The technology relates in part to methods for controlling elimination of therapeutic cells, for example, cells that express a chimeric antigen receptor. The technology further relates to a two-step method of controlling destruction of therapeutic cells in a patient following an adverse event. The two-step system may include a rapamycin or rapamycin analog-based level of control and a second, rimiducid, level of control. The technology also relates in part to methods for cell therapy using cells that express the inducible caspase polypeptide and the rapamycin-sensitive polypeptide, where the proportion of therapeutic cells eliminated by apoptosis is related to the choice and amount of the administered ligand.
