Amphotericin B lipid soluble formulations vs amphotericin B in cancer patients with neutropenia

Consensus guidelines for optimising antifungal drug delivery and monitoring to avoid toxicity and improve outcomes in patients with haematological malignancy and haemopoietic stem cell transplant recipients, 2021

Antifungal agents can have complex dosing and the potential for drug interaction, both of which can lead to subtherapeutic antifungal drug concentrations and poorer clinical outcomes for patients with haematological malignancy and haemopoietic stem cell transplant recipients. Antifungal agents can also be associated with significant toxicities when drug concentrations are too high. Suboptimal dosing can be minimised by clinical assessment, laboratory monitoring, avoidance of interacting drugs, and dose modification. Therapeutic drug monitoring (TDM) plays an increasingly important role in antifungal therapy, particularly for antifungal agents that have an established exposure-response relationship with either a narrow therapeutic window, large dose-exposure variability, cytochrome P450 gene polymorphism affecting drug metabolism, the presence of antifungal drug interactions or unexpected toxicity, and/or concerns for non-compliance or inadequate absorption of oral antifungals. These guidelines provide recommendations on antifungal drug monitoring and TDM-guided dosing adjustment for selected antifungal agents, and include suggested resources for identifying and analysing antifungal drug interactions. Recommended competencies for optimal interpretation of antifungal TDM and dose recommendations are also provided.

ESICM/ESCMID task force on practical management of invasive candidiasis in critically ill patients

INTRODUCTION

The term invasive candidiasis (IC) refers to both bloodstream and deep-seated invasive infections, such as peritonitis, caused by Candida species. Several guidelines on the management of candidemia and invasive infection due to Candida species have recently been published, but none of them focuses specifically on critically ill patients admitted to intensive care units (ICUs).

MATERIAL AND METHODS

In the absence of available scientific evidence, the resulting recommendations are based solely on epidemiological and clinical evidence in conjunction with expert opinion. The task force used the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach to evaluate the recommendations and assign levels of evidence. The recommendations and their strength were decided by consensus and, if necessary, by vote (modified Delphi process). Descriptive statistics were used to analyze the results of the Delphi process. Statements obtaining > 80% agreement were considered to have achieved consensus.

CONCLUSIONS

The heterogeneity of this patient population necessitated the creation of a mixed working group comprising experts in clinical microbiology, infectious diseases and intensive care medicine, all chosen on the basis of their expertise in the management of IC and/or research methodology. The working group's main goal was to provide clinicians with clear and practical recommendations to optimize microbiological diagnosis and treatment of IC. The Systemic Inflammation and Sepsis and Infection sections of the European Society of Intensive Care Medicine (ESICM) and the Critically Ill Patients Study Group of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) therefore decided to develop a set of recommendations for application in non-immunocompromised critically ill patients.

Consensus guidelines for optimising antifungal drug delivery and monitoring to avoid toxicity and improve outcomes in patients with haematological malignancy, 2014

Antifungal agents may be associated with significant toxicity or drug interactions leading to sub-therapeutic antifungal drug concentrations and poorer clinical outcomes for patients with haematological malignancy. These risks may be minimised by clinical assessment, laboratory monitoring, avoidance of particular drug combinations and dose modification. Specific measures, such as the optimal timing of oral drug administration in relation to meals, use of pre-hydration and electrolyte supplementation may also be required. Therapeutic drug monitoring (TDM) of antifungal agents is warranted, especially where non-compliance, non-linear pharmacokinetics, inadequate absorption, a narrow therapeutic window, suspected drug interaction or unexpected toxicity are encountered. Recommended indications for voriconazole and posaconazole TDM in the clinical management of haematology patients are provided. With emerging knowledge regarding the impact of pharmacogenomics upon metabolism of azole agents (particularly voriconazole), potential applications of pharmacogenomic evaluation to clinical practice are proposed.

