Using human Pompe disease-induced pluripotent stem cell-derived neural cells to identify compounds with therapeutic potential.

Pompe disease (OMIM # 232300) is a glycogen storage disease caused by autosomal recessive mutations of the gene encoding alpha-1,4-glucosidase (GAA; EC 3.2.1.20). Despite the relatively effective employment of enzyme replacement therapy, some critical medical issues still exist in patients with this disease, including the persistence of abnormalities in the central nervous system (CNS), probably because of the inability of the recombinant GAA to pass through the blood-brain barrier. To address this issue, identification of more therapeutic agents that target the CNS of patients with Pompe disease may be required. In this study, we derived neuronal cells from Pompe disease-induced pluripotent stem cells (Pom-iPSCs) and proved that they are able to recapitulate the hallmark cellular and biochemical phenotypes of Pompe disease. Using the Pom-iPSC-derived neurons as an in vitro drug-testing model, we then identified three compounds, ebselen, wortmannin and PX-866, with therapeutic potential to alleviate Pompe disease-associated pathological phenotypes in the neurons derived from Pom-iPSCs. We confirmed that all three compounds were able to enhance the GAA activity in the Pom-iPSC-derived neurons. Moreover, they were able to enhance the GAA activity in several important internal organs of GAA-deficient mice when co-injected with recombinant human GAA, and we found that intraperitoneal injection of ebselen was able to promote the GAA activity of the GAA-heterozygous mouse brain. Our results prove the usefulness of Pom-iPSC-derived neuronal populations for identifying new compounds with therapeutic potential.

Fungicide-driven alterations in azole-resistant Aspergillus fumigatus are related to vegetable crops in Colombia, South America.

Aspergillus fumigatus resistant to azole as first-line therapy has been reported in azole-naïve patients. This worldwide resistance phenomenon has been linked to fungicide-driven alterations in the cyp51A gene and its promoter region (such as TR34/L98H and TR46/Y121F/T289A). Azole-resistant A. fumigatus related to the use of triazole fungicides in flower fields was recently reported In Colombia. The purpose of this study was to investigate the presence of azole-resistant A. fumigatus in soil samples from vegetable crops such as carrots, potatoes, maize, strawberries, and pea, and from prepared farming land surrounding the city of Bogotá. Species identification was based on sequencing of the ß-tubulin and calmodulin genes. All A. fumigatus strains were screened for azole resistance on agar supplemented with itraconazole or voriconazole. Among the 60 soil samples, 34 (56.6%) were positive for A. fumigatus and 15 samples exhibited strains (n = 18) that grew on agar supplemented with itraconazole or voriconazole. Triazole-resistant strains were isolated from soil samples associated with carrot, potato, maize, and pea crops. Sequencing of the cyp51A gene and its promoter region indicated polymorphism, mainly with the presence of TR46/Y121F/T289A (n = 8), TR34/L98H, and TR53. Eight resistant isolates exhibited cyp51A wild type without alterations in the promoter region. Our study showed evidence of dissemination of azole-resistant A. fumigatus, with high genetic diversity, in vegetable crops in Colombia. These data underline the need to determine the prevalence of azole resistance in A. fumigatus in clinical and environmental settings for other regions of Colombia as well as Latin America.

A multifunctional compound ebselen reverses memory impairment, apoptosis and oxidative stress in a mouse model of sporadic Alzheimer's disease.

Alzheimer 's disease (AD) is characterized by progressive cognitive decline including memory impairment, cortical dysfunction, and neuropsychiatric disturbances. The drug discovery to treat AD consists to develop compounds able to act in multiple molecular targets involved in the pathogenesis of the disease and the repositioning of old drugs for new application. This way, the intracerebroventricular (icv) injection of streptozotocin (STZ) has been used as a metabolic model of sporadic AD. The aim of the present study was to investigate whether ebselen (1-10 mg/kg), a multifunctional selenoorganic compound, ameliorates memory impairment, hippocampal oxidative stress, apoptosis and cell proliferation in a mouse model of sporadic AD induced by icv STZ (3 mg/kg, 1 µl/min). The administration of ebselen (10 mg/kg, i.p.) reversed memory impairment and hippocampal oxidative stress, by increasing the activities of antioxidant enzymes and the level of a non-enzymatic antioxidant defense, in Swiss mice administered with icv STZ. The anti-apoptotic property of ebselen was demonstrated by its effectiveness against the increase in the ratios of Bax/Bcl-2, cleaved PARP/PARP and the cleaved caspase-3 levels in the hippocampus of icv STZ mice. Although ebselen reversed memory impairment, it was ineffective against the reduction in the number of BrdU positive cells induced by icv STZ. In conclusion, the multifunctional selenoorganic compound ebselen was effective to reverse memory impairment, hippocampal oxidative stress and apoptosis in a mouse model of sporadic AD induced by icv STZ.

