Cataractogenic effect of cyclosporin A: a new adverse effect observed in the rat.

In a study designed to test the long-term nephrotoxic effects of cyclosporin A (CyA), 11 of 13 rats given CyA, 25 mg/kg per day for 8 months, developed cataract. None of the 15 rats given CyA 12.5 mg/kg per day, nor of the controls given vehicle only (n = 10), developed this lesion. In a subsequent study, 15 rats were given CyA 25 mg/kg per day, 15 were given 12.5 mg/kg per day, and 10 controls were given the vehicle only. After 16 weeks, three rats of the group on CyA 25 mg/kg per day had developed cataract. The SPF Sprague-Dawley rats were maintained on a controlled breeding diet (Ewos R3). Perforating eye lesions or infections were not observed, but one rat without opacity of the lens had antibodies against sialodacryoadenitis virus. Thus, in the rat, high-dose CyA has significant cataractogenic effects when administered for 15%-25% of the rat life-span.