BACKGROUND: Advanced Parkinson’s disease (APD) severely impacts the quality of life (QoL) for both patients and their caregiver and is associated with high health care and societal costs. The treatment options for those patients are limited. Duodenal levodopa infusion (DLI), an orphan drug, has shown to restore symptom control and to improve QoL substantially for both patients and their carers.   OBJECTIVES: To evaluate the cost-utility of DLI versus standard treatment (including oral treatment and subcutaneous dopamine agonists) in patients with advanced PD in Sweden. METHODS: A stochastic Markov-based simulation model was developed. Health was described by 12 health states reflecting 4 categories of “OFF” time and 3 severity stages as measured by the Hoehn & Yahr scale. The clinical effect for both treatment arms was derived from published clinical trials; costs and QoL utilities were taken from an interim analysis of the ongoing DAPHNE study. The base case simulated 5 years with costs/effects discounted by 3%. The societal perspective was adopted.   RESULTS: The model estimated an improvement from 0.68 to 1.30 QALYs and a cost increase from 1,410,643 (€147,108) to SEK 1,674,295 (€174,603) for DLI versus standard treatment, leading to an incremental cost-effectiveness ratio (ICER) of around SEK 420,000 (€43,800) per QALY gained. The ICER for nearly 90% of the cohorts fell below SEK 655,000 (€68,306), the willingness-to-pay threshold often cited for Sweden [1]. Sensitivity analysis was associated with ICERs ranging up to SEK 900,000 (€93,856) per QALY gained. CONCLUSIONS: Due to the data limitations, HE modeling in the orphan drug setting is challenging. Analysis could be performed as requested by Sweden’s Dental and Pharmaceutical Benefits Agency (TLV), however, providing evidence that health benefits can provide good value for money even for an orphan population. DLI received a positive reimbursement recommendation by the TLV. [1] Persson U, Hjelmgren J (2003).