New target-based agents involve new clinical trial designs.

Clinical cancer investigation is performed through clinical trials. Development and measurement of clinical efficacy of new target-based agents differs from classic cytotoxic drugs. Whereas the aim of chemotherapy drugs is to destroy tumoral cells, new agents try to inhibit cell profileration without a clear tumor shrinkage. The main endpoint for phase I trials is to determine the optimal biological response with the least toxicity; oncopharmacogenomic studies must be performed in tumoral biopsies to assess the target inhibition. Time to progression and biological activity are the endpoints for phase II studies. Finally, phase III trials will determine overall survival.