[Reproductive and developmental toxicity study of suplatast tosilate (IPD-1151T) (4)--Perinatal and postnatal study in rats by oral administration]

In order to assess the effect of suplatast tosilate (IPD-1151T) on pregnancy of the rat, and the post natal development to maturity of the F1 generation, daily doses of 0 (control), 200, 600 and 1800 mg/kg/day were administered orally to female Wistar rats from day 17 of pregnancy to day 21 after delivery. All females were allowed to give birth and rear their young to weaning. F0 dams showed no treatment-related changes in general conditions including the state of delivery or nursing, gestation period, birth rate, or autopsy findings. The dams at 1800 mg/kg/day showed a tendency to reduction in body weight gain and a decrease in food consumption. F1 offspring showed no treatment-related changes in clinical signs on the birth day or during the nursing period, external examination on the birth day, general condition, physical or reflex development, open-field test, water multiple T-maze test, autopsy findings, organ weights, skeletal examination, reproductive ability, or histopathological examination on the reproductive organs of the animals of both sexes that failed to produce pregnancy. The offspring at 1800 mg/kg/day showed a reduction or its tendency in body weight gain. There were no treatment-related changes in any of reproductive parameters of F1 dams including external examination of F2 fetuses. The results suggest that the non-effective dose level of IPD-1151T is 600 and 1800 mg/kg/day for F0 dams in general toxicity and reproductive ability, respectively, and 600 mg/kg/day for F1 offspring in post natal development under the conditions of this study.