TreatHSP Platform: Adaptive Natural History Platform for Ataxias, HSPs, and Spastic Ataxias (TreatHSP)

August 28, 2026 updated by: Rebecca Schuele, Heidelberg University

TreatHSP/SPAX Master Protocol: Adaptive Platform for Longitudinal Progression, Biomarkers and Pathophysiology in Ataxias, Hereditary Spastic Paraplegias and Spastic Ataxias (TreatHSP/SPAX)

Ataxias, hereditary spastic paraplegias (HSP), and spastic ataxias (collectively referred to as SPAX diseases) are rare neurological conditions that cause progressive problems with walking, balance, coordination, and daily activities. Although many SPAX diseases are caused by specific genetic changes, there is still limited knowledge about how symptoms develop over time, how fast the diseases progress, and which clinical or biological measures best reflect meaningful changes for patients.

The TreatHSP Master Protocol establishes an adaptive natural history study platform designed to improve the understanding of SPAX diseases across all ages and disease stages. Within this platform, the TreatHSP/SPAX study serves as the core natural history study, providing a shared framework for long-term clinical follow-up, standardized outcome assessments, and biosample collection.

Participants enrolled in TreatHSP/SPAX are followed over time to document disease progression using clinical examinations, patient- and caregiver-reported outcomes, digital movement measures, imaging, and biological samples. In addition to this core dataset, the TreatHSP Platform allows optional, disease- or hypothesis-specific substudies to be added over time in selected participant groups. These additional assessments are introduced under the same master protocol, without creating separate stand-alone studies.

The overall goal of the TreatHSP Master Protocol is to generate high-quality natural history data, identify sensitive and patient-relevant outcome measures, and support the development of future therapies for ataxias, hereditary spastic paraplegias, and spastic ataxias.

Study Overview

Status

Recruiting

Conditions

Detailed Description

Overview and Objectives: The TreatHSP Protocol defines an adaptive observational study platform for natural history research, outcome development, and biomarker discovery in ataxias, hereditary spastic paraplegias (HSP), and spastic ataxias (SPAX diseases). The platform is designed to support longitudinal, regulatory-grade data collection across genetically and clinically heterogeneous rare neurological disorders.

Within the TreatHSP platform, TreatHSP/SPAX represents the core natural history study. All participants are enrolled into TreatHSP/SPAX and undergo a standardized set of core assessments, forming the backbone of the platform. Additional disease- or hypothesis-specific investigations may be conducted within the same platform framework.

The primary objectives of the TreatHSP platform are to:

Characterize the longitudinal clinical course of SPAX diseases across genotypes, ages, and disease stages.

Identify, develop, and validate patient-relevant clinical outcome assessments. Discover and validate molecular, imaging, digital, and functional biomarkers relevant for disease progression, prognosis, and therapy development.

Establish a harmonized data and biosample resource to support clinical trial readiness and secondary research.

Adaptive Platform Design: The TreatHSP Master Protocol follows design principles analogous to interventional platform trials, adapted for observational research. A single master protocol governs all study activities, including governance, ethics, consent, data protection, and quality assurance.

The TreatHSP/SPAX core natural history study defines:

Core eligibility principles Mandatory clinical, functional, and patient-reported assessments Standardized biosample collection Common data elements and anchor outcome measures

Within this framework, additional adaptive Natural History Study appendices may be introduced as protocol amendments. These appendices add optional assessments (e.g. digital mobility monitoring, advanced imaging, biomarker studies) in predefined participant subsets, while preserving the integrity of the core cohort and dataset.

This adaptive design enables parallel investigation of multiple disease subgroups and research questions under a single, continuously evolving protocol.

Study Population:

The platform includes:

Individuals of all ages with a clinical or genetic diagnosis of an ataxia, hereditary spastic paraplegia, or spastic ataxia, including presymptomatic mutation carriers.

Selected affected or unaffected family members. Healthy unrelated control participants for selected analyses.

Registry Procedures and Quality Assurance:

The TreatHSP/SPAX core study functions as a structured patient registry within the TreatHSP Platform and follows predefined quality standards.

Data Collection and Validation:

Data are collected using standardized electronic case report forms. Automated data checks are applied to ensure validity, plausibility, and internal consistency. Queries are generated and resolved by trained study personnel.

Source Data Verification:

Data entered into the registry may be verified against source documents (e.g. medical records, imaging reports, laboratory data) using a risk-based and sample-based approach.

Data Dictionary:

A comprehensive data dictionary defines all variables collected within the platform, including variable definitions, data sources, coding standards (e.g. Human Phenotype Ontology, MedDRA where applicable), and reference ranges when relevant.

Standard Operating Procedures:

Standard Operating Procedures govern patient recruitment, informed consent, data collection, data management, biosample handling, quality control, statistical analysis, reporting, and change management for adaptive protocol amendments.

Monitoring and Auditing:

Central data monitoring and periodic site-level reviews are conducted to ensure data quality, protocol adherence, and compliance with ethical and regulatory requirements.

