Novel approaches to drug development along with incentives to reward risk undertaken during early drug development have been proposed to improve the medical product development process. The American College of Clinical Pharmacology held its 19th Frontiers Symposium in mid-2007 to provide a forum to share new knowledge about disease progression models and adaptive and other novel trial designs. These topics reflect the changing paradigm of drug development and regulatory innovation as outlined in the Food and Drug Administration's Critical Path Initiative. This meeting report summarizes some of the presentations and panel discussions among academic, industrial, and regulatory participants regarding clinical trial design, including adaptive Bayesian approaches.