Questions about the continuous subcutaneous levodopa–carbidopa infusion study

The BouNDless trial tested a continuous under-the-skin infusion of a drug combination (levodopa–carbidopa) in patients with Parkinson's disease who experience motor fluctuations. The study, led by Alberto J. Espay and colleagues, found that this infusion improved patients' movement control by increasing the time they experienced good motor function without troublesome involuntary movements (dyskinesia) and by reducing the time they had poor motor function ("off" time). However, more patients in the group taking the standard oral form of the drug were also taking amantadine, a medication known to reduce dyskinesia. This difference in amantadine use might have affected the comparison of dyskinesia severity between the two groups, potentially hiding true differences and impacting the study's results. Addressing this could make the trial's findings more accurate. Additionally, the positive outcomes seen with continuous drug infusion like ND0612 and extended-release capsules like ADS-5102 have encouraged us to consider future research into adaptive, on-demand drug delivery systems. These systems could adjust based on drug levels in the blood, potentially offering even better control of movement and fewer side effects for patients with Parkinson's disease. We have no conflicts of interest to declare.