The role of medications and their management in acute kidney injury

Prior to 2002, the incidence of acute renal failure (ARF) varied as there was no standard definition. To better understand its incidence and etiology and to develop treatment and prevention strategies, while moving research forward, the Acute Dialysis Quality Initiative workgroup developed the RIFLE (risk, injury, failure, loss, end-stage kidney disease) classification. After continued data suggesting that even small increases in serum creatinine lead to worse outcomes, the Acute Kidney Injury Network (AKIN) modified the RIFLE criteria and used the term acute kidney injury (AKI) instead of ARF. These classification and staging systems provide the clinician and researcher a starting point for refining the understanding and treatment of AKI. An important initial step in evaluating AKI is determining the likely location of injury, generally classified as prerenal, renal, or postrenal. There is no single biomarker or test that definitively defines the mechanism of the injury. Identifying the insult(s) requires a thorough assessment of the patient and their medical and medication histories. Prerenal injuries arise primarily due to renal hypoperfusion. This may be the result of systemic or focal conditions or secondary to the effects of drugs such as nonsteroidal anti-inflammatory drugs, calcineurin inhibitors (CIs), and modulators of the renin-angiotensin-aldosterone system. Renal, or intrinsic, injury is an overarching term that represents complex conditions leading to considerable damage to a component of the intrinsic renal system (renal tubules, glomerulus, vascular structures, inter-stitium, or renal tubule obstruction). Acute tubular necrosis and acute interstitial nephritis are the more common types of intrinsic renal injury. Each type of injury has several drugs that are implicated as a possible cause, with antiinfectives being the most common. Postrenal injuries that result from obstruction block the flow of urine, leading to hydronephrosis and subsequent damage to the renal parenchyma. Drugs associated with tubular obstruction include acyclovir, methotrexate, and several antiretrovirals. Renal recovery from drug-induced AKI begins once the offending agent has been removed, if clinically possible, and is complete in most cases. It is uncommon that renal replacement therapy will be needed while recovery occurs. Pharmacists can play a pivotal role in identifying possible causes of drug-induced AKI and limit their toxic effect by identifying those most likely to cause or contribute to injury. Dose adjustment is critical during changes in renal function, and the pharmacist can ensure that optimal therapy is provided during this critical time.

Amphotericin B lipid soluble formulations versus amphotericin B in cancer patients with neutropenia

BACKGROUND

Patients with cancer who are treated with chemotherapy or receive a bone marrow transplant have an increased risk of acquiring fungal infections. Such infections can be life-threatening. Antifungal drugs are therefore often given prophylactically to such patients, or when they have a fever.

OBJECTIVES

To compare the benefits and harms of lipid soluble formulations of amphotericin B with conventional amphotericin B in cancer patients with 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 lipid soluble formulations of amphotericin B with conventional amphotericin B.

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

We found 13 trials (1960 patients). Lipid-based amphotericin B was not more effective than conventional amphotericin B on mortality (relative risk (RR) 0.5; 95% confidence interval (CI) 0.64 to 1.14) but decreased invasive fungal infection (RR 0.65; 95% CI 0.44 to 0.97), nephrotoxicity defined as a 100% increase in serum creatinine (RR 0.45; 95% CI 0.37 to 0.54), and number of dropouts (RR 0.78; 95% CI 0.62 to 0.97).For the drug used in most patients, AmBisome (4 trials, 1214 patients), there was no significant difference in mortality (RR 0.77; 95% CI 0.54 to 1.10) whereas it tended to be more effective than conventional amphotericin B on invasive fungal infection (RR 0.63; 95% CI 0.39 to 1.01, P value 0.053).AmBisome, amphotericin B in Intralipid (6 trials, 379 patients), amphotericin B colloidal dispersion (ABCD) (2 trials, 262 patients), and amphotericin B lipid complex (ABLC) (1 trial, 105 patients) all decreased the occurrence of nephrotoxicity, but conventional amphotericin B was rarely administered under optimal circumstances.

AUTHORS' CONCLUSIONS

It is not clear whether there are any advantages of lipid-based formulations if conventional amphotericin B is administered under optimal circumstances, and their high cost prohibits routine use in most settings. There is a need for large trials comparing lipid-based formulations of amphotericin B with conventional amphotericin B given in the same dose, with routine premedication for prevention of infusion-related toxicity, and with supplementation with fluid, potassium, and magnesium for prevention of nephrotoxicity.

Routine versus selective antifungal administration for control of fungal infections in patients with cancer

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 assess whether commonly used antifungal drugs decrease mortality in cancer patients with neutropenia.

SEARCH METHODS

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

SELECTION CRITERIA

Randomised clinical trials of amphotericin B, fluconazole, ketoconazole, miconazole, itraconazole or voriconazole compared with placebo or no treatment in cancer patients with neutropenia.