Tratamiento de la enfermedad de Hailey-Hailey generalizada con fototerapia UVB de banda estrecha / Narrowband UV-B Phototherapy in the Treatment of Generalized Hailey-Hailey Disease

No disponible

Topical delivery of ebselen encapsulated in biopolymeric nanocapsules: drug repurposing enhanced antifungal activity.

AIM: Ebselen (Eb) is an example of a repurposed drug with poor aqueous solubility which requires sophisticated delivery system such as nanoencapsulation in nanocapsules for topical application. MATERIALS & METHODS: Eb-nanocapsules were examined for morphology, activity against Candida spp., cytotoxicity and skin permeation. RESULTS: Eb-nanocapsules were active against skin-infecting Candida tropicalis, Candida albicans and Candida parapsilosis yeasts (minimal inhibitory concentration values were about 4-, 2- and 1.25-times lower vs free Eb, respectively) and able to suppress induced lipid oxidation in the oil/water emulsion. Moreover, demonstrated minimal toxicity in normal human dermal fibroblast cell line, whereas ex vivo skin permeation studies showed no transdermal passage and strong interactions with stratum corneum. CONCLUSION: Eb-nanocapsules represent a promising, safe and complementary alternative to the treatment of cutaneous candidiasis.

Azole-resistant and -susceptible Aspergillus fumigatus isolates show comparable fitness and azole treatment outcome in immunocompetent mice.

No data are available on the in vivo impact of infections with in vitro azole-resistant Aspergillus fumigatus in immunocompetent hosts. Here, the aim was to investigate fungal fitness and treatment response in immunocompetent mice infected with A. fumigatus (parental strain [ps]) and isogenic mutants carrying either the mutation M220K or G54W (cyp51A). The efficacy of itraconazole (ITC) and posaconazole (PSC) was investigated in mice, intravenously challenged either with a single or a combination of ps and mutants (6 × 105 conidia/mouse). Organ fungal burden and clinical parameters were measured. In coinfection models, no fitness advantage was observed for the ps strain when compared to the mutants (M220K and G54W) independent of the presence or absence of azole-treatment. For G54W, M220K, and the ps, no statistically significant difference in ITC and PSC treatment was observed in respect to fungal kidney burden. However, clinical parameters suggest that in particular the azole-resistant strain carrying the mutation G54W caused a more severe disease than the ps strain. Mice infected with G54W showed a significant decline in body weight and lymphocyte counts, while spleen/body weight ratio and granulocyte counts were increased. In immunocompetent mice, in vitro azole-resistance did not translate into therapeutic failure by either ITC or PSC; the immune system appears to play the key role in clearing the infection.

Selenite and ebselen supplementation attenuates D-galactose-induced oxidative stress and increases expression of SELR and SEP15 in rat lens.

Selenite and ebselen supplementation has been shown to possess anti-cataract potential in some experimental animal models of cataract, however, the underlying mechanisms remain unclear. The present study was designed to evaluate the anti-cataract effects and the underlying mechanisms of selenite and ebselen supplementation on galactose induced cataract in rats, a common animal model of sugar cataract. Transmission electron microscopy images of lens fiber cells (LFC) and lens epithelial cells (LEC) were observed in D-galactose-induced experimental cataractous rats treated with or without selenite and ebselen, also redox homeostasis and expression of proteins such as selenoprotein R (SELR), 15kD selenoprotein (SEP15), superoxide dismutase 1 (SOD1), catalase (CAT), ß-crystallin protein, aldose reductase (AR) and glucose-regulated protein 78 (GRP78) were estimated in the lenses. The results showed that D-galactose injection injured rat lens and resulted in cataract formation; however, selenite and ebselen supplementation markedly alleviated ultrastructural injury of LFC and LEC. Moreover, selenite and ebselen supplementation could mitigate the oxidative damage in rat lens and increase the protein expressions of SELR, SEP15, SOD1, CAT and ß-crystallin, as well as decrease the protein expressions of AR and GRP78. Taken together, these findings for the first time reveal the anti-cataract potential of selenite and ebselen in galactosemic cataract, and provide important new insights into the anti-cataract mechanisms of selenite and ebselen in sugar cataract.

