When used in combination with levodopa, Requip (ropinirole) patches result in greater improvements in motor function compared to placebo for patients with advanced Parkinson’s disease, a Phase 3 clinical trial has found.
Trial findings also demonstrated the effectiveness of the new skin patch formulation was not inferior to Requip’s oral extended-release tablet formulation, suggesting the Requip skin patch may be a viable alternative option for patients.
Findings were reported in the study, “Ropinirole Patch Versus Placebo, Ropinirole Extended-Release Tablet in Advanced Parkinson’s Disease,” published in the journal Movement Disorders.
Parkinson’s disease is a neurodegenerative disorder characterized by the gradual loss of dopamine-producing neurons in the substantia nigra — a region of the brain responsible for movement control — leading up to a series of motor impairments.
Levodopa, a chemical that can be converted to dopamine in the brain, currently is the main form of treatment used to ease the motor symptoms of Parkinson’s.
However, its long-term use can have multiple side effects, including a “wearing-off” effect (off periods), in which the medication ceases to be effective at preventing symptoms, and levodopa-induced dyskinesia (LID), a condition in which patients start having involuntary muscle movements.
Requip, marketed by GlaxoSmithKline (GSK), is a dopamine agonist — a substance that has similar properties to dopamine and can mimic some of its effects in the brain — that also has been approved to treat Parkinson’s motor symptoms.
The medication often is prescribed alongside levodopa to extend its effect and reduce the duration of off periods, and is currently available in the form of immediate and extended-release tablets.
“In addition to immediate- and extended-release tablets, a once-daily patch containing ropinirole hydrochloride was recently developed in Japan as a new transdermal formulation,” researchers wrote.
According to the researchers, the new transdermal formulation — in which the medication is slowly absorbed through the skin — being developed by Hisamitsu Pharmaceutical has the potential to improve treatment adherence, since it could provide patients who have problems swallowing and eating with a safer and easier-to-administer option.
Hisamitsu Pharmaceutical researchers conducted a Phase 3 trial (JPRN-JapicCTI-152870) to investigate if the the new skin patch formulation of Requip was as effective and safe as its original extended-release tablet formulation, and if it maintained its superiority over a placebo at reducing motor symptoms of Parkinson’s.
A total of 587 patients with advanced Parkinson’s were assigned randomly to be treated with either the Requip patch (up to 64 mg), the Requip oral extended-release tablet (up to 16 mg), or a placebo, all given once a day alongside levodopa.
The study’s main goal was to assess changes in patients’ motor function, based on the Unified Parkinson’s Disease Rating Scale (UPDRS) Part III scores, from the beginning of the study (baseline) to week 16.
From the 587 patients randomized, 159 were excluded for not complying with the study’s randomization protocol, yielding a total of 428 participants who were included in the final analyses.
Findings revealed that patients receiving the skin patch had a mean reduction (lessening of motor symptoms) of 9.8 points in their UPDRS Part III total score, while those receiving the placebo experienced only a mean reduction of 4.3 points.
“The difference between the ropinirole patch and placebo groups was –5.4, demonstrating superiority of the patch over placebo,” the researchers wrote.
The difference in UPDRS Part III total scores between patients receiving the skin patch or the extended-release tablet was only 0.3 points, suggesting the new transdermal formulation was not inferior to Requip’s currently approved oral extended-release formulation.
Safety assessments revealed that most side effects observed in patients from all treatment groups were only mild or moderate in severity. No serious safety concerns were identified.
“The present study demonstrated the superiority of ropinirole patch over placebo with regard to the decrease of the UPDRS Part III total score, as well as non inferiority of the patch to ropinirole tablets that are currently marketed world-wide,” the researchers wrote.
The team also emphasized the new skin patch may give patients the option to “choose a favorable formulation to meet [their] own unmet medical needs, which is expected to contribute to the improved adherence.”