A randomized comparison of fluconazole with amphotericin B as empiric anti-fungal agents in cancer patients with prolonged fever and neutropenia

Clinical hepatotoxicity associated with antifungal agents

INTRODUCTION

Invasive fungal diseases (IFDs) are a leading cause of morbidity and mortality among immunocompromised patients with bone marrow failure syndromes, hematological malignancies, hematopoietic stem cell transplantation (HSCT), those admitted in intensive care units (ICUs) and those with prolonged febrile neutropenia. IFDs occur in a setting of multiple morbidities and are associated with case fatality rates between 30 and 70%. Along with the development of classes and compounds, the last two decades have seen substantial improvements in the prevention and management of these infections and an overall increased use of antifungal agents. Areas covered: All antifungal agents, including amphotericin B formulations, echinocandins and the triazoles, may cause hepatic toxicity that ranges from mild and asymptomatic abnormalities in liver function tests to substantial liver injury and fulminant hepatic failure. Expert opinion: The present article reviews incidence and severity of hepatotoxicity associated with different classes and agents to provide a better understanding of this specific end organ toxicity and safer use of antifungal agents A thorough understanding of the distribution, metabolism, elimination and drug-drug interactions of antifungal agents used for management of IFDs in combination with safety data from clinical trials, pharmacokinetic and pharmacodynamic studies may guide the use of antifungal treatment in patients at high risk for the development of hepatic dysfunction and in those with underlying liver damage due to cytotoxic therapy.

Antifungal Therapy in Hematopoietic Stem Cell Transplant Recipients

Invasive fungal infections (IFI) represent a major hindrance to the success of hematopoietic stem cell transplantation (HSCT), contributing substantially to morbidity and infection-related mortality. During the most recent years several reports indicate an overall increase of IFI among hematologic patients, in particular, invasive aspergillosis, that may be explained, at least partially, by the fact that diagnoses only suspected in the past, are now more easily established due to the application of serum biomarkers and early use of CT scan. Along with new diagnostic options, comes the recent development of novel antifungal agents that expanded the spectrum of activity over traditional treatments contributing to the successful management of fungal diseases. When introduced in 1959, Amphotericin B deoxycholate (d-AmB) was a life-saving drug, and the clinical experience over 50 years has proven that this compound is effective although toxic. Given the superior safety profile, lipid formulations of AmB have now replaced d-AmB in many circumstances. Similarly, echinocandins have been investigated as initial therapy for IA in several clinical trials including HSCT recipients, although the results were moderately disappointing leading to a lower grade of recommendation in the majority of published guidelines. Azoles represent the backbone of therapy for treating immunocompromised patients with IFI, including voriconazole and the newcomer isavuconazole; in addition, large studies support the use of mold-active azoles, namely voriconazole and posaconazole, as antifungal prophylaxis in HSCT recipients.

The aim of the present review is to summarize the clinical application of antifungal agents most commonly employed in the treatment of IFI.

Clinical effects of topical antifungal therapy in chronic rhinosinusitis: a randomized, double-blind, placebo-controlled trial of intranasal fluconazole

Several studies have been in favor of fungi as a possible pathogenesis of chronic rhinosinusitis (CRS); however, to date, there is no scientific consensus about the use of antifungal agents in disease management. The aim of the present study was to investigate the efficacy of intranasal fluconazole in improving disease symptoms and objective outcomes of patients with CRS. A randomized, double-blind, placebo-controlled study was conducted on 54 patients who were diagnosed with CRS and had not been responsive to routine medical treatments. They were randomly assigned to receive either fluconazole nasal drop 0.2 % or placebo in addition to the standard regimen for a duration of 8 weeks. Patients' outcomes were evaluated according to Sino-Nasal Outcome Test 20 (SNOT-20), endoscopic scores, and Computed Tomography (CT) scores. No statistically significant difference was found in SNOT-20 (p = 0.201), endoscopic (p = 0.283), and CT scores (p = 0.212) of the patients at baseline and after 8-week course of treatment between drug and placebo group. Similar to many studies, the use of topical antifungal treatment for patients with CRS was not shown to be significantly effective. However, further studies are needed to obtain high levels of consistent evidence in order to arrive at a decision whether antifungal therapy is effective in management of CRS or not.

Amphotericin B versus fluconazole for controlling fungal infections in neutropenic cancer patients

BACKGROUND

Systemic fungal infection is considered to be an important cause of morbidity and mortality in cancer patients, particularly those with neutropenia. Antifungal drugs are often given prophylactically, or empirically to patients with persistent fever.

OBJECTIVES

To compare the effect of fluconazole and amphotericin B on morbidity and mortality in patients with cancer complicated by neutropenia.

SEARCH METHODS

We searched PubMed from 1966 to 7 July 2014 and the reference lists of identified articles.

SELECTION CRITERIA

Randomised clinical trials comparing fluconazole with amphotericin B.

DATA COLLECTION AND ANALYSIS

The two review authors independently assessed trial eligibility and risk of bias, and abstracted data.

MAIN RESULTS

Seventeen trials (3798 patients, 381 deaths) were included. In two large three-armed trials, results for amphotericin B were combined with results for nystatin in a 'polyene' group. Because nystatin is an ineffective drug in these circumstances, this approach creates a bias in favour of fluconazole. Furthermore, most patients were randomised to oral amphotericin B, which is poorly absorbed and poorly documented. There was overlap among the 'polyene' trials but we were unable to obtain any information from the trial authors or from Pfizer, the manufacturer of fluconazole, to clarify these issues. There were no significant differences in effect between fluconazole and amphotericin B, but the confidence intervals were wide. More patients dropped out of the study when they received amphotericin B, but as none of the trials were blinded decisions on premature interruption of therapy could have been biased. Furthermore, amphotericin B was not given under optimal circumstances, with premedication to reduce infusion-related toxicity, slow infusion, and with fluid, potassium and magnesium supplements to prevent nephrotoxicity. The major harms were hepatic impairment and gastrointestinal adverse effects with fluconazole and infusion-related toxicity, renal impairment and gastrointestinal adverse effects with amphotericin B. For the 2011 and 2014 updates no additional trials were identified for inclusion.

