One-year follow-up of very preterm infants who received lucinactant for prevention of respiratory distress syndrome: results from 2 multicenter randomized, controlled trials

BACKGROUND

The benefits of exogenous surfactants for prevention or treatment of respiratory distress syndrome are well established, but there is a paucity of long-term follow-up data from surfactant-comparison trials.

OBJECTIVE

We sought to determine and compare survival and pulmonary and neurodevelopmental outcomes through 1 year corrected age of preterm infants who received lucinactant and other surfactants in the SELECT (Safety and Effectiveness of Lucinactant Versus Exosurf in a Clinical Trial) and STAR (Surfaxin Therapy Against Respiratory Distress Syndrome) trials individually and, secondarily, from analysis using combined data from these 2 trials.

METHODS

All infants from both trials who were randomly assigned to administration of lucinactant (175 mg/kg), colfosceril palmitate (67.5 mg/kg), beractant (100 mg/kg), or poractant alfa (175 mg/kg) were prospectively followed through 1 year corrected age, at which point masked assessment of outcomes was performed for surviving infants. One-year survival was a key outcome of interest. Other parameters assessed included rates of rehospitalization and respiratory morbidity and gross neurologic status. Data were analyzed by comparing the different surfactants within each trial and, in secondary analysis, combining data from both trials to compare lucinactant versus the animal-derived surfactants (beractant and poractant) used in these trials. Survival rates over time were compared by using the Wilcoxon test for survival through 1 year corrected age and logistic regression for comparison of fixed time points. The latter analyses were performed by using the prespecified approach, where loss to follow-up or withdrawal of consent was imputed as a death, and also using raw data. Other outcomes were analyzed by using the Cochran-Mantel-Haenszel test or logistic regression for categorical data, and analysis of variance on ranks was used for continuous data.

RESULTS

Very few cases were lost to follow-up in either trial (29 of 1546 enrolled in both trials [1.9%]). In the primary analysis of the SELECT trial comparing lucinactant to either colfosceril or beractant, there were no significant differences in the proportion of infants who were alive through 1 year corrected age. Fixed-time-point estimates of mortality at 1 year corrected age imputing loss to follow-up as a death were 28.1% for lucinactant, 31.0% for colfosceril, and 31.0% for beractant. By using raw data without imputing loss to follow-up as a death, mortality estimates at 1 year corrected age were computed to be 26.6%, 29.1%, and 28.3%, respectively. In the primary analysis of the STAR trial, significantly more infants treated with lucinactant were alive through 1 year corrected age compared with those who received poractant alfa. Fixed time estimates of mortality at 1 year corrected age imputing loss to follow-up as a death were 19.4% for lucinactant and 24.2% for poractant. These estimates using raw data that did not impute loss to follow-up as a death were 18.6% and 21.9%, respectively. In the combined analysis, survival through 1 year corrected age was higher for infants in the lucinactant group versus that of the infants in the animal-derived surfactants (beractant and poractant) group. The fixed-time-point estimates of mortality at 1 year corrected age imputing loss to follow-up as a death for lucinactant and animal-derived surfactants were 26.0% and 29.4%, respectively. However, the 1-year-corrected-age estimates using combined raw data were 24.6% for the lucinactant group and 26.7% for the animal-derived surfactant group. The incidence of postdischarge rehospitalizations, total number of rehospitalizations, incidence of respiratory illnesses, and total number of respiratory illnesses were generally similar among those in the treatment groups. Neurologic status at 1 year corrected age was essentially similar between infants who received lucinactant and those who received all other surfactants used in these 2 trials.

CONCLUSIONS

Findings from this 1-year follow-up of both lucinactant trials indicate that this new peptide-based synthetic surfactant is at least as good, if not superior, to animal-derived surfactants for prevention of respiratory distress syndrome and may be a viable alternative to animal-derived products.

Amphotericin B–Associated Hyperbilirubinemia: Case Report and Review of the Literature

A 53-year-old woman with an intraabdominal infection secondary to Candida albicans experienced hyperbilirubinemia after receiving amphotericin B in two different formulations--amphotericin B deoxycholate and amphotericin B lipid complex. Only a few case reports of amphotericin B-induced hyperbilirubinemia have been documented in the literature, each with different patterns of corresponding abnormalities in liver function tests. The unpredictable nature of this adverse effect warrants monitoring of bilirubin levels and liver function at baseline and potentially during therapy with amphotericin B, regardless of formulation, dosage, or duration of therapy.

What is the current and future status of conventional amphotericin B?

Amphotericin B deoxycholate has been the 'gold standard' treatment for invasive fungal infections for over 40 years. Driven to improve on the renal toxicity of amphotericin B deoxycholate, extensive pharmaceutical research has led to the development of several new antifungals including lipid formulations of amphotericin B, broad-spectrum azoles and echinocandins. Compared with amphotericin B deoxycholate, the lipid formulations of amphotericin B (amphotericin B lipid complex, amphotericin B colloidal dispersion and liposomal amphotericin B) share distinct advantages in improved drug safety, in particular reduced incidence and severity of amphotericin B deoxycholate-related nephrotoxicity. However, the lipid formulations of amphotericin B are significantly more expensive than amphotericin B deoxycholate and, as for many of these new antifungals, there are as yet insufficient published studies to guide clinicians. This paper examines aspects of safety, efficacy, and health economic data for the lipid formulations of amphotericin B in particular, in order to provide a rationale to justify substituting amphotericin B deoxycholate with the lipid formulations of amphotericin B.

Antifungal combination treatment: a future perspective

The use of antifungal combination therapy is a new clinical approach for combating fungal infections. Although few conclusive clinical studies have been performed to date, data exist that strongly suggest that combination therapy would benefit specific patient subgroups (e.g. stem-cell transplant recipients). This paper examines the evidence available from in vitro, experimental, and clinical studies, and seeks to discover viable clinical strategies for this promising new therapeutic approach.

Non-comparative evaluation of the safety of aerosolized amphotericin B lipid complex in patients undergoing allogeneic hematopoietic stem cell transplantation

Allogeneic hematopoietic stem cell transplant (HSCT) recipients are at increased risk for invasive fungal infections (IFIs) over prolonged periods of time. Aerosolized amphotericin B lipid complex (ABLC) has shown promise in lung transplant recipients as a convenient means of delivering protective drug to the upper airways avoiding systemic toxicities. The safety and tolerability of aerosolized ABLC in 40 subjects undergoing allogeneic HSCT was prospectively investigated in an open-labeled, non-comparative study. Subjects received aerosolized ABLC treatment once daily for 4 days, then once weekly for 13 weeks; fluconazole was administered daily as standard of care through post-transplant day 100. Pulmonary mechanics were measured before and after each dose of inhaled ABLC; adverse events (AEs) and the development of IFI were also monitored. Cough, nausea, taste disturbance, or vomiting followed 2.2% of 458 total inhaled ABLC administrations; 5.2% of inhaled ABLC administrations were associated with >or=20% decrease in pulmonary function measurements (forced expiratory volume in 1 second or forced vital capacity) and none required treatment with bronchodilators or withdrawal from study. Four mild AEs were considered possibly or probably related to study treatment; no deaths or withdrawals from treatment were attributed to study drug. Of 3 proven IFIs occurring during the study period, only 1, a catheter-related case of disseminated fusariosis, occurred while the subject was receiving study medication. Aerosolized ABLC was well tolerated in allogeneic HSCT recipients. With only 1 of 40 subjects developing IFI while receiving treatment, the combination of fluconazole and inhaled ABLC warrants further study as antifungal prophylaxis following allogeneic HSCT.

