NCT05177809

RFC1 Natural History Study

• Status: Recruiting
• Phase: —
• Study type: Observational
• Enrollment: 150 (estimated)
• Sponsor: Prof. Dr. Matthis Synofzik · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

This international, multi-center, multi-modal and prospective observational study aims to determine the phenotypic spectrum and the natural progression of the RFC1 repeat expansion disease, and to seek and validate digital, imaging, and molecular biomarkers that aid in diagnosis and serve as outcome measures in future clinical trials of this novel, but frequent ataxia with late adult-onset.

Detailed description

The investigators will perform an international, multi-center, multi-modal, and registry-based standardized prospective Natural History Study (NHS) in RFC1 repeat expansion disease. Participants will be assessed annually. Study visits with a standardized clinical examination will apply several clinical rating scales, and data will be entered into a clinical database (ARCA Registry; www.ARCA-registry.org) customized to the requirements of this specific study. At all study visits, patients will be asked to donate biosamples; biomaterial collection is optional, and participants can elect to participate in sampling of blood, urine, CSF, and/or a skin biopsy. Optionally, and depending on local availability at each participating site, additional examinations may be performed including imaging, quantitative movement and speech analysis, vestibular testing, a neuropsychological examination, or examination of swallowing function, all to fully capture the multisystemic presentation of the RFC1 repeat expansion disease. This study will delineate variable phenotypes of this relatively novel disease, and systematically characterize the longitudinal progression of multi-model biomarkers to determine the most sensitive, comprehensive, and reliable outcomes measures for future therapeutic trials. Here, longitudinal validation of targeted fluid biomarker candidates will be an important part. The multi-modal longitudinal design of the study and its comprehensive assessment will also provide mechanistic insights into the multisystemic evolution of the disease, which will especially allow to track and understand selective as well as overlapping dysfunction of the cerebellum, sensory peripheral nerves, the vestibular system, and additional systems known to be involved in RFC1 disease or 'CANVAS' as its related syndrome.

Conditions

• Ataxia

Interventions

Type	Name	Description
OTHER	Clinical rating scale to measure ataxia disease severity and progression	SARA is a clinical scale developed by Schmitz-Hübsch et al which assesses a range of different impairments in cerebellar ataxia. The scale is made up of 8 items related to gait, stance, sitting, speech, finger-chase test, nose-finger test, fast alternating movements and heel-shin test.

Timeline

• Start date: 2021-12-14
• Primary completion: 2026-12-01
• Completion: 2026-12-01
• First posted: 2022-01-05
• Last updated: 2026-03-31

Locations

10 sites across 7 countries: Australia, Brazil, France, Germany, Italy, New Zealand, Turkey (Türkiye)