Intravenous itraconazole followed by oral itraconazole in the treatment of invasive pulmonary aspergillosis in patients with hematologic malignancies, chronic granulomatous disease, or AIDS

Invasive aspergillosis: epidemiology, diagnosis and management in immunocompromised patients

Morbidity and mortality caused by invasive Aspergillus infections are increasing. This is because of the higher number of patients with malignancies treated with intensive immunosuppressive therapy regimens as well as their improved survival from formerly fatal bacterial infections, and the rising number of patients undergoing allogeneic haematopoietic stem cell or organ transplantation. Early initiation of effective systemic antifungal treatment is essential for a successful clinical outcome in these patients; however, clinical clues for diagnosis are sparse and early microbiological proof of invasive aspergillosis (IA) is rare. Clinical diagnosis is based on pulmonary CT scan findings and non-culture based diagnostic techniques such as galactomannan or DNA detection in blood or bronchoalveolar lavage samples. Most promising outcomes can be expected in patients at high risk for aspergillosis in whom antifungal treatment has been started pre-emptively, backed up by laboratory and imaging findings. The gold standard of systemic antifungal treatment is voriconazole, which has been proven to be significantly superior to conventional amphotericin B and has led to a profound improvement of survival rates in patients with cerebral aspergillosis. Liposomal amphotericin B at standard dosages appears to be a suitable alternative for primary treatment, while caspofungin, amphotericin B lipid complex or posaconazole have shown partial or complete response in patients who had been refractory to or intolerant of primary antifungal therapy. Combination therapy with two antifungal compounds may be a promising future strategy for first-line treatment. Lung resection helps to prevent fatal haemorrhage in single patients with pulmonary lesions located in close proximity to larger blood vessels, but is primarily considered for reducing the risk of relapse during subsequent periods of severe immunosuppression. Strict reverse isolation appears to reduce the incidence of aspergillosis in allogeneic stem cell transplant recipients and patients with acute myeloid leukaemia undergoing aggressive anticancer therapy. Well designed, prospective randomised studies on infection control measures effective to prevent aspergillosis are lacking. Prophylactic systemic antifungal treatment with posaconazole significantly improves survival and reduces IA in acute myeloid leukaemia patients and reduces aspergillosis incidence rates in patients with intermediate-to-severe graft-versus-host reaction emerging after allogeneic haematopoietic stem cell transplantation. Voriconazole prophylaxis may be suitable for prevention of IA as well; however, the results of large clinical trials are still awaited.

Induction of the NAD(P)H:quinone oxidoreductase 1 by ketoconazole and itraconazole: a mechanism of cancer chemoprotection

Studies in many carcinogen-induced animal models and cell lines demonstrated that azole antifungal drugs are therapeutically effective against different types of cancer. Yet, the molecular mechanisms involved are still poorly understood. Therefore, we examined the ability of three structurally different antifungal drugs, ketoconazole (KTZ), itraconazole (ITZ), and fluconazole (FLZ) to induce the expression of NAD(P)H:quinone oxidoreductase 1 (Nqo1), an enzyme known to play an important role in xenobiotic and carcinogen detoxifications. We showed that KTZ and ITZ, but not FLZ, induced Nqo1 mRNA and enzymatic activity levels in a concentration- and time-dependent manner in wild-type but not aryl hydrocarbon receptor (AhR)-deficient Hepa 1c1c7 cells. Furthermore, KTZ and ITZ increased Nqo1 de novo RNA synthesis without significantly affecting the levels of existing RNA, suggesting a transcriptional mechanism is involved. This study provides the first evidence for the ability of KTZ and ITZ to induce the Nqo1 gene expression through an AhR-dependent mechanism.

Improved outcomes associated with advances in therapy for invasive fungal infections in immunocompromised hosts

Invasive fungal infections cause substantial morbidity and mortality in immunocompromised hosts. The response rate to therapy, in particular for invasive aspergillosis and invasive mould infections, has been poor. Recently a number of techniques to facilitate early diagnosis of these infections, in parallel with the development of a number of antifungals with increased potency and lower toxicity, have raised optimism that outcomes for invasive fungal infection can be improved upon. The availability of lipid formulations of amphotericin B, azoles with extended spectrum against filamentous fungi and the development of a new class of antifungal agents, the echinocandins, presents the clinician with a range of therapeutic choices. Recent clinical trials have provided important insights into how these agents should be used. In particular, voriconazole has demonstrated superior efficacy to amphotericin B in the management of invasive aspergillosis, posaconazole has been shown to have significant efficacy in the prophylaxis of invasive fungal infection in high-risk individuals and a role in salvage therapy of invasive aspergillosis, caspofungin has demonstrated efficacy in salvage therapy of invasive aspergillosis, and each of the echinocandins show activity without significant toxicity in invasive candidiasis. Nevertheless, many therapeutic areas of uncertainty remain, including the role of combination therapy, and will provide the focus for future studies.

Nosocomial fungal infections: epidemiology, diagnosis, and treatment

Invasive fungal infections are increasingly common in the nosocomial setting. Furthermore, because risk factors for these infections continue to increase in frequency, it is likely that nosocomial fungal infections will continue to increase in frequency in the coming decades. The predominant nosocomial fungal pathogens include Candida spp., Aspergillus spp., Mucorales, Fusarium spp., and other molds, including Scedosporium spp. These infections are difficult to diagnose and cause high morbidity and mortality despite antifungal therapy. Early initiation of effective antifungal therapy and reversal of underlying host defects remain the cornerstones of treatment for nosocomial fungal infections. In recent years, new antifungal agents have become available, resulting in a change in standard of care for many of these infections. Nevertheless, the mortality of nosocomial fungal infections remains high, and new therapeutic and preventative strategies are needed.