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

Thirty-two trials involving 4287 patients were included. Prophylactic or empirical treatment with amphotericin B significantly decreased total mortality (relative risk (RR) 0.69, 95% confidence interval (CI) 0.50 to 0.96), whereas the estimated RRs for fluconazole, ketoconazole, miconazole, and itraconazole were close to 1.00. No eligible trials were found with voriconazole. Amphotericin B and fluconazole decreased mortality ascribed to fungal infection (RR 0.45, 95% CI 0.26 to 0.76 and RR 0.42, 95% CI 0.24 to 0.73, respectively). The incidence of invasive fungal infection decreased significantly with administration of amphotericin B (RR 0.41, 95% CI 0.24 to 0.73), fluconazole (RR 0.39, 95% CI 0.27 to 0.57) and itraconazole (RR 0.53, 95% CI 0.29 to 0.97), but not with ketoconazole or miconazole. Effect estimates were similar for those 13 trials that had adequate allocation concealment and were blinded. The reporting of harms was far too variable from trial to trial to allow a meaningful overview. For the 2011 and 2014 updates no additional trials were identified for inclusion.

AUTHORS' CONCLUSIONS

Intravenous amphotericin B was the only antifungal agent that reduced total mortality. It should therefore be preferred when prophylactic or empirical antifungal therapy is introduced in cancer patients with neutropenia.

Voriconazole versus amphotericin B or fluconazole in cancer patients with neutropenia

BACKGROUND

Opportunistic fungal infections are a major cause of morbidity and mortality in neutropenic cancer patients and antifungal therapy is used both empirically and therapeutically in these patients.

OBJECTIVES

To compare the benefits and harms of voriconazole with those of amphotericin B and fluconazole when used for prevention or treatment of invasive fungal infections in cancer patients with neutropenia.

SEARCH METHODS

Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2014, Issue 1 2014), MEDLINE (to January 2014). Letters, abstracts and unpublished trials were accepted. Contact was made with trial authors and industry.

SELECTION CRITERIA

Randomised clinical trials comparing voriconazole with amphotericin B or fluconazole.

DATA COLLECTION AND ANALYSIS

Data on mortality, invasive fungal infection, colonisation, use of additional (escape) antifungal therapy and adverse effects leading to discontinuation of therapy were extracted independently by two review authors.

MAIN RESULTS

Three trials were included. One trial compared voriconazole to liposomal amphotericin B as empirical treatment of fever of unknown origin (suspected fungal infection) in neutropenic cancer patients (849 patients, 58 deaths). The second trial compared voriconazole to amphotericin B deoxycholate in the treatment of confirmed and presumed invasive Aspergillus infections (391 patients, 98 deaths). The third trial compared fluconazole to voriconazole for prophylaxis of fungal infections in patients receiving allogeneic stem cell transplantation (600 patients, number of deaths not stated). In the first trial, voriconazole was significantly inferior to liposomal amphotericin B according to the trial authors' prespecified criteria. More patients died in the voriconazole group and a claimed significant reduction in the number of breakthrough fungal infections disappeared when patients arbitrarily excluded from the analysis by the trial authors were included. In the second trial, the deoxycholate preparation of amphotericin B was used without any indication of the use of premedication to counter side effects and replacement of electrolytes or use of salt water. This choice of comparator resulted in a marked difference in the duration of treatment on the trial drugs (77 days with voriconazole versus 10 days with amphotericin B) and precluded meaningful comparisons of the benefits and harms of the two drugs. The third trial failed to find a difference in fungal free survival or invasive fungal infections at 180 days when voriconazole was compared to fluconazole.

AUTHORS' CONCLUSIONS

Liposomal amphotericin B is significantly more effective than voriconazole for empirical therapy of fungal infections in neutropenic cancer patients and should be preferred. For treatment of aspergillosis, there are no trials that have compared voriconazole with amphotericin B given under optimal conditions. For prophylactic fungal treatment in patients receiving allogeneic stem cell transplantation, there was no difference between voriconazole and fluconazole regarding fungal free survival or invasive fungal infections.

