Diabetes Exacerbates Infection via Hyperinflammation by Signaling through TLR4 and RAGE.

For more than a century, diabetic patients have been considered immunosuppressed due to defects in phagocytosis and microbial killing. We confirmed that diabetic mice were hypersusceptible to bacteremia caused by Gram-negative bacteria (GNB), dying at inocula nonlethal to nondiabetic mice. Contrary to the pervasive paradigm that diabetes impedes phagocytic function, the bacterial burden was no greater in diabetic mice despite excess mortality. However, diabetic mice did exhibit dramatically increased levels of proinflammatory cytokines in response to GNB infections, and immunosuppressing these cytokines with dexamethasone restored their resistance to infection, both of which are consistent with excess inflammation. Furthermore, disruption of the receptor for advanced glycation end products (RAGE), which is stimulated by heightened levels of AGEs in diabetic hosts, protected diabetic but not nondiabetic mice from GNB infection. Thus, rather than immunosuppression, diabetes drives lethal hyperinflammation in response to GNB by signaling through RAGE. As such, interventions to improve the outcomes from GNB infections should seek to suppress the immune response in diabetic hosts.IMPORTANCE Physicians and scientists have subscribed to the dogma that diabetes predisposes the host to worse outcomes from infections because it suppresses the immune system. This understanding was based largely on ex vivo studies of blood from patients and animals with diabetes. However, we have found that the opposite is true and worse outcomes from infection are caused by overstimulation of the immune system in response to bacteria. This overreaction occurs by simultaneous ligation of two host receptors: TLR4 and RAGE. Both signal via a common downstream messenger, MyD88, triggering hyperinflammation. In summary, contrary to hundred-year-old postulations about immune suppression in diabetic hosts, we find that diabetes instead predisposes to more severe infections because of additional inflammatory output through dual activation of MyD88 by not only TLR4 but also RAGE. It is the activation of RAGE during GNB infections in those with diabetes that accounts for their heightened susceptibility to infection compared to nondiabetic hosts.

The investigational agent E1210 is effective in treatment of experimental invasive candidiasis caused by resistant Candida albicans.

The in vitro and in vivo activity of the inositol acyltransferase inhibitor E1210 was evaluated against echinocandin-resistant Candida albicans. E1210 demonstrated potent in vitro activity, and in mice with invasive candidiasis caused by echinocandin-resistant C. albicans, oral doses of 10 and 40 mg E1210/kg of body weight twice daily significantly improved survival and reduced fungal burden compared to those of controls and mice treated with caspofungin (10 mg/kg/day). These results demonstrate the potential use of E1210 against resistant C. albicans infections.

Madurella mycetomatis is highly susceptible to ravuconazole.

The current treatment of eumycetoma utilizing ketoconazole is unsatisfactory because of high recurrence rates, which often leads to complications and unnecessary amputations, and its comparatively high cost in endemic areas. Hence, an effective and affordable drug is required to improve therapeutic outcome. E1224 is a potent orally available, broad-spectrum triazole currently being developed for the treatment of Chagas disease. E1224 is a prodrug that is rapidly converted to ravuconazole. Plasma levels of E1224 are low and transient, and its therapeutically active moiety, ravuconazole is therapeutically active. In the present study, the in vitro activity of ravuconazole against Madurella mycetomatis, the most common etiologic agent of eumycetoma, was evaluated and compared to that of ketoconazole and itraconazole. Ravuconazole showed excellent activity with MICs ranging between ≤ 0.002 and 0.031 µg/ml, which were significantly lower than the MICs reported for ketoconazole and itraconazole. On the basis of our findings, E1224 with its resultant active moiety, ravuconazole, could be an effective and affordable therapeutic option for the treatment of eumycetoma.

Activities of E1210 and comparator agents tested by CLSI and EUCAST broth microdilution methods against Fusarium and Scedosporium species identified using molecular methods.

