- Step-by-step Crm, The Introduction Of Start Rules. I Stage Of Clinical Trials

The main purpose of phase I clinical trials is to estimate the maximum tolerated dose of a new drug which will be passed for further testing in phase II trials.In fact,phase I clinical trials are performed in many medicals areas,but are particularly important in cancer,because of the severity of side-effects of cytotoxic drugs to treat cancers. Meanwhile,a certain degree of side-effects is acceptable when administering cytotoxic drugs because most cancers are rapidly fatal and effective therapies are rare.In this paper, the estimation of the maximum tolerated dose of a drug for phase I clinical trials is investigated. Various designs from philosophical and statistical standpoints have been presented for years. Especially since O'Quigley,Pepe and Fisher presented a new approach of the continual reassessment method in 1990,there have been many papers focusing on this problem with Bayesian design,and a lot of progress has been made.The paper not only inherits the idea of Stepwise CRM in Tao(2002) but also brings in the setup rule, which will make great improment over the Curve-free CRM in Gasparini and Eisele(2000). The results show that these modifications will reduce both time of the trials and the toxicity percentage,which will be propitious to the clinical application of this method.