Abstract: The present disclosure relates to a more effective therapeutic agent capable of improving and treating the axial symptoms (particularly freezing of gait symptom) of patients with Parkinson's disease. Such symptoms in patients with Parkinson's disease can be improved and treated by using L-threo-3,4-dihydroxy-phenylserine (DOPS) and a COMT inhibitor in combination together, optionally with an L-DOPA preparation as well. As a result, the axial symptoms difficult to improve with conventional L-DOPA preparations can be treated, and a therapeutic agent and a treatment method are provided for the axial symptoms of patients with Parkinson's disease, particularly those suffering from the disease at a moderate level or higher.

Abstract: The present invention relates to pharmaceutical formulations for the controlled delivery of threo-3-(3,4-dihydroxyphenyl)serine (threo-DOPS) and derivatives of it. Such formulations can contain an extended or slow release component that maintains therapeutic concentration of threo-DOPS in the blood plasma over a prolonged time period. They can be further combined with an immediate release formulation to produce a product that, when administered to a patient in need thereof, results in substantially steady levels of active drug, eliminating the sharp peaks and troughs in blood plasma drug levels experienced with the existing threo-DOPS formulations.