Sample Size and Statistical Considerations:

Due to the rarity and heterogeneity of SPAX diseases, the TreatHSP Platform does not define a fixed sample size. Enrollment is open-ended to ensure broad representation across disease subtypes. Statistical analyses are primarily longitudinal and descriptive, with detailed analysis plans defined for specific substudies as needed.

Handling of Missing Data:

Missing data are explicitly documented and categorized. Statistical analyses account for missing data using appropriate longitudinal methods and sensitivity analyses, depending on the research question.

Data Protection and Governance:

All data are pseudonymized and handled in accordance with applicable data protection regulations. Access to identifiable information is restricted to authorized personnel. Data sharing for secondary research is governed by defined access procedures and ethical approvals.

Study Type

Observational

Enrollment (Estimated)

4000

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Name: Perdita Beck, Study coordinator
Phone Number: +49 6221 56-38121
Email: Perdita.Beck@med.uni-heidelberg.de

Study Locations

Austria
- - Innsbruck, Austria, 6020
    - Recruiting
    - Medical University Innsbruck, Department of Neurology
    - Contact:
      
      Sylivia Boesch, MSc, Priv. Doz. Dr.
      
      Phone Number: +43 512 504-83686
      
      Email: Sylvia.Boesch@i-med.ac.at
    - Principal Investigator:
      
      Sylivia Boesch, MSc, Priv. Doz. Dr.
    - Sub-Investigator:
      
      Matthias Amprosi, PhD, Dr.
Czechia
- - Prague, Czechia, 150 00
    - Recruiting
    - Centre of Hereditary Ataxias, Department of Neurology and Department of Pediatric Neurology, 2nd Faculty of Medicine, Charles University and Motol and Homolka University Hospital
    - Contact:
      
      Jaroslava Paulasová Schwabova, M.D., Ph.D.
      
      Phone Number: +420 224 431 111
      
      Email: jaroslava.schwabova@fnmotol.cz
    - Principal Investigator:
      
      Jaroslava Paulasová Schwabova, M.D., Ph.D.
    - Sub-Investigator:
      
      Ludmilla Novotá, M.D.
    - Sub-Investigator:
      
      Anna Uhrová Mészárosová, M.D.
    - Sub-Investigator:
      
      Dana Šafka Brožková, M.D.
    - Sub-Investigator:
      
      Emílie Vyhnálková, M.D.
    - Sub-Investigator:
      
      Lukáš Martinkovič, M.D.
    - Sub-Investigator:
      
      Martin Vyhnálek, M.D.
France
- - Paris, France, 75646
    - Recruiting
    - Paris Brain Institute ICM CRMR Neurogénétique, Hôpital de la Pitié-Salpêtrière Sorbonne Université UM75 Inserm U1127 CNRS UMR 7225 47 boulevard de l'Hôpital, CS21414
    - Contact:
      
      Hortense Hurmic, Clinical research assistant
      
      Phone Number: +33 (0)157274606
      
      Email: hortense.hurmic@icm-institute.org
    - Principal Investigator:
      
      Alexandra Dürr, Prof. Dr.
    - Sub-Investigator:
      
      Giulia Coarelli, Dr.
Germany
- - Bochum, Germany, 44801
    - Recruiting
    - Ruhr University Bochum, Institute for Neuroinformatics (INI)
    - Contact:
      
      Xenia Kobeleva, Prof. Dr.
      
      Phone Number: +49 (0) 234 32-28967
      
      Email: research@xenia-kobeleva.com
    - Principal Investigator:
      
      Xenia Kobeleva, Prof. Dr.
  - Bonn, Germany, 53127
    - Recruiting
    - German Center for Neurodegenerative Diseases (DZNE) Bonn University Hospital Bonn Clinic for Parkinson's, sleep and movement disorders
    - Contact:
      
      Jennifer Faber, PD Dr.
      
      Phone Number: +49 (0)228 287-15736
      
      Email: Jennifer.Faber@dnze.de
    - Principal Investigator:
      
      Jennifer Faber, PD Dr.
    - Sub-Investigator:
      
      Sarah Bernsen, Dr.
    - Sub-Investigator:
      
      Okka Kimmich, Dr.
    - Sub-Investigator:
      
      Dennis deConnick, Dr.
  - Dresden, Germany, 01307
    - Recruiting
    - German Center for Neurodegenerative Diseases (DZNE) Dresden; University Hospital Carl Gustav Carus Clinic and Polyclinic for Neurology
    - Contact:
      
      Falkenburger Björn, Prof. Dr.
      
      Phone Number: +49 351 458-2532
      
      Email: bjoern.falkenburger@dzne.de
    - Principal Investigator:
      
      Björn Falkenburger, Prof. Dr.
    - Sub-Investigator:
      
      Hanna-Sophie Lapp, Dr.
  - Erlangen, Germany, 91054
    - Recruiting
    - University Hospital Erlangen, Department of Neurology
    - Contact:
      
      Regensburger Martin, Prof. Dr.
      
