent for the drugs. The evaluation of the efficacy of the different treatments was based on: survival time; macroscopy of brain, lungs, liver and spleen at autopsies; presence of encapsulated yeasts in microscopic examination of wet preparations of these organs; and cultures of a concentrated suspension of brain and lungs. In the animals treated for 2 weeks, the combination of amphotericin B + 5-fluorocytosine was the most useful; it negativized the micro and macroscopic findings as well as 90% of the cultures, and prolonged the survival time up to 60 days. Sixty per cent of the mice which received amphotericin B exhibited the same survival time and macroscopic findings as those treated with the association of amphotericin B + 5-fluorocytosine. Among the azolic compounds, Sch 39.304 proved to be the most effective in the prolongation of survival time.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Amphotericin B; Animals; Antifungal Agents; Cryptococcosis; Cryptococcus neoformans; Disease Models, Animal; Drug Administration Schedule; Drug Therapy, Combination; Fluconazole; Flucytosine; Itraconazole; Ketoconazole; Mice; Mice, Inbred BALB C; Triazoles

We studied the in vivo antifungal activity of azoles in humans and in a murine model of disseminated trichosporonosis. Eight patients infected with Trichosporon species were treated with fluconazole, SCH 39304, or miconazole for 2-26 weeks. Four patients had fungemia, two patients had disseminated trichosporonosis, and one patient each had soft-tissue infection and cystitis. Response of trichosporonosis to azoles was seen in all eight patients, although one patient died with disseminated aspergillosis while still receiving SCH 39304. A literature review indicated that responses to ketoconazole or miconazole were noted in four patients with trichosporonosis. In the experimental infection, amphotericin B, SCH 39304, and fluconazole were effective in prolonging survival and reducing fungal counts in the kidneys of mice infected with a clinical strain of Trichosporon beigelii. Fluconazole but not amphotericin B prolonged survival of mice infected with a clinical strain of Trichosporon capitatum. We conclude that azoles represent effective therapy for infection with Trichosporon species.

Topics: Adult; Aged; Amphotericin B; Animals; Antifungal Agents; Child, Preschool; Disease Models, Animal; Female; Fluconazole; Humans; Immunocompromised Host; Male; Mice; Miconazole; Middle Aged; Mycoses; Triazoles; Trichosporon

Congenitally athymic (nu/nu) mice were inoculated sc with 10(5) conidia of Fonsecaea pedrosoi and treated orally from the 1st to the 16th week of infection with either a new triazole, SCH39304, or itraconazole at doses of 20 or 60 mg/kg/day. The volumes of the lesions were measured with calipers at 4 week intervals and compared statistically by the Wilcoxon test. At the end of the experiment, mice were killed and samples of the lesions were examined histopathologically and by electron microscopy. Treatment with itraconazole or SCH39304 significantly reduced lesion sizes as compared with controls. There were no differences between the 2 drugs at the dosages used. Histopathologically, lesions of mice treated with either drug had less inflammation with fewer fungi and more diffuse fibrosis than controls. Electron microscopy showed damage to the fungal cell walls in mice treated with itraconazole or SCH39304, characterized by gaps, fragmentation, and delamination. These studies confirm clinical observations that itraconazole is effective in chromoblastomycosis and suggest that SCH39304 should be considered for clinical evaluation.

Topics: Animals; Antifungal Agents; Chromoblastomycosis; Chronic Disease; Disease Models, Animal; Female; Itraconazole; Ketoconazole; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Microscopy, Electron; Mitosporic Fungi; Skin; Triazoles

To investigate the potential use of SCH-39304 for the prevention and treatment of disseminated candidiasis in granulocytopenic patients, we studied its in vivo antifungal activity as preventive, early, and late treatments in three models (acute, subacute, and chronic) of disseminated candidiasis in persistently granulocytopenic rabbits. SCH-39304 was an effective as amphotericin B alone and fluconazole alone for the prevention of disseminated candidiasis. SCH-39304 alone and fluconazole alone were as effective as amphotericin B plus flucytosine for early treatment of subacute disseminated candidiasis. When treatment was delayed for 5 days to establish chronic disseminated candidiasis, SCH-39304 was less effective than amphotericin B plus flucytosine. In comparison with different treatment regimens, SCH-39304 was more effective in early and preventive treatment. Thus, SCH-39304 was comparable to treatment control regimens in prevention and early treatment of subacute disseminated candidiasis. SCH-39304 also was most effective in granulocytopenic rabbits with disseminated candidiasis when used for prevention or early treatment.

Topics: Agranulocytosis; Amphotericin B; Animals; Anti-Bacterial Agents; Antifungal Agents; Candida albicans; Candidiasis; Disease Models, Animal; Female; Fluconazole; Immunosuppression Therapy; Rabbits; Triazoles