April 18 (Reuters) - Cerevel Therapeutics ( CERE ) said

on Thursday its Parkinson's disease drug improved symptom

control in patients when tested as an add-on therapy, meeting

the main goal in a late-stage study.

The trial, which enrolled 507 adults, tested Cerevel's

tavapadon as an add-on therapy to levodopa, the standard of care

for the nervous system disorder that causes progressive brain

damage and impacts movement.

The disease affects about 1 million people in the United

States.

The results showed that patients using these two drugs

experienced an increase of 1.1 hours in total "on" time without

involuntary and erratic movements, compared to those treated

with levodopa and placebo.

A statistically significant reduction was recorded in "off"

time, periods of sudden spike in symptoms when movement becomes

more difficult.

Patients between the ages of 40 and 80, diagnosed with

Parkinson's disease and experiencing motor fluctuations, were

enrolled in the trial.

The patients were on a stable dose of levodopa for at least

four weeks prior to screening.

The drug developer said it will share additional data from

late-stage trials testing the once-daily treatment tavapadon as

a monotherapy in the second half of 2024.

In December, AbbVie ( ABBV ) agreed to buy Cerevel

Therapeutics ( CERE ) for about $8.7 billion. The deal is expected to

close in the middle of 2024.