Fungal pneumonia due to molds in patients with hematological malignancies

Invasive fungal infections are an important cause of morbidity and mortality in patients with hematological malignancies. In particular, patients with neutropenia and those who have undergone allogeneic hematopoietic stem cell transplantation are at highest risk, with fungal pneumonia being the main clinical manifestation in these patients. The most common pathogens associated with fungal pneumonia are Aspergillus spp. and Zygomycetes. However, other pathogens have also been observed in fungal pneumonia, including Cryptococcus spp., Pneumocystis jirovecii, and Candida spp. This comprehensive review will focus on the important practical aspects relevant to the epidemiology, clinical diagnosis, and therapeutic management of pneumonia due to filamentous fungi in patients affected by hematological malignancies.

Pharmacokinetics of itraconazole and hydroxyitraconazole in healthy subjects after single and multiple doses of a novel formulation

Originally, itraconazole for parenteral administration was licensed in a 40% hydroxypropyl-beta-cyclodextrin (HPBCD) solution for intravenous administration. A novel formulation, the NanoCrystal formulation (NCF), was prepared. NCF consists of drug particles of approximately 200 to 300 nm. The pharmacokinetics of itraconazole and its hydroxy metabolite in healthy subjects were evaluated after single and multiple doses of itraconazole as NCF. In the single-ascending-dose (SAD) study, itraconazole doses were planned to range from 50 to 500 mg, while in the multiple-ascending-dose (MAD) study, itraconazole doses of 100, 200, and 300 mg as NCF were studied, as was one dose level (200 mg) as an HBPCD solution. Samples were collected in heparinized tubes at various time points and were analyzed by high-performance liquid chromatography to allow full pharmacokinetic analysis both after the first dose and on day 7. The results of both the SAD and the MAD studies indicated that there was a dose dependency in the half-life of itraconazole from the novel formulation, increasing from 44 h (100 mg) to more than 150 h (300 mg) once steady state was achieved. Similar dose-dependent effects were observed for the hydroxy metabolite. The areas under the concentration-time curves for itraconazole and hydroxyitraconazole were also dose dependent. The pharmacokinetic profiles after 200-mg doses of itraconazole as NCF and HPBCD formulations were comparable with respect to the terminal half-life, both after a single dose and at steady state. NCF may provide an alternative to the HPBCD solution for the further optimization of antifungal treatment with itraconazole.

[Efficacies and clinical roles of new antifungal agents]

Micafungin, a new class of the antifungal agent "echinocandin" released in 2002, and voriconazole, a new triazole antifungal agent released in 2005 in Japan have in vitro activities against Aspergillus spp. Results of large-scale clinical trials in Europe and the United States showed voriconazole to have superior efficacy against invasive pulmonary aspergillosis in comparison with conventional amphotericin B, and caspofungin, a member of the echinocandins, was effective as an empirical antifungal therapy in patients with persistent fever and neutropenia. In this way, choices of therapeutic medicine for aspergillosis are increasing more and more, and it is expected that the method of treatment will change greatly in future. On the other hand, we need to establish a new standard therapy for aspergillosis to avoid the clinical disruption caused by the variety of pharmaceutical choice caused. In this report, we describe the role of new antifungal agents for non-fumigatus Aspergillus infections, and the breakthrough in counteracting fungal infection using these new drugs.

Itraconazole prophylaxis in pediatric cancer patients receiving conventional chemotherapy or autologous stem cell transplants

GOAL OF WORK

During the renovation works at our institution, the incidence density for invasive aspergillosis (IA) increased from <0.5 to 0.99/1,000 inpatient days in 2001. As a direct response to this increased environmental risk, itraconazole (ITC) was administered for primary prophylaxis in pediatric cancer patients for whom a particular high risk of IA was anticipated due to prolonged severe neutropenia (>10 days), autologous stem cell transplantation, acute myeloblastic leukemia or relapsed acute lymphoblastic leukemia, or high-dose steroids >3 weeks.

MATERIALS AND METHODS

In this open-label, prospective observational study, ITC was given in ITC solution or capsule. Trough concentrations were measured in plasma with high-performance liquid chromatography after at least 7 days of treatment. Doses were adjusted to target plasma trough ITC concentrations > or =0.5 mg/l.

RESULTS

From 2001 to 2005, 39 pediatric cancer patients received 44 prophylactic ITC cycles; 102 trough plasma concentrations were measured after oral administration. Plasma target concentrations >0.5 mg/l were achieved with both formulations. A median dose of 8 mg kg(-1) day(-1) (3.5-16.0 mg kg(-1) day(-1)) was necessary in pediatric oncology patients. The bioavailability of the liquid formulation was significantly lower when the solution was given by a feeding tube. Adverse effects (gastrointestinal, elevated transaminases, and one hemolysis) which led to the cessation of the ITC prophylaxis were reported in 11% of all courses. No breakthrough infection was seen in this pediatric population.

CONCLUSION

Oral ITC offers a feasible and inexpensive option for antifungal prophylaxis in selected pediatric cancer patients. Drug monitoring and meticulous consideration of possible interactions and adverse effects are mandatory.

