The present invention provides a controlled-release composition containing tozadenant, at least one cellulose ether, and one or more pharmaceutically acceptable excipients. In the composition, the tozadenant is present in an amount ranging from about 30% (w/w) to about 65% (w/w) based on the total composition weight； and the cellulose ether is present in an amount sufficient to provide: not less than about 10% and not more than about 30% tozadenant dissolution over a 2-hour test period, not less than about 55% tozadenant dissolution over a 10-hour test period, and not less than about 80% tozadenant dissolution over a 16-hour test period. Use of the composition for treatment of Parkinson's disease is also described.
