The goal of this multicentric prospective randomized controlled clinical and economic study is to investigate the effectiveness and cost-utility of long-term continuous intraduodenal infusion of levodopa ( DUODOPA), compared to best medical treatment, on advanced and severe form of Parkinson's disease.

Inclusion criteria :

• Age> 18 years and ≤ 80 years
• Akineto-hypertonic and/or tremor forms of Parkinson's disease as defined by the criteria of the French National Consensus conference for Parkinson's disease (March 2000)
• Absence of parkinsonism other than a Parkinson's disease, including absence of one or more of the following signs: autonomic syndrome, hallucinations, pyramidal signs, early postural instability, early cognitive impairment (including apraxia or severe frontal lobe syndrome) (Consensus Conference, March 2000)
• Severe and advanced forms of Parkinson's disease with sensitivity to L-dopa (≥ 40%)
• No contraindication to Duodopa®: hypersensitivity to levodopa and carbidopa, or any of the excipients, angle-closure glaucoma, kidney and liver failures, severe heart failure, severe cardiac arrhythmia, acute stroke, pheochromocytoma, hyperthyroidism, Cushing syndrome, association with non-selective MAOIs and selective MAOIs-A (stop at least 2 weeks before initiation of Duodopa®)
• Fluctuations in motor performance (with OFF time ≥ 2 hours per day) and/or dyskinesia induced by L-DOPA altering significantly the activities of daily life in spite of an optimized treatment
• Hoehn and Yahr score < 4 in best ON
• Ability to complete a diary of self-evaluation (with the help of another person if necessary)
• MMSE ≥ 24/30
• No evolutive psychosis or history of severe psychosis requiring hospitalization
• No digestive disease or ENT evolutionary
• No concomitant treatment by continuous infusion of apomorphine
• No concomitant treatment by deep brain stimulation
• No serious somatic disease likely to interfere with a good participation to the study, contraindication for gastrostomy
• Menopause proven or woman of childbearing potential with an effective contraception (hormonal / mechanical: oral, injectable, transdermal, implantable, intrauterine device, or surgery: ligation of the fallopian tubes, hysterectomy, total ovariectomy)

Exclusion Criteria:

• Age <18 and> 80 years
• No signature of the informed consent form
• Patient with no social insurance or who cannot benefit it through a third person in accordance with the French law on biomedical research
• Population under enhanced protection (i.e minors), pregnant women, breast-feeding women, persons deprived of their liberty by a judicial or administrative decision, people in health and social service, adults under legal protection, and finally patients in emergency situations.