Reproductive and developmental toxicity study of suplatast tosilate (IPD-1151T) (3)--Teratological study in rabbits by oral administration

Abstract

A teratological study of suplatast tosilate (IPD-1151T), a newly developed anti-allergic agent, was carried out in pregnant NZW rabbits to assess the effects on dams and fetuses. IPD-1151T was administered to dams orally at dose levels of 0, 100, 300, 450 and 700 mg/kg/day from day 6 through day 18 of gestation, and their fetuses were removed for teratological evaluation. The results were as follows: 1. In dams, marked increase in the incidence of abortion, and decrease in body weight gain, food consumption and feces mass were shown in the 700 mg/kg/day group. Slight decrease in body weight gain and food consumption were seen in the 450 mg/kg/day group, but no toxicities were observed in the 300 mg/kg/day or less groups. 2. In fetuses, marked increase in embryo-fetal deaths and decrease in alive fetal body weights and placental weights, but no teratogenicity were shown in the 700 mg/kg/day group. There were no fetal toxicity or teratogenicity in the 450 mg/kg/day or less groups. 3. No effective dose levels were 300 mg/kg/day for maternal general toxicity and 450 mg/kg/day for maternal reproductive toxicity and for fetuses.