Chronic toxicity studies are performed for a period of 180 days to 1 year. During the study, the potential risks in relation to the anticipated dose and period of drug treatment, prospective targets of toxicity, and reversibility of clinical signs are observed.
Service details: Treatment design and duration both depend on a therapeutic treatment schedule. The standard study design includes 1-3 tested doses per route in animals of both sexes, 1 vehicle-dosed group, 20 animals per group. On average, 280 animals (including satellite groups) and 6-12 months are required for this study. Animals are observed daily for signs of toxicity, body weights are recorded weekly, and food intake can be measured weekly. Blood samples are collected for hematology and clinical chemistry analysis at selected intermediate time points and at the end of the test period. A gross necropsy is performed at all endpoints of the study. Histopathology is also available upon request. A customized design is available.