Selenium Pretreatment for Mitigation of Ischemia/Reperfusion Injury in Cardiovascular Surgery: Influence on Acute Organ Damage and Inflammatory Response.

Ischemia/reperfusion injury (IRI) contributes to morbidity and mortality after cardiovascular surgery requiring cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA). Multi-organ damage is associated with substantial decreases of blood selenium (Se) levels in patients undergoing cardiac surgery with CPB. We compared the influence of a dietary surplus of Se and pretreatment with ebselen, a mimic of the selenoenzyme glutathione peroxidase, on IRI-induced tissue damage and inflammation. Male Wistar rats were fed either a Se-adequate diet containing 0.3 ppm Se or supplemented with 1 ppm Se (as sodium selenite) for 5 weeks. Two other groups of Se-adequate rats received intraperitoneal injection of ebselen (30 mg/kg) or DMSO (solvent control) before surgery. The animals were connected to a heart-lung-machine and underwent 45 min of global ischemia during circulatory arrest at 16 °C, followed by re-warming and reperfusion. Selenite and ebselen suppressed IRI-induced leukocytosis and the increase in plasma levels of tissue damage markers (AST, ALT, LDH, troponin) during surgery but did not prevent the induction of proinflammatory cytokines (IL-6, TNF-α). Both Se compounds affected phosphorylation and expression of proteins related to stress response and inflammation: Ebselen increased phosphorylation of STAT3 transcription factor in the heart and decreased phosphorylation of ERK1/2 MAP kinases in the lungs. Selenite decreased ERK1/2 phosphorylation and HSP-70 expression in the heart. Pretreatment with selenite or ebselen protected against acute IRI-induced tissue damage during CPB and DHCA. Potential implications of their different actions with regard to molecular stress markers on the recovery after surgery represent promising targets for further investigation.

Neuroprotective effects of ebselen in traumatic brain injury model: involvement of nitric oxide and p38 mitogen-activated protein kinase signalling pathway.

Previous investigations have found that ebselen is able to treat neurodegenerative diseases caused by radical and acute total cerebral ischaemia. The aim of the present study was to investigate the neuroprotective effects of ebselen in a traumatic brain injury (TBI) model. Ninety Sprague-Dawley rats were randomly divided into five groups (n = 18 in each): (i) sham operation; (ii) an injury model group; (iii) low-dose (3 mg/kg) ebselen-treated group; (iv) a moderate-dose (10 mg/kg) ebselen-treated group; and (v) a high-dose (30 mg/kg) ebselen-treated group. The TBI model was created according using a modified weight-drop model. Neurological severity score (NSS), brain water content and histopathological deficits were assessed as parameters of injury severity. Expression of nitric oxide (NO), inducible NO synthase (iNOS) mRNA, Toll-like receptor (TLR) and phosphorylated (p-) p38 mitogen-activated protein kinase (MAPK) were examined by chemical colorimetry, quantitative polymerase chain reaction and western blotting 24 h after intragastric ebselen administration. Rats in the TBI model group exhibited markedly more severe neurological injury (higher NSS, more brain water content and more histopathological deficits) than those in the sham-operated group. Ebselen treatment significantly ameliorated the neurological injury of TBI rats in a dose-dependent manner. Moreover, ebselen significantly reduced the NO and iNOS mRNA levels and inhibited TLR4 and p-p38 MAPK expression, indicating the involvement of NO and p38 MAPK signalling pathways in the neuroprotection afforded by ebselen. In conclusion, ebselen ameliorated neurological injury, possibly by reducing NO levels and modulating the TLR4-mediated p38 MAPK signalling pathway. Therefore, ebselen may have potential to treat secondary injuries of TBI.

Effective concentration-based serum pharmacodynamics for antifungal azoles in a murine model of disseminated Candida albicans infection.

