Voriconazole versus amphotericin B for invasive aspergillosis

Aspergillosis myocarditis in the immunocompromised host

Invasive cardiac aspergillosis has been rarely described in immunocompromised patients. This disease is difficult to diagnose by conventional laboratory, microbiologic, and imaging techniques, and is often recognized only post-mortem. The authors present the case of a 60-year-old woman admitted with an exacerbation of eosinophilic granulomatosis with polyangitiis (EGPA) who subsequently died from Aspergillus myocarditis, and compare the patient's case to prior literature. This serves as an up-to-date literature review on the topic of invasive cardiac aspergillosis.

Invasive pulmonary aspergillosis secondary to microwave ablation: a multicenter retrospective study

PURPOSE

Invasive pulmonary aspergillosis (IPA) is a life-threatening complication of microwave ablation (MWA) during the treatment of primary or metastatic lung tumors. The purpose of this study was to investigate the clinical, radiological and demographic characteristics and treatment responses of patients with IPA after MWA.

MATERIALS AND METHODS

From January 2011 to January 2016, all patients who were treated by MWA of their lung tumors from six health institutions were enrolled in this study. Patients with IPA secondary to MWA were identified and retrospectively evaluated for predisposing factors, clinical treatment, and outcome.

RESULTS

The incidence of IPA secondary to lung MWA was 1.44% (23/1596). Of the 23 patients who developed IPA, six died as a consequence, resulting in a high mortality rate of 26.1%. Using computed tomography (CT), pulmonary cavitation was the most common finding and occurred in 87.0% (20/23) of the patients. Sudden massive hemoptysis was responsible for one-third of the deaths (2/6). Most patients (22/23) received voriconazole as an initial treatment, and six patients with huge cavities underwent intracavitary lavage. Finally, 17 patients (73.9%) achieved treatment success.

CONCLUSIONS

Lung MWA may be an additional host risk factor for IPA, particularly in elderly patients with underlying diseases and in patients who have recently undergone chemotherapy. Early and accurate diagnosis of IPA after MWA is critical for patient prognosis. Voriconazole should be given as the first-line treatment as early as possible. Bronchial artery embolization or intracavitary lavage may be required in some patients.

Therapeutic drug monitoring in the treatment of invasive aspergillosis with voriconazole in cancer patients--an evidence-based approach

Invasive aspergillosis (IA) is a life-threatening complication in hematological cancer patients. Voriconazole (VCZ) is the established first-line treatment of IA. VCZ has a nonlinear pharmacokinetic profile and exhibits considerable variability of drug exposure. Therefore, therapeutic drug monitoring (TDM) of VCZ may help to improve treatment results in IA patients, but evidence-based data on the clinical use of TDM in patients treated with VCZ for IA are scarce. Evidence-based guidance is needed to support decisions on the use of TDM in routine VCZ therapy of IA. Our present analysis assessed published studies for evidence-based criteria for TDM of VCZ to improve efficacy and safety of IA therapy in cancer patients. Literature searches of MEDLINE and Cochrane database were performed. We identified 27 clinical studies reporting on the use of plasma level monitoring and/or TDM for VCZ. For each study, strength of recommendation and quality of evidence were categorized according to predefined criteria. A number of studies were published on plasma level monitoring (PLM) and TDM in VCZ therapy of IA. Across studies, VCZ levels >5-5.5 mg/L were found to be associated with toxicity, while reaching minimum levels of >1-2 mg/L appeared to improve efficacy. Timing, frequency, and intervention thresholds and dosage increments of VCZ for adjustment of plasma levels remain to be established. Currently, there is still no conclusive evidence for recommendations in routine clinical practice. More data from prospective randomized studies with TDM are desirable to provide a solid evidence basis for these approaches.

Current and future therapies for invasive aspergillosis

Invasive fungal infections have increase worldwide and represent a threat for immunocompromised patients including HIV-infected, recipients of solid organ and stem cell transplants, and patients receiving immunosuppressive therapies. High mortality rates and difficulties in early diagnosis characterize pulmonary fungal infections. Invasive pulmonary aspergillosis has been reviewed focussing on therapeutic management. Although new compounds have become available in the past years (i.e., amphotericin B lipid formulations, last-generation azoles, and echinocandines), new diagnostic tools and careful therapeutic management are mandatory to assure an early appropriate targeted treatment that represents the key factor for a successful conservative approach in respiratory fungal infections.

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.

Wait and see or rush and switch? New questions for the management of patients with febrile neutropenia receiving antifungal prophylaxis

Infections are a major threat for patients with haematological malignancies after intensive myelosuppressive chemotherapy. The severity and extent of neutropenia are considered a major risk factor for infections in these patients. Antibacterial treatment for patients with febrile neutropenia was standardised in the late 1990s with no further significant improvements within the last decade. Major progress in febrile neutropenia has come from the advent of new antifungals since the late 1990s. Lipid-based amphotericin B, third-generation azoles and the introduction of echinocandins allow a safer and effective treatment of invasive fungal infections. The mortality rate of invasive fungal infection is as high as 30-100% and a definitive diagnosis by culture may take too long. Thus, early diagnosis and early initiation of antifungal therapy remain important for the reduction of mortality rates. In the last two decades, randomised trials on prophylaxis and empirical therapy of invasive fungal infections were undertaken. Both primary prophylaxis and empirical therapy of invasive fungal infection proved effective. However, important questions remain unanswered. This article points out the clinicians view on unmet needs for patients with suspected invasive fungal infections after a decade of well-designed randomised trials for prevention of invasive fungal infections. Should we wait and see what happens in febrile neutropenic patients on antifungal prophylaxis or under empirical treatment or should we rush and switch antifungal treatment?

