Shares of ACADIA Pharmaceuticals (NASDAQ:ACAD) shot through the roof today, up 30% as of this filming. In the video below, Fool health-care analyst David Williamson discusses news of some great phase 3 trial results for the company's drug Pimavanserin, which treats psychosis in patients with Parkinson's disease. David tells investors how good the results were, and what advantages this drug candidate could have over its competition if it reaches FDA approval.

David Williamson owns shares of Pfizer. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not 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.