This is a randomized placebo-controlled, double-blind, parallel-group, enriched enrollment randomized withdrawal study assessing the efficacy and safety of nabilone for non-motor symptoms in patients with Parkinson´s Disease. Nabilone is an analogue of tetrahydrocannabinol (THC), the psychoactive component of cannabis. Nabilone acts as a partial agonist on both Cannabinoid 1 (CB1) and Cannabinoid 2 (CB2) receptor in humans and therefore mimics the effect of THC but with more predictable side effects and less euphoria.~Part 1 is the open-label dose adjustment phase of the study. In Part 1, eligible subjects, who have signed the informed consent form at the screening visit, will receive open-label nabilone starting with a dosage of 0.25 mg in the evening. During dose titration and optimization, nabilone will be titrated in 0.25 mg increments (increase by 0.25 mg/ every one to four days) up to a maximum dose of 1 mg twice daily. Patients should be on a stable nabilone dose for at least 1 week afterwards until Baseline Visit (V 0).~Part 2 is the placebo-controlled, double-blind, parallel-group randomized withdrawal phase of the study. At Baseline Visit, treatment responders will be included in Part 2 of the study (randomized placebo-controlled, double-blind, parallel-grouped). Responders are randomized in a 1:1 ratio at Baseline Visit to receive either nabilone or matching placebo for 4 weeks + 2 days. The placebo-controlled, double-blind, randomized withdrawal phase will end with a clinic visit (Termination Visit V 1). Following this, the study medication will be tapered in all patients. During this period the patients will receive phone calls every other day. A Safety Telephone Call and a Safety Follow-Up Visit will be performed.
This is a randomized placebo-controlled, double-blind, parallel-group, enriched enrollment randomized withdrawal study assessing the efficacy and safety of nabilone for non-motor symptoms in patients with Parkinson´s Disease. Nabilone is an analogue of tetrahydrocannabinol (THC), the psychoactive component of cannabis. Nabilone acts as a partial agonist on both Cannabinoid 1 (CB1) and Cannabinoid 2 (CB2) receptor in humans and therefore mimics the effect of THC but with more predictable side effects and less euphoria.~Part 1 is an open-label dose adjustment phase of the study. In eligible patients, a screening period is followed by an open-label nabilone dose optimization phase and a stable phase for at least 1 week. Treatment responders will be included in Part 2 of the study (randomized placebo-controlled, double-blind, parallel-grouped).~Part 2 is the placebo-controlled, double-blind, parallel-group randomized withdrawal phase of the study.