      Phone Number: +49 (0) 9131 85-39324
      
      Email: martin.regensburger@uk-erlangen.de
    - Principal Investigator:
      
      Martin Regensburger, Prof. Dr.
    - Principal Investigator:
      
      Jürgen Winkler, Prof. Dr.
    - Sub-Investigator:
      
      Heiko Gaßner, Dr.
    - Sub-Investigator:
      
      Beate Winner, Prof. Dr.
    - Sub-Investigator:
      
      Jelena Jukic, Dr.
    - Sub-Investigator:
      
      Patrick Süß, Dr.
    - Sub-Investigator:
      
      Christina Matlok, Dr.
  - Essen, Germany, 45147
    - Recruiting
    - University Hospital Essen, Department of Pediatric Neurology / Institute of Human Genetics
    - Contact:
      
      Bilge Albayrak, Dr.
      
      Phone Number: 49 (0) 201-723 2178
      
      Email: Bilge.Albayrak@uk-essen.de
    - Principal Investigator:
      
      Bilge Albayrak, Dr.
    - Principal Investigator:
      
      Frederik Braun, Dr.
    - Sub-Investigator:
      
      Ulrike Schara-Schmidt, Prof. Dr.
  - Göttingen, Germany, 37075
    - Recruiting
    - German Center for Neurodegenerative Diseases (DZNE) Göttingen
    - Contact:
      
      Lisa Reinecke, Study Coordination
      
      Phone Number: +49 (0) 551-39 61166
      
      Email: sz-umg.neurologie@med.uni-goettingen.de
    - Principal Investigator:
      
      Christoph van Riesen, Dr. med
  - Göttingen, Germany, 37075
    - Recruiting
    - University Hospital Göttingen, Department of Neurology
    - Contact:
      
      Sandrin Plewe, Study Coordination
      
      Phone Number: +49 (0) 551-39 64162
      
      Email: sandrin.plewe@med.uni-goettingen.de
    - Principal Investigator:
      
      Michael Sereda, Prof. Dr.
    - Sub-Investigator:
      
      Ahmad Beschad, Dr.
  - Göttingen, Germany, 37075
    - Recruiting
    - University Medical Centre Göttingen, Clinic for Paediatric and Adolescent Medicine
    - Contact:
      
      Lara Marten, Dr.
      
      Phone Number: +49 (0) 551-39 67019
      
      Email: lara.marten@med.uni-goettingen.de
    - Principal Investigator:
      
      Lara Marten, Dr.
  - Heidelberg, Germany, 69120
    - Recruiting
    - University Hospital Heidelberg, Department of Neurology
    - Contact:
      
      Perdita Beck, Study Coordinator
      
      Phone Number: +4962215638121
      
      Email: Perdita.Beck@med.uni-heidelberg.de
    - Principal Investigator:
      
      Rebecca Schuele, Prof. Dr. med.
    - Sub-Investigator:
      
      Hanna Boelting, Dr. med.
    - Sub-Investigator:
      
      Mirlinda Ademi, Dr. med. univ., PhD
    - Sub-Investigator:
      
      Vanessa Crncovic, Dr. med.
  - Heidelberg, Germany, 69124
    - Recruiting
    - Heidelberg University Hospital, Center for Child and Adolescent Medicine
    - Contact:
      
      Stefan Kölker, Prof. Dr.
      
      Phone Number: +49 (0) 6221-56 4002
      
      Email: stefan.koelker@med.uni-heidelberg.de
    - Principal Investigator:
      
      Afshin Saffari, Dr.
    - Sub-Investigator:
      
      Birgit Assmann, PD Dr.
  - Kiel, Germany, 24105
    - Recruiting
    - University Hospital Schleswig-Holstein , Department of Neurology
    - Contact:
      
      Beate Lengl-Janssen, Dr. rer. nat.
      
      Phone Number: +49 (0) 431 500-24011
      
      Email: lotsinzsne.kiel@uksh.de
    - Principal Investigator:
      
      Tim W. Rattay, PD. Dr. med.
  - Magdeburg, Germany, 39120
    - Recruiting
    - German Center for Neurodegenerative Diseases (DZNE) Magdeburg, University Hospital Magdeburg, Department of Neurology
    - Contact:
      
      Deike Hartmann, Study Coordination
      
      Phone Number: +49 (0) 391/67-24535
      
      Email: deike.hartmann@dzne.de
    - Principal Investigator:
      
      Michaela Butryn, Dr.
    - Sub-Investigator:
      
      Wenzel Glanz, Dr.
  - München, Germany, 80336
    - Recruiting
    - German Center for Neurodegenerative Diseases (DZNE) Munich, Munich University Hospital LMU, Department of Neurology
    - Principal Investigator:
      
      Thomas Klopstock, Prof. Dr.
    - Contact:
      
      Büchner Boriana, Dr. (Study coordination)
      
