Retinal toxicity of intravitreally injected faeriefungin

Faeriefungin is a new antibacterial and antifungal agent derived from a strain of Streptomyces griseus var. autotrophicus. Under anesthesia, 12 albino rabbits underwent injection in their right eyes with 400, 200, 100, 40, 20, and 10 micrograms of faeriefungin. Retinal toxicity was assessed by electroretinography and light and transmission electron microscopy. Injection of 400 micrograms resulted in severe retinal toxicity, although indirect ophthalmoscopy was unremarkable. At 200 micrograms, there was moderate toxicity. Intravitreal injection of concentrations of 100 micrograms or less produced no neuroretinal toxicity. These data suggest that faeriefungin is a potentially useful drug in the treatment of fungal or bacterial endophthalmitis.