Safety and efficacy of dose escalated liposomal amphotericin B in adult leukemia patients with refractory invasive fungal infections: A single institution report.

Abstract

6613 Background: Leukemia patients are at risk for invasive fungal infections(IFI). Empiric therapy of suspected IFI is begun due to fever despite appropriate antibiotics during neutropenia or infiltrates on chest CT. Liposomal amphotericin B (L-AmB) is used for empiric anti-fungal therapy at 3-5 mg/kg. Data is lacking on the efficacy of L-AmB dose escalation in patients with CT progression and clinical decline. Methods: Patients who received 10 mg/kg of L-AmB from 2002-11. They were required to be ≥18 years old and escalated from 5 to 10 mg/kg L-Amb for at least 7 doses. Patient information was collected from pharmacy and medical records. Successful treatment was defined as resolution of fever at least 1 week after high dose L-AmB and/or improvement or stability on chest CT. Renal and hepatic toxicity was assessed. Clinical remission was defined as recovery of a normal neutrophil count. IRB approval was obtained for this study. Results: 58 patients were evaluated. At the time of presumed or probable IFI, 19 had completed induction therapy, 5 had received supportive therapy, and 34 had received 2 or more cycles of therapy. High dose L-AmB was begun for CT findings and fever, CT findings only, and fever only in 14, 26, and 17 patients, respectively. Patients received a median of 15 doses of high dose L-AmB, and all received concomitant therapy with an echinocandin except two: 1 received nothing and 1 received voriconazole. Treatment success was seen in 28 (48%) patients. Twenty-nine (50%) patients were alive at 12 weeks and 10 (17%) patients proceded to BMT. Only 11 (39%) of the responding patients achieved a clinical remission. All patients received IV hydration and electrolyte repletion. Six patients had a grade 2 increase in serum creatinine and 10 patients developed grade 2 or 3 hepatic toxicity. There were no grade 4 adverse events. Conclusions: Although it has been reported that L-AmB at 10mg/kg was inferior to 3 mg/kg in untreated patients, our study supports a safe dose escalation strategy to 10mg/kg in treating progressive presumed or probable IFI and should be considered a clinical alternative for these high risk patients.