      Phone Number: +49 (0)89 4400 57421
      
      Email: boriana.buechner@med.uni-muenchen.de
    - Sub-Investigator:
      
      Leopold Zeng, Dr.
    - Sub-Investigator:
      
      Almut Bischoff, Dr.
  - Recklinghausen, Germany, 45657
    - Recruiting
    - Klinikum Vest GmbH, Treatment Center Knappschafts Hospital Recklinghausen, NeuroCentrum - Department of Neurology, Stroke Unit and Early Rehabilitation
    - Principal Investigator:
      
      Stephan Klebe, Prof. Dr.
    - Contact:
      
      Nicole Jeschonneck, Study Coordination
      
      Phone Number: +49 (0) 2361 56-83745
      
      Email: Nicole.Jeschonneck@Knappschaft-Kliniken.de
  - Tübingen, Germany, 72076
    - Recruiting
    - University Hospital and Faculty of Medicine Tübingen, Clinic for Paediatrics and Adolescent Medicine
    - Contact:
      
      Hendrik Rosewich
      
      Phone Number: +49 (0) 0201-723-2508
      
      Email: Hendrik.Rosewich@med.uni-tuebingen.de
    - Principal Investigator:
      
      Hendrik Rosenwich, Prof. Dr.
    - Sub-Investigator:
      
      Marion Doebler-Neumann, Dr.
  - Tübingen, Germany, 72076
    - Recruiting
    - University Hospital and Faculty of Medicine Tübingen, Neurology with a Focus on Neurodegenerative Diseases
    - Principal Investigator:
      
      Ludger Schöls, Prof. Dr.
    - Contact:
      
      Katrin Dillmann-Jehn, Study Coordination
      
      Phone Number: +49 (0) 7071 29-85653
      
      Email: Katrin.Dillmann@med.uni-tuebingen.de
    - Sub-Investigator:
      
      Lena Zelter, Dr.
    - Sub-Investigator:
      
      Zofia Fleszar, Dr.
    - Sub-Investigator:
      
      Johanna Roller, Dr.
Ireland
- - Dublin, Ireland, Dublin 24
    - Recruiting
    - Tallaght University Hospital, Neurology
    - Contact:
      
      Sinead Murphy, MD, Prof.
      
      Phone Number: +353 1 414 4061
      
      Email: Sinead.Murphy@tuh.ie
    - Principal Investigator:
      
      Sinead Murphy, MD, Prof.
    - Principal Investigator:
      
      Petya Bogdanova-Mihaylova, Dr.
    - Principal Investigator:
      
      Richard Walsh, Dr.
    - Sub-Investigator:
      
      Eva Tallon, Dr.
Italy
- - Pisa, Italy, 56126
    - Recruiting
    - University of Pisa, Azienda Ospedaliero Universitaria Pisana, Neurology
    - Contact:
      
      Michelangelo Mancuso, Prof. Dr.
      
      Phone Number: +39 (0) 50 992443
      
      Email: michelangelo.mancuso@unipi.it
    - Principal Investigator:
      
      Michelangelo Mancuso, Prof. Dr.
    - Sub-Investigator:
      
      Adriana Meli, Dr.
    - Sub-Investigator:
      
      Clara Bernardini, Dr.
    - Sub-Investigator:
      
      Vicenzo Montano, Dr.
    - Sub-Investigator:
      
      Piervito Lopriore, Dr.
  - Roma, Italy, 00146
    - Recruiting
    - IRCCS Istituto Ospedale Pediatrico Bambino Gesù, Translational Pediatrics and Clinical Genetics
    - Contact:
      
      Enrico S Bertini, Prof. Dr.
      
      Phone Number: +39 (0) 668592104
      
      Email: enricosilvio.bertini@opbg.net
    - Principal Investigator:
      
      Enrico S Bertini, Prof. Dr.
    - Sub-Investigator:
      
      Francesco Nicita, Dr.
    - Sub-Investigator:
      
      Jacopo Sartorelli, Dr.
    - Sub-Investigator:
      
      Gessica Vasco, Dr.
    - Sub-Investigator:
      
      Andrea Sancesario, Dr.
  - Roma, Italy, 00168
    - Recruiting
    - Università Cattolica del Sacro Cuore, Department of Neuroscience
    - Contact:
      
      Gabriella Silvestri, Prof. Dr.
      
      Phone Number: +39 (06) 30154338
      
      Email: Gabriella.Silvestri@unicatt.it
    - Principal Investigator:
      
      Gabriella Silvestri, Prof. Dr.
    - Sub-Investigator:
      
      Salvatore Rossi, Dr.
- Pisa
  - Calambrone, Pisa, Italy, 56018
    - Recruiting
    - IRCCS Fondazione Stella Maris, MEDMOL - Molecular Medicine, Neurogenetics and Neuromuscular Diseases
    - Sub-Investigator:
      
      Sara Satolli, MD
    - Contact:
      
      Filippo Santorelli, Prof. Dr.
      
