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

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.

ESTRATÉGIAS TECNOLÓGICAS PARA FORMULAÇÕES DE ANFOTERICINA B EM SISTEMAS LIPÍDICOS DISPONÍVEIS NO MERCADO FARMACÊUTICO E OUTROS PROMISSORES SISTEMAS DE ADMINISTRAÇÃO

A anfotericina B (AmB) é um fármaco antifúngico utilizado no tratamento de micoses sistêmicas desde sua descoberta nos anos de 1950. O objetivo deste trabalho foi estabelecer o estado da arte das estratégias tecnológicas envolvidas nas formas de administração da AmB, nas intervenções diretas nos aspectos de melhoria de solubilidade do fármaco, que possibilitem sua administração por via intravenosa (iv) e minimizem sua toxicidade. Devido à limitada utilidade clínica do sal de desoxicolato (Fungizon®) em razão de sua alta toxicidade, sistemas de liberação mais eficientes foram desenvolvidos. Neste trabalho, são apresentadas as principais formulações disponíveis no mercado farmacêutico e outras formulações lipídicas promissoras, as quais se mostraram mais eficazes como veículos de solubilização e menos tóxicas quando comparadas com a AmB esoxicolato, mas ainda não fazem parte da rotina hospitalar para o tratamento de micoses profundas.

Incidence, Predictors, and Impact on Hospital Mortality of Amphotericin B Nephrotoxicity Defined Using Newer Acute Kidney Injury Diagnostic Criteria

Studies on amphotericin B (AmB) nephrotoxicity use diverse definitions of acute kidney injury (AKI). Here, we used the new Kidney Disease Improving Global Outcome (KDIGO) system to describe the incidence, predictors, and impact of AmB-induced AKI on hospital mortality in 162 patients treated with AmB (120 with deoxycholate preparation and 42 with liposomal preparation). KDIGO stage 1 requires an absolute increase of ≥0.3 mg/dl or ≥1.5× over baseline serum creatinine (SCr), while stage 2 requires ≥2×, and stage 3 requires ≥3×. A binary KDIGO definition (KDIGObin) corresponds to stage ≥1. For comparison, we included two definitions of AKI traditionally utilized in nephrotoxicity studies: ≥0.5 mg/dl (NT0.5) and ≥2× (NT2×) increase in baseline SCr. The overall incidence of AmB-induced AKI by KDIGObin was 58.6% (stage 1, 30.9%; stage 2, 18.5%; stage 3, 9.3%). Predictors of AKI by KDIGObin were older age and use of furosemide and angiotensin-converting enzyme inhibitor (ACE-I). Traditional criteria detected lower incidences of AKI, at 45.1% (NT0.5) and 27.8% (NT2×). Predictors of AKI by traditional criteria were older age and use of vancomycin (NT0.5) and use of vancomycin and vasopressors (NT2×). KDIGObin detected AKI 2 days earlier than the most sensitive traditional criterion. However, only traditional criteria were associated with intensive care unit (ICU) admission, mechanical ventilation, and mortality. In conclusion, the increase in sensitivity of KDIGObin is accompanied by a loss of specificity and ability to predict outcomes. Prospective studies are required to weigh the potential gain from early AKI detection against the potential loss from undue changes in management in patients with subtle elevations in SCr.

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.

Safety of a pre-formulated amphotericin B lipid emulsion for the treatment of Indian Kala-azar

Amphotericin B (AB) deoxycholate is highly effective in antimony refractory cases for the treatment of visceral leishmaniasis (VL) in Bihar. But the need for prolonged hospitalisation and frequent, occasionally serious, adverse events are its major drawbacks. Lipid formulations of AB are devoid of these problems, but very expensive. We evaluated the safety and efficacy of a commercial standardised amphotericin B emulsion, a product of AB formulated in lipid emulsion vehicle (ABLE) in the treatment of Indian VL. In this open label, non-comparative study, 15 patients in each group were given three daily intravenous infusions each of 3, 4 or 5 mg/kg. All 45 patients (15 in each group) completed the treatment. The drug was tolerated well. Infusion reactions occurred in 5 (11%) patients and vomiting in 2 (4.4%). No nephrotoxicity or other organ toxicity was observed. At the end of treatment all patients of every group were clinically and parasitologically cured. However, during 6 months follow up, three patients from the 5 mg/kg group and one from the 4 mg/kg group tested positive for splenic aspirate. Thus 41 (91.1%; 95% CI 78-97) of 45 patients were cured with a total dose ranging between 9 and 15 mg/kg. There was no dose response linear correlation. In this preliminary study, AB formulated in a lipid emulsion vehicle was safe and effective for the treatment of VL in India.

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.

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.

[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.

New investigational antifungal agents for treating invasive fungal infections

Systemic fungal infections have been recognised as a major cause of morbidity and mortality during the last two decades. There are only a few therapeutic options for these infections. Severe toxicity, such as impairment of renal function, limits the use of amphotericin B. Flucytosine is associated with side effects and drug resistance. Fluconazole and itraconazole are safer, though emergence of resistance and innate resistance in some fungal pathogens is a concern in their use. Therefore, there is a need for developing novel drugs and/or treatment strategies to combat these infections. In recent years, increased efforts by the pharmaceutical industry and academia have led to the discovery of new re-engineered or reconsidered antifungal agents that are more efficacious, safer and have a broad spectrum of activity. Lipid formulations of polyene antifungal agents, amphotericin B and nystatin, have the advantage of improved therapeutic index. Activity against resistant fungi, high bioavailability, safety and longer half-life are the properties that encourage development of the newer triazoles (e.g., voriconazole, ravuconazole and posaconazole). Echinocandin-like lipopeptide antibiotics are among the antifungal agents with a novel mode of action. In addition to these lead investigational compounds, development of newer antifungal agents is underway.