AUTHORS' CONCLUSIONS

Amphotericin B has been disfavoured in several of the trials through their design or analysis, or both. Since intravenous amphotericin B is the only antifungal agent for which an effect on mortality has been shown, and since it is considerably cheaper than fluconazole, it should be the preferred agent.

Fluconazole for the treatment of candidiasis: 15 years experience

Candidia spp. are responsible for contributing to the increasing global prevalence of fungal infections. Fluconazole (Diflucan((R)), Pfizer) is a triazole that has established an exceptional therapeutic record for candida infections including oropharyngeal and esophageal candidiasis, vulvovaginal candidiasis, candidemia and disseminated candidiasis. It is both an oral and parenteral fungistatic agent that inhibits ergosterol synthesis in yeasts. Extensive clinical studies have demonstrated fluconazole's remarkable efficacy, favorable pharmacokinetics and reassuring safety profile, all of which have contributed to its widespread use. Fluconazole became the first antifungal with worldwide sales exceeding billions of dollars, therefore providing an incentive for the pharmaceutical industry to develop new antifungals. This review will examine the contributions and limitations of fluconazole in the treatment of superficial and invasive candidiasis syndromes.

Luminescent-activated transfected killer cells to monitor leukocyte trafficking during systemic bacterial and fungal infection

BACKGROUND

Activated transfected killer (ATAK) cells are immortal phagocytes transfected with a luminescence reporter that effectively treat lethal infections in neutropenic mice. Their in vivo trafficking, lifespan, and immunogenicity are unknown.

METHODS

Mice were made neutropenic; infected or not with Staphylococcus aureus, Acinetobacter baumannii, Candida albicans, or Aspergillus fumigatus; and treated intraperitoneally with ATAK cells. Cell trafficking and lifespan were assessed by in vivo imaging and reverse transcription-polymerase chain reaction.

RESULTS

In uninfected neutropenic mice, ATAK cells spread from the mesentery into visceral organs on days 1-3. Splenic accumulation of ATAK cells increased at day 1 after infection with S. aureus and A. baumannii, and kidney accumulation increased in mice infected with C. albicans. Lung accumulation was seen at day 3 in mice infected by inhalation with A. fumigatus. By day 8, coincident with increasing anti-ATAK antibodies, luminescence signal was lost and there was no detectable mRNA transcription from ATAK cells.

CONCLUSIONS

ATAK cells accumulated in target organs with distinct profiles, depending on the microbial etiology of infection. Finally, generation of an anti-ATAK immune response may provide an important safety mechanism that helps clear the cells from the host as the marrow recovers.

Fluconazole loading dose pharmacokinetics and safety in infants

BACKGROUND

Invasive candidiasis is a leading cause of morbidity and mortality in critically ill infants. Prompt administration of fluconazole and achievement of the therapeutic target (area under the curve 0 to 24 hours >400 mg*h/L) improve outcomes in candidemic patients. A loading dose of fluconazole is advised for older patients but has not been evaluated in infants. We sought to determine the pharmacokinetics and safety of a fluconazole loading dose in infants at risk for invasive fungal infection.

METHODS

We enrolled 10 hospitalized infants <60 days old with suspected systemic fungal infection in this open-label study; 9 received a 25-mg/kg fluconazole loading dose followed by a maintenance dose of 12 mg/kg every 24 hours for 4 additional days. Plasma samples were obtained following the loading and steady-state doses (doses 3-5). We used a 1-compartment model to fit the data to estimate pharmacokinetic indices.

RESULTS

Data from 57 drug concentrations obtained from 8 infants (median postnatal age, 16 days [interquartile range, 13-32] and median gestational age, 37 weeks [35-38]) showed that the median fluconazole area under the curve 0 to 24 hours (mg*h/L) in this population was 479 (347-496). Of the 8 infants who received the loading dose, 5 (63%) achieved the therapeutic target on the first day of dosing, and all infants achieved a fluconazole 24-hour trough concentration >8 μg/mL. No adverse events were thought to be related to fluconazole therapy.

CONCLUSIONS

A loading dose of fluconazole (25 mg/kg) was safe in this small cohort of young infants and achieved the therapeutic target more rapidly than traditional dosing.

Systematic review and meta-analysis of the tolerability and hepatotoxicity of antifungals in empirical and definitive therapy for invasive fungal infection

To evaluate the tolerability and liver safety profiles of the systemic antifungal agents commonly used for the treatment of invasive fungal infection, we conducted a systematic review and meta-analysis of randomized controlled trials published before 31 August 2009. Two reviewers independently applied selection criteria, performed quality assessment, and extracted data. We used the beta-binomial model to account for variation across studies and the maximum likelihood method to estimate the pooled risks. We identified 39 studies with more than 8,000 enrolled patients for planned comparisons. The incidence rates of treatment discontinuation due to adverse reactions and liver injury associated with antifungal therapy ranged widely. The pooled risks of treatment discontinuation due to adverse reactions were above 10% for amphotericin B formulations and itraconazole, whereas they were 2.5% to 3.8% for fluconazole, caspofungin, and micafungin. We found that 1.5% of the patients stopped itraconazole treatment due to hepatotoxicity. Furthermore, 19.7% of voriconazole users and 17.4% of itraconazole users had elevated serum liver enzyme levels, although they did not require treatment discontinuation, whereas 2.0% or 9.3% of fluconazole and echinocandin users had elevated serum liver enzyme levels but did not require treatment discontinuation. The results were similar when we stratified the data by empirical or definitive antifungal therapy. Possible explanations for antifungal agent-related hepatotoxicity were confounded by antifungal prescription to patients with a high risk of liver injury, the increased chance of detection of hepatotoxicity due to prolonged treatment, or the pharmacological entity.

Safety and efficacy of activated transfected killer cells for neutropenic fungal infections

BACKGROUND

Invasive fungal infections cause considerable morbidity and mortality in neutropenic patients. White blood cell transfusions are a promising treatment for such infections, but technical barriers have prevented their widespread use.

