RT Generic T1 The ARCA Registry: A Collaborative Global Platform for Advancing Trial Readiness in Autosomal Recessive Cerebellar Ataxias A1 Traschuetz, Andreas A1 Reich, Selina A1 Adarmes, Astrid D. A1 Anheim, Mathieu A1 Ashrafi, Mahmoud Reza A1 Baets, Jonathan A1 Basak, A. Nazli A1 Bertini, Enrico A1 Brais, Bernard A1 Gagnon, Cynthia A1 Gburek-Augustat, Janina A1 Hanagasi, Hasmet A. A1 Heinzmann, Anna A1 Horvath, Rita A1 de Jonghe, Peter A1 Kamm, Christoph A1 Klivenyi, Peter A1 Klopstock, Thomas A1 Minnerop, Martina A1 Muenchau, Alexander A1 Renaud, Mathilde A1 Roxburgh, Richard H. A1 Santorelli, Filippo M. A1 Schirinzi, Tommaso A1 Sival, Deborah A. A1 Timmann, Dagmar A1 Vielhaber, Stefan A1 Wallner, Michael A1 van de Warrenburg, Bart P. A1 Zanni, Ginevra A1 Zuchner, Stephan A1 Klockgether, Thomas A1 Schuele, Rebecca A1 Schols, Ludger A1 Synofzik, Matthis A1 PREPARE Consortium, K1 ataxia K1 registry K1 network K1 natural history K1 trial readiness K1 Severity AB Autosomal recessive cerebellar ataxias (ARCAs) form an ultrarare yet expanding group of neurodegenerative multisystemic diseases affecting the cerebellum and other neurological or non-neurological systems. With the advent of targeted therapies for ARCAs, disease registries have become a precious source of real-world quantitative and qualitative data complementing knowledge from preclinical studies and clinical trials. Here, we review the ARCA Registry, a global collaborative multicenter platform (>15 countries, >30 sites) with the overarching goal to advance trial readiness in ARCAs. It presents a good clinical practice (GCP)- and general data protection regulation (GDPR)-compliant professional-reported registry for multicenter web-based capture of cross-center standardized longitudinal data. Modular electronic case report forms (eCRFs) with core, extended, and optional datasets allow data capture tailored to the participating site's variable interests and resources. The eCRFs cover all key data elements required by regulatory authorities [European Medicines Agency (EMA)] and the European Rare Disease (ERD) platform. They capture genotype, phenotype, and progression and include demographic data, biomarkers, comorbidity, medication, magnetic resonance imaging (MRI), and longitudinal clinician- or patient-reported ratings of ataxia severity, non-ataxia features, disease stage, activities of daily living, and (mental) health status. Moreover, they are aligned to major autosomal-dominant spinocerebellar ataxia (SCA) and sporadic ataxia (SPORTAX) registries in the field, thus allowing for joint and comparative analyses not only across ARCAs but also with SCAs and sporadic ataxias. The registry is at the core of a systematic multi-component ARCA database cluster with a linked biobank and an evolving study database for digital outcome measures. Currently, the registry contains more than 800 patients with almost 1,500 visits representing all ages and disease stages; 65% of patients with established genetic diagnoses capture all the main ARCA genes, and 35% with unsolved diagnoses are targets for advanced next-generation sequencing. The ARCA Registry serves as the backbone of many major European and transatlantic consortia, such as PREPARE, PROSPAX, and the Ataxia Global Initiative, with additional data input from SPORTAX. It has thus become the largest global trial-readiness registry in the ARCA field. PB Frontiers media sa SN 1664-2295 YR 2021 FD 2021-06-25 LK https://hdl.handle.net/10668/27385 UL https://hdl.handle.net/10668/27385 LA en DS RISalud RD Apr 8, 2025