Preclinical Evaluation

Preclinical evaluation is an essential component of any drug development program aimed at taking promising new agents from the laboratory to the treatment of cancer patients. This has become especially important for ALL, since the majority of children afflicted with the disease in developed countries now survive due to improvements in multiagent chemotherapy and supportive care, and the number of adults and children available for enrolment in clinical trials of new drugs is limited. Therefore, it has become essential to prioritise new drugs for clinical trials in ALL using the best available experimental models. Unfortunately, history tells us that preclinical models frequently overestimate drug efficacy, ultimately leading to disappointment in the clinic. Nevertheless, there remains a relative paucity of data in which preclinical testing results were directly compared with a drug’s efficacy in clinical trials. Consequently, there is a need to develop the methodology to systematically prioritise new drugs for clinical trials in ALL using stringent criteria that do not overestimate efficacy, and to then test the predictive power of these preclinical models in clinical trials. This chapter will review the current status of efforts to systematically prioritise new drugs for clinical trials in ALL.