METHODS

To recapitulate white blood cell transfusions, we are developing a cell-based immunotherapy using a phagocytic cell line, HL-60. We sought to stably transfect HL-60 cells with a suicide trap (herpes simplex virus thymidine kinase), to enable purging of the cells when desired, and a bioluminescence marker, to track the cells in vivo in mice.

RESULTS

Transfection was stable despite 20 months of continuous culture or storage in liquid nitrogen. Activation of these transfected cells with retinoic acid and dimethyl sulfamethoxazole enhanced their microbicidal effects. Activated transfected killer (ATAK) cells were completely eliminated after exposure to ganciclovir, confirming function of the suicide trap. ATAK cells improved the survival of neutropenic mice with lethal disseminated candidiasis and inhalational aspergillosis. Bioluminescence and histopathologic analysis confirmed that the cells were purged from surviving mice after ganciclovir treatment. Comprehensive necropsy, histopathology, and metabolomic analysis revealed no toxicity of the cells.

CONCLUSIONS

These results lay the groundwork for continued translational development of this promising, novel technology for the treatment of refractory infections in neutropenic hosts.

Current therapeutic approaches to fungal infections in immunocompromised hematological patients

Invasive fungal infections are significant causes of morbidity and mortality in patients with hematological malignancies. Patients with acute myeloid leukemia and those who have undergone allogeneic hematopoietic stem cell transplantation are at especially high risk. Various fungal agents are responsible for this complication, but Aspergillus spp. and Candida spp. are the most frequently isolated micro-organisms; less commonly, infections could be caused by Zygomycetes or other rare molds or yeasts. Several new systemically-administered antifungal agents have been approved for clinical use since 2001; these agents include liposomal amphotericin B, voriconazole, caspofungin, and posaconazole, and they represent a major advance in antifungal therapy and have improved the prognosis of patients with hematological malignancies. This review focuses on therapeutic aspects of the management of fungal infections in hematological patients.

Clinical practice guidelines for the management of candidiasis: 2009 update by the Infectious Diseases Society of America

Guidelines for the management of patients with invasive candidiasis and mucosal candidiasis were prepared by an Expert Panel of the Infectious Diseases Society of America. These updated guidelines replace the previous guidelines published in the 15 January 2004 issue of Clinical Infectious Diseases and are intended for use by health care providers who care for patients who either have or are at risk of these infections. Since 2004, several new antifungal agents have become available, and several new studies have been published relating to the treatment of candidemia, other forms of invasive candidiasis, and mucosal disease, including oropharyngeal and esophageal candidiasis. There are also recent prospective data on the prevention of invasive candidiasis in high-risk neonates and adults and on the empiric treatment of suspected invasive candidiasis in adults. This new information is incorporated into this revised document.

Empirical antifungal therapy for patients with neutropenia and persistent fever: Systematic review and meta-analysis

OBJECTIVES

To assess the evidence for the current standard of practice of using empirical antifungal treatment in febrile neutropenic cancer patients.

METHODS

Systematic review and meta-analysis of randomised controlled trials comparing empirical or preemptive antifungal treatment with placebo, no intervention, or another antifungal. The primary outcomes were all-cause mortality and invasive fungal infections (IFI) (documented or probable). Relative risks (RR) with 95% confidence intervals (CI) were pooled.

RESULTS

Six trials assessed the efficacy of empirical treatment compared to no treatment and one compared empirical to preemptive therapy. Empirical treatment did not decrease mortality significantly (RR 0.82, 95% CI 0.50-1.34), but significantly decreased IFIs (RR 0.25, 0.12-0.54). Twenty-three trials assessed the efficiency of different antifungals. All-cause mortality was lower with azoles compared to amphotericin B (AB) (RR 0.81, 0.65-1.01); IFI rates were not different while adverse events were less frequent with azoles (RR 0.40; 0.34-0.66). Liposomal AB was associated with lower mortality and IFIs than other AB formulations (RR 1.57, 1.10-2.23 and 1.48, 0.98-2.25, respectively). Caspofungin was associated with fewer adverse events, but otherwise comparable to liposomal AB. All trials included patients with haematological malignancies. Major limitations included per-protocol analysis, non-blinded design and inconsistent definitions of IFIs.

CONCLUSIONS

Empirical antifungal treatment is associated with a lower rate of IFIs but no significant difference in overall mortality. The assessment of IFIs in these trials may have been biased, offering only weak support to standard practice. Azoles, liposomal amphotericin B or caspofungin should be preferred. Pre-emptive antifungal therapy should be considered and further investigated.

Current and future therapeutic options in the management of invasive aspergillosis

The past decade has witnessed significant progress in the management of invasive aspergillosis. Potent, relatively non-toxic antifungal drugs, data on early chest CT scanning and the availability of a non-invasive diagnostic test (serum galactomannan) are the key advances; among these, the contribution of the recently available drugs is the most significant. Safer and earlier intervention resulting in reduced mortality and improved outcome is being demonstrated. Newer strategies enable clinicians to provide drug therapy in a highly targeted manner, such that empirical use of antifungal drugs may decline. Voriconazole has become the drug of choice for primary therapy, while posaconazole shows promise as a prophylactic drug. Echinocandins are effective for salvage therapy and are under evaluation for primary therapy. Preliminary data for efficacy of combination therapy with a mould-active azole plus an echinocandin are of promise and clinical trials are under way. Reports of emergence of less-susceptible Aspergillus spp. during azole therapy are of concern and close monitoring is needed. Remarkably, the era of polyenes appears to be nearing the end in the therapy of invasive aspergillosis. The promise of newer classes of drugs, immune-modulating therapies and vaccines are exciting future additions to the arsenal against invasive aspergillosis.

