Objective: In patch-based transdermal drug delivery, adhesiveness is critical for safe and effective treatment, especially in Parkinson's disease (PD) where excessive sweating is common. This study compared the adhesiveness of two transdermal patch formulations of rotigotine (improved room temperature-stable [PR2.3.1/Treatment A] and intermediate cold storage product [PR2.1.1/Treatment B]), using the largest patch size (40 cm2).
Methods: PD0018 (NCT02230904) was a multicenter, randomized, double-blind, crossover study. PD patients received Treatments A and B in randomized order for 2 days each. Patch adhesiveness was measured immediately after patch application and 24 hours thereafter (before removal). Primary variable: change in average investigator-rated adhesiveness score between treatments, per modified European Medicines Agency scale (EMA/CHMP/QWP/911254/2011, 2012).
Results: Fifty-seven patients were randomized; 56 patients completed the study. Five patients were excluded from analysis for accidental unblinding. Treatment A had better average adhesiveness score (mean ± SD Treatment A - Treatment B: 1.115 ± 1.635). A higher percentage of patients on both days had patch adhesiveness ≥95% at 24 hours for Treatment A (first day: 65.4%, second day: 71.2%) vs. Treatment B (46.2%, 36.5%), and were satisfied with patch adhesiveness of Treatment A (first day: 75.0%, second day: 73.1%) vs. Treatment B (65.4%, 59.6%). Average patch-wear duration was similar between formulations (23.761 hours vs. 23.495 hours per patch). Both formulations were well tolerated with no new safety observations.
Conclusion: Results indicated greater adhesiveness for the improved room temperature-stable formulation (PR2.3.1) vs. intermediate cold storage product (PR2.1.1) using the largest patch-size, with comparable safety and skin tolerability.
Keywords: Adhesiveness; Parkinson’s disease; bioequivalence; formulation; patch; rotigotine; transdermal.