Safety and toxicity of amphotericin B in glucose 5% or intralipid 20% in neutropenic patients with pneumonia or fever of unknown origin: randomised study

Outpatient parenteral antifungal therapy (OPAT) for invasive fungal infections with intermittent dosing of liposomal amphotericin B

Triazole resistant A. fumigatus has been documented in many parts of the world. In the Netherlands, incidence is now above 10% and results in the need for long-term parenteral therapy with liposomal amphotericin B (LAmB). The long terminal half-life of LAmB suggests that intermittent dosing could be effective, making the application of outpatient antifungal therapy (OPAT) possible. Here, we report our experience with the use of OPAT for Invasive Fungal Infections (IFI). All adult patients treated with LAmB with a 2 or 3 times weekly administration via the outpatient departments in four academic tertiary care centers in the Netherlands and Belgium since January 2010 were included in our analysis. Patient characteristics were collected, as well as information about diagnostics, therapy dose and duration, toxicity, treatment history and outcome of the IFI. In total, 18 patients were included. The most frequently used regimen (67%) was 5 mg/kg 3 times weekly. A partial response to the daily treatment prior to discharge was confirmed by CT-scan in 17 (94%) of patients. A favorable outcome was achieved in 13 (72%) patients. Decrease in renal function occurred in 10 (56%) cases but was reversible in all and was treatment limiting in one patient only. The 100-day mortality and 1-year mortality after initiation of OPAT were 0% and 6%, respectively. In a selected population, and after confirmation of initial response to treatment, our data support the use of OPAT with LAmB for treatment of IFI in an intermittent dosing regimen.

Efficacy of Intralipid infusion in reducing amphotericin-B-associated nephrotoxicity in head and neck invasive fungal infection: A randomized, controlled trial

Amphotericin B deoxycholate (ABD) is the best therapeutic agent available for the treatment of most systemic fungal infections. However, some untoward adverse effects such as nephrotoxicity may limit its appropriate therapeutic use. We conducted a randomized, controlled trial ofthe infusion of fat emulsion (Intralipid) shortly after the infusion of ABD to evaluate its effects on reducing ABD-associated nephrotoxicity. Our patient population was made up of 31 patients who were randomized into two groups: an intervention group (n = 16) and a control group (15 patients). There were no statistically significant differences between the two groups in demographic or clinical variables. All patients received 1mg/kg/day of ABD in dextrose 5%. In addition, the patients in the intervention arm received Intralipid 10%, which was started as soon as possible within 1 hour after the infusion of ABD. ABD-associated nephrotoxicity was defined as a minimum 50% increase in baseline serum creatinine to a minimum of 2mg/dl. We also measured daily serum creatinine changes during the first 2 weeks of treatment, and we compared some other relevant indices of renal function, as well as ABD-related hypokalemia. We found no statistically significant differences between the two treatments in terms of ABD-associated nephrotoxicity or any of the other indices. We conclude that the administration of Intralipid 10% early after infusion of ABD in dextrose 5% does not have any effect in decreasing ABD-associated nephrotoxicity or hypokalemia.

Efficacy and safety of amphotericin B formulations: a network meta-analysis and a multicriteria decision analysis

Objectives

Despite its broad spectrum, conventional amphotericin B (AB) is associated with serious adverse events. Lipid-based formulations may offer safer options. We aimed to synthesize the evidence of efficacy and safety of AB formulations.

Methods

We performed a systematic review and network meta-analysis (NMA) to compare all available formulations: conventional AB; lipid complex or ABLC; colloidal dispersion or ABCD; liposomal or LAB; AB in Intralipid. Randomized controlled trials were searched in four databases. Cure, fever, chills, nephrotoxicity, death and drug discontinuation were assessed. NMA was based on Bayesian methods accounting for direct and indirect comparisons. Probability ranks estimating the best formulation were built for each outcome. The relative benefit–risk of formulations was assessed with stochastic multicriteria acceptability analyses (SMAA).

Key findings

We identified 25 trials (n = 2996). No significant differences among drugs were observed for cure or death. All lipid-based formulations were safer than conventional AB for nephrotoxicity. AB-Intralipid was more tolerable than conventional AB and caused less chills than ABCD. AB-Intralipid was the best therapy (>60%) regarding nephrotoxicity, fever, chills and discontinuation. The scenario from SMAA favoured AB-Intralipid (81% acceptability). Conventional AB was secondary to all lipid-based formulations.

