A three month dietary toxicity study of RH-5849 was conducted in Cr1:CD BR rats in order to determine the potential toxic effect produced in this species by the test compound. One hundred twenty rats were employed in the study and dietary dose levels of 0, 1, 10, 100, 1000 and 2000 ppn were used. The following pathology report presents the histomorphological evaluation of all the tissues for the control and 2000 ppn groups, all rats dying during the study and all gross lesions. In addition all potential target organs, kidney, liver, spleen, lungs, thyroids (and parathyroids when available) , bone and bone marrow, brain, spinal cord and peripheral nerve, were examined for animals of the intermediate dose levels. Also, gross necropsy data, organ weight data and clinical laboratory (hematology and chanistry) data were reviewed.