Acadia's Parkinson's drug shows promise in treating Alzheimer's psychosis

Acadia Pharmaceuticals ($ACAD) may have struck two birds with one stone thanks to its pipeline drug pimavanserin. The drug, which is in Phase III development to treat Parkinson's disease psychosis, may also combat psychosis in Alzheimer's patients, according to the company.

Scientists discovered the breakthrough while testing the drug in mice exhibiting psychosis-like behavior. After they received pimavanserin, their symptoms subsided, according to an Acadia release. The drug also reversed augmented responses to amphetamine and normalized prepulse inhibition. More about the discovery can be found in this month's issue of the scientific journal Behavioural Pharmacology.

If Acadia can replicate those results in human patients, pimavanserin would be a breakthrough in treating Alzheimer's disease psychosis (ADP). Up to 50% of the 5.4 million Americans with the disorder may develop ADP, which doesn't have an FDA-approved therapy available in the U.S. Doctors can presently treat ADP with antipsychotics, but there are risks, according to Acadia CEO Uli Hacksell.

"Physicians often resort to off-label use of antipsychotic medications in patients with ADP despite their association with increased mortality and potential worsening of cognitive disturbances," Hacksell said in a statement. "These new findings suggest that pimavanserin may be ideally suited to address the need for a new ADP treatment that is safe, effective and well tolerated."

The discovery puts pimavanserin back in good graces. After a disastrous late-stage study three years ago that saw Acadia's stock plummet 70%, reports The Wall Street Journal, the company's shares closed Monday at $1.88, up nearly 3%. Acadia's stock is up 69% so far this year.  

- here's Acadia's statement
- get more from WSJ (sub. req.)