Considerations in the approach to invasive fungal infection in patients with haematological malignancies

Invasive infections because of opportunistic yeasts and moulds have contributed significantly to the morbidity and mortality associated with potentially curative treatment for haematological malignancies. Many risk factors have been identified that permit the clinician to predict the likelihood of these infections. The diagnostic process involves maintaining a high index of suspicion based upon an understanding of the clinical circumstances under which invasive fungal infections occur, of the spectrum of fungal syndromes, and of the advantages and limitations of diagnostic testing strategies now available. Treatment strategies may be categorized as prophylactic, pre-emptive, empiric, or directed based upon the circumstances. The therapeutic options have increased in recent years but are not applicable to all clinical circumstances. These considerations are discussed.

Institutional Experience with Voriconazole Compared with Liposomal Amphotericin B as Empiric Therapy for Febrile Neutropenia

STUDY OBJECTIVE

To assess the effectiveness, safety, and cost of empiric treatment of febrile neutropenia before and after implementing an algorithm in which voriconazole was substituted for liposomal amphotericin B (L-AmB).

DESIGN

Retrospective cohort analysis.

SETTING

An 850-bed tertiary care hospital, which is also a referral site for patients with acute leukemia.

PATIENTS

Fifty-five adult patients who started empiric antifungal therapy for febrile neutropenia between January 1, 2002, and December 31, 2003, encompassing 58 treatment episodes (defined as a hospitalization during which empiric antifungal therapy was administered).

MEASUREMENTS AND MAIN RESULTS

Medical charts, including patients' pharmacy and laboratory data, were reviewed. Twenty-six and 32 episodes of L-AmB and voriconazole use, respectively, were identified. No significant differences between the L-AmB and voriconazole groups were noted at baseline. Rates of fever resolution (54% vs 59%, p=0.791) and breakthrough invasive fungal infections (11% vs 12%, p>0.999) were similar for the L-AmB and voriconazole episodes. Premature drug discontinuation due to the prescriber's perceived lack of efficacy occurred most frequently in the voriconazole group (25% vs 8%, p=0.160). Survival was significantly higher in the voriconazole than in the L-AmB group (100% vs 77%, p=0.006). Adverse effects that were significantly more common in the L-AmB group than in the voriconazole group were elevated serum creatinine levels (27% vs 3%, p=0.017) and electrolyte disturbances (19% vs 0%, p=0.014). Adverse effects reported more frequently in the voriconazole group than in the L-AmB group were visual disturbances (9% vs 0%, p=0.245) and elevated hepatic enzyme levels (9% vs 8%, p>0.999). Mean drug expenditures/episode for initial empiric antifungal therapy were lower for voriconazole than for L-AmB ($1593 vs $4144, or $153 vs $380/day).

CONCLUSION

Our institution's algorithm incorporating voriconazole into the empiric management of febrile neutropenia was associated with effectiveness outcomes comparable to those observed with L-AmB as well as a lower frequency of adverse effects and overall expenditures for antifungal drugs.

Antifungal therapy in children with invasive fungal infections: a systematic review

Invasive fungal infections are associated with significant morbidity and mortality. Differences between children and adults are reported, yet few trials of antifungal agents have been performed in pediatric populations. We performed a systematic review of the literature to guide appropriate pediatric treatment recommendations. From available trials that compared antifungal agents in either prolonged febrile neutropenia or invasive candidal or Aspergillus infection, no clear difference in treatment efficacy was demonstrated, although few trials were adequately powered. Differing antifungal pharmacokinetics between children and adults were demonstrated, requiring dose modification. Significant differences in toxicity, particularly nephrotoxicity, were identified between classes of antifungal agents. Therapy needs to be guided by the pathogen or suspected pathogens, the degree of immunosuppression, comorbidities (particularly renal dysfunction), concurrent nephrotoxins, and the expected length of therapy.

Interventions for preventing oral candidiasis for patients with cancer receiving treatment

BACKGROUND

Treatment of cancer is increasingly more effective but is associated with short and long term side effects. Oral side effects remain a major source of illness despite the use of a variety of agents to prevent and treat them. One of these side effects is oral candidiasis.

OBJECTIVES

To assess the effectiveness of interventions (which may include placebo or no treatment) for the prevention of oral candidiasis for patients with cancer receiving chemotherapy or radiotherapy or both.

SEARCH STRATEGY

Computerised searches of Cochrane Oral Health Group and PAPAS Trials Registers, CENTRAL, MEDLINE, EMBASE, CINAHL, CANCERLIT, SIGLE and LILACS were undertaken. Reference lists from relevant articles were searched and the authors of eligible trials were contacted to identify trials and obtain additional information. Date of the most recent searches: June 2006: CENTRAL (The Cochrane Library 2006, Issue 2).

SELECTION CRITERIA

Trials were selected if they met the following criteria: design - random allocation of participants; participants - anyone receiving chemotherapy or radiotherapy treatment for cancer; interventions - agents prescribed to prevent oral candidiasis; primary outcome - prevention of oral candidiasis.

DATA COLLECTION AND ANALYSIS

Data were recorded on the following secondary outcomes if present: relief of pain, amount of analgesia, relief of dysphagia, incidence of systemic infection, duration of stay in hospital (days), cost of oral care, patient quality of life, death, use of empirical antifungal treatment, toxicity and compliance. Information regarding methods, participants, interventions, outcome measures and results were independently extracted, in duplicate, by two review authors. The Cochrane Oral Health Group statistical guidelines were followed and risk ratios (RR) calculated using random-effects models. Potential sources of heterogeneity were examined in random-effects metaregression analyses.

MAIN RESULTS

Twenty-eight trials involving 4226 patients satisfied the inclusion criteria. Drugs absorbed and partially absorbed from the gastrointestinal (GI) tract were found to prevent oral candidiasis when compared to a placebo, or a no treatment control group, with RR for absorbed drugs = 0.47 (95% confidence interval (CI) 0.29 to 0.78). For absorbed drugs in populations with an incidence of 20% (mid range of results in control groups), this implies a NNT of 9 (95% CI 7 to 13) patients need to be treated to avoid one patient getting oral candidiasis. There was no significant benefit shown for drugs not absorbed from the GI tract.