Study of renal safety in amphotericin B lipid complex-treated patients

To investigate the renal safety of amphotericin B lipid complex (ABLC), records from 3514 ABLC-treated patients with fungal infections were reviewed. The median change in predicted creatinine clearance (CCr) from baseline to the end of therapy was -3 mL/min (range, -119 to 118 mL/min); doubling of serum creatinine (S-Cr) level occurred in 13% of patients, and new dialysis was needed for 3% of patients. Patients with underlying renal disease who had received prior antifungal therapy demonstrated a median CCr of 0.5 mL/min (range, -107 to 52 mL/min). Despite increased risk for renal impairment in allogeneic hematopoietic stem-cell transplant recipients, only 17% of patients demonstrated end-of-therapy doubling of S-Cr levels, and the median change in CCr was -10 mL/min (range, -107 to 108 mL/min). In ABLC-treated patients, concomitant treatment with potentially nephrotoxic agents and a baseline S-Cr level of <2 mg/dL were factors predisposing for the development of nephrotoxicity. These data provide evidence that ABLC may be used safely to treat patients who are at increased risk for renal impairment.

Effectiveness of amphotericin B lipid complex (ABLC) treatment in allogeneic hematopoietic cell transplant (HCT) recipients with invasive aspergillosis (IA)

A total of 85 allogeneic hematopoietic cell transplant (HCT) recipients with invasive aspergillosis treated with amphotericin B lipid complex (ABLC) were identified from the Collaborative Exchange of Antifungal Research (CLEAR) database. Of these patients, 78% (66/85) presented with pulmonary aspergillosis. Graft-versus-host disease (GVHD) was present in 24 of 85 patients. The response rate to ABLC was 31% (26/85) overall and 21% (5/24) in patients with GVHD. The overall response rate to first-line ABLC treatment was 41% (11/27). Four of nine (44%) patients with GVHD responded to first-line treatment with ABLC, while only one of 13 (8%) responded to ABLC as second-line therapy. Five of 18 (28%) and four of 14 (29%) patients, respectively, responded to sequential or concurrent treatment with ABLC and itraconazole. None of seven patients responded who continued receiving itraconazole after the start of ABLC therapy. At the end of ABLC therapy, serum creatinine had doubled in 12% of patients (10/85), and 2% (2/85) had developed a requirement for dialysis. These data suggest that ABLC, especially when administered as first-line therapy, can result in clinical response even in the most immunocompromised patients, that is, HCT recipients with GVHD, with minimal effects on renal function.

The hepatotoxicity of antifungal medications in bone marrow transplant recipients

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Treatment of Non-Aspergillus Moulds in Immunocompromised Patients, with Amphotericin B Lipid Complex

An assessment was made of the efficacy and renal safety of amphotericin B lipid complex (ABLC) in the treatment of patients with invasive fungal infections caused by moulds other than Aspergillus species, on the basis of a retrospective analysis of data from the Collaborative Exchange of Antifungal Research (CLEAR) database. Data from CLEAR for 64 patients with zygomycosis were published previously. The database was further queried and yielded results for 28 patients with fusariosis and 84 patients infected with other non-Aspergillus moulds. Of 26 patients with fusariosis whose results could be evaluated, 46% (n = 12) were cured or improved, and an additional 12% (n = 3) were stable. Of 79 patients infected with other non-Aspergillus moulds whose results could be evaluated, 61% (n = 48) were cured or improved, and an additional 15% (n = 12) were stable. In an area with little guidance for therapy, the CLEAR data indicate that ABLC can be an effective broad-spectrum treatment choice for several invasive and refractory non-Aspergillus mould infections.

Efficacy and safety of amphotericin B lipid complex in 548 children and adolescents with invasive fungal infections

BACKGROUND

The safety and efficacy of amphotericin B lipid complex injection (ABELCET; Enzon Pharmaceuticals, Piscataway, NJ) was assessed in 548 children and adolescents 0-20 years of age who were enrolled in the Collaborative Exchange of Antifungal Research (CLEAR) registry. To our knowledge, this is the largest series of pediatric patients treated for invasive mycoses with a single agent. All patients had cancer or had received a bone marrow, cord blood or solid organ transplant and were treated with amphotericin B lipid complex for documented or suspected fungal infection.

METHODS

The CLEAR database was queried for all patients 0-20 years of age from 1996 to 2000. Data gathered included demographic variables, underlying disease type, reasons for the use of amphotericin B lipid complex injection, dosing information, clinical response and renal effects.

RESULTS

Most patients were either intolerant of or refractory to conventional antifungal therapy, and almost one-half were neutropenic at treatment onset. Of the 548 patients, 300 (54.7%) were transplant recipients and 393 (71.7%) had received one or more concomitant nephrotoxins. Candida and Aspergillus were the most commonly isolated species in patients with proven or probable infections. Response data were evaluable for 255 of the 285 patients with documented single or multiple pathogens. A complete (cured) or partial (improved) response was achieved in 54.9% of patients, with an additional 16.9% of patients having a stable outcome. Among patients with proven Aspergillus infection, the response rates (cured + improved) were 40.5 and 37.5% in transplant and nontransplant patients, respectively. When stable responses were added, the response rates were 48.6 and 71.9%, respectively. There were few clinically significant deleterious effects on renal function. There was no significant difference between the rates of new hemodialysis versus baseline hemodialysis. Elevations in serum creatinine of >1.5 x baseline and >2.5 x baseline values were seen in 24.8 and 8.8% of all patients, respectively.

CONCLUSIONS

The safety and efficacy data from this large pediatric population support the use of amphotericin B lipid complex injection for treatment of invasive fungal infections in immunocompromised children and adolescents, including the high risk subgroup of transplant recipients. The overall response rate and safety profile in pediatric patients who were largely intolerant of or refractory to conventional antifungal therapy were consistent with earlier reported findings of smaller trials.

Fatal fat embolism following amphotericin B lipid complex injection

A case of amphotericin B lipid complex induced fatal fat embolism is described. A 41-year-old Caucasian man with AIDS was undergoing treatment for cryptococcal meningitis with amphotericin B. His course was complicated by renal failure necessitating a change in therapy to amphotericin B lipid complex (Abelcet). At approximately 48 h, the patient developed tachycardia, tachypnea, respiratory failure, decline in hematocrit, thrombocytopenia, and alteration in mental status. Autopsy findings included fat emboli involving heart, lungs, kidney, and brain. To our knowledge, this is the first case report of a fatal fat embolism caused by intravenous liposome drug delivery.