Amphotericin B formulations: a comparative review of efficacy and toxicity

Because of the increasing prevalence and changing microbiological spectrum of invasive fungal infections, some form of amphotericin B still provides the most reliable and broad spectrum therapeutic alternative. However, the use of amphotericin B deoxycholate is accompanied by dose-limited toxicities, most importantly, infusion-related reactions and nephrotoxicity. In an attempt to improve the therapeutic index of amphotericin B, three lipid-associated formulations were developed, including amphotericin B lipid complex (ABLC), liposomal amphotericin B (L-AmB), and amphotericin B colloidal dispersion (ABCD). The lipid composition of all three of these preparations differs considerably and contributes to substantially different pharmacokinetic parameters. ABLC is the largest of the lipid preparations. Because of its size, it is taken up rapidly by macrophages and becomes sequestered in tissues of the mononuclear phagocyte system such as the liver and spleen. Consequently, compared with the conventional formulation, it has lower circulating amphotericin B serum concentrations, reflected in a marked increase in volume of distribution and clearance. Lung levels are considerably higher than those achieved with other lipid-associated preparations. The recommended therapeutic dose of ABLC is 5 mg/kg/day. Because of its small size and negative charge, L-AmB avoids substantial recognition and uptake by the mononuclear phagocyte system. Therefore, a single dose of L-AmB results in a much higher peak plasma level (Cmax) than conventional amphotericin B deoxycholate and a much larger area under the concentration-time curve. Tissue concentrations in patients receiving L-AmB tend to be highest in the liver and spleen and much lower in kidneys and lung. Recommended therapeutic dosages are 3-6 mg/kg/day. After intravenous infusion, ABCD complexes remain largely intact and are rapidly removed from the circulation by cells of the macrophage phagocyte system. On a milligram-to-milligram basis, the Cmax achieved is lower than that attained by conventional amphotericin B, although the larger doses of ABCD that are administered produce an absolute level that is similar to amphotericin B. ABCD exhibits dose-limiting, infusion-related toxicities; consequently, the administered dosages should not exceed 3-4 mg/kg/day. The few comparative clinical trials that have been completed with the lipid-associated formulations have not demonstrated important clinical differences among these agents and amphotericin B for efficacy, although there are significant safety benefits of the lipid products. Furthermore, only one published trial has ever compared one lipid product against another for any indication. The results of these trials are particularly difficult to interpret because of major heterogeneities in study design, disease definitions, drug dosages, differences in clinical and microbiological endpoints as well as specific outcomes examined. Nevertheless, it is possible to derive some general conclusions given the available data. The most commonly studied syndrome has been empiric therapy for febrile neutropenic patients, where the lipid-associated preparations did not appear to provide a survival benefit over conventional amphotericin B deoxycholate, but did offer a significant advantage for the prevention of various breakthrough invasive fungal infections. For treatment of documented invasive fungal infections that usually involved hematological malignancy patients, no individual randomized trial has demonstrated a mortality benefit due to therapy with one of the lipid formulations. Results from meta-analyses have been contradictory, with one demonstrating a mortality benefit from all-cause mortality and one that did not demonstrate a mortality benefit. In the only published study to examine HIV-infected patients with disseminated histoplasmosis, clinical success and mortality were significantly better with L-AmB compared with amphotericin B deoxycholate; there were no differences in microbiological outcomes between treatment groups. The lipid-associated preparations were not significantly better than amphotericin B deoxycholate for treatment of AIDS-associated acute cryptococcal meningitis for either clinical or microbiological outcomes that were studied. In all of the trials that specifically examined renal toxicity, the lipid-associated formulations were significantly less nephrotoxic than amphotericin B deoxycholate. Infusion-related reactions occurred less frequently with L-AmB when compared with amphotericin B deoxycholate; however, ABCD had equivalent or more frequent infusion-related reactions than conventional amphotericin B, and this resulted in the cessation of at least one clinical trial. At the present time, this particular lipid formulation is no longer commercially available. For the treatment of most invasive fungal infections, an amphotericin B lipid formulation provides a safer alternative than conventional amphotericin B, with at least equivalent efficacy. As the cost of therapy with these agents continues to decline, these drugs will likely maintain their important role in the antifungal drug armamentarium because of their efficacy and improved safety profile.

Diagnosis, evaluation, and management of acute kidney injury: a KDIGO summary (Part 1)

Acute kidney injury (AKI) is a common and serious problem affecting millions and causing death and disability for many. In 2012, Kidney Disease: Improving Global Outcomes completed the first ever, international, multidisciplinary, clinical practice guideline for AKI. The guideline is based on evidence review and appraisal, and covers AKI definition, risk assessment, evaluation, prevention, and treatment. In this review we summarize key aspects of the guideline including definition and staging of AKI, as well as evaluation and nondialytic management. Contrast-induced AKI and management of renal replacement therapy will be addressed in a separate review. Treatment recommendations are based on systematic reviews of relevant trials. Appraisal of the quality of the evidence and the strength of recommendations followed the Grading of Recommendations Assessment, Development and Evaluation approach. Limitations of the evidence are discussed and a detailed rationale for each recommendation is provided.

Role of diuretics and lipid formulations in the prevention of amphotericin B-induced nephrotoxicity

PURPOSE

To collect available clinical data to define the role of diuretics and lipid formulations in the prevention of amphotericin B (AmB)-induced nephrotoxicity (AIN) in human populations.

METHOD

A literature search was performed in the following databases: Scopus, Medline, Embase, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews.

