The primary objective in Stage 1 is to determine an acceptably safe dose, utilizing the continual reassessment method (CRM).The CRM is a model-based statistical procedure for conducting phase I clinical trials that assigns doses to successive cohorts of patients based on the doses given and outcomes observed (toxicity or no toxicity) of all previous patients. In this sense, the method is "outcome-adaptive." The CRM relies on a simple Bayesian model for the probability of toxicity as a function of dose. As the dose-toxicity data in the trial accumulate the Bayesian model "learns" about the relationship between dose and probability of toxicity. Numerous computer simulation studies (and the references therein) have shown that the CRM has greatly superior properties compared to conventional "3+3" algorithms. This is due to the facts that conventional algorithms are not model-based, they only use data from the most recent 6 patients, and they tend to stop the trial very early, with the consequences that they are very likely to give very unreliable estimates of the toxicity probability at each dose and provide an unreliable recommended maximum tolerated dose (MTD).