      Phone Number: +39 (0) 50 886238
      
      Email: filippo3364@gmail.com
    - Principal Investigator:
      
      Filippo Santorelli, Prof. Dr.
    - Sub-Investigator:
      
      Ilaria D Donato, MD
    - Sub-Investigator:
      
      Gianmarco Dalla Zanna, MD
    - Sub-Investigator:
      
      Nunzio Setola, MD
- TV
  - Conegliano, TV, Italy, 31015
    - Recruiting
    - Associazione La Nostra Famiglia - IRCCS Eugenio Medea
    - Contact:
      
      Andrea Martinuzzi, Prof. Dr.
      
      Phone Number: +39 (0)438 - 414242
      
      Email: andrea.martinuzzi@lanostrafamiglia.it
    - Principal Investigator:
      
      Andrea Martinuzzi, Prof. Dr.
    - Sub-Investigator:
      
      Elena Carrero, Dr.
    - Sub-Investigator:
      
      Leonardo Boccuni, Dr.
    - Sub-Investigator:
      
      Francesca Oppia, Dr.
    - Sub-Investigator:
      
      Gabriella Paparella, Dr.
Netherlands
- - Nijmegen, Netherlands, 6525 GA
    - Recruiting
    - Radboud university medical center - Radboundumc, University Medical Center
    - Contact:
      
      Bart van de Warrenburg, Prof. Dr.
      
      Phone Number: +31 (0) 24 361 11 11
      
      Email: Bart.vandeWarrenburg@radboudumc.nl
    - Principal Investigator:
      
      Bart van de Warrenburg, Prof. Dr.
    - Sub-Investigator:
      
      Jorik Nonnekes, Dr.
    - Sub-Investigator:
      
      Lotte van de Venis, Dr.
Poland
- - Krakow, Poland, 30-688
    - Recruiting
    - University Hospital in Kraków, Neurology Clinical Department
    - Contact:
      
      Joanna Pera, Prof. Dr.
      
      Phone Number: +48 (0) 12 424 86 15
      
      Email: pera@su.krakow.pl
    - Principal Investigator:
      
      Joanna Pera, Prof. Dr.
Spain
- - Barcelona, Spain, 08950
    - Recruiting
    - Hospital Sant Joan de Déu Barcelona, Neuromuscular Diseases Unit
    - Contact:
      
      Laura Carrera Garcia, Dr.
      
      Phone Number: +34 (0) 93 253 21 00
      
      Email: laura.carrera@sjd.es
    - Principal Investigator:
      
      Laura Carrera Garcia, Dr.
    - Sub-Investigator:
      
      Carlos I Ortez González, Dr.
    - Sub-Investigator:
      
      Alejandra Darling, Dr.
    - Sub-Investigator:
      
      Julita Medina, Dr.
  - Barcelona, Spain
    - Recruiting
    - Vall d'Hebron Barcelona Hospital Campus, Vall d'Hebron University Hospital - Neurology Department
    - Contact:
      
      Alfons Macaya, Prof. Dr.
      
      Phone Number: +34 (0) 93 489 31 56
      
      Email: alfons.macaya@vallhebron.cat
    - Principal Investigator:
      
      Alfons Macaya, Prof. Dr.
    - Principal Investigator:
      
      Maria Victoria González Martinez, Dr.
    - Sub-Investigator:
      
      Paula Arranz-Horno, Dr.
    - Sub-Investigator:
      
      Natalia Espandin-Hüter, Dr.
  - Santander, Spain, 39008
    - Recruiting
    - University Hospital Marqués de Valdecilla-IDIVAL, Department of Neurology
    - Contact:
      
      Jon Infante, MD, PhD
      
      Phone Number: +34 (0) 616416622
      
      Email: jon.infante@scsalud.es
    - Principal Investigator:
      
      Jon Infante, MD, PhD
    - Sub-Investigator:
      
      Leire Manrique, Dr.
    - Sub-Investigator:
      
      Raquel Martinez, Dr.

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

Child
Adult
Older Adult

Accepts Healthy Volunteers

Yes

Sampling Method

Non-Probability Sample

Study Population

Children, adolescents, and adults aged 5 years and older are recruited through multicenter, international participation from specialized neurology and genetics clinics, patient registries, affected families, and the general community. The study includes individuals with ataxia, spastic ataxia, hereditary spastic paraplegia, or related phenotypes; presymptomatic mutation carriers; first- or second-degree relatives of affected individuals; and neurologically healthy community controls.

