Phase 3 trial results for Acadia's (NASDAQ:ACAD) drug pimavanserin in treating Parkinson's disease psychosis are in, and the results are very positive. This type of psychosis can affect more than half of all Parkinson's sufferers, and the drug showed statistical significant advantages over a placebo group in reducing hallucinations and delusions. While other anti-psychotics that have been used to treat it off-label, they've been met with only limited success and have sometimes been detrimental to other motor skill treatments for patients, something not found in pimavanserin. The resulting market reaction: Shares of Acadia are up an astounding 140%.

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