Celon Pharma has announced compelling Phase 2 clinical trial results for CPL'36, their novel PDE10A inhibitor developed for treating Levodopa-Induced Dyskinesia (LID) in Parkinson's disease patients. The oral, once-daily medication demonstrated robust efficacy and met its primary endpoint with statistically significant improvements.
Clinical Trial Results and Efficacy
The multinational, multicenter study enrolled 105 adult patients with moderate-severe to severe LID, characterized by baseline UDysRS (Unified Dyskinesia Rating Scale) total scores of approximately 45. Patients received either 20mg or 40mg doses of CPL'36 or placebo in a 1:1:1 ratio over four weeks.
The results showed remarkable improvements in the primary endpoint. The 20mg dose group achieved a 12.30-unit reduction in UDysRS total score compared to placebo (p<0.001, Cohen's d: 0.90), while the 40mg dose group showed a 13.58-unit improvement (p<0.001, Cohen's d: 1.00). Notably, positive effects were observed as early as Day 7 in the UDysRS objective subscale.
Safety and Tolerability Profile
CPL'36 demonstrated a favorable safety profile across both dosing arms. Severe adverse events were more prevalent in the placebo group (8.8%) compared to the treatment arms (0% in 20mg, 5.7% in 40mg). Treatment discontinuation rates were 11.1% and 8.6% for the 20mg and 40mg doses respectively, with mild to moderate somnolence being the most commonly reported side effect.
Only one serious adverse event - moderate atrial fibrillation - was reported in the 40mg group, with no deaths occurring during the trial.
Mechanism of Action and Clinical Significance
"CPL'36 has a unique pharmacodynamic profile, characterized by rapid enzyme dissociation, which distinguishes it from other PDE10A inhibitors," explained Joanna Sierzputowska-Prarat, Main Clinical Neuropsychiatry Lead at Celon Pharma. This distinctive mechanism may be key to the positive clinical outcomes observed.
Dr. Maciej Wieczorek, CEO of Celon Pharma, emphasized the potential impact: "The results are unequivocally positive, clinically meaningful, and statistically significant. We believe that CPL'36 has potential to significantly contribute to the expansion and advancement of the global market for Parkinson's disease pharmacotherapy, and to provide sizeable clinical benefits to LID patients who are underserved by current treatments."
Future Development Prospects
The success in this LID trial follows positive Phase 2 results for CPL'36 in schizophrenia reported in July 2024, suggesting broader therapeutic potential. The compound's demonstrated efficacy and safety profile position it as a promising candidate for addressing the significant unmet need in managing Levodopa-induced dyskinesia in Parkinson's disease patients.