An assessment of the effective in vivo concentrations of antifungal drugs is important in determining their pharmacodynamics, and therefore, their optimal dosage regimen. Here we establish the effective in vivo concentration-based pharmacodynamics of three azole antifungal drugs (fluconazole, itraconazole, and ketoconazole) in a murine model of disseminated Candida albicans infection. A key feature of this study was the use of a measure of mycelial (m) growth rather than of yeast growth, and pooled mouse sera rather than synthetic media as a growth medium, for determining the minimum inhibitory concentrations (MICs) of azoles for C. albicans (denoted serum mMICs). The serum mMIC assay was then used to measure antifungal concentrations and effects as serum antifungal titers in the serum of treated mice. Both serum mMIC and sub-mMIC values reflected the effective in vivo serum concentrations. Supra-mMIC and mMIC effects exhibited equivalent efficacies and were concentration-independent, while the sub-mMIC effect was concentration-dependent. Following administration of the minimum drug dosage that inhibited an increase in mouse kidney fungal burden, the duration periods of these effects were similar for all drugs tested. The average duration of either the mMIC effect including the supra-mMIC effect, the sub-mMIC effect, or the post-antifungal effect (PAFE) were 6.9, 6.5 and 10.6 h, respectively. Our study suggests that the area under the curve for serum drug concentration versus time, between the serum mMIC and the sub-mMIC, and exposure time above the serum sub-mMIC after the mMIC effect, are major pharmacodynamic parameters. These findings have important implications for effective concentration-based pharmacodynamics of fungal infections treated with azoles.

Effect of pH on in vitro susceptibility of Candida glabrata and Candida albicans to 11 antifungal agents and implications for clinical use.

The treatment of vulvovaginal candidiasis (VVC) due to Candida glabrata is challenging, with limited therapeutic options. Unexplained disappointing clinical efficacy has been reported with systemic and topical azole antifungal agents in spite of in vitro susceptibility. Given that the vaginal pH of patients with VVC is unchanged at 4 to 4.5, we studied the effect of pH on the in vitro activity of 11 antifungal agents against 40 C. glabrata isolates and compared activity against 15 fluconazole-sensitive and 10 reduced-fluconazole-susceptibility C. albicans strains. In vitro susceptibility to flucytosine, fluconazole, voriconazole, posaconazole, itraconazole, ketoconazole, clotrimazole, miconazole, ciclopirox olamine, amphotericin B, and caspofungin was determined using the CLSI method for yeast susceptibility testing. Test media were buffered to pHs of 7, 6, 5, and 4. Under conditions of reduced pH, C. glabrata isolates remained susceptible to caspofungin and flucytosine; however, there was a dramatic increase in the MIC(90) for amphotericin B and every azole drug tested. Although susceptible to other azole drugs tested at pH 7, C. albicans strains with reduced fluconazole susceptibility also demonstrated reduced susceptibility to amphotericin B and all azoles at pH 4. In contrast, fluconazole-sensitive C. albicans isolates remained susceptible at low pH to azoles, in keeping with clinical observations. In selecting agents for treatment of recurrent C. glabrata vaginitis, clinicians should recognize the limitations of in vitro susceptibility testing utilizing pH 7.0.

New generation azole antifungals in clinical investigation.

Considerable progress in treating systemic mycoses has been achieved in the past years through development of new drugs in association with more advanced diagnostic procedures. Here, we review the pharmacological, microbiological and clinical development progress with the so-called 'second generation' triazoles: voriconazole, posaconazole, ravuconazole, isavuconazole and albaconazole. All these drugs exhibit a favourable pharmacokinetic and toxicity profile and possess high activity against resistant and emerging pathogens. However, only voriconazole and posaconazole have been adequately investigated in Phase III studies and have been approved by the regulatory agencies in the treatment and prophylaxis of invasive fungal infections, respectively. On the contrary, ravuconazole, isavuconazole and albaconazole have not been investigated in adequate clinical trials and, in the absence of proper data, the real possibilities of these agents as competitors for the treatment and prevention of invasive mycoses in the clinical setting are still unknown. The drug interactions and the variability in the absorption and/or metabolism of the triazoles, in particular voriconazole and posaconazole, may determine an unpredictable exposure of the pathogens to the antifungal treatments. Literature evidences strongly support the use of therapeutic drug monitoring for these triazoles which may be crucial for the proper management of severe invasive fungal infections.

Oral candidiasis of HIV-infected children undergoing sequential HIV therapies.

Candida oral flora from 52 Brazilian HIV-infected children was characterized while they received antiviral monotherapy therapy and subsequently, HAART with the use of protease inhibitor. There was a significant increase in non-C. albicans Candida isolates from 9.6-28.8% (P=0.005) after the children were placed on protease inhibitor therapy. Although Candida albicans still remained the most commonly isolated species, relative presence of C. tropicalis (n=9) followed by C. parapsilosis (n=8) markedly increased in association with protease inhibitor therapy. Furthermore, rare Candida species including C. dubliniensis, C. norvegensis, C. humicula and C. rugosa also appeared after the onset of protease inhibitor therapy. Subsequent investigation of the antifungal sensitivity of these diverse isolates, derived during protease inhibitor therapy, demonstrated some variation in antifungal sensitivity. With notable exceptions, the majority were sensitive to amphotericin B while most C. albicans and non-C. albicans Candida isolates were also susceptible to fluconazole, itraconazole and ketoconazole. Amongst exceptions was a single C. tropicalis isolates which was resistant to fluconazole (MIC>64 microl/ml) and one C. albicans-B isolate which showed cross-resistance to all azoles and amphotericin.

