Alzheimer's Disease is a devastating condition affecting millions of Americans. At this time, there is no cure. In 2021, Biogen's Aduhelm (aducanumab) received FDA approval under the accelerated approval pathway after a controversial approval process. This case explores Alzheimer's drug development, Aduhelm's clinical trials, FDA regulatory processes, the impact of the disease on payors and the broader healthcare system, the valuation of an Alzheimer's therapy, and the valuation of the company that produces it.