Fusarium (n = 67) and Scedosporium (n = 63) clinical isolates were tested by two reference broth microdilution (BMD) methods against a novel broad-spectrum (active against both yeasts and molds) antifungal, E1210, and comparator agents. E1210 inhibits the inositol acylation step in glycophosphatidylinositol (GPI) biosynthesis, resulting in defects in fungal cell wall biosynthesis. Five species complex organisms/species of Fusarium (4 isolates unspeciated) and 28 Scedosporium apiospermum, 7 Scedosporium aurantiacum, and 28 Scedosporium prolificans species were identified by molecular techniques. Comparator antifungal agents included anidulafungin, caspofungin, itraconazole, posaconazole, voriconazole, and amphotericin B. E1210 was highly active against all of the tested isolates, with minimum effective concentration (MEC)/MIC(90) values (µg/ml) for E1210, anidulafungin, caspofungin, itraconazole, posaconazole, voriconazole, and amphotericin B, respectively, for Fusarium of 0.12, >16, >16, >8, >8, 8, and 4 µg/ml. E1210 was very potent against the Scedosporium spp. tested. The E1210 MEC(90) was 0.12 µg/ml for S. apiospermum, but 1 to >8 µg/ml for other tested agents. Against S. aurantiacum, the MEC(50) for E1210 was 0.06 µg/ml versus 0.5 to >8 µg/ml for the comparators. Against S. prolificans, the MEC(90) for E1210 was only 0.12 µg/ml, compared to >4 µg/ml for amphotericin B and >8 µg/ml for itraconazole, posaconazole, and voriconazole. Both CLSI and EUCAST methods were highly concordant for E1210 and all comparator agents. The essential agreement (EA; ±2 doubling dilutions) was >93% for all comparisons, with the exception of posaconazole and F. oxysporum species complex (SC) (60%), posaconazole and S. aurantiacum (85.7%), and voriconazole and S. aurantiacum (85.7%). In conclusion, E1210 exhibited very potent and broad-spectrum antifungal activity against azole- and amphotericin B-resistant strains of Fusarium spp. and Scedosporium spp. Furthermore, in vitro susceptibility testing of E1210 against isolates of Fusarium and Scedosporium may be accomplished using either of the CLSI or EUCAST BMD methods, each producing very similar results.

In vitro activity of a novel broad-spectrum antifungal, E1210, tested against Aspergillus spp. determined by CLSI and EUCAST broth microdilution methods.

E1210 is a first-in-class broad-spectrum antifungal that suppresses hyphal growth by inhibiting fungal glycophosphatidylinositol (GPI) biosynthesis. In the present study, we extend these findings by examining the activity of E1210 and comparator antifungal agents against Aspergillus spp. by using the methods of the Clinical and Laboratory Standards Institute (CLSI) and the European Committee for Antimicrobial Susceptibility Testing (EUCAST) to test wild-type (WT) as well as amphotericin B (AMB)-resistant (-R) and azole-R strains (as determined by CLSI methods). Seventy-eight clinical isolates of Aspergillus were tested including 20 isolates of Aspergillus flavus species complex (SC), 22 of A. fumigatus SC, 13 of A. niger SC, and 23 of A. terreus SC. The collection included 15 AMB-R (MIC, ≥ 2 µg/ml) isolates of A. terreus SC and 10 itraconazole-R (MIC, ≥ 4 µg/ml) isolates of A. fumigatus SC (7 isolates), A. niger SC (2 isolates), and A. terreus SC (1 isolate). Comparator antifungal agents included anidulafungin, caspofungin, amphotericin B, itraconazole, posaconzole, and voriconazole. Both CLSI and EUCAST methods were highly concordant for E1210 and all comparators. The essential agreement (EA; ± 2 log(2) dilution steps) was 100% for all comparisons with the exception of posaconazole versus A. terreus SC (EA = 91.3%). The minimum effective concentration (MEC)/MIC(90) values (µg/ml) for E1210, anidulafungin, caspofungin, itraconazole, posaconazole, and voriconazole, respectively, were as follows for each species: for A. flavus SC, 0.03, ≤ 0.008, 0.12, 1, 1, and 1; for A. fumigatus SC, 0.06, 0.015, 0.12, >8, 1, and 4; for A. niger SC, 0.015, 0.03, 0.12, 4, 1, and 2; and for A. terreus SC, 0.06, 0.015, 0.12, 1, 0.5, and 1. E1210 was very active against AMB-R strains of A. terreus SC (MEC range, 0.015 to 0.06 µg/ml) and itraconazole-R strains of A. fumigatus SC (MEC range, 0.03 to 0.12 µg/ml), A. niger SC (MEC, 0.008 µg/ml), and A. terreus SC (MEC, 0.015 µg/ml). In conclusion, E1210 was a very potent and broad-spectrum antifungal agent regardless of in vitro method applied, with excellent activity against AMB-R and itraconazole-R strains of Aspergillus spp.

Pharmacokinetics, disposition, and metabolism of bicifadine in humans.

