Shares of Aeterna Zentaris (NASDAQ:AEZS) were gutted on the market Monday, down 25% intraday. In this video, Motley Fool health-care analyst David Williamson takes a look at a horrendous 12-month period for the company overall, and how hanging its hopes on its drug Perifosine has resulted in disappointment after disappointment in clinical trials.

David Williamson has no position in any stocks mentioned. The Motley Fool owns shares of Dendreon. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.