RESULTS AND CONCLUSION

Co-administration of mannitol failed to show any clinically significant benefit in preventing AIN. Potassium-sparing diuretics, such as amiloride and spironolactone, have been shown to have beneficial effects as an alternative or adjunct to oral/parenteral potassium supplements in preventing hypokalemia due to AmB. Lipid-based formulations of AmB are clinically effective and safe in preventing AIN. However, due to their high cost and limited accessibility, these formulations are generally used as second-line antifungal therapy in cases of conventional AmB refractoriness and/or intolerance or pre-existing renal dysfunction. The potential effects of other nephroprotective agents, such as N-acetylcysteine, AIN merit further considerations and investigations.

Antifungal therapy for newborn infants with invasive fungal infection

BACKGROUND

A variety of antifungal drugs, drug preparations and drug combinations are available to treat newborn infants with suspected or confirmed invasive fungal infection. There is a need to assess their relative merits.

OBJECTIVES

To assess the effect of treatment with different antifungal drugs, drug preparations or drug combinations on mortality and morbidity in newborn infants with suspected or confirmed invasive fungal infection.

SEARCH METHODS

We used the standard search strategy of the Cochrane Neonatal Review Group. This included searches of the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2012, Issue 2), MEDLINE, EMBASE, CINAHL (to March 2012), conference proceedings and previous reviews.

SELECTION CRITERIA

Randomised and quasi-randomised control trials comparing one antifungal agent or combination of agents with another in newborn infants with suspected or confirmed invasive fungal infection.

DATA COLLECTION AND ANALYSIS

We extracted the data using the standard methods of the Cochrane Neonatal Review Group, with separate evaluation of trial quality and data extraction by each author, and synthesis of data using risk ratio and risk difference.

MAIN RESULTS

We identified only one small trial in which 24 newborn infants participated. This trial compared the use of fluconazole versus amphotericin B (plus 5-fluorocytosine if fungal meningitis present). The trial did not detect a statistically significant effect on mortality (risk ratio 0.73; 95% confidence interval 0.26 to 2.05).

AUTHORS' CONCLUSIONS

There are insufficient data to inform practice. Large randomised controlled trials are required to compare antifungal drugs, drug preparations or drug combinations for treating newborn infants with invasive fungal infection.

Treatment of candidemia in adult patients without neutropenia--an inconvenient truth

In 2009 the Infectious Diseases Society of America reviewed the guidelines on the treatment of candidemia in non-neutropenic patients. In this document the preferred treatment was either fluconazole or an echinocandin. Amphotericin-B formulations were considered an alternative. However, careful assessment of published data showed similar efficacy between these drugs.

Antifungal therapy in infants and children with proven, probable or suspected invasive fungal infections

BACKGROUND

Invasive fungal infections are associated with significant morbidity and mortality in children. Optimal treatment strategies are yet to be defined.

OBJECTIVES

This review aims to systematically identify and summarise the effects of different antifungal therapies in children with proven, probable or suspected invasive fungal infections.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 3), MEDLINE (1966 to September 2008), EMBASE (1980 to September 2008) and CINAHL (1988 to September 2008) without language restrictions. We also handsearched reference lists and abstracts of conference proceedings and scientific meetings, and contacted authors of included studies and pharmaceutical manufacturers.

SELECTION CRITERIA

We included randomised clinical trials (RCTs) comparing a systemic antifungal agent with a comparator (including placebo) in children (one month to 16 years) with proven, probable or suspected invasive fungal infection.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied selection criteria, performed quality assessment, and extracted data using an intention-to-treat approach. We synthesised data using the random-effects model and expressed results as relative risks (RR) with 95% confidence intervals (CIs).

MAIN RESULTS

We included seven trials of antifungal agents in children with prolonged fever and neutropenia (suspected fungal infection) and candidaemia or invasive candidiasis (proven fungal infection). Four trials compared a lipid preparation of amphotericin B with conventional amphotericin B (395 participants), one trial compared an echinocandin with a lipid preparation of amphotericin B (82 participants) in suspected infection; one trial compared an echinocandin with a lipid preparation of amphotericin B in children with candidaemia or invasive candidiasis (109 participants) and one trial compared different azole antifungals in children with candidaemia (43 participants). No difference in all-cause mortality and other primary endpoints (mortality related to fungal infection or complete resolution of fungal infections) were observed. No difference in breakthrough fungal infection was observed in children with prolonged fever and neutropenia.When lipid preparations and conventional amphotericin B were compared in children with prolonged fever and neutropenia, nephrotoxicity was less frequently observed with a lipid preparation (RR 0.43, 95% CI 0.21 to 0.90, P = 0.02) however substantial heterogeneity was observed (I(2) = 59%, P = 0.06). Children receiving liposomal amphotericin B were less likely to develop infusion-related reactions compared with conventional amphotericin B (chills: RR 0.37, 95% CI 0.21 to 0.64, P = 0.0005). Children receiving a colloidal dispersion were more likely to develop such reactions than with liposomal amphotericin B (chills: RR 1.76, 95% CI 1.09 to 2.85, P = 0.02). The rate of other clinically significant adverse reactions attributed to the antifungal agent (total reactions; total reactions leading to treatment discontinuation, dose reduction or change in therapy; hypokalaemia and hepatotoxicity) were not significantly different. When echinocandins and lipid preparations were compared, the rate of clinically significant adverse reactions (total reactions; total reactions leading to treatment discontinuation, dose reduction or change in therapy) were not significantly different.