Bicifadine [DOV 220,075; (+/-)-1-(4-methylphenyl)-3-azabicyclo-[3.1.0]hexane HCl)] is a non-narcotic analgesic that has proven to be effective for the treatment of acute pain in clinical studies. The pharmacokinetics, disposition, and metabolism of bicifadine were determined in eight healthy adult male subjects following a single oral dose of 200 mg of [(14)C]bicifadine in solution. The maximum concentration of total drug equivalents and bicifadine in plasma was at approximately 1 h; the elimination half-life was 2.6 and 1.6 h for radioactivity and bicifadine, respectively. Unchanged bicifadine represented 15% of the area under the concentration-time curve for total drug equivalents; the rest was due mainly to the lactam (M12), the acid (M3), and the lactam acid (M9). Total recovery of the dose was 92%, with most of the radioactivity recovered in the urine in the first 24 h; fecal excretion accounted for only 3.5% of the dose. Approximately 64% of the dose was metabolized to M9 and its acyl glucuronide; another 23% was recovered as M3 and its acyl glucuronide. Neither bicifadine nor M12 were detected in urine or feces. There were no reported serious or severe adverse events during the study.

Efficacy of ofloxacin otic solution once daily for 7 days in the treatment of otitis externa: a multicenter, open-label, phase III trial.

BACKGROUND: Otitis externa (OE) is an infection of the external auditory canal that is typically treated with topically applied broad-spectrum antibiotics. Twice-daily topical treatment with ofloxacin otic 0.3% solution for 10 days has been reported to be as effective and well tolerated as the standard of care, neomycin sulfate/polymyxin B sulfate/hydrocortisone solution administered 4 times daily for 10 days. OBJECTIVE: This study evaluated the efficacy and safety profile of 7 days of a once-daily regimen of ofloxacin otic 0.3% solution in the treatment of OE. METHODS: This multicenter, open-label, Phase III study was conducted from June 12, 2002, to October 14, 2002. Eligible patients were aged > or = 6 months and had OE of <2 weeks' duration with moderate to severe edema and tenderness involving 1 or both ears and sufficient exudate for microbiologic culture. Ofloxacin otic solution was instilled once daily for 7 days (5 drops for children aged 6 months to <13 years, 10 drops for adolescents/adults aged > or = 13 years). Assessments were conducted at the end-of-treatment visit and 7 to 10 days later (the test-of-cure visit). Medication was supplied free of charge to study participants who incurred no costs for physician visits. RESULTS: Of 489 patients enrolled at 58 sites in 3 countries, 439 were clinically evaluable (173 children, 266 adolescents/adults; 52 % males, 48% females; 47% Hispanic, 45% white; 5% black, and 3% other). The cure rate among clinically evaluable patients was 91% (95% of children, 88% of adolescents/adults); 68% of patients were cured within 7 days. Forty-three potentially pathogenic strains were isolated from 253 microbiologically evaluable patients. Pseudomonas aeruginosa was isolated from 158 (62%) microbiologically evaluable patients and Staphylococcus aureus from 32 (13%). Eradication rates were 96% overall. No serious adverse events were observed. Minor adverse events were experienced by 15 (3%) of 489 patients included in the safety population. The most common adverse events were pruritus (5 patients), increased earache (4 patients), and application-site reactions (3 patients). Overall mean (SD) adherence to therapy was 98% (11.9). CONCLUSIONS: Ofloxacin otic 0.3% solution administered once daily for 7 days was well tolerated and effective in achieving clinical and microbiologic cure of OE. The compliance rates in this study suggests that this regimen may be better accepted by patients than longer, more repetitive regimens.

Declining susceptibility to neomycin and polymyxin B of pathogens recovered in otitis externa clinical trials.

BACKGROUND: Otitis externa is usually treated empirically with topical neomycin/polymyxin B/hydrocortisone. The predominant pathogens associated with this infection are Pseudomonas aeruginosa and Staphylococcus aureus. METHODS: Two multicenter clinical trials (one in adults and adolescents, and one in children), conducted between 1995 and 1996, compared neomycin/polymyxin B/hydrocortisone with ofloxacin for the treatment of otitis externa; two similar trials were conducted between 1999 and 2000. Assessments included the minimum inhibitory concentrations (MICs) of each antimicrobial drug for the major pathogens, bacterial eradication, and clinical efficacy. RESULTS: The MICs of all bacterial isolates (including P. aeruginosa) for neomycin and polymyxin B increased markedly in the 1999 to 2000 studies compared with the 1995 to 1996 studies. In the later studies, mean MICs for all major pathogens tested had increased above the breakpoint for polymyxin B (> or = 4 microg/ml). In contrast, MICs of all isolates for ofloxacin remained similar between the two study periods and were within the susceptible range for this drug. CONCLUSIONS: Although the bacterial eradication rates for both treatments in each study were equivalent, the clinical cure rate for neomycin/polymyxin B/hydrocortisone was lower (87%) than for ofloxacin (93%). Therefore, the organisms most often causing otitis externa appear to be developing resistance to neomycin and polymyxin B but not to ofloxacin.