Comparative efficacies, toxicities, and tissue concentrations of amphotericin B lipid formulations in a murine pulmonary aspergillosis model

Invasive aspergillosis, an important cause of morbidity and mortality in immunosuppressed (IS) patients, is often treated with amphotericin B lipid formulations. In the present study, liposomal amphotericin B (L-AMB) and amphotericin B lipid complex (ABLC) were compared in treatment of murine pulmonary aspergillosis. Uninfected, IS mice were treated for 4 days with 1, 4, 8, or 12 mg L-AMB or ABLC/kg of body weight, and their lungs were analyzed by high-performance liquid chromatography for drug concentrations. IS mice intranasally challenged with Aspergillus fumigatus were treated with 12, 15, or 20 mg/kg L-AMB or ABLC and monitored for survival, fungal burden (CFU), and tissue drug concentration. Blood urea nitrogen (BUN) levels and kidney histopathology were determined for uninfected and infected mice given 15 or 20 mg/kg L-AMB or ABLC. The results showed that both drugs had therapeutic levels of drug (>3.0 microg/g) in the lungs of uninfected or infected mice, and 24 h after the last dose, ABLC levels were significantly higher than L-AMB levels (P < 0.02). L-AMB and ABLC at 12 mg/kg both produced 57% survival, but only L-AMB at 15 or 20 mg/kg further increased survival to 80 to 90%, with BUN levels and kidney morphology similar to those of controls. Survival at 15 or 20 mg/kg ABLC was not significantly different than that of controls, and BUN levels were significantly elevated, with tubular alterations in uninfected animals and acute necrosis in kidney tubules of infected animals. In conclusion, although both drugs were effective in prolonging survival at 12 mg/kg, the reduced nephrotoxicity of L-AMB increased its therapeutic index, allowing for its safe and effective use at 15 or 20 mg/kg.

Adverse effects of antifungal therapies in invasive fungal infections: review and meta-analysis

Amphotericin B is the main therapeutic agent for the treatment of invasive fungal infections; however, it is associated with significant toxicities that limit its use. Other systemic antifungal agents have been developed to improve tolerability while maintaining the efficacy profile of conventional amphotericin B. Fifty-four studies involving 9,228 patients were assessed for the frequency of adverse effects of the main systemic antifungal agents. While the results suggest that liposomal amphotericin B is the least nephrotoxic of the lipid formulations (14.6%), that conventional amphotericin B is the most nephrotoxic (33.2%), and that itraconazole is the most hepatotoxic (31.5%), the lack of standard definitions of antifungal-related adverse effects limits the validity of these results. Furthermore, heterogeneous patient pools and differing protocols make it difficult to draw direct comparisons between studies. With the advent of newer classes of systemic antifungal agents, future trials should conform to definitions that are universally applicable and clinically relevant to allow for such comparisons and to enable evidence-based decision-making.

Update on antifungal drug resistance mechanisms of Aspergillus fumigatus

Although the arsenal of agents with anti-Aspergillus activity has expanded over the last decade, mortality due to invasive aspergillosis (IA) remains unacceptably high. Aspergillus fumigatus still accounts for the majority of cases of IA; however less susceptible to antifungals non-fumigatus aspergilli began to emerge. Antifungal drug resistance of Aspergillus might partially account for treatment failures. Recent advances in our understanding of mechanisms of antifungal drug action in Aspergillus, along with the standardization of in vitro susceptibility testing methods, has brought resistance testing to the forefront of clinical mycology. In addition, molecular biology has started to shed light on the mechanisms of resistance of A. fumigatus to azoles and the echinocandins, while genome-based assays show promise for high-throughput screening for genotypic antifungal resistance. Several problems remain, however, in the study of this complex area. Large multicenter clinical studies--point prevalence or longitudinal--to capture the incidence and prevalence of antifungal resistance in A. fumigatus isolates are lacking. Correlation of in vitro susceptibility with clinical outcome and susceptibility breakpoints has not been established. In addition, the issue of cross-resistance between the newer triazoles is of concern. Furthermore, in vitro resistance testing for polyenes and echinocandins is difficult, and their mechanisms of resistance are largely unknown. This review examines challenges in the diagnosis, epidemiology, and mechanisms of antifungal drug resistance in A. fumigatus.

Caspofungin treatment in severely ill, immunocompromised patients: a case-documentation study of 118 patients

BACKGROUND

Caspofungin has shown efficacy in empirical antifungal therapy in neutropenic patients, refractory invasive Aspergillus infections and invasive candidiasis. Here we report the currently largest series of patients treated with caspofungin outside clinical trials.

METHODS

Centres in Germany that were known to treat patients with invasive fungal infections were asked to fill out detailed questionnaires for all patients treated with caspofungin. No effort was made to influence the decision to use caspofungin.

RESULTS

A total of 118 patients were evaluable (median age 48 years, interquartile range 38-58), out of which 41 (35%) suffered from acute leukaemia, 31 (26%) had allogeneic stem cell transplants, 16 (14%) lymphoma or myeloma, 8 (7%) autologous stem cell transplants and 22 (19%) other causes for immunosuppression. One hundred and six patients were evaluable for efficacy out of which 68 (64%) patients achieved a complete or partial remission. A total of 81 out of 115 (70%) patients were alive 30 days after the end of caspofungin therapy. Response rates were similar in proven (20/32, 63%) and probable (27/46, 59%) infections, in neutropenic patients (41/55, 75%) and in patients who were (44/70, 63%) or were not (24/36, 67%) refractory to antifungal pre-treatment. The response rate in mechanically ventilated patients was 29% (7/24). Caspofungin was well tolerated, even in 14 patients, who were concomitantly treated with ciclosporin A, no drug-related elevations of bilirubin, alanine aminotransferase or creatinine were found.

