Effect of levodopa‐carbidopa intestinal gel on dyskinesia in advanced Parkinson's disease patients

OBJECTIVE: The purpose of this study was to assess the effect of levodopa‐carbidopa intestinal gel (carbidopa‐levodopa enteral suspension) in advanced Parkinson's disease patients with troublesome dyskinesia. METHODS: Post hoc analyses of patient data from a 12‐week, randomized, double‐blind study and a 54‐week open‐label study were performed. Efficacy was assessed in the subgroup of patients defined by ≥1 hour of “on” time with troublesome dyskinesia at baseline as recorded in Parkinson's disease symptom diaries (double blind: n = 11 levodopa‐carbidopa intestinal gel, n = 12 oral levodopa‐carbidopa; open label: n = 144 levodopa‐carbidopa intestinal gel). The changes in “off” time, “on” time with and without troublesome dyskinesia, and the overall safety and tolerability of levodopa‐carbidopa intestinal gel were analyzed. RESULTS: Although not significantly different from oral levodopa treatment (P > .05) in the double‐blind study, levodopa‐carbidopa intestinal gel treatment resulted in a reduction from baseline in “on” time with troublesome dyskinesia (mean [standard deviation] hours: baseline = 3.1 [1.7], change from baseline to final = −1.8 [1.8], P = .014), increase in “on” time without troublesome dyskinesia (baseline = 7.4 [2.2], change = 4.4 [3.6], P = .004), and decrease in “off” time (baseline = 5.5 [1.3], change = −2.7 [2.8], P = .015). Similar trends were found in the open‐label study. An increase in levodopa‐carbidopa intestinal gel dose was not significantly correlated with increased “on” time with troublesome dyskinesia in either study (double blind: r = −.073, P = .842; open label: r = −0.001, P = .992). Adverse events were usually mild to moderate in severity and related to the gastrointestinal procedure. CONCLUSION: Our exploratory analyses suggest that optimizing levodopa delivery with levodopa‐carbidopa intestinal gel may reduce troublesome dyskinesia in advanced Parkinson's disease. © 2016 International Parkinson and Movement Disorder Society