Initiating foslevodopa infusion in Parkinson disease: a pragmatic study

Background: Subcutaneous foslevodopa (fLD) infusions are a new therapeutic option for treating complicated Parkinson's disease (PD). Objectives: To assess the initial period of fLD infusion as replacement of oral medications in PD. Methods: PD patients started infusion treatment according to recommended practice. Efficacy was assessed using the MDS-UPDRS motor examination and motor complications scores in the ON condition at baseline and after 20 weeks. Safety and fLD doses were assessed on a weekly basis. The 20-week observation period was compared to baseline. Results: On week 20 the MDS-UPDRS motor examination score was unchanged, whereas the motor complications score was improved, indicating increased ON time without troublesome dyskinesias and reduced OFF time. The initial fLD dosage was gradually increased in all patients, by 37 % on week 20. Treatment optimization was achieved at a median of 12 weeks; patients with higher body mass index required a longer titration period. The levodopa equivalent daily dose of fLD on week 20 was 0.57mg. Adverse events occurred in 87 % of patients, primarily consisting of skin reactions at the infusion sites that occasionally required treatment. Discussion: fLD infusion reduced motor fluctuations while maintaining stable ON motor performance. The infusion dose was progressively increased in the initial treatment period. The time needed for treatment stabilization was longer than previously reported and delayed in patients with higher body mass index. The treatment was generally well tolerated, neuropsychiatric effects were more common than previously reported.