Ultragenyx Provides Update on Stage 1 Cohorts in Pivotal Phase 1/2/3 Cyprus2+ Study Evaluating UX701 Gene Therapy for the Treatment of Wilson Disease

Core Insights - Ultragenyx Pharmaceutical Inc. reported positive results from the Phase 1/2/3 Cyprus2+ study of its UX701 gene therapy for Wilson disease, showing meaningful clinical activity and improvements in copper metabolism [1][2][3] Group 1: Study Results - In Stage 1, 15 patients were enrolled in three dosing cohorts, with six patients completely tapering off standard-of-care treatment, and a seventh patient beginning to taper [2][4] - Non-ceruloplasmin bound copper (NCC) levels stabilized to normal in patients who tapered off standard-of-care, indicating improved copper metabolism [2] - UX701 was well tolerated with no unexpected treatment-related adverse events reported as of the data cut-off [2] Group 2: Future Plans - The company plans to enroll an additional cohort at a moderately increased dose and with an optimized immunomodulation regimen to enhance the therapy's efficacy [1][3] - A fourth dosing cohort will be added, and all patients in Stage 1 will be evaluated over 52 weeks [4] Group 3: Study Design - The study is designed in three stages, with Stage 1 focusing on safety and efficacy across multiple dose levels of UX701 [4][5] - In Stage 2, a new cohort will be randomized to receive either the selected dose of UX701 or a placebo, with primary efficacy endpoints including changes in 24-hour urinary copper concentration [5] Group 4: About Wilson Disease - Wilson disease is a rare genetic disorder caused by mutations in the ATP7B gene, leading to copper accumulation in the body and various health issues [6] - The disease affects over 50,000 people in commercially accessible geographies, highlighting a significant unmet medical need [6] Group 5: About UX701 - UX701 is an investigational AAV9 gene therapy designed to deliver stable expression of the ATP7B copper transporter following a single intravenous infusion [7] - It has received Orphan Drug Designation in the U.S. and EU, as well as Fast Track Designation in the U.S. [7] Group 6: About Ultragenyx Pharmaceutical Inc. - Ultragenyx is focused on developing novel therapies for rare and ultrarare genetic diseases, with a diverse portfolio aimed at addressing high unmet medical needs [8] - The company emphasizes time- and cost-efficient drug development to deliver safe and effective therapies urgently [9]