Promising Results for CPL'36 in Reducing Levodopa-Induced Dyskinesia in Parkinson’s Patients

CPL’36, an oral small molecule developed by Celon Pharma, may help alleviate levodopa-induced dyskinesia (uncontrolled movements) in Parkinson’s disease patients within one week. This finding comes from a Phase 2 clinical trial (NCT05297201) involving 105 adults with Parkinson’s. The trial is assessing the drug’s effectiveness compared to a placebo, its safety, and how it is processed in the body. CPL’36 is a PDE10A inhibitor, which may help regulate nerve signaling in the brain, improving motor function. In animal studies, it reduced motor symptoms and levodopa-induced dyskinesia without diminishing the benefits of levodopa, indicating it may be used alongside this main treatment for Parkinson’s. The Phase 2 trial tested two doses of CPL’36 (20 mg and 40 mg) against a placebo, with the primary goal of reducing dyskinesia. After four weeks, both doses showed significant improvements in dyskinesia, with patients on 20 mg improving by 12.3 points and those on 40 mg improving by 13.6 points on the Unified Dyskinesia Rating Scale. Improvements in other motor symptoms were seen as early as one week. CPL’36 was generally well-tolerated, with drowsiness being the most common side effect. Severe side effects were more frequent in the placebo group. A small percentage of patients discontinued treatment due to side effects, and one patient experienced atrial fibrillation. Celon Pharma's CEO, Maciej Wieczorek, expressed confidence that CPL’36 could significantly improve treatment options for patients with levodopa-induced dyskinesia, who currently have limited treatment choices.