A 4-week subcutaneous toxicity study of recombinant human interferon alpha A (LBD-007) in Sprague-Dawley rats

Recombinant human interferon alpha A (code name: LBD-007) was subcutaneously administered to both sexes of Sprague-Dawley rats at the doses of 0, 6, 12 and 24 x 10(6) IU/kg of body weight five days per week for 4 weeks to evaluate the subchronic toxicity. 20 to 50% of rats except the male control group showed minimal to mild, focal to multifocal renal mineralization. Whether renal mineralization is related to the test substance is not elucidated. Male rats dosed at 24 x 10(6) IU/kg showed the decrease of the absolute kidney weights and the increase of the brain relative weights. Female rats dosed at 24 x 10(6) IU/kg showed the increase of the absolute and relative ovary weights, and the decreases of specific gravity, bilirubin and urobilinogen in urine. However, no drug-related changes were noted in clinical findings, body weights, food consumption, water consumption, hematology, blood clinical chemistry and necropsy findings. Based on the results it is concluded that the estimated subcutaneous non-toxic dose of the recombinant human interferon alpha A (LBD-007) in rats is (6 approximately 12) x 10(6) IU/kg.