Clinical and Morphological Aspects in Assessing the Safety of OSPL-502 with Repeated Dose Administration

BACKGROUND: OSPL-502 is a new potential medicinal drug which stimulates a cognitive function. It is necessary to reveal clinical manifestations of its general toxic effect and determine organs that are most heavily affected by this pharmacological substance. AIMS: To describe and estimate clinical and histopathological changes in the organism of experimental animals in response to the repeated administration of pharmacological substance OSPL-502. MATERIAL AND METHODS: The study was conducted by the OECD Guidelines (Test No. 407) on Sprague-Dawley rats. The drug was administered at the dose of 20, 60 and 180 mg/kg. RESULTS: The repeated doses of OSPL-502 have not caused any toxic effects on the growth of body weight, food and water consumption of the tested animals, or affected the musculoskeletal system and exploratory behaviour of the rats in the doses of 20 and 60 mg/kg. The dose of 180 mg/kg (1800 times larger than the therapeutic dose) has shown clinical signs of toxicity in females but has not resulted in the death of the animals. Due to morphological methods, we have found histostructural changes in the liver, kidneys and adrenal glands of the rats that were treated with the test substance in the maximum dose. These changes are reversible and reduce within 14 days after the admission of the studied substances is cancelled. CONCLUSION: OSPL-502 at the dose of 180 mg/kg has a weakly pronounced toxic effect, the dose of 60 mg/kg is the threshold, and that of 20 mg/kg is no-observable-adverse-effect-level (NOAEL); the liver, kidneys and adrenal glands can be considered target-organs for the tested substance.