AUTHORS' CONCLUSIONS

Limited paediatric data are available comparing antifungal agents in children with proven, probable or suspected invasive fungal infection. No differences in mortality or treatment efficacy were observed when antifungal agents were compared. Children are less likely to develop nephrotoxicity with a lipid preparation of amphotericin B compared with conventional amphotericin B. Further comparative paediatric antifungal drug trials and epidemiological and pharmacological studies are required highlighting the differences between neonates, children and adults with invasive fungal infections.

Antifungal treatment for invasive Candida infections: a mixed treatment comparison meta-analysis

OBJECTIVES

Invasive fungal infections are a major cause of mortality among patients at risk. Treatment guidelines vary on optimal treatment strategies. We aimed to determine the effects of different antifungal therapies on global response rates, mortality and safety.

METHODS

We searched independently and in duplicate 10 electronic databases from inception to May 2009. We selected any randomized trial assessing established antifungal therapies for confirmed cases of invasive candidiasis among predominantly adult populations. We performed a meta-analysis and then conducted a Bayesian mixed treatment comparison to differentiate treatment effectiveness. Sensitivity analyses included dosage forms of amphotericin B and fluconazole compared to other azoles.

RESULTS

Our analysis included 11 studies enrolling a total of 965 patients. For our primary analysis of global response rates, we pooled 7 trials comparing azoles to amphotericin B, Relative Risk [RR] 0.87 (95% Confidence Interval [CI], 0.78-0.96, P = 0.007, I2 = 43%, P = 0.09. We also pooled 2 trials of echinocandins versus amphotericin B and found a pooled RR of 1.10 (95% CI, 0.99-1.23, P = 0.08). One study compared anidulafungin to fluconazole and yielded a RR of 1.26 (95% CI, 1.06-1.51) in favor of anidulafungin. We pooled 7 trials assessing azoles versus amphotericin B for all-cause mortality, resulting in a pooled RR of 0.88 (95% CI, 0.74-1.05, P = 0.17, I2 = 0%, P = 0.96). Echinocandins versus amphotericin B (2 trials) for all-cause mortality resulted in a pooled RR of 1.01 (95% CI, 0.84-1.20, P = 0.93). Anidulafungin versus fluconazole resulted in a RR of 0.73 (95% CI, 0.48-1.10, P = 0.34). Our mixed treatment comparison analysis found similar within-class effects across all interventions. Adverse event profiles differed, with amphotericin B exhibiting larger adverse event effects.

CONCLUSION

Treatment options appear to offer preferential effects on response rates and mortality. When mycologic data are available, therapy should be tailored.

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.

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.

Invasive fungal infection in very low birthweight infants: national prospective surveillance study

OBJECTIVE

To describe the epidemiology of invasive fungal infection in very low birthweight (VLBW: <1500 g) infants in the United Kingdom.

DESIGN

National prospective surveillance study between February 2003 and February 2004 using the British Paediatric Surveillance Unit reporting system reconciled with cases identified through routine laboratory reporting to the Health Protection Agency (England, Wales, and Northern Ireland), the Scottish Centre for Infection and Environmental Health, and the UK Mycology Reference Laboratory.

RESULTS

Ninety four confirmed cases of invasive fungal infection were identified during the surveillance period giving an incidence of estimated annual incidence of 10.0 (95% confidence interval (CI) 8.0 to 12.0) cases per 1000 VLBW live births. Eighty one (86%) of the infants were of extremely low birth weight (ELBW: <1000 g), incidence 21.1 (95% CI 16.5 to 25.7) per 1000 ELBW live births. Candida species, predominantly C albicans and C parapsilosis, were isolated in 93% of cases. Most organisms were isolated from the bloodstream and urinary tract. Death occurred in 41% of the infected infants before 37 weeks postconceptional age.