Lipid-based amphotericin in pulmonary zygomycosis: safety and efficacy of high exposure in a renal allograft recipient

Zygomycosis is associated with a high mortality in immunosuppressed patients. Treatment typically includes surgical resection and administration of intravenous amphotericin B. Success of treatment may require withdrawal of immunosuppression, with risk of graft loss. We report the successful treatment of invasive pulmonary zygomycosis, following initial surgical resection, using very high doses of lipid-based amphotericin B without withdrawal of immunosuppression. The patient received daily doses up to 10 mg/kg/day (51 g cumulatively) of lipid-based amphotericin B along with a brief course of intrapleural amphotericin. Despite immunosuppression not being withdrawn, the patient's kidney allograft function remained stable. We conclude that high doses of lipid-based amphotericin B can be safe and effective as part of the treatment regimen for pulmonary zygomycosis.

Assessment of nephrotoxicity in patients receiving amphotericin B lipid complex: a pharmacosurveillance study in Spain

This study assessed the risk of haematological, renal and hepatic toxicity associated with amphotericin B lipid complex (ABLC; Abelcet) in a multicentre, open-label, non-comparative study of 93 patients from 17 different hospitals who received ABLC because of proven or suspected systemic fungal infection or leishmaniasis. Most (66%) patients had onco-haematological diseases. Optimum treatment with ABLC comprised a slow (2-h) infusion dose of 5 mg/kg/day for a minimum period of 14 days. Biochemical and haematological parameters were measured pre-, during and post-treatment. In the overall patient group, the mean serum creatinine concentration was similar pre- and post-study (1.00 +/- 1.14 mg/dL vs. 1.20 +/- 1.19 mg/dL; p > 0.05). There were no significant changes pre- and post-treatment in concentrations of haemoglobin, potassium, transaminases and bilirubin. There was no significant correlation between the dose administered and the concentrations of serum creatinine (Spearmann 0.22). There was no greater nephrotoxicity in the patients with previous renal failure, or in those who had received amphotericin B previously. There were serious adverse events in five patients, but other alternative causes that could explain these events were present in three of these patients. Fevers or chills were experienced by 23% of the patients during the ABLC infusion, but only in one case did this necessitate the suspension of treatment. It was concluded that ABLC is a drug with low nephrotoxicity, even when administered to patients with pre-existing renal insufficiency. Adverse events were generally slight or moderate, and were managed easily with appropriate pre-medication.

Low-dose amphotericin B lipid complex vs. conventional amphotericin B for empirical antifungal therapy of neutropenic fever in patients with hematologic malignancies--a randomized, controlled trial

BACKGROUND

Conventional amphotericin B (c-AmB) remains the empirical antifungal treatment of choice for neutropenic patients with persistent fever of unknown origin (FUO). Unfortunately, empirical treatment with c-AmB is hampered by its safety profile, with frequent infusion-related adverse events (IRAEs) and renal toxicity. Amphotericin B lipid complex (ABLC) has been investigated for this indication due to its low toxicity profile. The recommended dose of ABLC is 5 mg/kg/d, which is five to seven times higher than the recommended dose of c-AmB.

METHODS

This randomized, controlled trial includes 105 adult patients with hematologic malignancies and with FUO after receiving chemotherapy or autologous stem cell transplantation. Patients were randomly allocated to receive ABLC at 1 mg/kg/d or c-AmB at 0.6 mg/kg/d for empirical antifungal therapy.

RESULTS

The incidence of renal toxicity was significantly lower in the ABLC group, compared with c-AmB group: 8% vs. 32%, respectively (P = 0.003). The rates of IRAEs were similar in both groups (73% for ABLC vs. 77% for c-AmB). The overall response rate was 72% for ABLC compared with 48% for c-AmB (P = 0.018). This difference was mainly due to the significantly higher renal toxicity in the c-AmB group. The number of emergent fungal infections and overall mortality were similar in both groups.

CONCLUSIONS

This randomized trial suggests that ABLC at 1 mg/kg/d produces less nephrotoxicity than c-AmB, without differences in the incidence of IRAEs and with similar efficacy.

Efficacy, safety and cost-effectiveness of Amphotericin B Lipid Complex (ABLC): a review of the literature

Amphotericin B Lipid Complex (ABLC) was the first lipid-based formulation of amphotericin B (AmB) to be developed, it was designed to provide a less toxic alternative to conventional AmB without compromising efficacy. Preclinical and early clinical data relating to ABLC have been presented in previous reviews. This paper reviews more recent published data on the efficacy, safety and cost-effectiveness of ABLC. All published manuscripts and conference abstracts were searched on MEDLINE, BIOL and SCIN for the period between January 1997 and August 2003. Comparative and non-comparative studies of ABLC are usually mild or moderate and are manageable were considered. Comparative studies and additional data from non-comparative studies suggest that ABLC 5 mg/kg/day is safe and effective for the treatment of documented or suspected systemic fungal infections in adults and children who are refractory to or intolerant of conventional AmB. ABLC is effective against a wide range of pathogens and efficacy is at least as good as conventional AmB or the other lipid-based formulations. The safety profile of ABLC is improved compared with conventional AmB; ABLC is less nephrotoxic than conventional AmB and can be given safely to patients with pre-existing renal impairment. The most commonly reported adverse effects are transient infusion-related events, including chills, fever, nausea and vomiting, which with premedication. Comparative studies suggest that ABLC is a cost-effective treatment option compared with conventional AmB or other lipid-based formulations of amphotericin B.

Amphotericin B Treatment for Indian Visceral Leishmaniasis: Conventional versus Lipid Formulations

In Bihar, India, where visceral leishmaniasis is hyperendemic, amphotericin B deoxycholate is now first-line parenteral treatment. To test the efficacy of amphotericin B deoxycholate versus that of its lipid formulations, Indian patients were randomized to receive treatment with amphotericin B deoxycholate (1 mg/kg on alternate days for 30 days; n=51), liposomal amphotericin B (2 mg/kg per day for 5 days; n=51), or amphotericin B lipid complex (2 mg/kg per day for 5 days; n=51). Infusion-associated reactions were frequent and persistent in subjects treated with amphotericin B deoxycholate. The illness of 3 patients failed to respond to treatment, and 5 patients experienced relapse. Final cure rates were similar. Estimated total treatment costs for a 25-kg patient-417 dollars for amphotericin B deoxycholate, 872 dollars for liposomal amphotericin B, and 947 dollars for amphotericin B lipid complex-differed as a result of drug cost. Substantial reductions (approximately 60%) in the price of liposomal amphotericin B and amphotericin B lipid complex would make treatment costs comparable to that of amphotericin B deoxycholate, permitting administration of short-course regimens in India.

Amphotericin B lipid complex versus no treatment in the secondary prophylaxis of visceral leishmaniasis in HIV-infected patients

OBJECTIVES

Visceral leishmaniasis (VL) in HIV-positive patients is characterized by a chronic course with frequent relapse. The aim of this study was to evaluate the efficacy and safety of amphotericin B lipid complex (ABLC) in preventing VL relapses in HIV-infected patients.