CONCLUSIONS

This open case study of severely ill patients with invasive fungal infections demonstrates both excellent efficacy and very low toxicity of caspofungin.

[In vitro susceptibility of fungal and yeast clinical isolates to itraconazole and voriconazole]

The interest on the in vitro susceptibility to itraconazole has recently increased due the availability of the intravenous formulation. In this study, comparative MICs of this antifungal with voriconazole were carried out in 62 clinical isolates of filamentous fungi and 100 yeasts isolates using the NCCLS microbroth methods described in M38-A and M27-A2 documents. A MIC90 of 0.125 micrograms per ml was observed for itraconazole and voriconazole against Aspergillus fumigatus. Higher susceptibility to itraconazole was found for the filamentous form of Sporotrhix schenckii (p = 0.001). Voriconazole was more effective against Scedosporium apiospermium while Scedosporium prolificans isolates were resistant to both azoles. Some isolates of Rhizopus stolonifer were susceptible to itraconazole and resistant to voriconazole, but without statistical significance. Susceptibility of nine species of Candida was similar for both triazoles used in this study. However, Candida glabrata was more susceptible to voriconazole. Some fluconazole-resistant Candida albicans isolates were susceptible to itraconazole and / or voriconazole. Cryptococcus neoformans was more susceptible to itraconazole than to voriconazole. Itraconazole and voriconazole showed very close in vitro activity against the tested fungal isolated, except against S. schenckii. In spite of this, there were some differences in susceptibility among isolates within the same fungal species.

Economic evaluation of voriconazole in the treatment of invasive aspergillosis in the Netherlands

OBJECTIVE

To asses the cost-effectiveness of voriconazole in comparison to conventional amphotericin B and itraconazole for the treatment of invasive aspergillosis in the Netherlands.

METHODS

The cost-effectiveness of voriconazole in comparison to conventional amphotericin B or itraconazole was evaluated with a decision tree model followed by a life-time Markov model, focusing on long-term survival of patients treated for invasive aspergillosis. Efficacy after 12 weeks of treatment from clinical trials was used to estimate long-term effectiveness by extrapolating these short-term results over time. Information on medical resource consumption, treatment pathways and switch proportions were obtained from both the literature and Experts. Probabilistic analysis was used to compare the cost-effectiveness among the regimens.

RESULTS

With voriconazole, the mean cost for treating invasive aspergillosis per patient was E32 651 (2.5th percentile and 97.5th of uncertainty distribution: E30 037; E36 859), compared to E33 616 (E30 920; E39 633) for conventional amphotericin B and E29 115 (E23 537; E61 414) for itraconazole. The mean survival of patients treated with voriconazole was 174.0 life weeks (160.1; 188.8), compared to 116.1 life weeks (104.8; 128.0) for conventional amphotericin B and 150.4 life weeks (109.1; 194.4) for itraconazole. The beneficial effects of voriconazole on both cost and effectiveness compared with conventional amphotericin B resulted in a probability of 69.8% that voriconazole was a dominant treatment (i.e. less costs and longer survival). The incremental cost-effectiveness ratio of voriconazole versus itraconazole was E150 per life week (i.e. 7800 euros per life-year gained). Depending on the willingness to pay (WTP) the probability of being cost-effective vs. itraconazole increased to a maximum probability of 70%.

CONCLUSION

In the treatment of invasive aspergillosis, voriconazole is dominant over amphotericin B and cost-effective in comparison to itraconazole.

Advances and challenges in management of invasive mycoses

Invasive mycoses pose a major diagnostic and therapeutic challenge. Advances in antifungal agents and diagnostic methods offer the potential for improved outcomes in patients with these infections, which are often lethal. Many fungal pathogens occur almost exclusively in opportunistic settings--in the immunocompromised host--and these infections are the focus of this review. Several areas of ongoing challenge remain, including the emergence of resistant organisms and the absence of reliable markers for early identification of patients at risk of developing invasive fungal disease. This Seminar reviews the changing epidemiology of invasive mycoses, new diagnostic methods, and recent therapeutic options and current management strategies for these opportunistic pathogens.

Clinical Pharmacokinetic Monitoring of Itraconazole Is Warranted in Only a Subset of Patients

Itraconazole is a synthetic triazole antifungal agent that is commonly used in the prophylaxis and treatment of fungal infection. A role for itraconazole drug monitoring has been suggested previously; however, the advent of new formulations and increased clinical evidence may aid in further defining this role. Consequently, we have used a previously published decision-making algorithm to determine whether clinical pharmacokinetic monitoring of itraconazole is warranted. First, itraconazole has proven efficacy for the prophylaxis and treatment of fungal infection in immunocompromised individuals such as neutropenic cancer, human immunodeficiency virus (HIV), and solid organ transplant patients. Several assays have been developed to quantify itraconazole and its main metabolite in patient plasma. Measurement of these plasma drug levels in many clinical studies has resulted in no clear definition of a relationship between concentration and efficacy. However, limited evidence suggests a correlation between itraconazole levels greater than 250 or 500 ng/mL and increased efficacy. Clinical monitoring of efficacy is difficult because of the challenges in diagnosis of fungal infections and nonspecific clinical symptoms associated with fungal infections. Pharmacokinetic studies of itraconazole indicate that significant inter- and intrapatient variability exists in both healthy and immunocompromised patient populations, although subpopulations such as neutropenic cancer and HIV patients appear to require more drug than their healthy counterparts to attain similar drug levels. A therapeutic range has not been defined for itraconazole, but because of its relatively minimal side effects, a narrow range is unlikely. Drug interactions can occur with itraconazole because it is both an inhibitor and substrate of the cytochrome P450 3A4 (CYP3A4) enzyme and P-glycoprotein transporter systems. Protein binding alterations could also lead to differences in drug effect. Last, the duration of treatment of prophylaxis is significantly long to propose a potential benefit from drug monitoring. From weighing the available evidence, it appears that itraconazole drug level monitoring would provide more information on efficacy than clinical judgment alone in a subset of patients. Immunosuppressed patients requiring preventative therapy who have suspected poor absorption, are on concomitant enzyme inducers, or are suspected to be noncompliant would have the greatest benefit from itraconazole drug monitoring.

