Cassava Sciences' Alzheimer's drug simufilam failed its Phase 3 trial and the stock plummeted ~90%. See why I changed my rating on SAVA to Sell from Strong Sell.

The Cassava Sciences story ended Monday exactly as many knew it would — with the company’s experimental drug for Alzheimer’s disease, simufilam, failing a clinical trial.

In March, pharmaceutical company Cassava Sciences made headlines for a report by the Food and Drug Administration (FDA) that cast doubt on the positive trial results of its novel Alzheimer’s drug, simufilam.