METHODS

This was a multicentre, open-label (with blinded centralized randomization), parallel, no-treatment, controlled clinical trial. HIV-infected patients, with at least one previous treated episode of VL and with negative bone marrow aspirate for Leishmania parasites prior to the study, were randomized to receive either ABLC 3 mg/kg/day every 21 days (ABLC) or no treatment (NT). Patients were followed-up every 9 weeks for up to 12 months, and the efficacy was measured as the proportion of patients remaining free (non-relapse) of VL at 1 year of follow-up. The primary analysis was performed on an intention-to-treat basis.

RESULTS

One hundred and fifteen patients were screened, but only 17 were randomized: eight in the ABLC group and nine in the NT group. The intention-to-treat analysis of data showed 50% of patients remaining free of VL at 12 months of follow-up (95% CI = 15.7%, 84.3%) in the ABLC group, and 22.2% (95% CI = 2.8%, 60.0%) in the NT group. The non-relapse odds ratio was 3.5 (95% CI = 0.30%, 52.0%) favouring ABLC. ABLC was well tolerated: patients only presented infusion-related mild adverse events. No patients from either group discontinued treatment or died during follow-up.

CONCLUSIONS

ABLC, administered every 21 days for 12 months, is useful as secondary prophylaxis in preventing VL relapse in HIV-infected patients, and is well tolerated.

Comparative safety of amphotericin B lipid complex and amphotericin B deoxycholate as aerosolized antifungal prophylaxis in lung-transplant recipients

BACKGROUND

Aerosolized administrations of amphotericin B deoxycholate (AmBd) and amphotericin B lipid complex (ABLC) in lung transplant recipients were compared for safety and tolerability. The incidence of invasive fungal infections in patients receiving aerosolized amphotericin B formulations as sole prophylaxis was determined.

METHODS

A prospective, randomized (1:1), double-blinded trial was conducted with 100 subjects. AmBd and ABLC were administered postoperatively by nebulizer at doses of 25 mg and 50 mg, respectively, which were doubled in mechanically ventilated patients. The planned treatment was once every day for 4 days, then once per week for 7 weeks. Treatment-related adverse events and invasive fungal infections were quantitated for 2 months after study drug initiation.

RESULTS

Intent-to-treat analysis revealed study drug was discontinued for intolerance in 6 of 49 (12.2%) and 3 of 51 (5.9%) patients in the AmBd- and ABLC-treated groups, respectively (p=0.313). Subjects receiving AmBd were more likely to have experienced an adverse event (odds ratio 2.16, 95% confidence interval 1.10, 4.24, p=0.02). Primary prophylaxis failure within 2 months of study drug initiation was observed in 7 of 49 (14.3%) AmBd-treated patients and 6 of 51 (11.8%) ABLC-treated patients. No fungal pneumonias were observed. Only two (2%) patients experienced documented primary prophylaxis failure with Aspergillus infections within the follow-up period.

CONCLUSIONS

Both aerosol AmBd and ABLC appear to be associated with a low rate of invasive pulmonary fungal infection in the early posttransplant period. Patients receiving ABLC were less likely to experience a treatment-related adverse event.

Reversible dilated cardiomyopathy related to amphotericin B therapy

We describe a patient who developed dilated cardiomyopathy and clinical congestive heart failure after 2 months of therapy with amphotericin B (AmB) for disseminated coccidioidomycosis. His echocardiographic abnormalities and heart failure resolved after posaconazole was substituted for AmB. It is important to recognize the rare and potentially reversible toxicity of AmB.

Amphotericin B lipid complex versus meglumine antimoniate in the treatment of visceral leishmaniasis in patients infected with HIV: a randomized pilot study

Optimal treatment for HIV-related visceral leishmaniasis (VL) has still to be established. A pilot clinical trial was carried out in 57 HIV-VL coinfected patients to compare the efficacy and safety of amphotericin B lipid complex (ABLC) versus meglumine antimoniate. The patients were randomized to receive either ABLC 3 mg/kg/day for 5 days (ABLC-5, 18 patients), ABLC 3 mg/kg/day for 10 days (ABLC-10, 20 patients) or meglumine antimoniate 20 mg Sbv /kg/day for 28 days (19 patients). Treatment was considered successful if parasites were not detected in a bone marrow aspirate after treatment. Parasitological cure was attained in 33% (95% CI: 13%-59%) of the ABLC-5 group, in 42% (95% CI: 16%-62%) of the ABLC-10 group and in 37% (95% CI: 16%-62%) of the meglumine antimoniate group (P = 0.94). Eight out of 19 patients administered antimoniate discontinued treatment prematurely following serious adverse events, compared with one in the ABLC groups (P = 0.0006). The efficacy of ABLC is similar to meglumine antimoniate, but the severity of toxicity in the treatment of HIV-VL is lower with ABLC.

Inhaled synthetic surfactant abolishes the early allergen-induced response in asthma

Allergen-induced inhibition of pulmonary surfactant in asthma may promote airway oedema and consequently potentiate the severity of the asthmatic response. A randomised, single-blind, cross-over study of an inhaled synthetic phospholipid dry-powder surfactant (Pumactant) was conducted in atopic, asthmatic subjects with previously documented early and late asthmatic responses (EAR and LAR) to an inhaled allergen. This was conducted to evaluate the role of exogenous surfactant administration on EAR and LAR. A total of seven subjects had complete evaluable data and received the full dose of Pumactant. Asthmatic subjects inhaled two separate doses of 400 mg Pumactant prior to an allergen exposure. The first dose was administered 8 h in advance and the second dose 30 min in advance. The dosage occurred through a purpose-built administration device. This was followed by a standard bronchial-provocation test, and forced expiratory volume in one second (FEV1) was measured at regular intervals over a 10-h period. Pumactant was well tolerated and, surprisingly, abolished the EAR but not the LAR in all seven subjects. The mean area under the curve between 0-2 h (EAR) following bronchial provocation test was 0.08 for the Pumactant treatment group (PT) and 13.29 for the no treatment (NT) group. The maximum drop in FEV1 for EAR was 4.19% and 23.98% in the PT and the NT group, respectively. The demonstration of inhibition of the early asthmatic response by exogenous surfactant, provides the first evidence that pulmonary surfactant dysfunction may also contribute to the very early asthmatic response to allergen. Exogenous surfactant administration could serve as a useful adjunct in controlling the early allergen-induced symptoms in patients with allergic asthma.

