Utilization patterns of Amantadine in Parkinson?s Disease patients enrolled in the French COPARK study

PEREZ LLORET SANTIAGO; DAMIER P; NEGRE-PAGES, L.; OLIVIER RASCOL

Niza

Congreso; 23th International Congress of Parkinson?s Disease and Movement Disorders; 2019

International Parkinson and Movement Disorders Society

Amantadine is the only drug in the market with an adequately demonstrated efficacy for the treatment of L-DOPA-induced dyskinesias (LIDs) in Parkinson?s Disease (PD) patients. It is available worldwide and recently an extended-release formulation has become available in some countries. Notwithstanding, there is no data about its utilization in PD. The objectives of this study were to assess the prevalence of amantadine use, its doses and probable indications, as well as the changes in prescription patterns during the follow-up period. Data from 683 idiopathic, ambulatory, non-demented PD patients enrolled in the French COPARK study were analyzed for this study. Patients were consecutively recruited from movement disorders clinics, hospital-based neurology clinics and private neurology practices at 4 main regions in France. Amantadine was prescribed to 61 (9%) patients, of whom 15 (25%) were on 100 mg/day, 30 (49%) on 200 mg/day and 16 (26%) on 300 mg/day. Amantadine was initiated a median of 84 months after PD diagnosis (25-75 percentiles= 55-153). Median duration of treatment was 16 months (5-61). Patients on amantadine showed a significant and independent difference in the frequency of dyskinesia (OR, 95% CI= 3.72, 1.95-7.08) and in the hallucinations score of the UPDRS 1 (1.57, 1.08-2.29). Among the 401 patients that were assessed in a follow-up visit (median time= 22.7 months), 30 (7%) started amantadine, 5 (1%) increased the dose, 9 (2%) stopped amantadine, 6 (2%) reduced the dose, and 13 (3.2%) did not show any change. Patients that began or increased amantadine (n=35) had more dyskinesias at baseline (7.02, 3.09-15.90) and higher MMSE score at follow-up (1.37, 1.06-1.79). Conversely, patients that stopped or reduced amantadine had undergone surgery more frequently (22.02, 4.24-114.44), without further differences. In this cohort of unselected French PD patients, amantadine use limited, being LIDs its main indication. Patients starting amantadine had less cognitive impairment. Neurosurgery was the main cause of treatment cessation.