Conclusions

Amphotericin B-Intralipid was identified as safer, cost-saving treatment in comparison with other formulations.

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.

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.

Diagnosis and therapy of Candida infections: joint recommendations of the German Speaking Mycological Society and the Paul-Ehrlich-Society for Chemotherapy

Invasive Candida infections are important causes of morbidity and mortality in immunocompromised and hospitalised patients. This article provides the joint recommendations of the German-speaking Mycological Society (Deutschsprachige Mykologische Gesellschaft, DMyKG) and the Paul-Ehrlich-Society for Chemotherapy (PEG) for diagnosis and treatment of invasive and superficial Candida infections. The recommendations are based on published results of clinical trials, case-series and expert opinion using the evidence criteria set forth by the Infectious Diseases Society of America (IDSA). Key recommendations are summarised here: The cornerstone of diagnosis remains the detection of the organism by culture with identification of the isolate at the species level; in vitro susceptibility testing is mandatory for invasive isolates. Options for initial therapy of candidaemia and other invasive Candida infections in non-granulocytopenic patients include fluconazole or one of the three approved echinocandin compounds; liposomal amphotericin B and voriconazole are secondary alternatives because of their less favourable pharmacological properties. In granulocytopenic patients, an echinocandin or liposomal amphotericin B is recommended as initial therapy based on the fungicidal mode of action. Indwelling central venous catheters serve as a main source of infection independent of the pathogenesis of candidaemia in the individual patients and should be removed whenever feasible. Pre-existing immunosuppressive treatment, particularly by glucocorticosteroids, ought to be discontinued, if feasible, or reduced. The duration of treatment for uncomplicated candidaemia is 14 days following the first negative blood culture and resolution of all associated symptoms and findings. Ophthalmoscopy is recommended prior to the discontinuation of antifungal chemotherapy to rule out endophthalmitis or chorioretinitis. Beyond these key recommendations, this article provides detailed recommendations for specific disease entities, for antifungal treatment in paediatric patients as well as a comprehensive discussion of epidemiology, clinical presentation and emerging diagnostic options of invasive and superficial Candida infections.

Acute kidney injury

INTRODUCTION

Acute renal failure is characterised by abrupt and sustained decline in glomerular filtration rate, which leads to accumulation of urea and other chemicals in the blood. The term acute kidney injury has been introduced to encompass a wide spectrum of acute alterations in kidney function from mild to severe. Acute kidney injury is classified according to the RIFLE criteria, in which a change from baseline serum creatinine or urine output determines the level of renal dysfunction.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to prevent acute kidney injury in people at high risk? What are the effects of treatments for critically ill people with acute kidney injury? We searched: Medline, Embase, The Cochrane Library, and other important databases up to December 2009 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 82 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: albumin supplementation plus loop diuretics (intravenous), aminoglycosides, aminophylline, amphotericin B, calcium channel blockers, contrast media, dialysis membranes, dopamine, early versus late dialysis, extended daily dialysis, fenoldopam, loop diuretics, mannitol, N-acetylcysteine, natriuretic peptides, renal replacement therapy, sodium bicarbonate-based fluids, sodium chloride-based fluids, and theophylline.

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.

Reduction of amphotericin B-induced renal tubular apoptosis by N-acetylcysteine

The reduction of amphotericin B (AmB)-induced renal tubular apoptosis and nephrotoxicity by N-acetylcysteine (NAC) in a murine model was evaluated. Four groups of rats were treated with AmB for 5 days, and each group concomitantly received two doses of 30, 60, or 120 mg of NAC/kg of body weight/day or sterile water for 5 days. Groups that received concomitant NAC at any dose had significantly decreased levels of apoptosis compared to that in animals receiving AmB only (48.8% versus 27.4, 23.6, or 23.5%, respectively; P < 0.001).

Acute renal failure

INTRODUCTION

Acute renal failure is characterised by abrupt and sustained decline in glomerular filtration rate, which leads to accumulation of urea and other chemicals in the blood. The term acute kidney injury has been recently introduced to encompass a wide spectrum of acute alterations in kidney function from very mild to severe. Acute renal failure/acute kidney injury is classified according to the RIFLE criteria where a change from baseline serum creatinine or urine output determines the level of renal dysfunction.