AUTHORS' CONCLUSIONS

There is strong evidence, from randomised controlled trials, that drugs absorbed or partially absorbed from the GI tract prevent oral candidiasis in patients receiving treatment for cancer. There is also evidence that these drugs are significantly better at preventing oral candidiasis than drugs not absorbed from the GI.

Fluconazole for empiric antifungal therapy in cancer patients with fever and neutropenia

Background

Several clinical trials have demonstrated the efficacy of fluconazole as empiric antifungal therapy in cancer patients with fever and neutropenia. Our objective was to assess the frequency and resource utilization associated with treatment failure in cancer patients given empiric fluconazole antifungal therapy in routine inpatient care.

Methods

We performed a retrospective cohort study of cancer patients treated with oral or intravenous fluconazole between 7/97 and 6/01 in a tertiary care hospital. The final study cohort included cancer patients with neutropenia (an absolute neutrophil count below 500 cells/mm³) and fever (a temperature above 38°C or 100.4°F), who were receiving at least 96 hours of parenteral antibacterial therapy prior to initiating fluconazole. Patients' responses to empiric therapy were assessed by reviewing patient charts.

Results

Among 103 cancer admissions with fever and neutropenia, treatment failure after initiating empiric fluconazole antifungal therapy occurred in 41% (95% confidence interval (CI) 31% – 50%) of admissions. Patients with a diagnosis of hematological malignancy had increased risk of treatment failure (OR = 4.6, 95% CI 1.5 – 14.8). When treatment failure occurred the mean adjusted increases in length of stay and total costs were 7.4 days (95% CI 3.3 – 11.5) and $18,925 (95% CI 3,289 – 34,563), respectively.

Conclusion

Treatment failure occurred in more than one-third of neutropenic cancer patients on fluconazole as empiric antifungal treatment for fever in routine clinical treatment. The increase in costs when treatment failure occurs is substantial.

The debate: The trials have told us very little

The original trials of empiric intravenous amphotericin-B in the 1980s failed to prove conclusively its efficacy in the treatment of febrile neutropenia. Despite that, all subsequent studies of the therapy of presumed, possible, probable and proven invasive aspergillosis have assumed that this drug, either as deoxycholate or in lipid-based form, is the gold standard treatment against which all newcomers should be compared. This has led to a series of further inconclusive randomized controlled trials of empiric therapy as a result of which the most we can say is that nearly all new drugs are less toxic but also no more effective than amphotericin-B deoxycholate. The toxicity of the non-lipid formulation of this drug should have led us to withdraw it from both RCTs and routine clinical practice some years ago in view of the increasing evidence of equivalent efficacy and lower toxicity of other agents including lipid amphotericin formulations.Recent studies of the use of newer diagnostic techniques (i.e., CT and serology) reinforce the need to abandon the empiric trial approach in which we have repeatedly shown lack of superiority in the treatment of an infection which most patients do not have. Even in the small number of trials of the therapy of proven or probable invasive aspergillosis, results have been inconclusive or at best confusing in trying to find a better option than amphotericin-B. The trial of voriconazole versus amphotericin-B deoxycholate for this indication is a model for study for all those interested in the difficulties of designing trials which lead to convincing results.Effective prophylaxis trials and their analyses began by following a more rational pathway, first showing convincingly that fluconazole reduced the risk of C. albicans systemic infection in transplant patients. Unfortunately the widespread faith in the ability of this drug to prevent a wider range of systemic fungal infections in a wider range of patients is simply not supported by the data from many subsequent single trials and meta-analyses. This attachment to fluconazole has been mirrored by unwillingness to accept the evidence that itraconazole is superior in prophylaxis to fluconazole which is inactive against Aspergillus spp. In this case the trials have not told us enough because we have not believed the results. Results of trials of extended range azoles such as posaconazole are interesting but there are insufficient data to claim that posaconazole is superior to itraconazole.The progress in therapy and prophylaxis of systemic fungal infection has been unsatisfactory and slow. A new approach is needed for the design of clinical trials for these indications. There is good evidence that supportive investigations should now be used routinely in clinical practice and trials to increase certainty about the presence of invasive infection, to limit unnecessary use of expensive and toxic drugs and to improve analysis of efficacy of old and new antifungal agents.

New strategies of antifungal therapy in hematopoietic stem cell transplant recipients and patients with hematological malignancies

Invasive fungal infections (IFIs) are associated with considerable morbidity and mortality among high-risk individuals. Outcomes for IFI historically have been suboptimal and associated with a high mortality rate, hence global prophylaxis strategies have been applied to at-risk populations. Among certain populations, fluconazole prophylaxis has reduced systemic and superficial infections caused by Candida species. Newer azoles are currently being evaluated as prophylaxis and have the potential to provide protection against mould pathogens that are more troublesome to treat once they occur. Global prophylaxis strategies have the shortcoming of subjecting patients to therapy that ultimately will not need it. Targeted prophylaxis has the advantage of treating only patients at highest risk using some parameter of greater host susceptibility. Prophylaxis strategies are most suitable in patients at the highest risk for IFI. For patient groups whose risk is somewhat lower or when suspicion of IFI occurs in patients receiving prophylaxis, empirical antifungal therapy is often employed following a predefined period of fever. Again this approach subjects many non-infected patients to unnecessary and toxic therapy. A more refined approach such as presumptive or pre-emptive therapy whereby treatment is only initiated upon positive identification of a surrogate marker of infection in combination with clinical and radiological signs will subject fewer patients to toxic and expensive treatments.

Fungal infection-related mortality versus total mortality as an outcome in trials of antifungal agents

BACKGROUND

Disease specific mortality is often used as outcome rather than total mortality in clinical trials. This approach assumes that the classification of cause of death is unbiased. We explored whether use of fungal infection-related mortality as outcome rather than total mortality leads to bias in trials of antifungal agents in cancer patients.

METHODS

As an estimate of bias we used relative risk of death in those patients the authors considered had not died from fungal infection. Our sample consisted of 69 trials included in four systematic reviews of prophylactic or empirical antifungal treatment in patients with cancer and neutropenia we have published previously.