Adverse effects of antifungal therapies in invasive fungal infections: review and meta-analysis

Amphotericin B is the main therapeutic agent for the treatment of invasive fungal infections; however, it is associated with significant toxicities that limit its use. Other systemic antifungal agents have been developed to improve tolerability while maintaining the efficacy profile of conventional amphotericin B. Fifty-four studies involving 9,228 patients were assessed for the frequency of adverse effects of the main systemic antifungal agents. While the results suggest that liposomal amphotericin B (L-AmB) is the least nephrotoxic of the lipid formulations (14.6%), that conventional amphotericin B (AmB) is the most nephrotoxic (33.2%), and that itraconazole is the most hepatotoxic (31.5%), the lack of standard definitions of antifungal-related adverse effects limits the validity of these results. Furthermore, heterogeneous patient pools and differing protocols make it difficult to draw direct comparisons between studies. With the advent of newer classes of systemic antifungal agents, future trials should conform to definitions that are universally applicable and clinically relevant to allow for such comparisons and to enable evidence-based decision-making.

Prise en charge diagnostique et thérapeutique des infections à Aspergillus sp. chez le patient immunodéprimé. Recommandations du CHRU de Lille — version 4 — novembre 2004

Invasive aspergillosis is a severe complication in immunocompromised patients. The arrival of new antifungal agents motivated the redaction of guidelines, regularly updated, by a Lille University hospital multidisciplinary task force. These guidelines assess diagnostic and therapeutic issues. The main recommended diagnosis tool is the chest CT scan, ordered at the smallest suspicion and, also, measure of the blood and broncho alveolar lavage fluid galactomannan. Treatment guidelines assess prophylaxis, empirical and documented therapy. Primary prophylaxis is warranted in only two cases, pulmonary graft or stem cell transplant in patients with chronic GVH and receiving corticosteroids. Empirical therapy should use one of the available amphotericin B formulations, chosen according to the patient history. Caspofungin is another choice. Documented therapy, depending on presentation, can be a single drug or a combination. First line therapy for single drug is i.v. voriconazole. Lipid formulations of amphotericin B are another choice. A combination therapy can be used as a first line treatment, for multiple lesions, or as salvage therapy. It must include caspofungin, associated with liposomal amphotericin B or voriconazole. A tight cooperation with thoracic surgeons is recommended.

Pharmacological agents in development for invasive aspergillosis

The urgent medical need for new potent antifungal agents in the management of invasive aspergillosis (IA) has resulted in the development of several compounds which may be of value in the future for the treatment or prophylaxis of IA. In the past years, several novel types of drugs have been discovered and developed, some of which are already in late-stage clinical trials and ready to enter the market. This paper discusses the antifungal agents, classified by their mode of action, that are currently available and the agents which are still in development for treatment or prevention of IA.

New agents for the treatment of systemic fungal infections – current status

Systemic antifungal chemotherapy is enjoying its most dynamic era. More antifungal agents are under development than ever before, including agents in entirely new classes. Major goals of current investigations are to identify compounds with a wide spectrum of activity, minimal toxicity and a high degree of target specificity. The antifungal drugs in development include new azoles {voriconazole, posaconazole (formerly SCH-56592), ravuconazole (formerly BMS-207147)}, lipid formulations of amphotericin B, a lipid formulation of nystatin, echinocandins {anidulafungin (formerly, LY-303366, VER-002), caspofungin (formerly MK-991), micafungin (formerly FK-463)}, antifungal peptides other than echinocandins, and sordarin derivatives. This discussion reviews the currently available antifungal agents and summarises the developmental issues that surround these new systemic antifungal drugs.

Efficacy of posaconazole in a murine model of central nervous system aspergillosis

Human central nervous system (CNS) aspergillosis has >90% mortality. We compared posaconazole with other antifungals for efficacy against murine CNS aspergillosis. All tested regimens of posaconazole were equivalent to those of amphotericin B and superior in prolonging survival and reducing CFU to those of itraconazole and caspofungin and to vehicle controls. No antifungal regimen effected cure. No toxicity was noted. Overall, posaconazole shows potential for treating CNS aspergillosis.

Efficacy and safety of caspofungin for treatment of invasive aspergillosis in patients refractory to or intolerant of conventional antifungal therapy

BACKGROUND

Invasive aspergillosis (IA) is an important cause of morbidity and mortality among immunocompromised patients. Echinocandins are novel antifungal molecules with in vitro and in vivo activity against Aspergillus species.