METHODS AND OUTCOMES

We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to prevent acute renal failure in people at high risk? What are the effects of treatments for critically ill people with acute renal failure? We searched: Medline, Embase, The Cochrane Library, and other important databases up to April 2007 (BMJ Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).

RESULTS

We found 77 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.

CONCLUSIONS

In this systematic review we present information relating to the effectiveness and safety of the following interventions: albumin supplementation plus loop diuretics (intravenous), aminoglycosides, aminophylline, amphotericin B, calcium channel blockers, contrast media, dialysis membranes, dopamine, fenoldopam, loop diuretics, mannitol, N-acetylcysteine, natriuretic peptides, renal replacement therapy, sodium bicarbonate-based fluids, sodium chloride-based fluids, and theophylline.

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.

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.

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.

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

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

Challenges and solutions for the delivery of biotech drugs – a review of drug nanocrystal technology and lipid nanoparticles

Biotechnology allows tailor-made production of biopharmaceuticals and biotechnological drugs; however, many of them require special formulation technologies to overcome drug-associated problems. Such potential challenges to solve are: poor solubility, limited chemical stability in vitro and in vivo after administration (i.e. short half-life), poor bioavailability and potentially strong side effects requiring drug enrichment at the site of action (targeting). This review describes the use of nanoparticulate carriers, developed in our research group, as one solution to overcome such delivery problems, i.e. drug nanocrystals, solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC) and lipid-drug conjugate (LDC) nanoparticles, examples of drugs are given. As a recently developed targeting principle, the concept of differential protein adsorption is described (PathFinder Technology) using as example delivery to the brain.

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

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

Amphotericin B nephrotoxicity in children

Amphotericin B is the treatment of choice for severe systemic fungal infections. Nephrotoxicity is the most clinically significant adverse effect, but studies examining nephrotoxicity in children are scarce. Nephrotoxicity includes decreased glomerular filtration rate and distal tubulopathy with urinary loss of potassium and magnesium, renal tubular acidosis, loss of urine concentrating ability, and sometimes Fanconi's syndrome. The mechanisms involved in nephrotoxicity include the use of deoxycholate, the vehicle for amphotericin, reduction in renal blood flow and glomerular filtration rate, increased salt concentrations at the macula densa, interaction of amphotericin with ergosterol in the cell membrane, and apoptosis in proximal tubular cells and medullary interstitial cells. Some risk factors for amphotericin nephrotoxicity have been determined over the years. Cumulative dosage, treatment duration, and dosing schedule as well as the combination of amphotericin with other nephrotoxic drugs, such as diuretics and cyclosporine, are important risk factors. Mechanisms to prevent nephrotoxicity include the use of lipid formulations such as amphotericin B lipid complex, amphotericin B colloidal dispersion, and liposomal amphotericin B and the concurrent use of volume repletion. Amiloride can be considered in serious potassium loss.

Early diagnosis of candidiasis in non-neutropenic critically ill patients

OBJECTIVE

To determine a method for the early diagnosis of candidiasis in non-neutropenic critically ill patients in order to reduce mortality.

METHODS

A prospective study in non-neutropenic critically patients in whom Candida spp. were detected, was made in an intensive care unit (ICU) during an 8-year period from 3389 patients admitted. A diagnostic and therapeutic protocol was designed. Invasive candidiasis was defined according to dissemination and multifocality.

RESULTS

Candida spp. were found in 145 cases (4.3%): 120 (83%) were considered as invasive candidiasis and 25 as colonisation (17%). The hospital mortality was 46% (67/145). A post-mortem study was carried out in 54% (36/67) of hospital deaths. Candida albicans was the most frequently isolated species (87%), followed by Candida glabrata (18%). There were 24 candidemias and three cases of endophtalmitis. Digestive and respiratory samples and non-C. albicans yeasts were risk factors for invasive candidiasis. The mortality rate was related statistically to invasive candidiasis and inversely to the appropriate antifungal treatment.

CONCLUSIONS

Invasive candidiasis is related to digestive and respiratory samples and to the presence of non-C. albicans species. A simpler definition of invasive candidiasis in non-neutropenic critically ill patients will permit more rapid and accurate specific antifungal therapy.