Description

Inclusion Criteria:

General inclusion criteria:

- Age 5 or older

Cohort 1: Affected

Clinical diagnosis of neurodevelopmental or neurodegenerative ataxia, spastic ataxia, HSP or related phenotype AND
Alternative causes of phenotype excluded

Cohort 2: Presymptomatic mutation carriers

- Premanifest mutation carrier of (likely) pathogenic variant(s) in a disease gene associated with ataxia, spastic ataxia, HSP or related phenotype

Cohort 3: Family controls - 1st or 2nd degree relative of a person with a clinical or genetic diagnosis of ataxia, spastic ataxia, HSP or related phenotype

Cohort 4: Community controls

- Healthy individual unrelated to a person with neurodevelopmental or neurodegenerative ataxia, spastic ataxia, HSP or related phenotype

Exclusion Criteria:

Presence of an alternative neurological or systemic condition that sufficiently explains the phenotype and is incompatible with ataxia, spastic ataxia, hereditary spastic paraplegia, or a related disorder.
Severe comorbidity or unstable medical condition that substantially interferes with study participation or interpretation of neurological and functional assessments.
Inability to comply with study procedures or follow-up requirements.
Lack of informed consent, including absence of consent by a legally authorized representative where required.
Current participation in an interventional clinical trial that may interfere with the objectives or outcome assessments of this observational study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort Group / Cohort A group or subgroup of participants in an observational study that is assessed for biomedical or health outcomes.
Affected Clinical diagnosis of neurodevelopmental or neurodegenerative ataxia, spastic ataxia, HSP and alternative cause of phenotype excluded
Presymptomatic mutation carrier Premanifest mutation carrier of (likely) pathogenic variant(s) in a disease gene associated with ataxia, spastic ataxia, HSP or related phenotype
Family control 1st or 2nd degree relative of a person with a clinical or genetic diagnosis of ataxia, spastic ataxia, HSP or related phenotype (group: Affected)
Community control Healthy individual unrelated to a person with neurodevelopmental or neurodegenerative ataxia, spastic ataxia, HSP or related phenotype

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Modified Spastic Paraplegia Rating Scale Time Frame: Through study completion, an average of 5 years, measured annually	The modified Spastic Paraplegia Rating Scale (mSPRS) is a clinician-reported outcome measure assessing disease severity in hereditary spastic paraplegia and related spastic movement disorders. It evaluates functional mobility, spasticity, muscle strength, pain and bladder function. The mSPRS is adapted from the original Spastic Paraplegia Rating Scale to improve feasibility and sensitivity to change in longitudinal studies. It can be applied in individuals aged 5 years and older, with higher scores indicating greater disease severity. The mSPRS serves as the primary outcome measure for the assessment of disease severity in all participants with hereditary spastic paraplegia.	Through study completion, an average of 5 years, measured annually
Scale for the Assessment and Rating of Ataxia (SARA) Time Frame: Through study completion, an average of 5 years, measured annually	The Scale for the Assessment and Rating of Ataxia (SARA) is a standardized clinician-reported outcome measure used to quantify the severity of ataxia. It assesses key domains including gait, stance, sitting, speech disturbance, limb coordination, and fine motor control. The SARA provides a global measure of ataxia-related motor impairment and is widely used in both clinical practice and longitudinal research studies. The SARA is applied in study participants aged 8 years and older, with higher scores indicating greater ataxia severity. The SARA serves as the primary outcome measure for the assessment of disease severity in all participants with ataxia.	Through study completion, an average of 5 years, measured annually
SPAX Composite Scale (SPAXCOM) Time Frame: Through study completion, an average of 5 years, measured annually	SPAXCOM is a clinician-reported composite outcome measure developed to assess disease severity in individuals with spastic ataxia. It integrates key motor and functional domains relevant to spastic-ataxic phenotypes, including gait and balance, coordination, spasticity, and functional mobility. SPAXCOM is designed to capture the combined contribution of pyramidal and cerebellar dysfunction and to provide a sensitive measure of disease severity and progression in spastic ataxia. Higher scores indicate greater disease severity. SPAXCOM serves as the primary outcome measure for participants with spastic ataxia.	Through study completion, an average of 5 years, measured annually

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Friedreich Ataxia Rating Scale - Activities of Daily Living (FARS-ADL) Time Frame: Through study completion, an average of 5 years, measured annually	The Friedreich Ataxia Rating Scale - Activities of Daily Living (FARS-ADL) assesses the impact of neurological impairment on everyday functioning, including walking, balance, speech, hand function, and self-care. In this study, both a clinician-reported (ClinRO) version and a patient-reported (PROM) version of the FARS-ADL are used to capture functional limitations from complementary perspectives and are applied in study participants aged 8 years and older. Although originally developed for Friedreich ataxia, the FARS-ADL is applicable across a range of ataxic and spastic movement disorders. Higher scores indicate greater functional impairment and reduced independence in daily activities.	Through study completion, an average of 5 years, measured annually
Inventory of Non-Ataxia Signs - PLUS (INAS-PLUS) Time Frame: Through study completion, an average of 5 years, measured annually	INAS-PLUS is a clinician-reported inventory, derived from the original Inventory of Non-Ataxia Signs (INAS) and expanded by additional items, used to quantify the burden of neurological signs beyond core ataxia features in spastic and spastic-ataxic disorders.	Through study completion, an average of 5 years, measured annually
MRC Sum Score for Muscle Strength Time Frame: Through study completion, an average of 5 years, measured annually	The Medical Research Council (MRC) Sum Score is a clinician-reported measure of global muscle strength based on standardized manual muscle testing across selected muscle groups. Individual muscle grades are summed to provide an overall estimate of muscle strength, with lower scores indicating greater weakness.	Through study completion, an average of 5 years, measured annually
TreatHSP Quality of Life (TreatHSP-QoL) Time Frame: Through study completion, an average of 5 years, measured annually	The TreatHSP Quality of Life (TreatHSP-QoL) questionnaire is a disease-specific patient-reported outcome measure assessing health-related quality of life, including physical, functional, and psychosocial aspects, and is used in adults aged 18 years and older with hereditary spastic paraplegia and spastic ataxia.	Through study completion, an average of 5 years, measured annually
Caregiver Priorities and Child Health Index of Life with Disabilities (CPCHILD) Time Frame: Through study completion, an average of 5 years, measured annually	The Caregiver Priorities and Child Health Index of Life with Disabilities (CPCHILD) is a caregiver-reported outcome measure developed for children and adolescents with motor disabilities. In this study, the CPCHILD is applied in all children aged 5 to 12 years, as well as in older individuals with cognitive impairment who are unable to reliably complete self-reported questionnaires.	Through study completion, an average of 5 years, measured annually