METHODS

We investigated the efficacy and safety of caspofungin in the treatment of IA. Ninety patients with IA who were refractory to or intolerant of amphotericin B, lipid formulations of amphotericin B, or triazoles were enrolled to receive caspofungin.

RESULTS

Efficacy was assessed for 83 patients who had infection consistent with definitions of IA and who received >or=1 dose of study drug. Common underlying conditions included hematologic malignancy (48% of patients), allogeneic blood and marrow transplantation (25% of patients), and solid-organ transplantation (11% of patients). Seventy-one patients (86%) were refractory to and 12 patients (14%) were intolerant of previous therapy. A favorable response to caspofungin therapy was observed in 37 (45%) of 83 patients, including 32 (50%) of 64 with pulmonary aspergillosis and 3 (23%) of 13 with disseminated aspergillosis. Two patients discontinued caspofungin therapy because of drug-related adverse events. Drug-related nephrotoxicity and hepatotoxicity occurred infrequently.

CONCLUSION

Caspofungin demonstrated usefulness in the salvage treatment of IA.

Update on antifungal treatment of invasive Candida and Aspergillus infections. Derzeitiger Kenntnisstand in der antimykotischen Behandlung invasiver Candida- und Aspergillus-Infektionen

Invasive Candida and Aspergillus infections are among the most common serious complications occurring in chronically immunosuppressed patients, in particular those with hematological malignancies and transplant recipients. A rational, early systemic antifungal treatment can be based upon imaging diagnostic techniques as well as upon conventional mycological and non-culture-based procedures. The availability of well tolerable and highly efficacious systemic antifungals has improved the spectrum of therapeutic options and the success rates of antifungal treatment. However, with respect to high treatment costs associated with these new agents, it is mandatory to specify indications and limitations for the use of these substances. Voriconazole may well become the new standard primary treatment of invasive aspergillosis. The role of the new echinocandins such as caspofungin, which has recently been approved for salvage treatment of resistant and refractory Aspergillus infections, in primary or combination treatment of invasive aspergillosis must be further studied. Caspofungin is at least as effective as, yet significantly better tolerated than amphotericin B for primary treatment of invasive candidosis in non-neutropenic patients, and has been approved for this indication. The selection of systemic antifungals in patients with invasive Candida infection critically depends upon the identification of Candida species involved, because some non-albicans Candida spp. are resistant to azole antifungals.

Voriconazole-a new therapeutic agent with an extended spectrum of antifungal activity

Voriconazole is a new antifungal agent that can be given orally and intravenously. It has proven efficacy for treating candidosis and invasive aspergillosis as well as other mould infections, such as those caused by Fusarium and Scedosporium spp. The drug is generally well tolerated.

Invasive aspergillosis in patients with hematologic malignancies

Invasive aspergillosis is an increasingly common and often fatal opportunistic fungal infection in patients with hematologic malignancies. Prolonged and profound neutropenia remains a key risk factor for the development of invasive aspergillosis. However, qualitative deficiencies in host immune responses resulting from prolonged corticosteroid therapy, graft-versus-host disease, and cytomegalovirus infection are important risk factors for the recurrence and progression of Aspergillus infections after bone marrow recovery. Early diagnosis of invasive aspergillosis remains a challenge, and few tools are available for monitoring its course once the diagnosis is established. Even with the recent introduction of new antifungal therapies, mortality in patients with invasive aspergillosis remains high, and uniformly effective prophylaxis or preemptive therapeutic strategies are lacking. Strategies such as combination antifungal therapy and immunotherapy often are used as first-line treatment approaches in patients with documented invasive aspergillosis despite a paucity of clinical trial data. Recent advances in our understanding of the epidemiology, pathogenesis, and treatment of invasive aspergillosis in patients with hematologic malignancies are reviewed. The problems and controversies associated with defining optimal treatment strategies for invasive aspergillosis in this heavily immunocompromised population are highlighted.

New and emerging antifungal agents: impact on respiratory infections

Fungal pathogens are increasingly important causes of respiratory disease, yet the number of antifungal agents available for clinical use is limited. Use of amphotericin B deoxycholate is hampered by severe toxicity. Triazole agents currently available have significant drug interactions; fluconazole has a limited spectrum of activity and itraconazole was, until recently, available only in oral formulations with limited bioavailability. The development of resistance to all three agents is increasingly being recognized and some filamentous fungi are resistant to the action of all of these agents. In the past few years, new antifungal agents and new formulations of existing agents have become available.The use of liposomal amphotericin B preparations is associated with reduced, but still substantial, rates of nephrotoxicity and infusion-related reactions. An intravenous formulation of itraconazole has been introduced, and several new triazole agents have been developed, with the view of identifying agents that have enhanced potency, broader spectra of action and improved pharmacodynamic properties. One of these, voriconazole, has completed large-scale clinical trials. In addition, caspofungin, the first of a new class of agents, the echinocandins, which inhibit cell wall glucan synthesis, was approved for use in the US in 2001 as salvage therapy for invasive aspergillosis. It is hoped that the availability of these agents will have a significant impact on the morbidity and mortality of fungal respiratory infections. However, at the present time, our ability to assess their impact is limited by the problematic nature of conducting trials for antifungal therapy.

Treatment of opportunistic mycoses: how long is long enough?

For most opportunistic mycoses no optimum duration of antifungal therapy has been defined. Although a long course of therapy is prudent, especially for mycelial fungal infections, excessively and unnecessarily extended courses of treatment incur a risk of toxicity and the expense of the therapeutic regimen. On the basis of existing reports on the pathogenesis and the effect of duration of therapy and other variables on outcome and response rate in fungal infections, this review proposes guidelines that may facilitate a rational approach to decision-making about the duration of antifungal therapy.