The lipid formulations of amphotericin B

Amphotericin B spectrum covers most of the fungal pathogens involved in human diseases. Its use is limited by infusion-related effects and nephrotoxicity. As a result of strong lipophilic properties, encapsulation in liposomes or binding to lipid complexes led to the development of lipid formulations in an attempt to increase both efficacy and safety. Three lipid formulations of amphotericin B are commercially available: a liposomal preparation, a lipid complex and a colloidal dispersion. They differ in their lipid composition, shape, pharmacokinetic behaviour and clinical effects. The nephrotoxicity of these formulations is significantly decreased compared to their parent compound. Infusion-related events are lowest with liposomal amphotericin B. Increased efficacy of the lipid formulations over conventional amphotericin B, however, still has to be demonstrated. These formulations are mainly indicated for the treatment of documented fungal infections in patients failing conventional amphotericin B or with renal impairment. Liposomal amphotericin B is also indicated for empirical therapy of suspected fungal infections in febrile neutropenic patients giving this compound an advantage over the two other formulations. Lipid formulations of amphotericin B are extremely expensive. Whether the increase in cost translates into a long-term benefit for the patient is still unknown.

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/emulsion admixture interactions: an approach concerning the reduction of amphotericin B toxicity

Mixing Fungizone with a fat emulsion used for nutritional purpose (Intralipid or Lipofundin ) was reported to decrease Amphotericin B (AmB) toxicity in clinical use. In an effort to understand the reason for this phenomenon, spectral and morphological analyses were done for the Fungizone and Fungizone /Lipofundin admixture (FLmix). The absorption spectra analyses showed that not only Fungizone but also FLmix presented spectra that were concentration dependent. Moreover, the spectra of FLmix remained stable until the concentration of 5 x 10(-7) M, and only at 5 x 10(-8) M did they become similar in shape to the Fungizone spectra. Morphological studies revealed that even though emulsion droplets with or without Fungizone presented the same particle size, the former was less electron dense compared with Lipofundin alone. These results suggest a kind of association between Fungizoneand Lipofundin that remains over the whole range of concentrations. This hypothesis was confirmed by in vitro studies in which FLmix presented an important selectivity against human and fungal cells compared with Fungizone. These findings suggest that parenteral emulsions should be able to reduce the AmB toxicity probably by changing the AmB self-association state by binding it with emulsion droplets.

Amphotericin B and liver function

Amphotericin B is well established as a highly efficacious agent against systemic fungal infections in humans. The therapeutic potential of amphotericin B is limited due to its side effects. Although in clinical use for more than 35 years, impairment of liver function is not considered to be a typical adverse effect of amphotericin B. Experimental data suggest that the drug may interfere with the hepatic cytochrome P450 and may thus influence the metabolic capacity of the liver. A confirmation of such a finding in patients treated with amphotericin B would be of value. The incidence of severe acute or subacute hepatotoxicity in response to amphotericin B is very low. Frequently, in critically ill patients, it is not always clear whether liver abnormalities are caused by an antifungal agent or whether they are due to the critical condition of these patients. Nevertheless, there are experimental data suggesting that amphotericin B may influence the metabolic capacity of the liver. Accordingly, drug interactions during prolonged amphotericin B treatment seem possible. Careful monitoring of liver function in those patients receiving amphotericin B in combination with other drugs, which undergo hepatic metabolism or are potentially hepatotoxic, is recommended. In this review, the current understanding and knowledge of the clinical significance, detection, and possible pathogenesis of amphotericin-B-induced liver damage are presented. With respect to the current experimental data, the influence of the drug on the hepatic microsomal cytochrome P450 are also presented and discussed, as is the impact of several clinical studies using different amphotericin B formulas in humans.

Can we decrease amphotericin nephrotoxicity?

Amphotericin B (AmB) is considered the drug of choice for the treatment of systemic fungal infections. Nephrotoxicity is a major complication associated with its use, and appears to be related to higher cumulative doses, diuretic use, abnormal serum creatinine at baseline, and the use of concomitant nephrotoxic drugs. The two major hypotheses for the pathogenesis of AmB-related nephrotoxicity are direct effects of the drug on epithelial cell membranes and vasoconstriction. During the last few years, some randomized trials have tested different strategies to reduce AmB-induced renal toxicity. These strategies include sodium supplementation, low-dose dopamine, slower infusion rates, the administration of AmB in lipid emulsions, and in lipid formulations. The results of these trials showed that the lipid formulations of AmB significantly reduce nephrotoxicity. Unfortunately, these agents are costly, restricting their use to patients with a high risk of developing renal failure.