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
FARS Functional Staging Time Frame: Through study completion, an average of 5 years, measured annually	The Friedreich Ataxia Rating Scale - Functional Staging (FARS-FS) is an ordinal measure of functional disease severity based on mobility and independence in activities of daily living. In this study, both a clinician-reported (ClinRO) version and a patient-reported (PROM) version of the FARS-FS are used to capture functional status from complementary perspectives. The FARS-FS serves as an anchor measure to support the determination and interpretation of clinically meaningful change in primary and secondary outcome measures over time.	Through study completion, an average of 5 years, measured annually
SPATAX Disability Stage Time Frame: Through study completion, an average of 5 years, measured annually	SPATAX Disability Stage is a clinician-reported ordinal staging system that categorizes overall disability based on mobility and functional dependence. It provides a global measure of disease severity and is used in this study as an anchor measure to support the interpretation of clinically meaningful change in primary and secondary outcomes.	Through study completion, an average of 5 years, measured annually
Clinical Global and Domain-Specific Impression of Severity and Change (CGI-S/CGI-C) Time Frame: Through study completion, an average of 5 years, measured annually	Clinical Global and Domain-Specific Impression of Severity and Change are clinician-reported assessments capturing overall disease severity and longitudinal change, as well as change within specific functional domains. The selected domains reflect disease impacts prioritized by individuals with SPAX diseases for their relevance to everyday life. These measures are used as anchor measures to contextualize and determine meaningful change in primary and secondary outcome measures.	Through study completion, an average of 5 years, measured annually
Patient-reported Global and Domain-Specific Impression of Severity and Change (PGI-S / PGI-C) Time Frame: Through study completion, an average of 5 years, measured annually	Patient-reported Global and Domain-Specific Impression of Severity and Change are self-reported assessments capturing overall disease severity and longitudinal change, as well as change within specific functional domains. The selected domains reflect disease impacts prioritized by individuals with SPAX diseases for their relevance to everyday life. These patient-reported measures are used as anchor measures to support the interpretation and determination of clinically meaningful change in primary and secondary outcome measures.	Through study completion, an average of 5 years, measured annually
Functional Mobility Scale (FMS) Time Frame: Through study completion, an average of 5 years, measured annually	The Functional Mobility Scale (FMS) is a clinician-reported measure of functional walking ability that classifies mobility across different distances and everyday environments. It provides an ordinal assessment of functional mobility and is used in this study as an anchor measure to support the interpretation of clinically meaningful change in primary and secondary outcome measures.	Through study completion, an average of 5 years, measured annually
The Gross Motor Function Classification - MLD (GMFC-MLD) Time Frame: Through study completion, an average of 5 years, measured annually	The Gross Motor Function Classification - MLD (GMFC-MLD) is a clinician-reported ordinal classification system used to describe gross motor function and mobility limitations in children. It categorizes functional abilities based on age-appropriate motor skills and need for assistance. In this study, the GMFC-MLD is used as an anchor measure to support the interpretation of clinically meaningful change in outcome measures in children aged 5 to 12 years.	Through study completion, an average of 5 years, measured annually
TreatHSP Mobility Questionnaire Time Frame: Through study completion, an average of 5 years, measured annually	The Mobility Change Questionnaire is a patient- or observer-reported anchor measure assessing perceived change in walking ability over the preceding week compared with the previous study visit. It captures mobility-related domains including walking distance and speed, effort, balance confidence, fear of falling, and overall walking ability. Depending on age and cognitive status, the questionnaire is completed by the participant or an observer and is used to support the interpretation of clinically meaningful change in primary and secondary outcome measures.	Through study completion, an average of 5 years, measured annually
Achievement of developmental milestones Time Frame: Through study completion, an average of 5 years, measured annually	Achievement of key developmental motor milestones (unsupported sitting, unsupported standing, assisted walking, unsupported walking) will be assessed via caregiver/patient report. For each milestone, achievement status will be recorded as yes/no/unknown. Age at achievement will be reported in months for milestones confirmed as achieved. Where an exact age cannot be recalled, this will be noted as either delayed-but-unrecalled or achieved-at-normal-age-but-unrecalled.	Through study completion, an average of 5 years, measured annually
Milestone regression Time Frame: Through study completion, an average of 5 years, measured annually	Loss of previously achieved motor function will be assessed via caregiver/patient report across four regression milestones: new requirement for sitting support, new requirement for standing support, new requirement for a walking aid (used for >50% of walking activity), and new requirement for a wheelchair (used for >50% of locomotion). For each milestone, status will be recorded as yes/no/unknown, with the calendar year of onset documented where applicable.	Through study completion, an average of 5 years, measured annually