Treatment of fungal infections in hematology and oncology--guidelines of the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Oncology (DGHO)

The Infectious Diseases Working Party of the German Society of Haematology and Oncology presents their guidelines for the treatment of fungal infections in patients with hematological and oncological malignancies. These guidelines are evidence-based, considering study results, case reports and expert opinions, using the evidence criteria of the Infectious Diseases Society of America (IDSA). The recommendations for major fungal complications in this setting are summarized here. The primary choice of therapy for chronic candidiasis should be fluconazole, reserving caspofungin or amphotericin B (AmB) for use in case of progression of the Candida infection. Patients with candidemia (except C. krusei or C. glabrata) who are in a clinically stable condition without previous azole prophylaxis should receive fluconazole, otherwise AmB or caspofungin. Voriconazole is recommended for the first-line treatment of invasive aspergillosis. The benefit of a combination of AmB and 5-flucytosine has not been demonstrated except in patients with cryptococcal meningitis. Mucormycosis is relatively rare. The drug therapy of choice consists of AmB, desoxycholate or liposomal formulation, in the highest tolerable dosage. Additional surgical intervention has been shown to achieve a lower fatality rate than with antifungal therapy alone. The role of interventional strategies, cytokines/G-CSF, and granulocyte transfusions in invasive fungal infections are further reviewed. These guidelines offer actual standards and discussions on the treatment of oropharyngeal and esophageal candidiasis, invasive candidiasis, cryptococcosis and mould infections.

Determination of itraconazole and hydroxyitraconazole in plasma by use of liquid chromatography-tandem mass spectrometry with on-line solid-phase extraction

In this paper a method for the simultaneous quantification of the anti-fungal drug itraconazole and its co-active metabolite hydroxyitraconazole in plasma employing liquid chromatography tandem-mass spectrometry and automated solid-phase extraction is described. The method proved rugged, enables short turn-around times and is highly specific. Since there is growing evidence for the importance of therapeutic drug monitoring of itraconazole in the prophylaxis and treatment of invasive fungal infections, the method described here is of interest for a large number of tertiary care hospital laboratories.

Itraconazole--perspectives for the management of invasive aspergillosis

Itraconazole has become an important option in the management of invasive aspergillosis. The compound has potent and broad spectrum antifungal activity in vitro against Aspergillus spp. with a species- and strain dependent fungicidal mode of action. In vivo, the antifungal efficacy of itraconazole has been demonstrated in several non-immunocompromised and immunocompromised animal models of disseminated and invasive pulmonary aspergillosis. Itraconazole is available in oral and intravenous formulations, displays non-linear plasma pharmacokinetics, and is usually well tolerated. Non-comparative clinical data of itraconazole for therapy of suspected or proven invasive aspergillosis suggest response rates similar to those of conventional amphotericin B; however, the experience with itraconazole for induction therapy of invasive aspergillosis is limited, particularly in profoundly neutropenic patients. Itraconazole has an important role for consolidation and maintenance therapy of patients with invasive aspergillosis, and novel combination therapies involving itraconazole are currently under intensive preclinical investigation as to their usefulness for primary therapy.

Itraconazole to prevent fungal infections in chronic granulomatous disease

BACKGROUND

Chronic granulomatous disease is a rare disorder in which the phagocytes fail to produce hydrogen peroxide. The patients are predisposed to bacterial and fungal infections. Prophylactic antibiotics and interferon gamma have reduced bacterial infections, but there is also the danger of life-threatening fungal infections. We assessed the efficacy of itraconazole as prophylaxis against serious fungal infections in chronic granulomatous disease.

METHODS

Thirty-nine patients at least 5 years old (6 female and 33 male; mean age, 14.9 years) were enrolled in a randomized, double-blind, placebo-controlled study. After the initially assigned treatment, each patient alternated between itraconazole and placebo annually. Patients 13 years of age or older and all patients weighing at least 50 kg received a single dose of 200 mg of itraconazole per day; those less than 13 years old or weighing less than 50 kg received a single dose of 100 mg per day. The primary end point was severe fungal infection, as determined by histologic results or culture.

RESULTS

One patient (who had not been compliant with the treatment) had a serious fungal infection while receiving itraconazole, as compared with seven who had a serious fungal infection while receiving placebo (P=0.10). No patient receiving itraconazole but five patients receiving placebo had a superficial fungal infection. No serious toxic effects were noted, although one patient had a rash and another had elevated results on liver-function tests; both of these effects resolved with the discontinuation of itraconazole.

CONCLUSIONS

Itraconazole prophylaxis appears to be an effective and well-tolerated treatment that reduces the frequency of fungal infections in chronic granulomatous disease, but monitoring for long-term toxic effects is warranted.