Triad of acute infusion-related reactions associated with liposomal amphotericin B: analysis of clinical and epidemiological characteristics

We investigated the clinical characteristics and treatment of patients with a distinctive triad of acute infusion-related reactions (AIRRs) to liposomal amphotericin B (L-AMB) via single-center and multicenter analyses. AIRRs occurred alone or in combination within 1 of 3 symptom complexes: (1) chest pain, dyspnea, and hypoxia; (2) severe abdomen, flank, or leg pain; and (3) flushing and urticaria. The frequency of AIRRs in the single-center analysis increased over time. Most AIRRs (86%) occurred within the first 5 min of infusion. All patients experienced rapid resolution of symptoms after intravenous diphenhydramine was administered. The multicenter analysis demonstrated a mean overall frequency of 20% (range, 0%-100%) of AIRRs among 64 centers. A triad of severe AIRRs to L-AMB may occur in some centers; most of these reactions may be effectively managed by diphenhydramine administration and interruption of L-AMB infusion.

Severe hyperphosphatemia resulting from high-dose liposomal amphotericin in a child with leukemia

Children with acute lymphoblastic leukemia (ALL) are at risk for serious electrolyte abnormalities. The authors report their experience in managing a child with ALL who developed severe hyperphosphatemia as a consequence of a large exogenous load of phosphorus from high-dose liposomal amphotericin B. Health care providers need to recognize this potentially life-threatening complication of liposomal amphotericin B, since early detection and intervention can prevent significant morbidity.

Liposomal amphotericin B in the treatment of visceral leishmaniasis in immunocompetent patients

The leishmaniases are protozoan diseases caused by Leishmania parasites. The first-line treatment of its visceral forms is pentavalent antimony (meglumine antimoniate or sodium stibogluconate), but toxicity is frequent with this drug. Moreover antimony unresponsiveness is increasing in Leishmania infantum and L. donovani foci, both in immunocompetent and in immunosuppressed patients. Amphotericin B is a polyene macrolide antibiotic that binds to sterols in cell membranes. It is the most active antileishmanial agent in use. Its infusion-related and renal toxicity may be reduced by lipid-based delivery. Liposomal amphotericin B (AmBisome); Gilead Science, Paris, France) seems to be less toxic than other amphotericin B lipid formulations (Amphocil); Liposome Technology Inc., Menlo Park, CA, USA, Amphotec); Ben Venue Laboratories Inc., Bedford, OH, USA). Optimal drug regimens of AmBisome) vary from one geographical area to another. In the Mediterranean Basin, a total dose of 18 mg/kg (3 mg/kg on days 1-5 and 3 mg/kg on day 10) could be used as first-line treatment of visceral leishmaniasis in immunocompetent patients. In immunocompromised patients, especially those co-infected with HIV, relapses are frequent with AmBisome), as with other drugs.

Infrequent occurrence of amphotericin B lipid complex-associated nephrotoxicity in various clinical settings at a university hospital: a retrospective study

BACKGROUND

Lipid-based formulations of amphotericin B (AMB) have been shown to significantly lessen the occurrence of nephrotoxicity associated with the conventional form of AMB. A MEDLINE search of literature published from 1983 to 2002, using the search terms amphotericin B and nephrotoxicity, identified only 1 large, randomized, prospective trial that has tried to compare the nephrotoxicity rates among lipid-based AMB formulations. Using the nephrotoxicity surrogate marker of doubling of serum creatinine (SCr) level, the investigators reported a high rate of AMB lipid complex (ABLC)-associated nephrotoxicity (42.3%). However, enrollment in that study was limited to only febrile neutropenic patients.

OBJECTIVE

This retrospective study estimated the rate of ABLC-associated nephrotoxicity in various clinical settings at a university hospital and compared that rate with previously reported rates of nephrotoxicity.

METHODS

Data from adult neutropenic and nonneutropenic patients receiving ABLC were collected and the degree of nephrotoxicity was determined using 2 definitions: (1) doubling of baseline SCr level using the peak value within the first 7 days, and (2) end-of-therapy doubling of baseline SCr level using the end-of-therapy value.

RESULTS

Data from 33 patients (20 men, 13 women; mean age, 48.6 years) were collected. Using these definitions of ABLC-associated nephrotoxicity, only 2 cases (6.1%) were observed. This rate was significantly below the 42.3% rate reported in the only large published study (95% CI, 1.7-19.6; P < 0.001). The median change in SCr level was 0.1 mg/dL (range, -1.1 to 4.3 mg/dL). Rates of change were higher in patients who died during hospitalization, but the difference was not significant. Use of concomitant nephrotoxic agents did not account for significant changes in SCr level.

CONCLUSIONS

Data from this study suggest that ABLC infrequently causes clinically significant nephrotoxicity. Therefore, when formulary decisions are made in the selection of a drug for use in various clinical settings, earlier data derived from a single study in febrile neutropenic patients that suggested a significantly higher rate of nephrotoxicity should be interpreted cautiously. Larger trials with more diverse patient populations are needed to better characterize institutional rates of ABLC-associated nephrotoxicity and to aid formulary decision makers.

Overview of the lipid formulations of amphotericin B

Invasive fungal infections have been increasingly recognized as a major cause of morbidity and mortality in the immunocompromised host. Amphotericin B has a broad spectrum and has remained the drug of choice for life-threatening invasive fungal infections. However, adverse events, particularly renal insufficiency, are limiting factors in achieving an effective dose: the prescription of amphotericin B is a compromise between toxicity and efficacy. Lipid formulations offer a better therapeutic index by circumscribing amphotericin B toxicity. Three lipid formulations are available in most countries: AmBisome, the only true liposome; Abelcet, with a ribbon-like structure; and Amphocil/Amphotec, composed of disc-like structures. All these formulations contain amphotericin B, but they differ in shape, size, reticuloendothelial clearance, C(max), AUC and visceral diffusion. The impact of these differences in pharmacokinetics and pharmacodynamics on clinical efficacy is still unclear. Efficacy has been shown in neutropenic patients with fever of unknown origin, systemic candidosis, invasive aspergillosis, cryptococcal meningitis and a variety of other difficult-to-treat mycoses, such as Fusarium or Zygomycetes infections. The effective dose may vary from one formulation to the other and is c. 3-5 mg/kg/day. All formulations are less nephrotoxic than amphotericin B. In one randomized double-blind study, AmBisome 3 or 5 mg/kg/day was less nephrotoxic and gave fewer infusion-related events than Abelcet 5 mg/kg/day. Abelcet induces fewer infusion-related side effects than Amphocil. All formulations seem at least as effective as amphotericin B. In some patients with life-threatening mycosis who failed treatment with, or were intolerant to, amphotericin B, the lipid formulations were effective. Further studies with comparable selected high-risk patients are warranted to clarify the usefulness and the indications of each of the formulations. Cost is a factor limiting prescription in many institutions, where use is often restricted to patients intolerant of, or refractory to, amphotericin B.

