Abstract
In non-clinical toxicity evaluations for drug development, the primary objective is to elucidate the target organs of toxicity induced by the test-article and the relationship between the dosage and exposure. Moreover, it is important to determine whether the observed changes are reversible or not, for risk assessment. In the general toxicity studies, the reversibility of changes may be scientifically discussed based on the characteristics, extent, and severity of the lesion, and regenerative capacity of the organ which showed the toxicity. However, when it is difficult to predict reversibility, it should be evaluated by conducting a study that includes a drug-free period after the administration period. Although it is not necessary to observe the complete reversibility, drug-free period will be carefully set to examine reversibility, as the half-life of some drugs, such as antibody drugs, is long.
In this presentation, it will be introduced the overview of common concept of reversibility evaluation and the settings of recovery animals and drug-free period in the general toxicity studies.
