Dec 20 (Reuters) - Acadia Pharmaceuticals Inc said on Tuesday its drug to treat psychosis in patients suffering from Alzheimer's disease met its main goal in a mid-stage study.

The company said the drug, pimavanserin, showed a statistically significant reduction in psychosis, compared with placebo.

The drug has been approved by the US Food and Drug Administration to treat hallucinations and delusions associated with Parkinson's disease psychosis, the company said.

Acadia said the FDA is yet to approve any drug to treat Alzheimer's disease psychosis.

(Reporting by Akankshita Mukhopadhyay in Bengaluru; Editing by Anil D'Silva)