RESULTS

Thirty trials met the inclusion criteria. The trials comprised 6130 patients and 869 deaths, 220 (25%) of which were ascribed to fungal infection. The relative risk of death was 0.85 (95% CI 0.75-0.96) for total mortality, 0.57 (95% CI 0.44-0.74) for fungal mortality, and 0.95 (95% CI 0.82-1.09) for mortality among those who did not die from fungal infection.

CONCLUSION

We could not support the hypothesis that use of disease specific mortality introduces bias in antifungal trials on cancer patients as our estimate of the relative risk for mortality in those who survived the fungal infection was not increased. We conclude that it seems to be reliable to use fungal mortality as the primary outcome in trials of antifungal agents. Data on total mortality should be reported as well, however, to guard against the possible introduction of harmful treatments.

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.

Cost-effectiveness analysis of antifungal treatment for patients on chemotherapy

Invasive fungal infections are fatal complications for patients on chemotherapy, and antifungal prophylactic treatment has been commonly recommended. Because its clinical and economic impact is not well known, we evaluated cost-effectiveness of anti-fungal treatment for patients who were neutropoenic as a result of chemotherapy. We constructed a hypothetical cohort of 40-year-old patients with acute myelogenic leukemia to evaluate years of life survived (YLS), costs (US$), and incremental cost-effectiveness ratio (US$/YLS). The following treatment strategies for fungal infections were compared: (1) prophylactic fluconazole strategy: oral fluconazole administration concurrently with chemotherapy; (2) empirical amphotericin B strategy: empirical intravenous amphotericin B administration at the point where fever is detected; and (3) no prophylaxis strategy: intravenous micafangin administration at the point where fungal infections is diagnosed. Baseline analyses showed that prophylactic fluconazole strategy involved higher costs but also longer YLSs (25,900 US$ and 24.08 YLS). The incremental cost-effectiveness ratio of prophylactic fluconazole strategy was 625 US$/YLS compared to no prophylaxis strategy, and 652 US$/YLS compared to empirical amphotericin B strategy. Baseline result was found to be robust through sensitivity analyses. Our study showed that concurrent administration of oral fluconazole during induction chemotherapy appears to ensure clinical benefits together with acceptable cost-effectiveness.

Empirical antifungal therapy in patients with neutropenia and persistent or recurrent fever of unknown origin

Persistent or recurrent fever of unexplained origin (PFUO) in neutropenic patients receiving antibiotic therapy is commonly treated with empirical antifungal therapy (EAFT). EAFT was established as an adequate management of PFUO around 20 years ago with conventional amphotericin B deoxycholate (c-AmB), despite its high rate of infusional and systemic toxicities. In recent years, EAFT trials for PFUO have used less toxic agents, such as the lipid formulations of AmB, the new azoles, and the echinocandin, caspofungin. In clinical trials, the lipid formulations of AmB [especially liposomal AmB (L-AmB)] provided similar efficacy with lower toxicity but at a much higher cost. Although rarely used in clinical practice, fluconazole is equivalent to c-AmB, provided patients at high risk of Aspergillus infections are excluded. Intravenous itraconazole was shown to be equivalent to c-AmB, with a lower toxicity. Voriconazole did not meet non-inferiority criteria when compared with L-AmB. Caspofungin was shown to be non-inferior to L-AmB and more effective in treating baseline invasive fungal infections. To date, alternatives to AmB have shown less toxicity, but improved efficacy is less clear. This is probably because of the weakness of the indication and to the consequent difficulty in establishing objective and reproducible endpoints for comparisons. The new challenge for physicians in this field is probably presumptive antifungal therapy, an approach based on patient risk-group stratification for developing invasive candidiasis or aspergillosis and/or the use of new diagnostic techniques to identify patients at a very early stage of infection.

Micafungin, a novel antifungal agent, as empirical therapy in acute leukemia patients with febrile neutropenia

OBJECTIVE

Invasive fungal infection is a major cause of morbidity and mortality in patients with febrile neutropenia unresponsive to antibacterial treatment. Empirical antifungal therapy with amphotericin B has been the standard of care for these patients; however, there remains a need for less toxic alternative drugs.

PATIENTS AND METHODS

We conducted a prospective study to evaluate the efficacy and safety of micafungin (MCFG), a novel antifungal agent of the echinocandin class, in an empirical therapy setting for patients with febrile neutropenia.

RESULTS

A total of 31 patients with acute leukemia who developed febrile neutropenia were enrolled in the study. Among them, 18 patients fulfilling the protocol-defined criteria, including 10 with persistent fever and 8 with recurrent fever, received MCFG empirically. Underlying diseases consisted of acute myeloid leukemia (n=15) and acute lymphoblastic leukemia (n=3). The median duration of neutropenia and drug administration was 22 and 9.5 days, respectively. Treatment success, defined as defervescence during the neutropenic period, absence of breakthrough fungal infections, and requiring no replacement of antifungal drugs, was achieved in 14 patients (78%). None of the patients required discontinuation or dose reduction due to adverse events except for one patient with severe hypokalemia.

CONCLUSIONS

Although the studied patients were limited in number, our results indicate that MCFG is an encouraging agent for empirical antifungal therapy in patients with febrile neutropenia, and deserves further investigation in large-scale studies.

The hepatotoxicity of antifungal medications in bone marrow transplant recipients

BACKGROUND

Systemic antifungal medications can be lifesaving but can also have important toxicities. With a number of new antifungal drugs being introduced, there is a compelling need to define the toxicities associated with existing therapies.

METHODS

We identified cases of hepatotoxicity among patients who underwent bone marrow transplantation and selected matched control subjects from the same population. Multivariable logistic regression modeling was used to control for patient characteristics in evaluating the relationship between hepatotoxicity and exposure to antifungal medications. Follow-up analyses were performed for patients who continued receiving antifungal medications after developing hepatotoxicity.

