AFQ056 Treatment of Levodopa-Induced Dyskinesias: Results of 2 Randomized Controlled Trials

University of Tübingen, Hertie-Institute of Clinical Brain Research and German Center for Neurodegenerative Diseases, Tübingen, Germany.
Movement Disorders (Impact Factor: 5.68). 06/2011; 26(7):1243-50. DOI: 10.1002/mds.23616
Source: PubMed


Study objectives were to assess the efficacy, safety, and tolerability of AFQ056 in Parkinson's disease patients with levodopa-induced dyskinesia. Two randomized, double-blind, placebo-controlled, parallel-group, in-patient studies for Parkinson's disease patients with moderate to severe levodopa-induced dyskinesia (study 1) and severe levodopa-induced dyskinesia (study 2) on stable dopaminergic therapy were performed. Patients received 25-150 mg AFQ056 or placebo twice daily for 16 days (both studies). Study 2 included a 4-day down-titration. Primary outcomes were the Lang-Fahn Activities of Daily Living Dyskinesia Scale (study 1), the modified Abnormal Involuntary Movement Scale (study 2), and the Unified Parkinson's Disease Rating Scale-part III (both studies). Secondary outcomes included the Unified Parkinson's Disease Rating Scale-part IV items 32-33. The primary analysis was change from baseline to day 16 on all outcomes. Treatment differences were assessed. Fifteen patients were randomized to AFQ056 and 16 to placebo in study 1; 14 patients were randomized to each group in study 2. AFQ056-treated patients showed significant improvements in dyskinesias on day 16 versus placebo (eg, Lang-Fahn Activities of Daily Living Dyskinesia Scale, P = .021 [study 1]; modified Abnormal Involuntary Movement Scale, P = .032 [study 2]). No significant changes were seen from baseline on day 16 on the Unified Parkinson's Disease Rating Scale-part III in either study. Adverse events were reported in both studies, including dizziness. Serious adverse events (most commonly worsening of dyskinesias, apparently associated with stopping treatment) were reported by 4 AFQ056-treated patients in study 1, and 3 patients (2 AFQ056-treated patient and 1 in the placebo group) in study 2. AFQ056 showed a clinically relevant and significant antidyskinetic effect without changing the antiparkinsonian effects of dopaminergic therapy. © 2011 Movement Disorder Society.

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    • "Acamprosate mGluR5 antagonist Human trials e.g., Erickson et al., 2011 Memantine mGluR5 antagonist Human trials e.g., Erickson et al., 2009 AFQ056 mGluR5 antagonist Human trials e.g., Berg et al., 2011 Fenobam mGluR5 antagonist Human trials e.g., Berry-Kravis et al., 2009 Frontiers in Neuroscience | 3 March 2015 antagonists produce side effects in humans that include mem - ory impairment , psychotic episodes , and strokes ( Swanson et al. , 2005 ) . "
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