Intestinal Levodopa + Entacapone Therapy (Lecigon®) to Counteract Dopaminergic Desensitization and Neuropsychiatric Complications in Parkinson's Disease

Inclusion criteria

• Understand and voluntarily sign an informed consent document prior to any study related assessments/procedures. 2. Able to adhere to the study visit schedule and other protocol requirements. 3. Female Subject of childbearing potential1 and male subjects with female partner of childbearing potential1 is willing to use highly effective contraceptive methods during the study (adequate: combined hormonal contraception associated with inhibition of ovulation, progestogen-only hormonal contraception associated with inhibition of ovulation, intrauterine device, intrauterine hormone-releasing system, bilateral tubal occlusion, vasectomized partner2, sexual abstinence3). 1. For the purpose of this document, a female is considered of childbearing potential (FCBP), i.e. fertile, following menarche and until becoming post-menopausal unless permanently sterile. Permanent sterilisation methods include hysterectomy, bilateral salpingectomy and bilateral oophorectomy. A postmenopausal state is defined as no menses for 12 months without an alternative medical cause. A high follicle stimulating hormone (FSH) level in the postmenopausal range may be used to confirm a post-menopausal state in women not using hormonal contraception or hormonal replacement therapy. However in the absence of 12 months of amenorrhea, a single FSH measurement is insufficient. For the purpose of this document, a man is considered fertile after puberty unless permanently sterile by bilateral orchidectomy 2. Vasectomized partner is a highly effective birth control method provided that partner is the sole sexual partner of the WOCBP trial participant and that the vasectomized partner has received medical assessment of the surgical success 3. In the context of this guidance sexual abstinence is considered a highly effective method only if defined as refraining from heterosexual intercourse during the entire period of risk associated with the study treatments. The reliability of sexual abstinence needs to be evaluated in relation to the duration of the clinical trial and the preferred and usual lifestyle of the subject. 4. All subjects must agree not to share medication. 5. Diagnosis of Idiopathic PD, inclusive of familial PD and genetic forms of L-Dopa responsive PD Age 18 - 75 years 7. Age at Parkinson's disease onset before 65 years 8. Disease duration ≥ 5 years 9. Oral medication constant for four weeks prior to baseline visit 10. Oral treatment with L-Dopa and non-ergot dopamine agonist(s) (any preparation, any dosage) 11. Presence of dopaminergic motor fluctuations based on patient history 12. Presence of dopaminergic neuropsychiatric (affective) fluctuations based on patient history 13. Presence of behavioural hyperdopaminergic syndrome including clinically relevant neuropsychiatric behavioural abnormalities according Ardouin Behavioural Scale Section 1, hypomanic symptoms, psychosis + Section 4 hyperdopaminergic behaviours (score ≥ 3), eventually further accompanied by impulse control disorders, a/o dopamine dysregulation, syndrome, a/o hallucination - psychosis spectrum; in case symptoms of the hallucination/psychosis or hypomania-mania spectrum are present, retained insight is mandatory at the time of study enrolment