Antifungal therapy--state of the art at the beginning of the 21st century

The most relevant information on the present state of the art of antifungal chemotherapy is reviewed in this chapter. For dermatomycoses a variety of topical antifungals are available, and safe and efficacious systemic treatment, especially with the fungicidal drug terbinafine, is possible. The duration of treatment can be drastically reduced. Substantial progress in the armamentarium of drugs for invasive fungal infections has been made, and a new class of antifungals, echinocandins, is now in clinical use. The following drugs in oral and/or intravenous formulations are available: the broad spectrum polyene amphotericin B with its new "clothes"; the sterol biosynthesis inhibitors fluconazole, itraconazole, and voriconazole; the glucan synthase inhibitor caspofungin; and the combination partner flucytosine. New therapy schedules have been studied; combination therapy has found a significant place in the treatment of severely compromised patients, and the field of prevention and empiric therapy is fast moving. Guidelines exist nowadays for the treatment of various fungal diseases and maintenance therapy. New approaches interfering with host defenses or pathogenicity of fungal cells are being investigated, and molecular biologists are looking for new targets studying the genomics of pathogenic fungi.

Systemic mycoses in the immunocompromised host: an update in antifungal therapy

Despite significant advances in the management of immunosuppressed patients, invasive fungal infections remain an important life-threatening complication. In the last decade several new antifungal agents, including compounds in pre-existing classes (new generation of triazoles, polyenes in lipid formulations) and novel classes of antifungals with a unique mechanism of action (echinocandins), have been introduced in clinical practice. Ongoing and future studies will determine their exact role in the management of different mycoses. The acceleration of antifungal drug discovery offers promise for the management of these difficult to treat opportunistic infections.

Clinical pharmacology of antifungal compounds

Prompted by the worldwide surge in fungal infections, the past decade has witnessed a considerable expansion in antifungal drug research. New compounds have entered the clinical arena, and major progress has been made in defining paradigms of antifungal therapies. This article provides an up-to-date review on the clinical pharmacology, indications, and dosage recommendations of approved and currently investigational therapeutics for treatment of invasive fungal infections in adult and pediatric patients.

Antifungal pharmacotherapy for invasive mould infections

The incidence of invasive mould infections is increasing and is associated with significant morbidity and mortality. Among the most prevalent of these infections are those caused by Aspergillus and Fusarium species. Invasive disease caused by moulds frequently presents as a pulmonary infection, but haematogenous infection can occur. Some moulds cause cutaneous disease through either direct inoculation of the skin or secondary spread to the skin after dissemination from another body site. Early diagnosis can often be difficult and, unfortunately, diagnosis occurs late in the course of illness in many cases. Treatment options have historically been limited by the need for intravenous administration (amphotericin B), significant toxicities (amphotericin B), lack of reliable in vitro activity (e.g., amphotericin B in Fusarium and Scedosporium apiospermum infections) and relative lack of clinical experience with newer agents. The recent approval of voriconazole (Vfend, Pfizer) introduces a treatment option that demonstrates both in vitro and in vivo activity against a variety of moulds. With the recent development of the new echinocandin class of antifungal agents and newer broad-spectrum azole antifungal agents with in vitro mould activity, there is a renewed emphasis on fungal treatment strategies. Antimould therapy presents challenges in adverse effect avoidance and management, drug interactions and pharmacoeconomic considerations. Furthermore, combination therapy is being explored with these various new antifungal agents. The administration of an optimal fungicidal therapy early in the course of the illness and control of the underlying disease are vital to prevent complications and mortality from these tenacious mycoses.

Arthritis and osteomyelitis due to Aspergillus fumigatus: a 17 years old boy with chronic granulomatous disease

BACKGROUND

Invasive Aspergillus infections are frequently seen in immunocompromised patients but arthritis is a rare complication of Aspergillus infections in the absence of immune suppressive therapy, trauma or surgical intervention.

CASE PRESENTATION

A 17 years old male patient with arthritis and patellar osteomyelitis of the left knee whose further investigations revealed chronic granulomatous disease as the underlying disease is followed. Aspergillus fumigatus was isolated from the synovial fluid and the tissue samples cultures. He was treated with Amphotericin B deoxicolate 0.7 mg/kg/day. Also surgical debridement was performed our patient. Amphotericin B nephrotoxicity developed and the therapy switched to itraconazole 400 mg/day. Itraconazole therapy were discontinued at the 6th month. He can perform all the activities of daily living including.

CONCLUSION

We think that, chronic granulomatous disease should be investigated in patients who have aspergillar arthritis and osteomyelitis.

Antifúngicos de uso sistémico

Invasive fungal infection is the infectious complication with highest associated mortality. Until the 90's amphotericin B was the only drug available to treat these infections. Its spectrum of antifungal activity is excellent, but its use is associated with toxicity in many cases. The development of amphotericin B lipid formulations has resulted in a significant decrease in most of the side effects associated with this drug. Triazoles are safe and effective for treating most invasive fungal infections. Fluconazole is an excellent drug for the prevention and treatment of Candida and Cryptococcus infections, itraconazole has good activity against Candida and Aspergillus, and voriconazole has shown to be better than amphotericin B for invasive aspergillosis. Caspofungin belongs to a new group of antifungal agents, the echinocandins, which are very safe and present excellent activity against Candida and Aspergillus.

Current treatment options for chronic granulomatous disease

Chronic granulomatous disease is a rare inherited disorder of phagocytic cells which results in a susceptibility to infections of catalase-positive bacteria and fungi (especially Aspergillus species), as well as granuloma formation. The mainstay of therapy is antibacterial and antifungal prophylaxis. Trimethoprim sulfamethoxazole is the drug of choice for the prevention of bacterial infection, while itraconazole is most widely used for the prevention of fungal infection. Immunomodulatory agents, such as IFN-phi, have a role in the prevention and treatment of intractable infection. New antifungal agents provide the promise of improved cure rates for invasive Aspergillus, while bone marrow transplants and gene therapy may offer the promise of complete cure.