Threshold to N-methyl-D-aspartate-induced seizures in mice undergoing chronic nutritional magnesium deprivation is lowered in a way partly responsive to acute magnesium and antioxidant administrations.

Magnesium deficiency may be induced by a diet impoverished in magnesium. This nutritional deficit promotes chronic inflammatory and oxidative stresses, hyperexcitability and, in mice, susceptibility to audiogenic seizures. Potentiation by low-magnesium concentrations of the opening of N-methyl-D-aspartate (NMDA) receptor/calcium channel in in vitro and ex vivo studies, and responsiveness to magnesium of in vivo brain injury states are now well established. By contrast, little or no specific attention has been, however, paid to the in vivo NMDA receptor function/excitability in magnesium deficiency. The present work reports for the first time that, in mice undergoing chronic nutritional deprivation in magnesium (35 v. 930 parts per million for 27 d in OF1 mice), NMDA-induced seizure threshold is significantly decreased (38 % of normal values). The attenuation in the drop of NMDA seizure threshold (percentage of reversal) was 58 and 20 % upon acute intraperitoneal administrations of magnesium chloride hexahydrate (28 mg magnesium/kg) and the antioxidant ebselen (20 mg/kg), respectively. In nutritionally magnesium-deprived animals, audiogenic seizures are completely prevented by these compound doses. Taken as a whole, our data emphasise that chronic magnesium deprivation in mice is a nutritional in vivo model for a lowered NMDA receptor activation threshold. This nutritional model responds remarkably to acute magnesium supply and moderately to acute antioxidant administration.

Activity of amphotericin B, anidulafungin, caspofungin, micafungin, posaconazole, and voriconazole against Candida albicans with decreased susceptibility to fluconazole from APECED patients on long-term azole treatment of chronic mucocutaneous candidiasis.

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED, APS-I) is exceptionally common in Finland. Most patients have chronic oral candidiasis since childhood. Thus, most patients receive repeated courses of antifungals throughout their life. Eleven of our patients (31.4%) have become colonized with Candida albicans with decreased sensitivity to fluconazole. A total of 43 isolates of C. albicans from 23 APECED patients isolated during the years 1994 to 2004 were divided into 2 groups: fluconazole-susceptible dose-dependent (MIC, 16-32 microg/mL, 18 isolates) and fluconazole-susceptible (MIC

[Potential of anidulafungin in hematological patients]. / Potencial de anidulafungina en el paciente hematológico.

Until relatively recently, the treatment available for invasive fungal infections in hematological patients consisted of amphotericin B and azoles. Each of these groups had limitations and secondary effects. The echinocandins are a new class of antifungal agent that has shown promising results in the treatment of numerous invasive fungal infections. Anidulafungin is a new echinocandin that, in addition to showing potent in vitro activity against Aspergillus spp. and Candida spp. (including fluconazole- and amphotericin B-resistant microorganisms), also provides some advantages over other candins. In humans, these drugs are degraded through biotransformation rather than a metabolic process. No drug interactions have been found. In hematological patients, anidulafungin would play a "potential" role as empirical therapy in febrile neutropenia, as is the case of caspofungin. Given the epidemiology of Candida infection in these patients, anidulafungin could be used as initial therapy in candidemia before starting treatment with oral flucozanole, if indicated by the fungigram. This drug would also be indicated in the treatment of invasive Aspergillus spp. infections in patients with hepatic or renal insufficiency or in those taking concomitant medications. The available in vitro studies also suggest an important role for this drug in combinations of antifungal agents. Given the excellent safety profile and absence of interactions of anidulafungin, this drug will undoubtedly be of great utility in the management of difficult-to-treat mycotic infections in hematological patients.

[Potential of anidulafungin in combined therapy]. / Potencial de anidulafungina en la terapia combinada.

