Could istradefylline be a treatment option for postural abnormalities in mid-stage Parkinson's disease?

Baseground: Postural abnormalities are refractory complications observed in mid- to late-stage Parkinson's disease (PD). Methods: We analyzed the effects of istradefylline, a selective adenosine A2A receptor antagonist, on posture in 21 levodopa-treated PD patients from the subanalysis of a three-month open-label study. Results: The subitem score of posture (3.13) on the Movement Disorder Society revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) part III significantly improved following istradefylline treatment (baseline, 1.3 +/- 1.0 points vs 3 months, 0.9 +/- 0.9 points; p < 0.05). Among 18 patients who had postural abnormalities at baseline, defined as 1 point or greater on MDS-UPDRS part III subitem 3.13, posture improved in 9 (50%) and was unchanged in 9 (50%) patients after istradefylline treatment. Improved and unchanged groups did not show differences in baseline characteristics, except for tendency for a higher rate of Hoehn and Yahr stage IV and V (Off state) observed in the improved group. Changes in scores of posture (3.13) did not correlate with those of other MDS-UPDRS part III items, PD Questionnaire-8, PD Sleep Scale-2 and Epworth Sleepiness Scale. Conclusion: Based on our preliminary findings, istradefylline could be an effective treatment option for postural abnormalities in mid-stage PD patients.