Liposomal amphotericin B (AmBisome): safety data from a phase II/III clinical trial

AmBisome is a commercially available preparation of amphotericin B incorporated in small unilamellar liposomes. The analysis of safety data provided in a multicentre compassionate phase II/III study evaluating 133 episodes of therapy with AmBisome in patients with severe underlying disease is very encouraging. Rapid (30-60 min) administration of a high daily dose of AmBisome is feasible without the well known side effects observed with the conventional formulation of amphotericin B (Fungizone). Although eleven of 71 patients with initially normal serum creatinine concentrations showed increased values after AmBisome therapy, 17 patients among 50 with initially high creatinine concentrations recovered normal renal function during AmBisome treatment. Hypokalaemia was observed in 24 episodes of treatment (18%). Increases in serum glutamyl oxaloacetic transaminase and alkaline phosphatase were also quite common in this selected population with severe underlying disease and the contribution of AmBisome to these changes is difficult to establish. AmBisome appears a safe alternative to conventional amphotericin B, and its efficacy should be further investigated.