Liposomal amphotericin B versus conventional amphotericin B in the empirical treatment of persistently febrile neutropenic patients

Liposomal amphotercin B was compared with conventional amphotericin B for empirical antifungal therapy in febrile neutropenic patients in a randomized, double-blind, multicentre trial. Using a composite end-point, the two drugs were equivalent in overall efficacy. However, the liposomal amphotericin B treatment group had fewer proven fungal infections, fewer infusion-related side effects and less nephrotoxicity. Patient data from that study were analysed to compare the pharmacoeconomics of liposomal versus conventional amphotericin B therapy. Itemized billing data from 414 patients were collected and analysed. Hospital costs from first dose were significantly higher for all patients who received liposomal amphotericin B ($48,962 versus $43,183, P = 0.02). However, hospital costs were very sensitive to the cost of the study medication ($39,648 versus $43,048, when acquisition costs are not included, P = 0.4). Using decision analysis models and sensitivity analyses to vary the cost of study medications and risk of nephrotoxicity, the break-even points for the cost of liposomal therapy were calculated to range from $72 to $87 per 50 mg for all patients, and $83 to $112 per 50 mg in allogeneic bone marrow transplant patients. Therefore, the drug acquisition costs and the risk of nephrotoxicity are important factors in determining the cost-effectiveness of liposomal amphotericin B as empirical therapy in persistently febrile neutropenic patients. In a recent randomized double-blind study comparing liposomal amphotericin B at 3 or 5 mg/kg/day with amphotericin B lipid complex (ABLC) 5 mg/kg/day as empirical antifungal treatment in patients with febrile neutropenia, liposomal amphotericin B was associated with less toxicity than ABLC, both in terms of infusion-related reactions and nephrotoxicity. The incidence of study drug discontinuation due to toxicity was: liposomal amphotericin B 3 mg/kg/day, 14%; liposomal amphotericin B 5 mg/kg/day, 15%; and ABLC, 42% (P < 0.001).

Safety and efficacy of low-dose amphotericin B lipid complex for empirical antifungal therapy of neutropenic fever in patients with hematologic malignancies

Amphotericin B lipid complex (ABLC) has been investigated as an empirical antifungal treatment for neutropenic patients with persistent fever of unknown origin (FUO). We studied the safety and efficacy of low dose ABLC (1 mg/kg/day) for empirical treatment of neutropenic FUO. Sixty-one patients with hematologic malignancies developing 69 episodes of neutropenic FUO after chemotherapy or hematopoietic stem cell transplantation were included in the study. The median patient age was 47 years (18-68). The median duration of neutropenia (< 0.5 x 10(9)/l) was 17 days (7-45) and the median duration of ABLC therapy was 8 days (2-19). Thirteen patients (19%) suffered from mild to moderate infusion-related adverse events. Creatinine levels were stable in 42 cases (61%), improved in 9 (13%) and deteriorated in 18 (26%), with no other significant toxicities. Among 67 evaluable episodes, the response rate (resolution of fever during the period of neutropenia without developing a fungal infection) was 67%, while 33% were treatment failures. Low-dose ABLC is safe, well tolerated and seems to be at least as effective as c-AmB for empirical antifungal therapy of FUO. Randomized trials at this dose level comparing ABLC with c-AmB or other lipid formulations are warranted.

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.

Amphotericin B lipid complex or amphotericin B multiple-dose administration to rabbits with elevated plasma cholesterol levels: pharmacokinetics in plasma and blood, plasma lipoprotein levels, distribution in tissues, and renal toxicities

The purpose of the present study was to determine if a relationship exists between the plasma cholesterol concentration, the severity of amphotericin B (AmpB)-induced renal toxicity, and the pharmacokinetics of AmpB in plasma in hypercholesterolemic rabbits administered multiple doses of amphotericin B (AmB) deoxycholate (Doc-AmB) and AmB lipid complex (ABLC). After 7 days of administration of a cholesterol-enriched diet (0.50% [wt/vol]) or a regular rabbit diet, each rabbit was administered a single intravenous bolus of Doc-AmB (n = 8) or ABLC (n = 10) (1.0 mg/kg of body weight) daily for 7 consecutive days (a total of eight doses). Blood samples were obtained daily before and 24 h after the administration of each dose and serially thereafter following the administration of the last dose for the assessment of pharmacokinetics in plasma, kidney toxicity, plasma lipoprotein levels, and drug distribution in tissue. The pharmacokinetics of AmB in blood following the administration of ABLC were also determined in rabbits fed cholesterol-enriched and regular diets (n = 3 each group). Before drug treatment, cholesterol-fed rabbits demonstrated marked increases in total, low-density lipoprotein (LDL), and triglyceride-rich lipoprotein (TRL) cholesterol levels in plasma compared with the levels in rabbits on a regular diet. No significant differences in total plasma triglyceride levels were observed. Significant increases in plasma creatinine levels were observed in rabbits fed a cholesterol-enriched diet (P < 0.05) and rabbits fed a regular diet (P < 0.05) when administered AmB. However, the magnitude of this increase was twofold greater in rabbits fed a regular diet than in rabbits fed a cholesterol-enriched diet. An increase in plasma creatinine levels was observed only in rabbits on a cholesterol-enriched diet administered ABLC. The pharmacokinetics of AmB were significantly altered in rabbits on a cholesterol-enriched diet administered Doc-AmB or ABLC compared to those in rabbits on a regular diet administered each of these compounds. The pharmacokinetics of AmB in blood were significantly different following ABLC administration but not following Doc-AmB administration in both rabbits fed cholesterol-enriched diets and rabbits fed regular diets compared to their corresponding pharmacokinetics in plasma. An increased percentage of AmB was recovered in the TRL fraction when Doc-AmB was administered to rabbits fed a cholesterol-enriched diet than when it was administered to rabbits fed a regular diet. Furthermore, an increased percentage of AmB was recovered in the LDL and TRL fractions when ABLC was administered to rabbits fed a cholesterol-enriched diet rabbits fed a regular diet. These findings suggest that an increase in plasma cholesterol levels modifies the pharmacokinetics of AmB and renal toxicity following the administration of multiple intravenous doses of Doc-AmB and ABLC.

Efficacy of amphotericin B lipid complex in the treatment of invasive fungal infections in immunosuppressed paediatric patients

The safety and efficacy of amphotericin B lipid complex (ABLC) were evaluated in a retrospective study of 46 paediatric patients with invasive infections. The study included a large proportion of patients who were refractory to or intolerant of conventional antifungal therapy. The mean age of the children was 9.7 +/- 4.8 years. Primary underlying conditions included mainly haematopoietic stem cell transplantation, leukaemia and lung transplantation. The mean daily dose given was 4.11 mg/kg for a mean duration of 38.7 days. At the end of therapy, 38 of 46 (83%) patients responded successfully to treatment with ABLC, including 18 of 23 (78%) with aspergillosis and 17 of 19 (89%) with candidiasis. ABLC was well tolerated, with a low incidence of adverse events. The mean creatinine value was 74.5 microl/mol/l at baseline and 78.2 micromol/l at the end of therapy. These results support the use of ABLC in the treatment of invasive fungal infections in children, including patients who have previously failed, or are intolerant of, traditional antifungal regimens.