Combined, simultaneous or sequential antifungal therapy has often been considered an appropriate option to improve the results obtained with monotherapy. Anidulafungin belongs to the echinocandin family, which has a different mechanism of action from the remaining antifungal agents, a characteristic that heralds a good chance of synergy with other groups. However, most of the data available on the efficacy of different combinations comes from animal models of infection, "in vitro" data and case reports, while data from controlled clinical trials are scarce. The available data are insufficient to allow us to conclude that the efficacy of combined therapy is significantly superior to that of monotherapy. However, the efficacy of combined therapy may be adequate for the treatment of severe invasive mycoses associated with high mortality rates, such as forms of aspergillosis that provoke central nervous system involvement, extensive pulmonary involvement, cavitated areas, or respiratory failure and infections caused by multiresistant fungi.

[Treatment of fungal infections of upper respiratory tract and ear]. / Leczenie grzybic górnych dróg oddechowych i ucha.

Fungi, in comparison with other pathogenic factors, have high pathogenicity. The number of fungal species which are able to infect people is over 500. The upper respiratory tract and ear have permanent contact with external environment which makes their ontocenoses open to continuous exchange of microorganisms of which they consist. In etiology of inflammatory processes 21 species which belonging to 3 genera (Zygomycota, Ascomycota, Basidiomycota) of fungi play important role. Administration of antifungal drugs can be: prophylactic, empiric preemptive and therapeutic. Physicians may prescribe antibiotics (mainly pollens: amphotericin B, natamycin and nystatin) and chemiotherapeutics (mainly azoles and fluorpirymidins, pigments, chlorhexidine and chlorquinaldol). In ENT practice topical and systemic drugs can be administrated. Topical lozenges include amphotericin B, clotrimazole, chlorhexidine or chlorquinaldol and oral gels: nystatin and miconazole. Some of drugs are in the form of suspension/solution, which can be used for inhalation, into the sinus, for swabbing or for lavage: amphotericin B, natamycin, nystatin, clotrimazol, flucytosine, miconazole, fluconazole, vorykonazole, caspofungin. It should be underlined that only a few of dugs can be absorbed from the digestive tract: flucytosine, fluconazole, itraconazole, ketoconazole, miconazole, vorykonazole.

Chemotherapeutic evaluation of alginate nanoparticle-encapsulated azole antifungal and antitubercular drugs against murine tuberculosis.

The present study was designed to evaluate the chemotherapeutic potential of alginate nanoparticle-encapsulated econazole and antitubercular drugs (ATDs) against murine tuberculosis. Alginate nanoparticles encapsulating econazole and ATDs were prepared by the cation-induced controlled gelification of alginate and were characterized. Drugs were analyzed by high-performance liquid chromatography. All the ATDs were detected above minimum inhibitory concentrations for as long as 15 days and econazole until the day 8 in organs (lungs, liver, and spleen) after administration of encapsulated drugs, whereas free drugs remained detectable for only 12 to 24 hours. Eight doses of alginate nanoparticle-encapsulated econazole or 112 doses of free econazole reduced bacterial burden by more than 90% in the lungs and spleen of mice infected with Mycobacterium tuberculosis. Econazole (free or encapsulated) could replace rifampicin and isoniazid during chemotherapy of murine tuberculosis. Alginate nanoparticles reduced the dosing frequency of azoles and ATDs by 15-fold. Alginate nanoparticles are the ideal carriers of azole and antitubercular drugs, which can reduce dosing frequency of azoles as well as ATDs for the better management of tuberculosis.

Design of clinical trials of empiric antifungal therapy in patients with persistent febrile neutropenia: considerations and critiques.

Febrile neutropenic patients who receive antibiotics are at risk for fungal infections. This risk increases greatly with the length and severity of neutropenia. Because diagnostic tests for fungal infections lack sensitivity and specificity and because established fungal infections are associated with poor outcomes, empiric antifungal therapy is frequently given to patients with fever that persists despite antibacterial therapy. Early trials of empiric amphotericin B showed reductions in the number of invasive fungal infections and in related morbidity and mortality. However, as a result of infusion-related and renal adverse effects of amphotericin B, newer agents, such as lipid formulations of amphotericin B, extended-spectrum azoles, and echinocandins, have been developed. Although these alternatives have been associated with decreased toxicity, improved efficacy has not been clearly demonstrated. Although empiric antifungal therapy can prevent undetected breakthrough infections and morbidity associated with many fungal infections, its shortcomings include overtreatment, toxicity, and increased costs of unnecessary treatment. Recent studies have highlighted several questions in trial design and data interpretation. For example, what is the appropriate study design? Who should be enrolled in studies of empiric antifungal therapy? How should successful therapy be defined? These issues are reviewed to determine whether new antifungal agents should be evaluated for empiric use in patients with fever and neutropenia.