The general content and format of pharmacology/toxicology information to be included in the submission of an IND can be found in 21 CFR 312.23 (a)(8). The regulation states that “The kind duration, and scope of animal and other tests required vary with the duration and nature of the proposed clinical investigations.” The design and conduct of preclinical pharmacological and toxicological studies are thus important to inform regulatory decisions regarding the administration of an investigational cellular immunotherapy product in humans. These considerations will be discussed in addition to available FDA guidances, including FDA “Guidance for Industry: Preclinical Assessment of Investigational Cellular and Gene Therapy Products”. Lastly, the presentation will highlight the mechanisms for early communication with pharmacology/toxicology staff in CBER’s Office of Tissues and Advanced Therapies (OTAT) to obtain feedback on the preclinical development program.