Motor function and treatment satisfaction in adult patients with 5q-spinal muscular atrophy treated with risdiplam: real-world experience from a single neuromuscular center in Germany

Abstract Background To date, there are only two previous reports on motor function during risdiplam therapy in adult patients with spinal muscular atrophy (SMA) in a real-world setting, each comprising six patients with SMA type 2. We aimed to describe the experience of a single neuromuscular center in Germany in treating adult SMA patients with risdiplam and to analyze motor function and treatment satisfaction during a follow-up period up to 20 months. Methods Fourteen patients with type 2 or 3 SMA (seven with SMA type 2, six with SMA type 3; age range: 18–51) were included. The Revised Upper Limb Module (RULM) and the Hammersmith Functional Motor Scale Expanded (HFMSE) were recorded at baseline and at follow-up (month 4, 8, 12, 16, 20). Treatment adverse events were collected at every follow-up visit. Patients’ treatment satisfaction was assessed by the Treatment Satisfaction Questionnaire for Medication (TSQM). Results No significant differences were detected between mean HFMSE and RULM scores obtained at baseline and during risdiplam treatment (p > 0.05). Based on the HFMSE score, no patients had clinically meaningful improvement. Twelve remained stable (92.3%), two showed transient clinically meaningful deterioration (15.4%) and one experienced lasting clinically meaningful deterioration (7.7%). Based on the RULM scores, seven patients were either stable or demonstrated clinically meaningful improvement (53.8%) and six showed clinically meaningful deterioration (46.2%). There was no treatment withdrawal during the follow-up. The most common adverse events were skin rash/increased skin sensitivity to sunlight (n = 3), diarrhea (n = 3), aphthous ulcer (n = 3) and abdominal pain (n = 2). Most patients stated to be at least “satisfied” with the medication. Conclusions Risdiplam was well tolerated. Half of the patients remained stable or improved after risdiplam initiation. Larger and multicentric studies are needed to better understand the long-term effects of risdiplam in adult SMA.