Adaptive dose insertion in early phase clinical trials

Background and Purpose We propose to adaptively insert new doses during the course of a dose-finding trial when none of the prespecified doses in the trial are acceptable, for example, have tolerable toxicity. Methods Our procedure uses an activation rule to determine whether a new dose is needed and an inverse dose response algorithm to estimate new doses to be inserted into the trial. Results The proposed method can be applied to both one-agent and two-agent trials. In application to a Phase I trial about advanced ovarian cancer, our method selected a new dose that is better than all prespecified doses in at least 44% simulations. The effectiveness of the procedure was also demonstrated in a simulation study. Limitations The proposed method is applicable to dose-finding trials with binary responses. Conclusions We believe that with the added adaptive dose insertion, traditional dose-finding trials will have better chances of locating desirable doses. In addition, by allowing for. dose insertion, unnecessary trial suspension due to lack of acceptable doses can be avoided. Clinical Trials 2013; 10: 216-224. http://ctj.sagepub.com