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Heidelberg University

Collaborators

National Institute of Neurological Disorders and Stroke (NINDS)

University Hospital Heidelberg

Horizon Europe

Bundesministerium für Forschung, Technologie und Raumfahrt (BMFTR)

European Reference Network for Rare Neurological Diseases (ERN-RND)

Investigators

Principal Investigator: Rebecca Schuele, Prof. Dr. med., Heidelberg University Hospital and Heidelberg Faculty of Medicine

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

The TreatHSP website provides publicly accessible information on the TreatHSP Platform and the TreatHSP/SPAX study, including study objectives, participation information, and updates on ongoing research activities.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

July 16, 2024

Primary Completion (Estimated)

December 31, 2035

Study Completion (Estimated)

December 31, 2035

Study Registration Dates

First Submitted

December 30, 2025

First Submitted That Met QC Criteria

August 28, 2026

First Posted (Actual)

September 1, 2026

Study Record Updates

Last Update Posted (Actual)

September 1, 2026

Last Update Submitted That Met QC Criteria

August 28, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

S-317/2024 TreatHSP
2R01NS072248 (U.S. NIH Grant/Contract)
TreatHSP Registry (Registry Identifier: TreatHSP Registry)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

De-identified individual participant data collected within the TreatHSP Master Protocol may be shared for secondary research purposes. Data eligible for sharing include selected clinical, functional, patient-reported, digital, imaging, and biomarker data generated within the TreatHSP/SPAX core study and approved adaptive substudies. Data sharing is subject to approval through the TreatHSP governance framework and requires submission of a scientific proposal, review by the Steering Committee, and execution of a data use agreement. Only pseudonymized data will be shared, and access will be limited to the minimum dataset necessary to address the approved research question. Data sharing will occur in compliance with applicable data protection regulations and participant consent.

IPD Sharing Time Frame

Beginning January 2026 with no end date.

IPD Sharing Access Criteria

Access requests must be submitted as a research proposal describing the planned analyses and required data elements. Requests are reviewed by the TreatHSP Steering Committee or a delegated data access body based on scientific merit, feasibility, and compliance with ethical and data protection requirements. Approved requests require a data use agreement, and access is limited to the minimum dataset necessary for the approved analyses.

IPD Sharing Supporting Information Type

STUDY_PROTOCOL

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Studies a U.S. FDA-regulated device product

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

TreatHSP Platform: Adaptive Natural History Platform for Ataxias, HSPs, and Spastic Ataxias (TreatHSP)

TreatHSP/SPAX Master Protocol: Adaptive Platform for Longitudinal Progression, Biomarkers and Pathophysiology in Ataxias, Hereditary Spastic Paraplegias and Spastic Ataxias (TreatHSP/SPAX)

Study Overview

Status

Conditions

Detailed Description

Study Type

Enrollment (Estimated)

Contacts and Locations

Study Contact

Study Locations

Participation Criteria

Eligibility Criteria

Ages Eligible for Study

Accepts Healthy Volunteers

Sampling Method

Study Population

Description

Study Plan

How is the study designed?

Design Details

Number of groups / cohorts

Cohorts and Interventions

Group / Cohort

What is the study measuring?

Primary Outcome Measures

Outcome Measure

Measure Description

Time Frame

Secondary Outcome Measures

Outcome Measure

Measure Description

Time Frame

Other Outcome Measures

Outcome Measure

Measure Description

Time Frame

Collaborators and Investigators

Sponsor

Collaborators

Investigators

Publications and helpful links

Helpful Links

Study record dates

Study Major Dates

Study Start (Actual)

Primary Completion (Estimated)

Study Completion (Estimated)

Study Registration Dates

First Submitted

First Submitted That Met QC Criteria

First Posted (Actual)

Study Record Updates

Last Update Posted (Actual)

Last Update Submitted That Met QC Criteria

Last Verified

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

IPD Plan Description

IPD Sharing Time Frame

IPD Sharing Access Criteria

IPD Sharing Supporting Information Type

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Studies a U.S. FDA-regulated device product