CONCLUSIONS

The incidence of invasive fungal infection in VLBW and ELBW infants in the United Kingdom is lower than reported in previous studies from tertiary centres in North America and elsewhere. The associated late neonatal and post-neonatal death rates are substantially higher than expected in infants without invasive fungal infection. These data may inform decisions about the evaluation and use of antifungal infection control strategies.

Voriconazole versus amphotericin B in cancer patients with neutropenia

BACKGROUND

Opportunistic fungal infections are a major cause of morbidity and mortality in neutropenic cancer patients and antifungal therapy are used both empirically and therapeutically in these patients.

OBJECTIVES

To compare the benefits and harms of voriconazole with those of amphotericin B and fluconazole when used for prevention or treatment of invasive fungal infections in cancer patients with neutropenia.

SEARCH STRATEGY

MEDLINE and the Cochrane Library (May 2005). Letters, abstracts and unpublished trials were accepted. Contact to authors and industry.

SELECTION CRITERIA

Randomised trials comparing voriconazole with amphotericin B or fluconazole.

DATA COLLECTION AND ANALYSIS

Data on mortality, invasive fungal infection, colonisation, use of additional (escape) antifungal therapy and adverse effects leading to discontinuation of therapy were extracted by two authors independently.

MAIN RESULTS

Two trials were included. One trial compared voriconazole to liposomal amphotericin B as empirical treatment of fever of unknown origin (suspected fungal infections) in neutropenic cancer patients (849 patients, 58 deaths). The other trial compared voriconazole to amphotericin B deoxycholate in the treatment of confirmed and presumed invasive Aspergillus infections (391 patients, 98 deaths). In the first trial, voriconazole was significantly inferior to liposomal amphotericin B according to the authors' prespecified criteria. More patients died in the voriconazole group and a claimed significant reduction in the number of breakthrough fungal infections disappeared when patients arbitrarily excluded from analysis by the authors were included. In the second trial, the deoxycholate preparation of amphotericin B was used without any indication of the use of premedication and substitution with electrolytes and salt water to avoid handicapping this drug. This choice of comparator resulted in a marked difference in the duration of treatment on trial drugs (77 days with voriconazole versus 10 days with amphotericin B), and precludes meaningful comparisons of the benefits and harms of the two drugs.

AUTHORS' CONCLUSIONS

Liposomal amphotericin B is significantly more effective than voriconazole for empirical therapy of neutropenic cancer patients and should be preferred. For treatment of aspergillosis, there are no trials that have compared voriconazole with amphotericin B given under optimal conditions.

Flaws in design, analysis and interpretation of Pfizer's antifungal trials of voriconazole and uncritical subsequent quotations

We have previously described how a series of trials sponsored by Pfizer of its antifungal drug, fluconazole, in cancer patients with neutropenia handicapped the control drug, amphotericin B, by flaws in design and analysis. We describe similar problems in two pivotal trials of Pfizer's new antifungal agent, voriconazole, published in a prestigious journal. In a non-inferiority trial, voriconazole was significantly inferior to liposomal amphothericin B, but the authors concluded that voriconazole was a suitable alternative. The second trial used amphothericin B deoxycholate as comparator, but handicapped the drug by not requiring pre-medication to reduce infusion-related toxicity or substitution with electrolytes and fluid to reduce nephrotoxicity, although the planned duration of treatment was 84 days. Voriconazole was given for 77 days on average, but the comparator for only 10 days, which precludes a meaningful comparison. In a random sample of 50 references to these trials, we found that the unwarranted conclusions were mostly uncritically propagated. It was particularly surprising that relevant criticism raised by the FDA related to the first trial was only quoted once, and that none of the articles noted the obvious flaws in the design of the second trial. We suggest that editors ensure that the abstract reflects fairly on the remainder of the paper, and that journals do not impose any time limit for accepting letters that point out serious weaknesses in a study that have not been noted before.

Caspofungin for invasive fungal infections: combination treatment with liposomal amphotericin B in children undergoing hemopoietic stem cell transplantation

Invasive fungal infections often prove difficult to eradicate especially in the stem cell transplant setting. Amphotericin has been the mainstay of treatment for years but has significant toxicity. Newer antifungal agents, such as caspofungin, have shown promising results in adults, particularly when used in combination with amphotericin as both drugs differ in their mode of action. However, there are few data from children and no previous published information about the use of Caspofungin after paediatric stem cell transplantation. We report our experience in children with proven invasive fungal infections after stem cell transplantation. This combination was non-toxic, and two of three patients survived their infections.

