Rotigotine in Combination with the MAO-B Inhibitor Selegiline in Early Parkinson’s Disease: A Post Hoc Analysis

BACKGROUND Monoamine oxidase B (MAO-B) inhibitors and dopamine receptor agonists are common first-line treatment options in early Parkinson's disease (PD). OBJECTIVE To evaluate the efficacy and safety of rotigotine transdermal patch as an add-on therapy to an MAO-B inhibitor in patients with early-PD. METHODS In two Phase III, randomized, double-blind, placebo-controlled studies in early-PD (SP512, SP513), patients were randomized to rotigotine (titrated to optimal dose ≤8 mg/24 h) or placebo, and maintained for 24 (SP512) or 33 (SP513) weeks. Post hoc analyses were performed on pooled data for patients receiving an MAO-B inhibitor (selegiline) at a stable dose at randomization and throughout the studies, with groups defined as "Selegiline+Rotigotine" and "Selegiline+Placebo". Outcome measures included change from baseline in Unified Parkinson's Disease Rating Scale (UPDRS) II (activities of daily living), III (motor), UPDRS II+III and responders (patients achieving ≥20%, ≥25% or ≥30% decrease in UPDRS II+III). As post hoc analyses, p-values are exploratory. RESULTS 130 patients were evaluable for efficacy analyses ("Selegiline+Rotigotine": 84, "Selegiline+Placebo": 46). Combined treatment with rotigotine and selegiline improved UPDRS III and UPDRS II+III scores versus selegiline alone (LS-mean [95% CI] treatment difference for UPDRS III: -4.89 [-7.87 to -1.91], p = 0.0015; for UPDRS II+III: -5.76 [-9.71 to -1.82], p = 0.0045). Higher proportion of patients in the "Selegiline+Rotigotine" group were classified as ≥20%, ≥25% or ≥30% responders (all p < 0.001). Combined treatment appeared more effective in patients aged ≤65 years versus > 65 years (although patient numbers in the subgroups were low). Adverse event profile was consistent with the known safety profile of rotigotine. CONCLUSIONS In these post hoc analyses, adjunctive treatment with rotigotine in patients already receiving an MAO-B inhibitor improved UPDRS II+III score; this appeared to be largely driven by improvements in the motor aspects of PD.