RESULTS

The unadjusted incidence of hepatotoxicity was 0.78 cases per 100 patient-days of exposure to amphotericin deoxycholate, 0.98 for fluconazole, and 1.50 for liposomal amphotericin B. Case-control analyses found that liposomal amphotericin B was associated with a substantial increase in the risk of hepatotoxicity in these patients (odds ratio [OR], 3.33; 95% confidence interval [CI], 1.61-6.88); a smaller increase in risk was found for fluconazole (OR, 1.99; 95% CI, 1.21-3.26). There was no statistically significant association between amphotericin B deoxycholate and the development of hepatotoxicity. Patients had greater elevations of serum transaminase values associated with exposure to larger cumulative doses of liposomal amphotericin B. In the follow-up analysis of patients who developed hepatotoxicity and who continued receiving antifungal medication, one-third of those receiving liposomal amphotericin B had marked increases in bilirubin levels, as opposed to 8% of patients treated with fluconazole.

CONCLUSIONS

In these bone marrow transplant recipients, liposomal amphotericin B and fluconazole were both associated with increased risk of hepatotoxicity, independent of other treatments received or patient characteristics; the magnitude of the risk was larger for liposomal amphotericin B. Patients who develop hepatotoxicity appear to tolerate continued therapy with fluconazole, but a large fraction of those who received liposomal amphotericin B have worsening conditions with continued treatment.

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.

Interventions for preventing oral candidiasis for patients with cancer receiving treatment

BACKGROUND

Treatment of cancer is increasingly more effective but is associated with short and long term side effects. Oral side effects remain a major source of illness despite the use of a variety of agents to prevent and treat them. One of these side effects is oral candidiasis.

OBJECTIVES

To assess the effectiveness of interventions (which may include placebo or no treatment) for the prevention of oral candidiasis for patients with cancer receiving chemotherapy and/or radiotherapy.

SEARCH STRATEGY

Electronic databases: Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE, MEDLINE Pre-indexed, EMBASE, CINAHL, CANCERLIT, SIGLE and LILACS were searched. Date of the most recent searches April 2004 (CENTRAL Issue 2, 2004).

SELECTION CRITERIA

Trials were selected if they met the following criteria: design - random allocation of participants; participants - anyone receiving chemotherapy or radiotherapy treatment for cancer; interventions - agents prescribed to prevent oral candidiasis; primary outcome - prevention of oral candidiasis.

DATA COLLECTION AND ANALYSIS

Data were recorded on the following secondary outcomes if present: relief of pain, amount of analgesia, relief of dysphagia, incidence of systemic infection, duration of stay in hospital (days), cost of oral care, patient quality of life, death, use of empirical antifungal treatment, toxicity and compliance. Information regarding methods, participants, interventions, outcome measures and results were independently extracted, in duplicate, by two reviewers (HW & JC). The Cochrane Oral Health Group statistical guidelines were followed and relative risk values calculated using random effects models. Potential sources of heterogeneity were examined in random effects metaregression analyses.

MAIN RESULTS

Twenty-eight trials involving 4226 patients satisfied the inclusion criteria. Drugs absorbed and partially absorbed from the gastrointestinal (GI) tract were found to prevent oral candidiasis when compared to a placebo, or a no treatment control group, with RR for absorbed drugs = 0.47 (95% CI 0.29 to 0.78). For absorbed drugs in populations with an incidence of 20% (mid range of results in control groups), this implies a NNT of 9 (95% CI 7 to 13) patients need to be treated to avoid one patient getting oral candidiasis. There was no significant benefit shown for drugs not absorbed from the GI tract.

REVIEWERS' CONCLUSIONS

There is strong evidence, from randomised controlled trials, that drugs absorbed or partially absorbed from the GI tract prevent oral candidiasis in patients receiving treatment for cancer. There is also evidence that these drugs are significantly better at preventing oral candidiasis than drugs not absorbed from the GI.

Oral Fluconazole for Empiric Treatment of Prolonged Fever in Neutropenic Patients

Neutropenic patients who continue to be febrile despite adequate broad-spectrum antibacterial treatment require empirical antifungal therapy. The aim of the present study was to evaluate the safety and efficacy of oral fluconazole for empirical antifungal therapy in neutropenic patients with persistent fever. A prospective cohort design was used. The study sample included 250 consecutive patients with high-risk stage II, III, or responding metastatic breast cancer who received high-dose chemotherapy (HDC) with autologous peripheral blood progenitor stem cell transplantation. Those with neutropenic fever lasting more than 72 hours despite broad-spectrum antibacterial coverage were treated with fluconazole. Treatment was continued until fever dropped and/or neutrophil count recovered with blood cultures remaining negative. Antifungal treatment was required in 173 patients (69%). There were no cases of documented deep systemic fungal infection. Two patients (<1%) had positive blood cultures for fungi. None of the patients experienced toxicity related to fluconazole. There was one transplant-related death. Thirty-one patients (18%) were unable to complete the oral fluconazole protocol because of severe mucositis, and they received intravenous fluconazole at the same dose, with similar efficacy. Oral fluconazole is a safe and effective alternative to amphotericin B for empirical early antifungal treatment in persistent neutropenic fever in breast cancer patients undergoing HDC with autologous stem cell support. Further study of oral fluconazole and amphotericin B as empirical agents in other groups of patients with persistent neutropenic fever is warranted.

Combined Assessment of β-d-Glucan and Degree of Candida Colonization before Starting Empiric Therapy for Candidiasis in Surgical Patients

The purpose of the study was to investigate whether examination for plasma beta-D-glucan, a cell wall constituent of fungi, is useful for selecting surgical patients with Candida colonization who would benefit from empiric antifungal therapy. We administered fluconazole to postoperative patients with Candida colonization who have risk factors for candidemia and complained of persistent fever despite prolonged antibacterial therapy. We then analyzed the clinical outcomes regarding the number of sites colonized with Candida spp. and plasma beta-D-glucan. Of the 32 patients positive for alpha-D-glucan, 15 (46.9%) responded to the empiric therapy; only 9% of those who were negative responded (p < 0.01). In the multiple logistic regression analysis, being positive for alpha-D-glucan was a significant factor predicting response, with an adjusted odds ratio of 12.9 in patients with Candida colonization [95% confidence interval (CI) 2.07-80.73) (p < 0.01). In addition, the number of sites colonized with Candida spp. was a significant factor predicting response, with an estimated exposure odds ratio of 7.57 for those who were colonized at three or more sites compared with those colonized at one site (95% CI 1.20-47.70) (p = 0.031). In patients with Candida colonization, assessment of beta-D-glucan was useful for deciding whether to start empiric therapy for suspected candidiasis in surgical patients.

