Safety and Efficacy of IPX203 in Parkinson's Disease: The RISE-PD Open-Label Extension Study

BackgroundIPX203 is a novel oral extended-release formulation of carbidopa/levodopa (CD/LD) developed to address the short half-life of immediate-release CD/LD. In the phase 3 RISE-PD trial, IPX203 significantly improved "Good On" time in patients with Parkinson's disease compared with immediate-release CD/LD.ObjectivesTo evaluate the safety and efficacy of IPX203 in an open-label extension of the pivotal phase 3 study.MethodsThis 9-month extension enrolled patients who completed the randomized, double-blind trial. Key efficacy endpoints included Movement Disorder Society-Unified Parkinson's Disease Rating Scale and Patient and Clinical Global Impression scores. Adverse events (AEs) were recorded.ResultsImprovements in efficacy were maintained and dosing frequency and total daily dose remained stable through the trial. A total of 52.7% of patients experienced >= 1 treatment-emergent AE, mostly mild or moderate and occurred within the first 90 days of treatment.ConclusionsIn this phase 3 open-label extension, IPX203 exhibited a favorable safety and tolerability profile and sustained efficacy of comparable magnitude to the end of the double-blind study. (c) 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.