Pulmonary reactions during treatment with amphotericin B: review of published cases and guidelines for management

Acute respiratory events occasionally have been observed during the infusion of amphotericin B. Herein we analyze the 21 cases that have been reported, including a fatal reaction observed by us. Some useful guidelines are provided that likely will allow treatment to be continued safely for patients who have experienced such reactions.

Comparison of effects of amphotericin B deoxycholate infused over 4 or 24 hours: randomised controlled trial

OBJECTIVE

To test the hypothesis that amphotericin B deoxycholate is less toxic when given by continuous infusion than by conventional rapid infusion.

DESIGN

Randomised, controlled, non-blinded, single centre study.

SETTING

University hospital providing tertiary clinical care.

PATIENTS

80 mostly neutropenic patients with refractory fever and suspected or proved invasive fungal infections.

INTERVENTION

Patients were randomised to receive 0.97 mg/kg amphotericin B by continuous infusion over 24 hours or 0.95 mg/kg by rapid infusion over four hours.

MAIN OUTCOME MEASURES

Patients were evaluated for side effects related to infusion, nephrotoxicity, and mortality up to three months after treatment. Analysis was on an intention to treat basis.

RESULTS

Patients in the continuous infusion group had fewer side effects and significantly reduced nephrotoxicity than those in the rapid infusion group. Overall mortality was higher during treatment and after three months' follow up in the rapid infusion than in the continuous infusion group.

CONCLUSION

Continuous infusions of amphotericin B reduce nephrotoxicity and side effects related to infusion without increasing mortality.

Lipid-based amphotericin B: a review of the last 10 years of use

The last decade has been remarkable for the dramatic increase in the prevalence of serious fungal infections in patients with haematological disorders and neutropenic cancer patients. The mortality rate of deep-seated infection has been in excess of 90% and there is no doubt that this is one of the greatest challenges currently facing haematologists and oncologists. The development of the lipid-based drugs - liposomal amphotericin (AmBisome(R)), amphotericin B lipid complex, ABLC (Abelcet(R)), amphotericin B colloidal dispersion, Amphocil (ABCD(R)), has meant that doses of amphotericin B can be safely escalated for the first time whilst the problems of nephrotoxicity, infusion related reactions (including chills, rigors, fevers and hypoxia) can be reduced. These toxicities are variably reduced with AmBisome more than Abelcet and more than Amphocil and there is little information from randomised trials other than for AmBisome. AmBisome used in the setting of persistent fever and neutropenia not responding after 3-4 days of intravenous antibiotics, is associated with less breakthrough systemic fungal infections. There is also much less need for premedication, including steroids, compared with amphotericin B and Abelcet. The use of intermittent doses of Ambisome given prophylactically is now being explored. A new and exciting era of antifungal therapy is opening up with new compounds, such as itraconazole voriconazole, posaconazole and echinocandins, being investigated and for the first time, we also have options for combination therapy and prophylaxis.

[New lipid formulations of amphotericin B. Review of the literature]

INTRODUCTION

Amphotericin B (amB) remains the gold standard for treatment of invasive fungal infections. Lipid formulations of amB have been developed in an attempt to improve both efficacy and tolerability (especially renal toxicity): amB lipid complex (ABLC), liposomal amB (AmBisome), amB colloidal dispersion (ABCD) and amB in lipid emulsion (Intralipid). This review analyzes the data available in the literature.

CURRENT KNOWLEDGE AND KEY POINTS

ABLC, AmBisome and ABCD are effective in various fungal infections, including invasive aspergillosis, systemic candidiasis, cryptococcal meningitis, mucormycosis and fusariosis. These formulations are also effective in persistent febrile neutropenia and in leishmaniosis. The three formulations show little renal toxicity and are safer than conventional amB in this respect. Preliminary data are available on amB in Intralipid: infusion-related adverse effects are reduced, but few data are available on efficacy in documented mycoses.

FUTURE PROSPECTS AND PROJECTS

Large-scale comparative clinical trials may clarify issues of relative efficacy in various forms of fungal 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.

