Celon Pharma S.A.

Legal Proceedings Report • Mar 4, 2025

PhaseII top - line results for CPL' 36, a PDE10a inhibitor in the treatmentof Dyskinesia in Parkinson's diseaseLegalbasis Art. 17 section 1 MAR - confidential information.Inreference to current report 17/2024 regarding positive results of thePhase II clinical trial ona drug based on CPL'36, an innovative PDE10A inhibitor, in the treatmentof schizophrenia, in which the Company informed about the simultaneousongoing Phase II clinical trial of the use of this compound in patientswith dyskinesia in Parkinson's disease, theManagement Board of Celon Pharma S.A. (the"Company") announcespositive Phase II results of this study.Thiswas multinational,multicenter, randomized, placebo controlled study in group of 105 adultpatients with dyskinesia in Parkinson's disease. CPL'36 was administeredorally in two doses - 20mg and 40 mg, and compared with placebo (1:1:1)once daily for a period of 4 weeks. The baseline score of UDysRS(Unified Dyskinesia Rating Scale) forrandomized patients wasapproximately 45 points, indicatingthey were moderately severe to severely ill.Atweek 4, the improvement in UDysRS totalscore (designated as primary endpoint) at the dose 20 mg was 12,30units (LS Mean difference from placebo, p<0,001, Cohen's d: 0,90) andimprovement at the dose 40 mg was 13,58 units (LS Mean difference fromplacebo, p<0,001, Cohen's d: 1,00).TheCPL'36 demonstrated improvement in most secondary endpoints, including UDysRSobjective subcale, in which the improvement in both active groups wasstatistically significant from Day 7 of the treatment phase, andafterwords.CPL'36was well tolerated. There were only few adverse events with severeintensity (8,8% in placebo group, 0% in 20 mg dose and 5,7% in 40 mgdose). Related treatment emergent adverse events leading todiscontinuation of study medication were recorded in 2,9% in placebogroup, 11,1% in 20 mg dose and 8,6% in 40 mg dose. There were no deaths.OneSerious Adverse Event was reported in 40 mg group, described as atrialfibrillation with moderate intensity. The most common adverse eventreported in both active groups was somnolence with intensity from mildto moderate.Thestudy met all endpoints, exceeding significantly earlier Company'smedical assumptions. It demonstrated robust and consistent efficacyacross all different scales suggesting positive effect of CPL'36 in thetreatment of dyskinesia in Parkinson's disease. The effect size waslarge.Thisis the first clinical study demonstrating robust efficacyofPDE10A inhibition in the treatment of patients suffering from dyskinesiain Parkinson's disease with positive primary and secondary endpointsreadouts. In the Company opinion, its results should be seen asbreakthrough milestone in Parkinson disease pharmacotherapy.