Safety and efficacy of levodopa-carbidopa intestinal gel: results from an open-label extension study in Japanese, Korean and Taiwanese patients with advanced Parkinson’s disease

OBJECTIVES: Levodopa-carbidopa intestinal gel (LCIG) was developed to reduce motor complications in Parkinson’s disease (PD) caused by pulsatile levodopa plasma concentrations following oral levodopa administration. Dyskinesia and ‘wearing off’ symptoms can vary between Asian and Caucasian patients with PD, thus highlighting the importance of assessing the effectiveness of LCIG in an Asian population. Efficacy and safety of LCIG were previously assessed in a 12-week open-label study; we report the efficacy and safety of at least 52 weeks of LCIG treatment in Japanese, Taiwanese, and Korean patients with advanced PD in the ongoing extension study. METHODS: In this interim analysis of a phase III, open-label, multicenter extension study in Japan, South Korea, and Taiwan [ClinicalTrials.gov identifier: NCT02082249/JapiCTI-142482], the mean change from baseline to final visit in ‘off’ time, as reported in the PD symptom diary, was normalized to a 16-h waking day. Changes in Parkinson’s Disease Questionnaire-39 (PDQ-39) summary index and domains scores were also analyzed. Adverse events (AEs) were recorded. RESULTS: Of the 28 patients enrolled (21 Japanese, 3 Taiwanese, 4 Korean), 27 completed at least 52 total weeks of treatment, and 25 patients were continuing in the study at data cutoff. The mean [standard deviation (SD)] ‘off’ time was significantly reduced by 4.6 (3.1) h/day (p < 0.001, n = 28). Patients experienced significant improvements in quality of life, as recorded by the mean change from baseline in PDQ-39 summary index (p < 0.001). All patients had at least one AE; three patients (11%) discontinued due to an AE. There were two deaths (sepsis and drowning), both of which the investigator considered unrelated to LCIG treatment. CONCLUSIONS: These data suggest that LCIG treatment is efficacious, safe, and well tolerated in Japanese, Taiwanese, and Korean patients with advanced PD, thus confirming the consistency of LCIG treatment in patients with advanced PD.