A 2 Treatment Period Study with Period 1 Comprising a 3-Week Randomised, Double-Blind, Crossover Comparison of Apomorphine Nasal Powder (2 and 4 mg) and Placebo in Combination with a 12-Week Open, Active, Efficacy, safety and Tolerability Assessment of APO Nasal Powder (2 and 4 mg) in the Alleviation of Acute Episodes of Motor Symptoms Associated with PD, Followed by Period 2 Comprising a 36-Week Open, Active Treatment, Safety Assessment of APO Nasal Powder (2 and 4 mg), in Subjects with PD. - Apomorphine Nasal Powder (2 and 4 mg) and Placebo in Subjects with Parkinson's Disease

INTERVENTION: Product Name: Apomorphine Nasal Powder Pharmaceutical Form: Nasal powder Other descriptive name: 6aß ‐ apomorphine‐10,11‐diol hydrochloride hemihydrate Concentration unit: % (W/W) percent weight/weight Concentration type: equal Concentration number: 10‐ Pharmaceutical form of the placebo: Nasal powder Route of administration of the placebo: Nasal use CONDITION: Alleviation of acute episodes of motor symptoms associated with Parkinson's Disease PRIMARY OUTCOME: Main Objective: To determine the safety and local tolerability of repeated once daily dosing with Apomorphine Nasal Powder 2 and 4 mg over a period of 12 weeks, in subjects with Parkinson’s disease. Primary end point(s): The main efficacy endpoint is:· The time to initial improvement in the acute ‘off’ episode of Parkinsonian motor symptoms, as recorded in the diary card. The mean time for each subject in each treatment period will be calculated from the available data. Secondary Objective: ‐ To determine the effect of once daily dosing with Apomorphine Nasal Powder 2 and 4 mg in comparison with Placebo Nasal Powder based on time to alleviate a daily acute episode of Parkinsonian motor symptoms (’off’ episode) over a period of 7 days for each blinded week and compared to Baseline, in subjects with Parkinson’s disease. ; ; ‐ To determine the effect of once daily dosing with Apomorphine Nasal Powder 2 and 4 mg in comparison with Placebo Nasal Powder based on the UPDRS (Sections 18‐31) rating scale recorded in the clinic at 15 and 30 min post dose at Visits 1, 2 and 3, in subjects with Parkinson’s disease.; ; ‐ To determine the efficacy, safety and local tolerability of repeated once daily dosing with Apomorphine Nasal Powder 2 and 4 mg over a period of 48 weeks, in subjects with Parkinson’s disease.; ; ‐ To assess changes in quality of life at Visit 7 and Visit 16 and compared to Baseline in subjects with Parkinson’s disease. INCLUSION CRITERIA: At Screening Visit: 1. Ability and willingness to give written informed consent 2. Males and females aged 18 years and over 3. History of Parkinson’s disease for at least 1 year prior to screening 4. Documented medication for Parkinson’s disease for at least 6 months prior to screening 5. Currently on established, stable treatment for Parkinson’s disease (i.e. unchanged in the last 4 weeks) 6. Subjects naïve to subcutaneous apomorphine 7. At least one documented predictable or unpredictable daily acute episode of Parkinsonian motor symptoms (’off’ episode) that persists for longer than 30 minutes and resolves the same day 8. Willingness to take oral domperidone as anti‐emesis prophylaxis for the duration of the blinded phase of the study and if required during open label 9. Willingness to agree not to change the dose of their usual Parkinsonian medication for the duration of blinded phase (except i