Liposomal amphotericin B: a review of its use as empirical therapy in febrile neutropenia and in the treatment of invasive fungal infections

Liposomal amphotericin B (AmBisome) is a lipid-associated formulation of the broad-spectrum polyene antifungal agent amphotericin B. It is active against clinically relevant yeasts and moulds, including Candida spp., Aspergillus spp. and filamentous moulds such as Zygomycetes, and is approved for the treatment of invasive fungal infections in many countries worldwide. It was developed to improve the tolerability profile of amphotericin B deoxycholate, which was for many decades considered the gold standard of antifungal treatment, despite being associated with infusion-related events and nephrotoxicity. In well controlled trials, liposomal amphotericin B had similar efficacy to amphotericin B deoxycholate and amphotericin B lipid complex as empirical therapy in adult and paediatric patients with febrile neutropenia. In addition, caspofungin was noninferior to liposomal amphotericin B as empirical therapy in adult patients with febrile neutropenia. For the treatment of confirmed invasive fungal infections, liposomal amphotericin B was more effective than amphotericin B deoxycholate treatment in patients with disseminated histoplasmosis and AIDS, and was noninferior to amphotericin B deoxycholate in patients with acute cryptococcal meningitis and AIDS. In adults, micafungin was shown to be noninferior to liposomal amphotericin B for the treatment of candidaemia and invasive candidiasis. Data from animal studies suggested that higher dosages of liposomal amphotericin B might improve efficacy; however, in the AmBiLoad trial in patients with invasive mould infection, there was no statistical difference in efficacy between the standard dosage of liposomal amphotericin B 3 mg/kg/day and a higher 10 mg/kg/day dosage, although the standard dosage was better tolerated. Despite being associated with fewer infusion-related adverse events and less nephrotoxicity than amphotericin B deoxycholate and amphotericin B lipid complex, liposomal amphotericin B use is still limited to some extent by these adverse events. Both echinocandins were better tolerated than liposomal amphotericin B. The cost of liposomal amphotericin B therapy may also restrict its use, but further pharmacoeconomic studies are required to fully define its cost effectiveness compared with other antifungal agents. Based on comparative data from well controlled trials, extensive clinical experience and its broad spectrum of activity, liposomal amphotericin B remains a first-line option for empirical therapy in patients with febrile neutropenia and in those with disseminated histoplasmosis, and is an option for the treatment of AIDS-associated cryptococcal meningitis, and for invasive Candida spp. or Aspergillus spp. infections. Amphotericin B, a macrocyclic, polyene antifungal agent, is thought to act by binding to ergosterol, the principal sterol in fungal cell membranes and Leishmania cells. This results in a change in membrane permeability, causing metabolic disturbance, leakage of small molecules and, as a consequence, cell death. In vitro and in vivo studies have shown that liposomal amphotericin B remains closely associated with the liposomes in the circulation, thereby reducing the potential for nephrotoxicity and infusion-related toxicity associated with conventional amphotericin B. Amphotericin B shows very good in vitro activity against a broad spectrum of clinically relevant fungal isolates, including most strains of Candida spp. and Aspergillus spp., and other filamentous fungi such as Zygomycetes. Liposomal amphotericin B has proven effective in various animal models of fungal infections, including those for candidiasis, aspergillosis, fusariosis and zygomycosis. Liposomal amphotericin B also shows immunomodulatory effects, although the mechanisms involved are not fully understood, and differ from those of amphotericin B deoxycholate and amphotericin B colloidal dispersion. In adult patients with febrile neutropenia, intravenous liposomal amphotericin B has nonlinear pharmacokinetics, with higher than dose-proportional increases in exposure being consistent with reticuloendothelial saturation and redistribution of amphotericin B in the plasma compartment. Liposomal amphotericin B is rapidly and extensively distributed after single and multiple doses, with steady-state concentrations of amphotericin B attained within 4 days and no clinically relevant accumulation of the drug following multiple doses of 1-7.5 mg/kg/day. In autopsy tissue, the highest concentrations of the drug were found in the liver and spleen, followed by the kidney, lung, myocardium and brain tissue. Elimination of liposomal amphotericin B, like that of amphotericin B deoxycholate, is poorly understood; its route of metabolism is not known and its excretion has not been studied. The terminal elimination half-life is about 7 hours. No dosage adjustment is required based on age or renal impairment. In several randomized, double-blind trials (n = 73-1095) in adult and/or paediatric patients, liposomal amphotericin B was effective as empirical therapy or as treatment for confirmed invasive fungal infections, including invasive candidiasis, candidaemia, invasive mould infection (mainly aspergillosis), histoplasmosis and cryptococcal meningitis. All agents were administered as an intravenous infusion; the typical dosage for liposomal amphotericin B was 3 mg/kg/day. Treatment was generally given for 1-2 weeks. Participants in trials evaluating empirical therapy had neutropenia and a persistent fever despite antibacterial treatment and had received chemotherapy or undergone haematopoietic stem cell transplantation. As empirical therapy in adult and paediatric patients, liposomal amphotericin B appeared to be as effective as amphotericin B deoxycholate (approximately 50% of patients in each group achieved treatment success) or amphotericin B lipid complex (approximately 40% of liposomal amphotericin B recipients experienced treatment success). Of note, in the first trial, results of the statistical test to determine equivalence between treatments were not reported. In the second trial, efficacy was assessed as an 'other' endpoint. In another trial, caspofungin was shown to be noninferior to liposomal amphotericin B, with approximately one-third of patients in each group experiencing treatment success. Liposomal amphotericin B was significantly more effective than amphotericin B deoxycholate for the treatment of moderate to severe disseminated histoplasmosis in patients with AIDS, with 88% and 64% of patients, respectively, having a successful response. Liposomal amphotericin B was noninferior to amphotericin B deoxycholate for the treatment of cryptococcal meningitis in terms of mycological success. Micafungin therapy was shown to be noninferior to liposomal amphotericin B for the treatment of adult patients with candidaemia or invasive candidiasis. In a substudy in paediatric patients, which was not powered to determine noninferiority, liposomal amphotericin B was as effective as micafungin for the treatment of candidaemia or invasive candidiasis. In this patient population, within each trial, 90% of adult patients and approximately three-quarters of paediatric patients in both treatment groups experienced a successful response. In patients with invasive mould infection (mainly aspergillosis), there was no difference in efficacy between a higher dosage of liposomal amphotericin B (10 mg/kg/day) and the standard dosage (3 mg/kg/day), with 46% and 50% of patients experiencing a favourable overall response. In well designed clinical trials, liposomal amphotericin B was generally at least as well tolerated as other lipid-associated formulations of amphotericin B and better tolerated than amphotericin B deoxycholate in adult and paediatric patients. Compared with other amphotericin B formulations, liposomal amphotericin B treatment was associated with a lower incidence of infusion-related adverse events and nephrotoxicity. A higher than recommended dosage of liposomal amphotericin B (10 mg/kg/day) was associated with an increased incidence of nephrotoxicity compared with the standard dosage (3 mg/kg/day), although the incidence of infusion-related reactions did not differ between treatment groups. In general, liposomal amphotericin B treatment was not as well tolerated as echinocandin therapy in well designed clinical trials. As empirical therapy or for the treatment of confirmed invasive fungal infections in adult patients, liposomal amphotericin B recipients experienced more infusion-related events and nephrotoxicity than caspofungin or micafungin recipients. There was no difference in the incidence of these adverse events between the liposomal amphotericin B and micafungin groups in a study in paediatric patients.

