BOSTON – presented at the 2023 annual meeting of the American Academy of Neurology.
When compared with optimized oral immediate-release medication, the delivery system, called ND0612 (NeuroDerm, Rehovot, Israel), improved ON time without troublesome dyskinesias while improving symptoms according to ratings from both patients and clinicians, according to Alberto J. Espay, MD, professor of neurology and director of the Gardner Family Center for Parkinson’s Disease and Movement Disorders, University of Cincinnati.
Ted Bosworth/MDedge News
Dr. Alberto J. Espay
The new delivery system addresses the challenge of reducing the variability in levodopa plasma concentrations, a major factor in motor fluctuations and diminishing benefit from orally administered drug, according to Dr. Espay. He said that continuous infusion strategies have long been sought as a method to preserve levodopa efficacy.
BouNDless findings
There were two phases to this multinational trial, called BouNDless. In the first, an open-label run-in phase, 381 patients with Parkinson’s disease were dose titrated for optimization of oral immediate-release levodopa and carbidopa. They were then optimized for the same drugs delivered with ND0612. The study was conducted over 12 weeks; 122 patients left the study after this phase due to adverse events, lack of efficacy, or withdrawal of consent.
In the second phase, the 259 remaining patients were randomized to the continuous infusion arm or to immediate release oral therapy. In this double-blind, double-dummy phase, those randomized to the ND0612 infusion also received oral placebos. Those randomized to oral therapy received a placebo infusion. Efficacy and safety were assessed at the end of 12 weeks.
At the end of phase 1, the ON time increased by about 3 hours when levodopa-carbidopa dosing was optimized on either delivery method. Dr. Espay attributed the improvement to the value of optimized dosing even in patients with relatively advanced disease.
However, for the purposes of the double-blind comparison, this improvement in ON time provided a new baseline for comparison of the two delivery methods. This is important for interpreting the primary result, which was a 1.72-hour difference in ON time at the end of the study. The difference was created when ON time was maintained with ND0612 continuous drug delivery but eroded in the group randomized to oral immediate-release treatment.
Several secondary endpoints supported the greater efficacy of continuous subcutaneous delivery. These included lower OFF time (0.50 vs. 1.90 hours), less accumulation of disability on the United Parkinson’s Disease Rating Scale part II-M-EDL (-0.30 vs. +2.75 points), and greater improvement on the Patient Global Impression of Change (+0.31 vs. +0.70 points), and the Clinical Global Impression of change (+0.31 vs. +0.77 points). The differences were highly statistically significant (all P < .0001).
The patients participating in the double-blind phase of the study were similar with a mean age of 63.5 years in both groups and time since Parkinson’s disease diagnosis (> 9 years). The median ON time without troublesome dyskinesias was about 12 hours at baseline in both groups and the median OFF time was about 3.5 hours.
The higher rate of treatment-related adverse events in the ND0612 group (67.2% vs. 52.7%) was largely explained by the greater rate of infusion site reactions (57.0% vs. 42.7%). The rates of severe reactions in the two groups were the same (0.8%), but both mild (43.8% vs. 36.6%) and moderate (12.5% vs. 5.3%) reactions occurred more commonly in the group receiving active therapy.
“Infusion reactions are the Achilles heel of all subcutaneous therapies,” acknowledged Dr. Espay, who expects other infusion systems in development to share this risk. He suggested that the clinical impact can be attenuated to some degree by rotating infusion sites.