Comparison of amphotericin B lipid complex (ABLC) vs. ambisome in the treatment of suspected or documented fungal infections in patients with leukemia

Fungal infections remain a major cause of treatment failure and death in acute leukemia. New liposomal preparations of amphotericin B are now available. While less toxic, their comparative efficacy and toxicity profiles are unknown. In this study the comparative efficacy and safety of ABLC vs. AmBisome was evaluated in seventy-five patients with leukemia who developed 82 episodes of suspected or documented mycosis, and were treated (1:1) with either ABLC (n=43) or AmBisome (n=39). Both drugs were dosed accordingly from 3 to 5 mg/kg/day. Using an intent-to-treat analysis, the overall response to therapy was 27/43 (63%) for ABLC and 15/39 (39%) for AmBisome (p=0.03). Median dose and duration of treatment was 10 days at 3 mg/kg for ABLC and 15 days at 4 mg/kg for AmBisome. Acute, not dose-limiting infusion side effects were seen in 70% vs. 36% (p=0.002), ABLC vs. AmBisome. Increase of bilirubin > 1.5 times from baseline was 38% vs. 59%, ABLC vs. AmBisome (p=0.05). ABLC and AmBisome were equally effective for the treatment of suspected or documented fungal infections. While, acute infusion-toxicity was greater with ABLC, infusion toxicity requiring discontinuation was similar for both drugs. AmBisome was better tolerated than ABLC but was associated with mild abnormalities in liver function tests at the end of therapy.

Targeted prophylaxis with amphotericin B lipid complex in liver transplantation

The purpose of this study is to prospectively evaluate a strategy in which prophylaxis with amphotericin B lipid complex at 3 different dosages was targeted to liver transplant recipients at high risk for the development of invasive fungal infection (IFI). High risk was defined as a postoperative requirement for prolonged (>/=5 days) intensive care unit (ICU) treatment. Consecutive high-risk patients were administered prophylaxis with amphotericin B lipid complex from day 5 after orthotopic liver transplantation (OLT) until ICU discharge or death. The first 10 eligible patients were administered 5 mg/kg/d, the next 10 patients were administered 2.5 mg/kg/d, and a final 10 patients were administered 1 mg/kg/d. Drug safety and efficacy were assessed before each dosage reduction. During the study period, 130 adult patients underwent 137 OLTs. Thirty patients fulfilled the entry criteria and were administered prophylaxis with amphotericin B lipid complex. No patient developed proven IFI during prophylaxis. Cultures from normally sterile sites (blood and abdominal drain fluid) always showed negative results. All fungal isolates were sensitive in vitro to amphotericin B. There was no significant difference in colonization scores among the groups of patients administered different dosages of amphotericin B lipid complex. No death, serious adverse reaction, or nephrotoxicity was attributed to amphotericin B lipid complex. We conclude that prophylaxis with amphotericin B lipid complex targeted to patients requiring prolonged ICU treatment after OLT appears to be well tolerated and may prevent IFI. Our current policy is to use amphotericin B lipid complex, 1 mg/kg/d, as antifungal prophylaxis in this high-risk group.

Respiratory distress secondary to both amphotericin B deoxycholate and lipid complex formulation

A 73-y-old female with a history of adenocarcinoma of colon and refractory anemia developed febrile neutropenia following chemotherapy. Therapy with iv infusion of amphotericin B deoxycholate (AmBd) was initiated on day 8 of hospital admission. Premedications included acetaminophen, diphenhydramine and meperidine. Patient developed rigor, chill and elevated temperature approximately 100 min into the infusion. The infusion was temporarily discontinued and rigors subsided following administration of 25 mg meperidine im. Infusion was continued after cessation of the rigors with no further sequelae. During each infusion of AmBd over the next 3 d, the patient developed rigor, chill and elevated temperature which was managed with meperidine. However, on day 4 she developed respiratory distress, bronchospasm and visible cyanosis with oxygen saturation of 88% while on 2 L oxygen. The infusion was stopped and the symptoms subsided with administration of albuterol via nebulizer. Amphotericin lipid formulation infusion was reinstituted after 3 d because of the patient's worsening clinical status. However, the patient developed severe respiratory distress approximately 130 min into the infusion. The infusion was discontinued and she was treated with albuterol via nebulizer. Itraconazole therapy was instituted without any adverse sequelae. Clinicians should be aware of this potential adverse event since it can occur with all formulation of amphotericin.

Amphotericin B lipid complex (ABLC)-associated hypertension: case report and review

Amphotericin B (AmB) continues to be the mainstay of therapy for serious fungal infections, despite its relatively toxic side-effect profile. Lipid preparations of the medication have been marketed in the past few years in an attempt to reduce some of these side effects, especially nephrotoxicity. Although 6 cases of severe hypertension associated with the use of AmB deoxycholate have been reported in the literature, no cases of hypertension associated with a lipid-containing preparation of the medication have been reported. We report here the first case of severe hypertension associated with the infusion of AmB lipid complex (ABLC) in a patient with multiple intraperitoneal and urinary fungal pathogens. We also provide a brief review of the previously reported cases of hypertension associated with the deoxycholate formulation of AmB.

Retrospective analysis of the dosage of amphotericin B lipid complex for the treatment of invasive fungal infections

STUDY OBJECTIVE

To understand the relationship between dosage and therapeutic response of amphotericin B lipid complex (ABLC) by analyzing underlying diseases, types of infections, and therapeutic outcomes with different dosages as second-line antifungal therapy.

DESIGN

Retrospective analysis of low-dose (initial dose < or = 3 mg/kg) ABLC from three open-label, clinical, second-line treatment studies.

SETTING

Centers in the United States (204), Canada (3), Australia (1), Mexico (1), and The Netherlands (1).

PATIENTS

Five hundred fifty-one patients (5 enrolled twice) with invasive fungal infections, of whom 289 failed and 267 were intolerant to conventional antifungal therapy.

INTERVENTIONS

Patients were to receive the recommended dosage of ABLC 5 mg/kg/day, with dosage reduction for markedly increased serum creatinine. The duration of treatment was 4 weeks; therapy could be extended if the investigator considered additional treatment necessary.

MEASUREMENTS AND MAIN RESULTS

Seventy-three patients (13%) received ABLC 3 mg/kg/day (low dosage) instead of the protocol-recommended 5 mg/kg/day Response was 65% and 56%, respectively. Logistic regression analysis revealed that the following patients are most likely to start therapy at the lower dosage: those with candidiasis and other yeast infections, patients with nephrotoxicity due to prior amphotericin B, and those with underlying conditions other than hematologic malignancy.

CONCLUSION

These results suggest that ABLC 3 mg/kg/day may be effective in treating patients with candidiasis who do not have hematologic malignancy.

Amphotericin B lipid complex in pediatric patients with invasive fungal infections

BACKGROUND

Lipid formulations of amphotericin B have been recently introduced for treatment of invasive fungal infections. However, little is known about their role in pediatric populations.

METHODS

We studied the safety and antifungal efficacy of amphotericin B lipid complex (ABLC, Abelcet) in 111 treatment episodes in pediatric patients through an open label, emergency use multicenter study. Patients with invasive fungal infections were enrolled if they had mycoses refractory to conventional antifungal therapy, if they were intolerant of previous systemic antifungal agents or concomitant nephrotoxic drugs or if they had preexisting renal disease.

