Introduction

In the past several decades, it has been recognized that increasing spending for biomedical research does not re¨ect an increase in the success rate of pharmaceutical (clinical) development. Woodcock (2005) indicated that the low success rate of pharmaceutical development could be due to (1) a diminished margin for improvement that escalates the level of difŒculty in proving drug beneŒts, (2) genomics and other new sciences have not yet reached their full potential, (3) mergers and other business arrangements have decreased candidates, (4) easy targets are the focus as chronic diseases are harder to study, (5) failure rates have not improved, (6) rapidly escalating costs and complexity decrease the willingness/ability to bring many candidates forward into the clinic. In the early 2000s, the U.S. Food and Drug Administration (FDA) kicked off a Critical Path Initiative to assist the sponsors in identifying the scientiŒc challenges underlying the medical product pipeline problems. In its 2004 Critical Path Report, the FDA presented its diagnosis of the scientiŒc challenges underlying the medical product pipeline problems.