Continuous Apomorphine Infusion in Multiple System Atrophy Real‐World Insights From a French Nationwide Retrospective Cohort

BACKGROUND: Continuous subcutaneous apomorphine infusion (CSAI) is effective in Parkinson's disease but has not been evaluated in multiple system atrophy (MSA). OBJECTIVE: To assess the 6-month efficacy and tolerability of CSAI in MSA patients. METHODS: French multicenter retrospective registry-based analysis of CSAI use in MSA. The primary outcome was the 6-month clinical response using the Clinical Global Impression Improvement (CGI-I) scale. Secondary outcomes included tolerability, indications, infusion parameters, and treatment course. RESULTS: Fifty patients were included; 94% had MSA-P. All had motor fluctuations and 88% showed a clinically meaningful dopaminergic response. CSAI was initiated for motor symptoms (100%) or pain (54%). At 6 months, most patients improved (36% "much," 54% "minimally"), mainly due to reduced motor fluctuations. Only 8% discontinued CSAI. Tolerability was rated good/excellent in 74%; 20% reported somnolence and/or orthostatic hypotension. CONCLUSION: In selected MSA patients with partial dopaminergic responsiveness and motor fluctuations, CSAI provided short-term clinical benefit with acceptable tolerability.