Amphotericin B and its new formulations: pharmacologic characteristics, clinical efficacy, and tolerability

Amphotericin B (amB) remains the gold standard for the treatment of invasive fungal infections. However, the efficacy is limited, with response rates from 10% to 80%. Moreover, amB is toxic, especially for the kidneys. New formulations have been developed in an attempt to improve both efficacy and tolerability. In an attempt to reduce toxicity, a number of investigators have reconstituted amB in a lipid emulsion, but few data are available on efficacy in documented infections. An improvement in immediate and renal tolerance was obtained with equivalent daily dose regimens, but the therapeutic index does not appear to be improved. This approach cannot be recommended at present. Three lipid formulations have been developed and are now available in most countries: amB colloidal dispersion (ABCD), amB lipid complex (ABLC), and liposomal amB (AmBisome). The efficacy of ABCD on various fungal infections has been assessed in open trials, with a response rate of 49% in aspergillosis, 70% in candidiasis, and 67% in mucormycosis. In two randomized trials comparing ABCD with amB in invasive aspergillosis and in persistent febrile neutropenia, the response rates were equivalent. ABCD was less nephrotoxic. In contrast, immediate reactions to ABCD were as frequent and severe as with amB. These immediate effects are more frequent during the first infusions and lessen as treatment continues. The recommended dose is 3-4 mg/kg/day. ABLC appeared to be effective as rescue therapy in various types of invasive mycoses, with a response rate of 42% in aspergillosis, 67% in candidiasis, and 82% in fusariosis. Efficacy identical to that of amB was demonstrated in a comparative randomized trial involving patients with invasive candidiasis. General and renal tolerability is improved compared with amB. The recommended dose regimen is 5 mg/kg/day. Liposomal amB (AmBisome) is the only truly liposomal formulation. The response rates in preliminary trials were 66% in aspergillosis and 81% in candidiasis. Several comparative studies have confirmed that this formulation has similar or superior efficacy relative to amB in various fungal infections and also in the empirical treatment of febrile neutropenia. Renal and general tolerability is excellent. The optimal dosing remains unclear but is generally between 3 and 5 mg/kg/day. A double-blind trial comparing the tolerance of liposomal amB and ABLC demonstrated that both infusion-related events and nephrotoxicity were significantly lower for liposomal amB. In sum, the new lipid formulations of amB are effective in various invasive fungal infections. The three formulations exhibit reduced nephrotoxicity compared with conventional amB. Large-scale comparative clinical trials may clarify issues of relative efficacy in various forms of mycotic infections.

A randomized prospective trial of amphotericin B lipid emulsion versus dextrose colloidal solution in critically ill patients

BACKGROUND

Amphotericin B is the agent of choice for most invasive fungal infections in critically ill patients. It is associated with at least a 50% incidence of nephrotoxicity, despite prophylactic measures such as sodium loading. Newer formulations of amphotericin B are available but are costly and have unknown bioavailability in critically ill patients. Previous trials in neutropenic and critically ill patients have demonstrated that mixing amphotericin B with 20% lipid solution (Intralipid; Clintec Nutrition, Deerfield, III) may decrease nephrotoxicity.

METHODS

In this randomized, prospective clinical trial, patients with positive fungal blood cultures, tracheal/sputum cultures or peritoneal cavity cultures were randomized to receive either 0.5 mg/kg per day of amphotericin B dextrose or 1.0 mg/kg per day of amphotericin B lipid emulsion. Duration of therapy was determined by the primary care team. Weekly 24-hour creatinine clearance was measured until 2 weeks after amphotericin B therapy was completed.

RESULTS

The two groups were similar based on age, white blood cell count, serum creatinine, and creatinine clearance at the beginning of therapy. The group receiving amphotericin B lipid emulsion had significantly less decrease in creatinine clearance compared with controls, despite receiving significantly more amphotericin B.

CONCLUSION

Amphotericin B lipid emulsion can be given at a higher total cumulative dose than amphotericin B dextrose with less nephrotoxicity.

