A new therapeutic strategy with istradefylline for postural deformities in Parkinson's disease.

Postural deformities are common in Parkinson's disease (PD) patients. Several treatment options have been reported, but responses to these treatments appear unpredictable. Istradefylline is a novel drug for PD. Cases of PD patients whose postural deformities were improved after withdrawal of dopamine agonists and initiation of istradefylline are presented. Four consecutive patients with postural deformities including antecollis, Pisa syndrome, and camptocormia were recruited and treated with istradefylline in combination with withdrawal of dopamine agonists, which are possible causes of postural deformities. The dopamine agonists were discontinued an average of 26 months after the development of the postural deformities, and istradefylline was initiated an average of 1.3 months after dopamine agonist withdrawal. Three patients with preserved paraspinal muscle volume showed good responses to the treatment regimen at least two months after dopamine agonist withdrawal. Postural deformities caused by dopamine agonists generally improve less than two weeks after dopamine agonist withdrawal. Given the response time in the present study, the response was unlikely to be caused solely by dopamine agonist withdrawal. Istradefylline can be a potential therapeutic option; however, appropriate selection of patients for treatment with istradefylline is warranted.