Conditions: Parkinson Disease Idiopathic Parkinson Disease
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 839
Healthy volunteers: no

Brief summary:
The primary purpose of this extension study is to assess the long-term safety and tolerability of preladenant in participants from parent studies NCT01155466 \[P04938\] and NCT01227265 \[P07037\] with moderate to severe Parkinson's Disease (PD). The study will also characterize the long-term efficacy of preladenant in participants with PD.

Participants will continue to receive their stable regimen of levodopa (L-dopa) plus any adjunct medications during the study as prescribed by their physician. Several classes of adjunct medications may be used, including Amantadine, anticholinergics, dopa decarboxylase inhibitors, and dopamine agonists.

Detailed description:

Arms:
arm 1: Participants who received preladenant 2 mg in parent study NCT01155466 or NCT01227265 will continue to receive preladenant 2 mg in this extension study. Participants will receive preladenant 2 mg taken orally twice daily (BID): one tablet plus placebo capsule to rasagiline in the morning, and one tablet in the evening, for 40 weeks. arm 2: Participants who received preladenant 5 mg in parent study NCT01155466 or NCT01227265 will continue to receive preladenant 5 mg in this extension study. Participants will receive preladenant 5 mg taken orally BID: one tablet plus placebo capsule to rasagiline in the morning, and one tablet in the evening, for 40 weeks. arm 3: Participants who received placebo to preladenant tablet in parent study NCT01155466 or NCT01227265 will receive preladenant 5 mg in this extension study. Participants will receive preladenant 5 mg taken orally BID: one tablet plus placebo capsule to rasagiline in the morning, and one tablet in the evening, for 40 weeks. arm 4: Participants who received preladenant 10 mg in parent study NCT01155466 or NCT01227265 will continue to receive preladenant 10 mg in this extension study. Participants will receive preladenant 10 mg taken orally BID: one tablet plus placebo capsule to rasagiline in the morning, and one tablet in the evening, for 40 weeks. arm 5: Participants who received rasagiline 1 mg in parent study NCT01155466 or NCT01227265 will continue to receive rasagiline 1 mg in this extension study. Participants will receive rasagiline 1 mg capsule once a day: one capsule plus placebo tablet to preladenant in the morning, and one placebo tablet to preladenant in the evening, for 40 weeks. arm 6: Participants who received placebo to rasagiline capsule in parent study NCT01155466 or NCT01227265 will receive rasagiline 1 mg in this extension study. Participants will receive rasagiline 1 mg capsule once a day: one capsule plus placebo tablet to preladenant in the morning, and one placebo tablet to preladenant in the evening, for 40 weeks.

Interventions: intervention 1: Preladenant intervention 2: Rasagiline intervention 3: Placebo to preladenant intervention 4: Placebo to rasagiline
Intervention descriptions: intervention 1: Daily for 40 weeks: 2, 5, or 10 mg preladenant tablet each morning; 2, 5, or 10 mg preladenant tablet each evening (approximately 8 hours after the morning dose) intervention 2: Daily for 40 weeks: 1 mg rasagiline capsule each morning intervention 3: Placebo to match preladenant given daily for 40 weeks: placebo tablet each morning; placebo tablet each evening (approximately 8 hours after the morning dose) intervention 4: Placebo to match rasagiline given daily for 40 weeks: placebo capsule each morning

Protocol document: