Inhibitory effects of repeated intravenous injections of dexamethasone on pulmonary toxicity of a new mitomycin C analogue, KW-2149, in a novel rat model.

An animal model for testing pulmonary toxicity of KW-2149, a new mitomycin C analogue, was developed (by intravenously injecting 3.28 mg/kg of the drug into male SD rats 3 times at weekly intervals), and exhibits pleural effusion from 1 week after the last injection. In this animal model, repeated intravenous injections of dexamethasone (DM), following any of three different schedules examined, were more or less effective of reducing the amount of effusion. The optimal results were obtained with 4 administrations a week (i.e. twice before and twice after KW-2149 treatment). The results of the present experiment suggest possible clinical application of DM in protecting patients from pulmonary toxicity of KW-2149.