Nikolaus McFarland1, Ramsha Farrukh1, Savanna Mahn1
1Neurology, University of Florida College of Medicine
Objective:
To determine the efficacy and tolerability of amantadine therapy in Progressive supranuclear palsy (PSP).
Background:
PSP is one of the most common atypical parkinson disorders, resulting in progressive disability and early mortality. Although increasingly recognized, including varied phenotypic presentations of PSP, therapeutic options remain significantly limited and fraught with insufficient supporting data on efficacy. There are currently no approved therapies for PSP. Symptomatic drug treatment for PSP typically begins with trial of carbidopa-levodopa, but in most cases levodopa is poorly effective and provides only modest benefit. Multiple alternative medications have been tried in PSP, however, mainly in small studies with limited effects or benefit. Amantadine remains a primary alternative therapy with anecdotal benefit to gait and speech, but lacks evidence and risks adverse effects.
Design/Methods:
We describe a single center retrospective review from 2011 to 2022 of PSP cases treated with amantadine. Both the UF INFORM database and electronic records were queried to identify cases with clinical data, pre and post amantadine treatment with minimum window of 6 months. Data including demographics, dose, and treatment effects, including PSPRS, UPDRS, PSPQol, Beck Depression and Anxiety inventories were collected.
Results:
Of over 350 PSP cases reviewed, 64 were treated with amantadine, and 42 (22 female) with adequate data. Mean age was 70.4 yrs, duration of symptoms 3.84 yrs, and treatment length 8.1 (±2.2) months. 30 participants reported no benefit or worsening of symptoms, whereas 5 indicated improvement, and 7 unclear. Mean change in total PSPRS or axia/gait subscore was not significantly different among these groups. Adverse effects included confusion/hallucinations (6), worsening gait/dizziness (3), and leg edema (1).
Conclusions:
While a small percentage of PSP patients tolerated and reported subjective benefit from amantadine, objectively, amantadine did not improve PSPRS scores and may worsen symptoms or cause adverse effects.