Acute toxicological evaluation of AT-533 and AT-533 gel in Sprague-Dawley rats.

Background: AT-533 is a novel heat shock protein 90 inhibitor that exerting anti-inflammatory, antiviral, and antitumor efficacy. Furthermore, the gel made of AT-533 as raw material named AT-533 gel has the function of repairing keratitis and dermatitis caused by herpes virus infection. However, the acute safety evaluation of AT-533 and AT-533 gel has not been conducted.

Methods and results: Herein, we performed acute toxicological studies of AT-533 and AT-533 gel in Sprague-Dawley rats. Fifteen-day acute toxicity study of AT-533 was conducted in both male and female Sprague-Dawley rats at doses of 5, 50, 250 and 500 mg/kg and AT-533 gel at 5 g/kg in the study. During experiment, food consumption and mortality were observed and body weight, hematology, serum biochemistry and histopathological assessment of rats were carried out. No abnormal changes were observed in rats percutaneously treated with AT-533 at 5 mg/kg and 50 mg/kg and AT-533 gel. However, loss of appetite and body weight, adverse reactions, toxicologically relevant alterations in hematology and biochemistry were found in rats percutaneously treated with AT-533 at 250 mg/kg and 500 mg/kg during 15-day acute dermic toxicity study.

Conclusions: The aforementioned results suggested that the LD₅₀ of AT-533 is 228.382 mg/kg and the LD₅₀ of AT-533 gel is greater than 5 g/kg. These findings indicated that AT-533 is non-toxic in rats when the dose less than 50 mg/kg and AT-533 gel can be considered a gel with no toxicity at doses less than 5 g/kg.