A systematic review of the antifungal effectiveness and tolerability of amphotericin B formulations

OBJECTIVE

A systematic review was performed to compare the effectiveness and tolerability of lipid-based amphotericin B (AmB) formulations and conventional AmB in the treatment of systemic fungal infections.

METHODS

The literature and unpublished studies were searched using MEDLINE, EMBASE, Biological Abstracts, AIDSLINE, CANCERLIT, CRD database, Cochrane Controlled Trials Register, and other databases. Search terms included: amphotericin, liposom*, lipid*, colloid*, antifungal agents, and mycoses. Studies were selected according to predetermined criteria. The outcome measures reviewed were efficacy, mortality, renal toxicity, and infusion-related reactions. Meta-analyses and number-needed-to-treat (NNT) analyses were performed.

RESULTS

Seven studies (8 publications) met the entry criteria. Meta-analysis showed that lipid-based formulations significantly reduced all-cause mortality risk by an estimated 28% compared with conventional AmB (odds ratio [OR], 0.72; 95% CI, 0.54 to 0.97). There was no significant difference in efficacy between the lipid-based formulations and conventional AmB (OR, 1.21; 95% CI, 0.98 to 1.49). AmB lipid complex (ABLC) and liposomal AmB (L-AmB) significantly reduced the risk of doubling serum creatinine by an estimated 58% (OR, 0.42; 95% CI, 0.33 to 0.54). There was no significant reduction in risk of infusion-related reactions with lipid-based formulations, although this was difficult to interpret given the lack of consistent control of confounding factors. Comparing the lipid-based formulations with conventional AmB, the overall NNT to prevent 1 death was 31. The NNT to prevent a doubling of serum creatinine for both ABLC and L-AmB compared with conventional AmB was 6.

CONCLUSIONS

This study demonstrates advantages with lipid-based formulations over conventional AmB in terms of reduced risk of mortality and renal toxicity. Future trials in patients with proven fungal infection should control for factors such as premedication, infusion rates, fluid preloading, sodium/potassium supplementation, and concomitant medication.

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.

Amphotericin B lipid soluble formulations vs amphotericin B in cancer patients with neutropenia

BACKGROUND

Patients with cancer who are treated with chemotherapy or receive a bone marrow transplant have an increased risk of acquiring fungal infections. Such infections can be life-threatening. Antifungal drugs are therefore often given prophylactically to such patients, or when they have a fever.

OBJECTIVES

To compare the effect and adverse effects of AmBisome and other lipid soluble formulations of amphotericin B with conventional amphotericin B in cancer patients with neutropenia.

SEARCH STRATEGY

MEDLINE and Cochrane Library. Unpublished trials from conference proceedings and contact to industry.

SELECTION CRITERIA

Randomised trials comparing lipid soluble formulations of amphotericin B with conventional amphotericin B.

DATA COLLECTION AND ANALYSIS

Data on mortality, invasive fungal infection, nephrotoxicity, serum creatinine and dropouts were extracted by both authors independently.

MAIN RESULTS

AmBisome vs conventional amphotericin B (3 trials, 1149 patients): AmBisome tended to be more effective than conventional amphotericin B for invasive fungal infection (relative risk 0.63, 95% confidence interval 0.39 to 1.01, P=0.053) whereas there was no significant difference in mortality (relative risk 0.74, 95% CI 0.52 to 1.07). AmBisome decreased significantly the incidence of nephrotoxicity, defined as a 100% increase in serum creatinine (relative risk 0.51, 95% CI 0.40 to 0.64). Fewer patients dropped out on AmBisome but the difference was not significant (relative risk 0.78, 95% CI 0.56 to 1. 08). Amphotericin B in Intralipid vs conventional amphotericin B (4 trials, 145 patients): There were no significant differences in clinical effect whereas the patients treated with the lipid soluble formulation experienced significantly less nephrotoxicity (relative risk 0.34, 95% CI 0.15 to 0.75) and smaller increases in serum creatinine (weighted mean difference 32 micromol/l, 95% CI 21 to 43 micromol/l). Amphotericin B colloidal dispersion (ABCD) vs conventional amphotericin B (1 trial, 213 patients): There was lower nephrotoxicity with ABCD (relative risk 0.38, 95% CI 0.25 to 0.59).

REVIEWER'S CONCLUSIONS

AmBisome is a better drug than conventional amphotericin B but its high cost prohibits routine use in most settings. Furthermore, the advantages of AmBisome may be smaller than indicated in our review if conventional amphotericin B is administered under optimal circumstances. It is not clear whether other lipid formulations of amphotericin B could offer a worthwhile advantage compared to conventional amphotericin B.