Comparison of the toxicity of amphotericin B in 5% dextrose with that of amphotericin B in fat emulsion in a randomized trial with cancer patients

A multicentric randomized trial was undertaken to compare the toxicity of amphotericin B in 5% dextrose with that of amphotericin B in a fat emulsion (Intralipid) in cancer patients. Group 1 (n = 33) received amphotericin B diluted in 5% dextrose with premedication consisting of promethazine plus an antipyretic. Group 2 (n = 28) received amphotericin B diluted in 20% Intralipid without premedication. Amphotericin B was infused daily at a dose of 1 mg/kg of body weight over a 1-h period to members of both groups for empirical antifungal therapy (in neutropenic patients) or for the treatment of documented fungal infections. The majority of patients (80%) received empirical amphotericin B treatment. The two groups were comparable with regard to age, gender, underlying disease, and the following baseline characteristics: use of other nephrotoxic drugs and serum levels of potassium and creatinine. The median cumulative doses of amphotericin B were 240 mg in group 1 and 245 mg in group 2 (P = 0.73). Acute adverse events occurred in 88% of patients in group 1 and in 71% of those in group 2 (P = 0.11). Forty percent of the infusions in group 1 were associated with fever, compared to 23% in group 2 (P < 0.0001). In addition, patients in group 2 required less meperidine for the control of acute adverse events (P = 0.008), and fewer members of this group presented with hypokalemia (P = 0.004) or rigors (P < 0.0001). There was no difference in the proportions of patients with nephrotoxicity (P = 0.44). The success rates of empirical antifungal treatment were similar in the two groups (P = 0.9). Amphotericin B diluted in a lipid emulsion seems to be associated with a smaller number of acute adverse events and fewer cases of hypokalemia than amphotericin B diluted in 5% dextrose.

Amphotericin B in children with malignant disease: a comparison of the toxicities and pharmacokinetics of amphotericin B administered in dextrose versus lipid emulsion

In a prospective, randomized clinical trial, the toxicity of 1 mg of amphotericin B (AmB) per kg of body weight per day infused in 5% dextrose was compared with that of AmB infused in lipid emulsion in children with malignant disease. In an analysis of 82 children who received a full course of 6 days or more of AmB (117 courses), it was shown that there were significant increases in plasma urea and creatinine concentrations and in potassium requirement after 6 days of therapy with both AmB infused in dextrose and AmB infused in lipid emulsion, with there being no difference between the two methods of AmB administration. An intent-to-treat comparison of the numbers of courses affected by acute toxicity (fever, rigors) and chronic toxicity (nephrotoxicity) also indicated that there was no significant difference between AmB infused in dextrose (78 courses) and AmB infused in lipid emulsion (84 courses). The pharmacokinetics of AmB were investigated in 20 children who received AmB in dextrose and 15 children who received AmB in lipid emulsion. Blood samples were collected up to 24 h after administration of the first dose, and the concentration of AmB in plasma was analyzed by a high-performance liquid chromatography assay. The clearance (CL) of AmB in dextrose (0.039 +/- 0.016 liter. h-1. kg-1) was significantly lower (P < 0.005) than the CL of AmB in lipid emulsion (0.062 +/- 0. 024 liter. h-1. kg-1). The steady-state volume of distribution for AmB in dextrose (0.83 +/- 0.33 liter. kg-1) was also significantly lower (P < 0.005) than that for AmB in lipid emulsion (1.47 +/- 0.77 liter. kg-1). Although AmB in lipid emulsion is apparently cleared faster and distributes more widely than AmB in dextrose, this study did not reveal any significant advantage with respect to safety and tolerance in the administration of AmB in lipid emulsion compared to its administration in dextrose in children with malignant disease.

Lipid-based amphotericin B for the treatment of fungal infections

The frequency of life-threatening fungal infections has increased dramatically over the past few decades. For more than 30 years amphotericin B has been the standard treatment for systemic and deep-seated fungal infections, primarily because of its broad spectrum of activity. Its usefulness is limited by a relatively high frequency of significant adverse events including infusion-related reactions and nephrotoxicity. In an effort to overcome these side effects, a number of lipid-based formulations were developed, each with its own composition and pharmacokinetic behavior. The clinical significance of these differences is unknown. Available clinical data suggest the formulations have a reduced propensity for causing nephrotoxicity. However, considering limited efficacy data, they should be reserved as second-line therapy for patients who cannot tolerate or fail an adequate trial of conventional amphotericin B or cannot benefit from other antifungal agents.