Clinical Use Patterns and Patient-Reported Experience with Inhaled Levodopa in Routine Practice: A Two-Center Study

Background/Objectives: On-demand therapies are crucial to manage OFF episodes in Parkinson's disease (PD). Inhaled levodopa is a rapid and non-invasive treatment option, but data on its real-world use and patient-reported experience remain limited. This study characterized clinical use patterns and patient experience with inhaled levodopa in routine clinical practice. Methods: We conducted a multicenter, cross-sectional, observational study including patients with PD treated with inhaled levodopa in two Spanish centers. Data on treatment use, patient-reported clinical response, and satisfaction were collected during a single study visit using study-specific questionnaires. Results: Thirty-five patients were included (mean age 70.6 years; 51.4% women). Most patients used inhaled levodopa once daily (51.4%), with administration patterns varying between on-demand (51.4%), fixed (31.4%), and combined regimens (17.1%). According to routine clinical assessments, 80.0% of patients reported a clinical response to inhaled levodopa, with a mean time to onset of 17.7 min and a mean duration of effect of 122.1 min. The perceived response was rated as moderate or marked in 62.8% of patients and was reported to last until the next scheduled oral levodopa dose in 45.7% of patients. Participants highlighted symptom improvement, ease of identifying the appropriate timing of administration, and a favorable perception of treatment safety. Conclusions: In routine clinical practice, inhaled levodopa was associated with a high patient-reported clinical response and favorable treatment experience across diverse patient profiles. These findings provide relevant insights into the real-world use of inhaled levodopa as an on-demand therapy for OFF episodes in PD. Given the exploratory nature of this study, confirmation in larger prospective studies using validated instruments and objective clinical measures is warranted.