Empirical antifungal therapy

The number of fungal infections is increasing, particularly in patients with cancer, and represent a major problem given the relatively poor response rates, especially for aspergillosis, and the high cost. Empirical therapy has become an accepted practice as delay in instituting therapy is clearly associated with increased morbidity and mortality. In terms of efficacy for the management of persistent febrile neutropenic patients, there is no convincing evidence that conventional amphotericin B (ampho B) is inferior to any other agent; the lipid formulations of ampho B provide similar efficacy with lower toxicity but at a much higher cost. Fluconazole is equivalent to ampho B, provided patients at high risk of aspergillus infections are excluded. Itraconazole and voriconazole, as empirical therapies, are equivalent to conventional ampho B and liposomal ampho B, respectively; toxicity is definitely lower and voriconazole is more effective at preventing breakthrough fungal infections.

Guidelines for the use of antifungal agents in the treatment of invasiveCandidaand mould infections

ABSTRACT Treatment of invasive fungal infections is increasingly complex. Amphotericin B deoxycholate has long been the mainstay of treatment. However, there has been increasing recognition of both the propensity for nephro-toxicity in haematology, transplant and intensive care patients as well as its adverse impact on morbidity and mortality. This has coincided with the availabilty of newer, and in certain settings, more effective antifungal agents. Although the newer agents clearly cause less nephrotoxicity than amphotericin B, drug interactions, hepatic effects and unique side-effects need to be considered. The spectrum of the newer triazoles and echinocandins varies, highlighting the importance of accurate identification of the causative organism where possible. Consensus Australian guidelines have been developed to assist clinicians with treatment choices by reviewing the current evidence for the efficacy, the toxicity and the cost of these agents.

Metaanálisis de la seguridad y eficacia de la anfotericina B liposómica en el tratamiento empírico de la neutropenia febril

BACKGROUND AND OBJECTIVE

We compared the safety and efficacy of liposomal amphotericin B with other formulations of amphotericin B and voriconazol as an empirical treatment of febrile neutropenia.

MATERIAL AND METHOD

Several randomized controlled clinical trials, designed to evaluate the safety and/or efficacy of liposomal amphotericin B in the empirical treatment of febrile neutropenia, in comparison with other amphotericin B formulations or voriconazol, were identified by means of a search in MEDLINE, EMBASE and Cochrane Controlled Trials Register's data bases. American Society of Microbiology and American Society of Clinical Oncology abstracts, presented between 1999 and 2002, were also included in the search. Prior to data extraction, concepts like nephrotoxicity, infusion-related adverse events and efficacy (success rate and mortality) were defined.

RESULTS

Two studies comparing liposomal amphotericin B with conventional amphotericin B, one comparing liposomal amphotericin B with amphotericin B lipid complex and one comparing liposomal amphotericin B with voriconazol were included in the analysis. Patients treated with liposomal amphotericin B had lower nephrotoxicity than patients treated with other amphotericin B formulations or with conventional amphotericin B (RR = 0.49); conversely, no statistically significant differences with regard to voriconazol were observed. In terms of efficacy, mortality rate and therapeutic failure, patients treated with limposomal amphotericin B showed a slightly higher efficacy.

CONCLUSIONS

Liposomal amphotericin B is a lipidic formulation with a slightly higher efficacy than other amphotericin B formulations and voriconazol. In terms of nephrotoxicity, liposomal amphotericin B showed lower nephrotoxicity than other amphotericines while its safety rates were similar to those of voriconazol.

In Vitro Susceptibility of Candida Species Isolated from Cancer Patients to Some Antifungal Agents

This study was undertaken to study the resistance of Candida species isolated from oropharyngeal swabs of cancer patients to ketoconazole (KET), fluconazole (FLU), amphotericin B (AmpB), and flucytosine (FCU). The most common species identified was C. albicans, followed by C. tropicalis, C. glabrata, C. famata, C. krusei, C. kefyr, and C. gulliermondii. The minimum inhibitory concentration (MIC) of the antifungal agents was evaluated by RPMI 1640 medium with microdilution method. There were no C. albicans strains resistant to KET, FLU and AmpB. All Candida isolates were found highly susceptible to AmpB (MIC AmpB < 1 microg/ml), followed by KET (MIC KET < or =8 microg/ml), FLU (MIC FLU < or =8 microg/ml) and FCU (MIC FCU < or =4 microg/ml). The main conclusion of this study is that prophylactic therapy planned according to typing and antifungal susceptibility will contribute to the prevention of invasive fungal infections in immunosuppressied oncology patients.

Voriconazole for serious fungal infections

Voriconazole is a new second generation triazole effective against a wide spectrum of fungal pathogens. A randomised, controlled trial has shown it to be superior to amphotericin B in invasive aspergillosis, and it is a potential alternative to amphotericin B in neutropenic sepsis and to fluconazole in oesophageal candidiasis. Early clinical reports and in vitro susceptibility data suggest that it may also be a valuable antifungal against fluconazole-resistant Candida species and certain emerging fungal pathogens, which cause infections that are often refractory to conventional therapies. There is limited evidence of azole cross-resistance of clinical importance. Voriconazole is available as intravenous and oral formulations and has excellent tissue penetration and a good safety profile, the main problems being transient visual impairment and hepatotoxicity in patients with liver disease. It is metabolised by cytochrome P-450 isoenzymes causing important drug interactions but, in contrast to amphotericin B, is safe in renal failure and rarely causes infusion-related reactions. This review outlines the pharmacology of voriconazole and focuses on its clinical applications and safety profile.