Efficacy of citicoline as an add-on therapy in Parkinson's disease: a randomized, double-blind trial

Background: Citicoline is a promising therapeutic option for improving both motor and non-motor symptoms in Parkinson's disease (PD) beyond levodopa and other standard dopaminergic treatments. Objectives: The CITIPARK study evaluated the efficacy and safety of citicoline in improving clinical outcomes and quality of life (QOL) in PD patients on dopaminergic therapies. Methods: The randomized, double-blind, multicenter trial compared citicoline (1000 mg/day intramuscular, two six-week cycles) with placebo for 24 weeks in PD under stable medications. The primary endpoint was change in Movement Disorder Society–Unified PD Rating Scale (MDS-UPDRS) total score; secondary endpoints included motor and non-motor subscores, QOL, clinical global impression (CGI) and safety. Results: The study enrolled 485 participants, randomizing 474 (citicoline: 303; placebo: 171). Citicoline significantly increased the likelihood of achieving a minimal clinically important difference compared with placebo (OR 2.06, 95% CI 1.06–3.99; P = 0.031) on the MDS-UDPRS total score in the modified intention-to-treat population. Among secondary outcomes, the citicoline group showed greater improvement in motor function (MDS-UPDRS III -2.97 vs −0.13; p = 0.009) and a greater improvement on CGI -II and CGI-III (3.26 vs 3.59; p = 0.021 and 9.30 vs 10.38; p = 0.018, respectively). AEs occurred in 22.1% and 27.1% of the citicoline and placebo groups, respectively. Conclusions: Citicoline was well tolerated and associated with motor benefits compared with placebo in a highly compliant population. The results suggest a role of citicoline as a safe and possibly effective supportive therapy in PD treated with concomitant dopaminergic agents.