Open-Label Phase 3 Study to Examine the Long-Term Safety, Tolerability and Efficacy of APL-130277 for the Acute Treatment of "OFF" Episodes in Patients With Parkinson's Disease

De Novo Subjects Inclusion Criteria

• Male or female ≥ 18 years of age.
• Clinical diagnosis of Idiopathic PD, consistent with UK Brain Bank Criteria (excluding the "more than one affected relative" criterion)
• Clinically meaningful response to L-Dopa as determined by the Investigator.
• Receiving stable doses of L-Dopa/carbidopa (immediate or CR) administered at least 4 times per day OR Rytary™ administered at least 3 times per day, for at least 4 weeks before the initial Screening Visit (SV1). Adjunctive PD medication regimens must be maintained at a stable dose for at least 4 weeks prior to the initial Screening Visit (SV1) with the exception that MAO-B inhibitors must be maintained at a stable level for at least 8 weeks prior to the initial Screening Visit (SV1).
• No planned medication change(s) or surgical intervention anticipated during the course of study.
• Subject must experience at least one well defined "OFF" episode per day with a total daily "OFF" time duration of ≥ 2 hours during the waking day, based on patient self-assessment.
• Subject and/or caregiver must be trained in performing home dosing diary assessments of the motor state and must be able to recognize "ON" and "OFF" states.
• Stage III or less on the modified Hoehn and Yahr scale in the "ON" state.
• MMSE score > 25.
• If female and of childbearing potential, must agree to be sexually abstinent or use one of the following highly effective methods of birth control:
• Hormonal contraceptives (eg, combined oral contraceptives, patch, vaginal ring, injectables, and implants);
• Intrauterine contraceptive system;
• Surgical sterilization or partner sterile (must have documented proof); AND

One of the following effective methods of birth control:

• Male/female condom;
• Cervical cap with spermicide;
• Diaphragm with spermicide;
• Contraceptive sponge.
• Male subjects must be either surgically sterile, agree to be sexually inactive or use a double-barrier method of birth control (eg, condom and diaphragm with spermicide, condom with cervical cap and spermicide) from first study drug administration until 90 days after final drug administration.
• Willing and able to comply with scheduled visits, treatment plan, laboratory tests, and other study-related procedures.
• Able to understand the consent form, and to provide written informed consent.

De Novo Subjects Exclusion Criteria -

• Atypical or secondary parkinsonism.
• Previous treatment with any of the following: a neurosurgical procedure for PD; continuous s.c. apomorphine infusion; Duodopa/Duopa; or APL-130277.
• Treatment with any form of s.c. apomorphine within 7 days prior to the second Screening Visit (SV2). Patients that stopped s.c. apomorphine for any reason other than systemic safety concerns or lack of efficacy may be considered.
• Contraindications to APOKYN®, or hypersensitivity to apomorphine hydrochloride or any of the ingredients of APOKYN® (notably sodium metabisulfite).
• Female who is pregnant or lactating.
• Participation in a clinical trial within 30 days prior to the initial Screening Visit (SV1).
• Receipt of any investigational (ie, unapproved) medication within 30 days prior to the initial Screening Visit (SV1).
• Currently taking selective 5HT3 antagonists (ie, ondansetron, granisetron, dolasetron, palonosetron, alosetron), dopamine antagonists (excluding quetiapine or clozapine) or dopamine depleting agents.
• Drug or alcohol dependency in the past 12 months.
• Subject has a history of malignancy within 5 years prior to the Screening visit, except for adequately treated basal cell or squamous cell skin cancer or in situ cervical cancer. Pituitary tumors of any duration are excluded.
• Clinically significant medical, surgical, or laboratory abnormality in the opinion of the Investigator.
• Major psychiatric disorder including, but not limited to, dementia, bipolar disorder, psychosis, or any disorder that, in the opinion of the Investigator, req