Evaluation of levamlodipine benzenesulfonate compound I for embryo-fetal developmental toxicity in SD rats and genotoxicity

Abstract

In the present study, the effects of levamlodipine benzenesulfonate on the development of fertile Sprague-Dawley (SD) rats, their embryos, and littermates were assessed using an embryo-fetal developmental toxicity test. Maternal body weight reduction was observed at a dose of 20 mg/kg, but it recovered after treatment cessation. The 20 mg/kg dose group showed a skewed sex ratio in fetal rats, with a higher proportion of males. While some effects on fetal sternum development were observed at 20 mg/kg, no skeletal malformations were observed. No significant gross morphological abnormalities were detected in the dams (mothers), no significant embryotoxicity or foetotoxicity in fetal rats and no significant effects on fetal length and weight development at doses of 5 and 10 mg/kg. Genotoxicity was evaluated using a combination of the Ames test, the Chinese hamster ovary (CHO) cell chromosome aberration assay, and the ICR mouse bone marrow micronucleus test. The Ames test results indicated substantial bacteriostatic effects at doses of 500 and 5000 mg/dish, with no mutagenicity observed at doses of 0.5, 5, and 50 mg/dish. No significant effect on the aberration rate of CHO cell chromosomes was found at doses of 2.8, 5.6, and 11.2 mg/mL. In the ICR mouse micronucleus test, no micronucleus-inducing effect was observed at doses of 3.125, 6.25, and 12.5 mg/kg in each treatment group. In conclusion, under the conditions of this experiment, the no-observed-adverse-effect level (NOAEL) for developmental toxicity of levamlodipine benzenesulfonate in fertile SD rats, their embryos, and littermates was established to be 10 mg/kg/day. Levamlodipine benzenesulfonate did not exhibit significant genotoxicity.