RESULTS

All 111 treatment episodes were evaluable for safety and 54 were evaluable for efficacy. The mean serum creatinine for the study population did not significantly change between baseline (1.23 +/- 0.11 mg/dl) and cessation of ABLC therapy (1.32 +/- 0.12 mg/dl) during 6 weeks. There were no significant differences observed between initial and end-of-therapy levels of serum potassium, magnesium, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and hemoglobin. However, there was an increase in mean total bilirubin (3.66 +/- 0.73 to 5.31 +/- 1.09 mg/dl) at the end of therapy (P = 0.054). Among 54 cases fulfilling criteria for evaluation of antifungal efficacy, a complete or partial therapeutic response was obtained in 38 patients (70%) after ABLC therapy. Complete or partial therapeutic response was documented in 56% of cases with aspergillosis (n = 25) and in 81% (n = 27) with candidiasis. Among premature infants (n = 8) and allogeneic marrow recipients (n = 14), response rates were 88 and 57%, respectively. Response was similar in those patients enrolled because of intolerance to previous antifungal therapy or because of progressive infection.

CONCLUSIONS

These data support the use of ABLC for treatment of invasive fungal infections in pediatric patients who are intolerant of or refractory to conventional antifungal therapy.

Pharmacokinetics, distribution in serum lipoproteins and tissues, and renal toxicities of amphotericin B and amphotericin B lipid complex in a hypercholesterolemic rabbit model: single-dose studies

The purpose of this study was to determine if a relationship exists among total serum and lipoprotein cholesterol concentration, the severity of amphotericin B (AmpB)-induced renal toxicity, and the serum pharmacokinetics of AmpB in hypercholesterolemic rabbits administered AmpB and AmpB lipid complex (ABLC). After 10 days of cholesterol-enriched diet (0.50% [wt/vol]) or regular rabbit diet (control), each rabbit was administered a single intravenous bolus of AmpB or ABLC (1.0 mg/kg of body weight). Blood samples were obtained before administration and serially thereafter for the assessment of serum pharmacokinetics, kidney toxicity, and serum lipoprotein distribution. Rabbits were humanely sacrificed after all blood samples were obtained, and tissues were harvested for drug analysis. Before drug treatment, cholesterol-fed rabbits demonstrated marked increases in total serum cholesterol and low-density lipoprotein (LDL) cholesterol levels compared with levels in rabbits on a regular diet. No significant differences in triglyceride levels were observed. A significant increase in serum creatinine levels was observed in cholesterol-fed and regular diet-fed rabbits administered AmpB. However, the magnitude of this increase was 2.5-fold greater in cholesterol-fed rabbits than in regular diet-fed rabbits. No significant differences in triglyceride levels were observed. A significant increase in serum creatinine levels was observed in cholesterol-fed and regular diet-fed rabbits administered ABLC. Whereas AmpB pharmacokinetics were significantly altered in cholesterol-fed rabbits administered free AmpB, similar AmpB pharmacokinetics were observed in both rabbit groups administered ABLC. Renal AmpB levels were significantly increased in cholesterol-fed rabbits administered AmpB compared with those in all other groups. Hepatic and lung AmpB levels were elevated in cholesterol-fed rabbits administered free AmpB compared to controls. In addition, hepatic, lung, and spleen AmpB levels were significantly decreased in cholesterol-fed rabbits administered ABLC compared to controls. An increased percentage of AmpB was recovered in LDL-very-low-density lipoprotein fraction when free AmpB was administered to cholesterol-fed rabbits compared with those in all other groups. These findings suggest that increases in cholesterol, specifically, LDL cholesterol levels, modify the disposition and renal toxicity of free AmpB. However, the pharmacokinetics and renal toxicity of ABLC were independent of elevations in total and LDL cholesterol levels.

Hyperkalemia associated with rapid infusion of conventional and lipid complex formulations of amphotericin B

A child developed hyperkalemia and cardiac arrest with infusion of an amphotericin B lipid complex 5.0 mg/kg over 1 hour. Another child, with chronic renal failure, developed hyperkalemia after infusion of conventional amphotericin B deoxycholate 1.0 mg/kg over 2 hours. Rapid infusion of the agent causes hyperkalemia in dogs and humans that is exacerbated in the setting of renal failure. A lipid formulation of amphotericin B is commercially available, and no reports of hyperkalemia are associated with its administration.

Amphotericin B lipid complex for invasive fungal infections: analysis of safety and efficacy in 556 cases

The safety and antifungal efficacy of amphotericin B lipid complex (ABLC) were evaluated in 556 cases of invasive fungal infection treated through an open-label, single-patient, emergency-use study of patients who were refractory to or intolerant of conventional antifungal therapy. All 556 treatment episodes were evaluable for safety. During the course of ABLC therapy, serum creatinine levels significantly decreased from baseline (P < .02). Among 162 patients with serum creatinine values > or = 2.5 mg/dL at the start of ABLC therapy (baseline), the mean serum creatinine value decreased significantly from the first week through the sixth week (P < or = .0003). Among the 291 mycologically confirmed cases evaluable for therapeutic response, there was a complete or partial response to ABLC in 167 (57%), including 42% (55) of 130 cases of aspergillosis, 67% (28) of 42 cases of disseminated candidiasis, 71% (17) of 24 cases of zygomycosis, and 82% (9) of 11 cases of fusariosis. Response rates varied according to the pattern of invasive fungal infection, underlying condition, and reason for enrollment (intolerance versus progressive infection). These findings support the use of ABLC in the treatment of invasive fungal infections in patients who are intolerant of or refractory to conventional antifungal therapy.

Renal effects of amphotericin B lipid complex

A study was conducted to compare the renal effects of amphotericin B lipid complex (ABLC), a lipid formulation of the widely used antifungal medication, with conventional amphotericin B (AmB) in the treatment of serious fungal infections, including invasive candidiasis, cryptococcal meningitis, and aspergillosis. The clinical experience of ABLC includes two types of open-label studies: randomized comparative (ABLC 5 mg/kg/d compared with AmB 0.6 to 1 mg/kg) and emergency use. In the comparative studies, changes in serum creatinine were evaluated three ways: doubling of the baseline value, an increase from < or = 1.5 mg/dL at baseline to > or = 1.5 mg/dL, and an increase from < or = 1.5 mg/dL at baseline to > or = 2.0 mg/dL. More patients in the AmB group reached these end points than in the ABLC group (P < or = 0.007), and the time needed to reach each of these end points was significantly shorter for the AmB group (P < or = 0.02). Increased serum creatinine was reported as an adverse event more frequently by patients receiving AmB than by patients receiving ABLC. In the emergency use study, a steady and statistically significant decrease in serum creatinine was observed among patients who started ABLC treatment with serum creatinine greater than 2.5 mg/dL due to prior AmB treatment. ABLC offers the physician a valuable, less-nephrotoxic alternative to AmB for the treatment of patients with severe, invasive fungal infections.