(Reuters) – Acadia Pharmaceuticals Inc said on Wednesday dementia patients taking its drug Nuplazid were nearly three times less prone to a psychotic relapse than those on placebo.

The drugmaker’s late-stage trial testing Nuplazid, stopped in September after positive results, enrolled 392 patients aged 74.5 years on average.

Patients on the drug experienced a 65% reduction rate in relapses of dementia-related psychotic episodes, the company said.

Chief Executive Officer Stephen Davis said Acadia planned to meet with the U.S. regulator in the first half of next year to discuss filing for Nuplazid’s approval to include dementia-linked psychosis on its label.

There are no FDA-approved treatments for the condition, characterized by hallucinations and delusions.

The company estimates there are about 2.4 million dementia-related psychosis patients in the United States, about 70% of whom have Alzheimer’s.

About 1.2 million patients have been diagnosed and are being treated with older-generation anti-psychotics and anti-depressants, Davis noted.

Acadia said 4.8% of patients taking Nuplazid had serious side effects, compared with 3.6% of patients in the placebo group.

Nuplazid was approved to treat psychosis linked to Parkinson’s disease in 2016 and Acadia recorded net product sales of $223.8 million last year.

The drug comes at a list price of $3,100 a month.

Acadia, also testing Nuplazid for use in patients with schizophrenia and major depressive disorder, declined to comment on future pricing.

(Reporting by Tamara Mathias, Dania Nadeem and Deena Beasley; Editing by Shinjini Ganguli)