Efficacy and safety of safinamide in Parkinson's disease patients with motor fluctuations without levodopa dosage escalation over 18 weeks: KEEP study

This multicentre, prospective, single-arm study evaluated safinamide as add-on therapy to levodopa in Korean patients with Parkinson's disease (PD) with motor fluctuations with ≥ 1.5 h of "off" time daily, who took levodopa ≥ 3 times/day (n = 199). Baseline levodopa and dopamine agonist doses were maintained without escalation during the 18-week treatment period. Participants received safinamide 50 mg/day for 2 weeks and 100 mg/day thereafter. PD diaries and questionnaires (Parkinson's Disease Questionnaire, PDQ-39; Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale, MDS-UPDRS part 3 and part 4; King's Parkinson's Disease Pain Scale, KPPS; Mini-Mental State Examination, MMSE) were assessed at baseline and at week 18. Treatment-emergent adverse events (TEAEs) were recorded. Mean disease duration was 6.6 years, and mean levodopa equivalent daily dose was 721.1 mg/day. At week 18, significant improvements from baseline were seen for the co-primary endpoints, mean daily "off" time (- 1.3 ± 2.4 h, p