Conditions: Parkinson Disease
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 12
Healthy volunteers: no

Brief summary:
This is a randomized, placebo-controlled, 3-period crossover, balanced, single-site, third party-blind study of preladenant (SCH 420814) in participants with Parkinson disease (PD) to be conducted in conformance with Good Clinical Practices. This trial will investigate the effects of single doses of preladenant and placebo on the dyskinesia and antiparkinsonian actions of a levodopa infusion. The study will examine 10 mg ("low dose") or 100 mg ("high dose") study drug, given as single, oral administrations in conjunction with intravenous (IV) levodopa infusion and oral carbidopa.

Detailed description:

Arms:
arm 1: Participants were to receive their assigned experimental treatment based on randomly assigned treatment sequence at Hour 0 following an overnight withdrawal of their antiparkinsonian medications of each treatment period. The levodopa infusion was to be started at Hour 1 and was to run for 2 hours. The participants were to also receive 25 mg of carbidopa at the following times: Hours 0, 2, and 4. Treatment periods were to be separated by at least 7 days but not more than 28 days washout between each dose. arm 2: Participants were to receive their assigned experimental treatment based on randomly assigned treatment sequence at Hour 0 following an overnight withdrawal of their antiparkinsonian medications of each treatment period. The levodopa infusion was to be started at Hour 1 and was to run for 2 hours. The participants were to also receive 25 mg of carbidopa at the following times: Hours 0, 2, and 4. Treatment periods were to be separated by at least 7 days but not more than 28 days washout between each dose. arm 3: Participants were to receive their assigned experimental treatment based on randomly assigned treatment sequence at Hour 0 following an overnight withdrawal of their antiparkinsonian medications of each treatment period. The levodopa infusion was to be started at Hour 1 and was to run for 2 hours. The participants were to also receive 25 mg of carbidopa at the following times: Hours 0, 2, and 4. Treatment periods were to be separated by at least 7 days but not more than 28 days washout between each dose. arm 4: Participants were to receive their assigned experimental treatment based on randomly assigned treatment sequence at Hour 0 following an overnight withdrawal of their antiparkinsonian medications of each treatment period. The levodopa infusion was to be started at Hour 1 and was to run for 2 hours. The participants were to also receive 25 mg of carbidopa at the following times: Hours 0, 2, and 4. Treatment periods were to be separated by at least 7 days but not more than 28 days washout between each dose. arm 5: Participants were to receive their assigned experimental treatment based on randomly assigned treatment sequence at Hour 0 following an overnight withdrawal of their antiparkinsonian medications of each treatment period. The levodopa infusion was to be started at Hour 1 and was to run for 2 hours. The participants were to also receive 25 mg of carbidopa at the following times: Hours 0, 2, and 4. Treatment periods were to be separated by at least 7 days but not more than 28 days washout between each dose. arm 6: Participants were to receive their assigned experimental treatment based on randomly assigned treatment sequence at Hour 0 following an overnight withdrawal of their antiparkinsonian medications of each treatment period. The levodopa infusion was to be started at Hour 1 and was to run for 2 hours. The participants were to also receive 25 mg of carbidopa at the following times: Hours 0, 2, and 4. Treatment periods were to be separated by at least 7 days but not more than 28 days washout between each dose.

Interventions: intervention 1: SCH 420814 10 mg intervention 2: SCH 420814 100 mg intervention 3: Placebo intervention 4: Levodopa intervention 5: Carbidopa
Intervention descriptions: intervention 1: one 10-mg capsule, orally, at hour 0 of treatment period intervention 2: single oral dose of four SCH 420814 25-mg capsules at hour 0 of treatment period intervention 3: Placebo capsule, oral, at hour 0 of treatment period intervention 4: levodopa intravenous (IV) infusion (1 mg/kg body weight) was beginning 1 hour after study drug administration and continued for 2 hours intervention 5: one 25-mg table, orally, at hours 0, 2 and 4 of each treatment period

Protocol document: