Ocular toxicity of intravitreally injected liposomal amphotericin B in rhesus monkeys.

We determined whether liposome-intercalated amphotericin B was less toxic than commercial amphotericin B when injected intravitreally in the primate. Three rhesus monkeys were studied on each of three occasions. Each eye received increasing doses of amphotericin B (10, 20, or 30 micrograms) or liposome-intercalated amphotericin B (40, 80, or 120 micrograms) as a single intravitreal injection. There were often transient inflammatory changes in the anterior chamber and all eyes showed an acute cellular infiltrate in the vitreous humor after injection. These reactions had resolved by eight weeks after injection of the low or intermediate doses of amphotericin B (10 or 20 micrograms) or liposome-intercalated amphotericin B (40 or 80 micrograms) but left a mild vitreal infiltrate in the high-dose groups (30 micrograms of amphotericin B or 120 micrograms of liposome-intercalcated amphotericin B). Histologic examination at the end of the third experiment showed no abnormalities. These studies suggest that liposome incorporation reduces the toxicity of amphotericin B by at least fourfold and that as much as 30 micrograms of commercial amphotericin B may be tolerated by the intravitreal route in the rhesus monkey.