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.

Invasive aspergillosis: current and future challenges in diagnosis and therapy

Invasive aspergillosis is an increasingly common disease. While there have been significant advances in the past decade, significant challenges remain in terms of diagnosis and therapy. Some of the recent advances are outlined and future opportunities to improve the unacceptable mortality that is currently associated with this infection are considered.

Efficacy and toxicity of caspofungin in combination with liposomal amphotericin B as primary or salvage treatment of invasive aspergillosis in patients with hematologic malignancies

BACKGROUND

Caspofungin (CAS) as salvage therapy for refractory invasive aspergillosis (IA) had a response rate of 45% among a heterogeneous group of patients. The use of CAS with other agents is appealing given its unique mechanism of action. Therefore, the authors retrospectively evaluated the efficacy and toxicity of CAS plus liposomal amphotericin B (LipoAMB) in patients with documented (definite or probable) or possible IA.

METHODS

Patients were evaluable for outcome if they received CAS/LipoAMB for at least 7 days. Patients who received CAS and LipoAMB sequentially were excluded. All patients were evaluable for toxicity. Outcome was assessed weekly and at the end of therapy. Stable disease and progression were considered treatment failures.

RESULTS

Forty-eight patients with documented (n=23) or possible (n=25) IA were identified between March 2001 and December 2001. The majority of the patients (65%) received CAS/LipoAMB as salvage therapy for progressive IA despite 7 or more days of previous LipoAMB monotherapy. The overall response rate was 42%. No significant toxic effects were seen. Factors associated with failure at the end of therapy were documented IA (P=0.03), significant steroid use before the study (P=0.02), and duration of combination therapy for less than 14 days (P=0.01). The response rate in patients with progressive documented IA was low (18%).

CONCLUSIONS

The CAS/LipoAMB combination is a promising preemptive therapy for IA and was generally well tolerated. This combination might have limited benefit as salvage therapy for documented IA.