Clinical considerations in the design of clinical trials

The clinical trial is the tool used to improve the survival and quality of life for cancer patients through clinical research. The essence of any good clinical trial is an idea worth testing. The multiplicity of questions that can be asked in clinical research requires flexibility in the design of clinical trials. The controversy that rises between randomized trials versus historical control trials at times ignores the reality that different questions require different clinical trial methodologies. Whether a trial is randomized or not should not be viewed as an ethical question, but instead as a strategic question. One way to look at clinical trials is to divide them into exploratory, confirmatory, and explanatory studies. The explanatory study takes an established regimen and attempts to modify and/or dissect it to improve its therapeutic index. Each of these trial types requires a different mix of strategies which must also be impacted upon by the exigencies of a disease-oriented approach to clinical research. Long-term adjuvant chemotherapy trials are new and long-term analysis must be a sine qua non. While the initial analysis will be relapse-free survival versus acute toxicity, the ultimate analysis will entail balancing overall survival with chronic toxicity.