On May 30,2018 ,Investigators intend to conduct a multicenter, randomized, double-blind, placebo-controlled study of idebenone in the treatment of early-stage Parkinson's disease with motor and non-motor symptoms which is to observe the therapeutic effect of idebenone on motor symptoms and non-motor symptoms in patients with early Parkinson's disease。

This clinical trail was a multicenter, parallel, randomized, double-blind, placebo-controlled study led by Professor Liu Chunfeng from the Second Affiliated Hospital of Suzhou University which consisted of 15 sub-centers with a total of 180 subjects.

This clinical study is divided into two phases:

The first stage: double-blind period, 24 weeks. Three queues containing idebenone 180 mg/d,360 mg/d and placebo.

The second stage: open label extension period, 24 weeks. All enrolled participants continued to take idebenone 180 mg/d to study the long-term effects of idebenone.

Inclusion Criteria:

• (1) Male or female, age > 30 years old, ≤ 80 years old;
• (2) Conforms to the "Diagnostic Criteria for Parkinson's Disease" developed by the 2015 International Association of Sports Disabilities (MDS);
• (3) Patients with early Parkinson's disease, duration <3 years, Hoehn-Yahr classification:1-3, MMSE scale score ≥ 24 points;
• (4)Receiving a stable dose of dopamine agonist or monoamine oxidase type B inhibitor for treatment before the enrollment;
• (5) The subjects need to sign the Informed Consent Form（ICF）

Exclusion Criteria:

• (1)Patients with disturbance of consciousness, aphasia and mental illness; patients with major depression (HAD scale score ≥ 15 points)
• (2)Patients with Parkinson's superimposition syndrome and patients with secondary Parkinson's syndrome (hepatolenticular degeneration, hepatic encephalopathy, cerebellar disease, hydrocephalus, parathyroid disease, etc.)
• (3)Patients who have long-term use of dopamine blockers (such as potent neuroleptics, sibutramine, reserpine, metoclopramide, etc.);
• (4)Patients who have taken coenzyme Q10 or idebenone within three months;
• (5) Patients taking amantadine and levodopa need to stop taking the drug for more than one month before the enrollment;
• (6)Patients with severe cardiopulmonary dysfunction, liver and kidney dysfunction (more than 3 times normal);
• (7)Patients who cannot cooperate with the neuropsychological test;
• (8) Patients with poor compliance, not following the prescribed treatment regimen.