Acadia Pharmaceuticals CEO Steve Davis

Acadia Pharmaceuticals’ treatment for Parkinson’s disease-related psychosis failed a Phase 3 trial that was studying use of the drug for schizophrenia patients who haven’t fully responded to existing therapies.

The company announced the trial failure Monday after market close. Acadia (NASDAQ: ACAD) shares dropped about 4 percent on the news in after-hours trading, falling from just shy of $26 each to about $22 apiece.

Acadia’s study of its drug pimavanserin enrolled 396 people with moderate-to-severe psychotic symptoms that had shown some improvement with their current treatment but continued experiencing symptoms (what’s known as an “inadequate” response). Those existing treatments had Read more »