Acute and 26-Week Repeated Oral Dose Toxicity Study of UP446, a Combination of Scutellaria Extract and Acacia Extract in Rats

UP446 has been used in both joint supplements and prescription medical food. The purpose of this study was to evaluate the pharmaceutical safety of UP446 via acute and 26-week repeated oral dose toxicity study in SD rats. In acute toxicity study, UP446 was administered by oral gavage to Sprague-Dawley rats (5 males and 5 females) at a dose of 5000 mg/kg. In 26-week repeated oral dose toxicity study, UP446 at doses of 500, 1000 and 2000 mg/kg/day were given orally to groups of rats (10 rats/dose/sex) for 26-week. UP446 at a dose of 5000 mg/kg produced no treatment-related acute toxicity or mortality in any of the animals tested during 14 days of the study. In 26-week repeated dose toxicity study, there was no significant difference in body weight between the control and all treatment groups. Blackish stool and soft stool was observed in one male in the 1000 mg/kg group and in some males and females of 2000 mg/kg group. However, these changes of stool were not considered to be toxic effects because neither histopathological change in gastrointestinal tracks (GIT) nor body weight change were detected. No drug induced abnormalities were found as of body weights, food consumption, ophthalmological examinations, urinalysis, hematology, clinical chemistry, organ weights and gross necropsy in any animals in the dosing groups. These results suggest that the oral lethal dose of UP446 for male and female rats is in excess of 5000 mg/kg and the no observed adverse effect level (NOAEL) of the UP446 for both male and female rats is considered to be greater than 2000 mg/kg/day.