The Alzheimer's Divide

Issues of clinical trial design are at the forefront in Alzheimer's drug development. Researchers and investors are weighing the impact of late-stage failures, even as significant unknowns remain about disease mechanism and the correlation of biochemical markers and clinical effects. A fundamental question hangs over AD drug development, which is unique in many respects: in deciding how to move from Phase II into Phase III, what can you know and how can you know it?