Phenotypes, Biomarkers and Pathophysiology in Spastic Ataxias (SPAX-PBP)

  • End date
    Jun 29, 2025
  • participants needed
  • sponsor
    Dr. Rebecca Schule
Updated on 29 May 2022
Accepts healthy volunteers


The aim of this study is to determine the clinical spectrum and natural progression of Spastic Ataxias (SPAX) and related disorders in a prospective multicenter natural history study, identify digital, imaging and molecular biomarkers that can assist in diagnosis and therapy development and study the genetic etiology and molecular mechanisms of these diseases.


The investigators will perform a registry-based standardized prospective Natural History Study (NHS) in SPAX and related disorders. Participants will be seen annually. At study visits a standardized clinical examination will be performed including application of clinical rating scales (selection of rating scales may vary depending on the individual phenotype and specific genotype); data will be entered into a clinical database (HSP Registry; and ARCA Registry; 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, additional examinations may be performed including imaging, quantitative movement analysis, neuropsychological examinations, analysis of patient or observer reported outcomes and OMICS analysis to characterize molecular biomarkers.

In participants without a genetic diagnosis, next generation sequencing may be performed.

Thus this study will establish a model of disease progression and mechanistic evolution in SPAX, which will allow to track and understand selective as well as overlapping dysfunction of the cerebellum and corticospinal tract. In a transatlantic natural history study we will longitudinally validate clinician- and patient-reported, digital and molecular outcomes. In addition, we will improve on existing and develop new outcome parameters that show superior sensitivity to change. These include a novel clinical SPAX composite score, a smartphone mHealth toolbox combining remote assessment of daily living by wearable sensors with app-based patient-entered outcomes (, and multimodal MRI radiomics with an innovative machine learning approach for multisite MRI analysis, including in particular the infratentorial space. Longitudinal validation of targeted fluid biomarker candidates will aslo be an important part.

Condition Spastic Ataxia
Treatment Next-Gen Sequencing (NGS), Clinical rating scale to measure Ataxia disease severity and progression, Clinical rating scale to measure spastic paraplegia disease severity and progression, Disease-specific severity index for adults with autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS)
Clinical Study IdentifierNCT04297891
SponsorDr. Rebecca Schule
Last Modified on29 May 2022


Yes No Not Sure

Inclusion Criteria

ARSACS cohort: genetic diagnosis of ARSACS and clinically manifest disease
SPG7 cohort: genetic diagnosis of SPG7 and clinically manifest disease
Unrelated healthy controls: no signs or history of neurological or psychiatric disease
written informed consent provided
Participants are willing and able to comply with study procedures

Exclusion Criteria

Missing informed consent
For controls: evidence of a neurodegenerative disease or movement disorders; inability to give informed consent
Clear my responses

How to participate?

Step 1 Connect with a study center
What happens next?
  • You can expect the study team to contact you via email or phone in the next few days.
  • Sign up as volunteer  to help accelerate the development of new treatments and to get notified about similar trials.

You are contacting

Investigator Avatar

Primary Contact


Additional screening procedures may be conducted by the study team before you can be confirmed eligible to participate.

Learn more

If you are confirmed eligible after full screening, you will be required to understand and sign the informed consent if you decide to enroll in the study. Once enrolled you may be asked to make scheduled visits over a period of time.

Learn more

Complete your scheduled study participation activities and then you are done. You may receive summary of study results if provided by the sponsor.

Learn more

Similar trials to consider


Browse trials for

Not finding what you're looking for?

Every year hundreds of thousands of volunteers step forward to participate in research. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.

Sign up as volunteer

user name

Added by • 



Reply by • Private

Lorem ipsum dolor sit amet consectetur, adipisicing elit. Ipsa vel nobis alias. Quae eveniet velit voluptate quo doloribus maxime et dicta in sequi, corporis quod. Ea, dolor eius? Dolore, vel!

  The passcode will expire in None.

No annotations made yet

Add a private note
  • abc Select a piece of text from the left.
  • Add notes visible only to you.
  • Send it to people through a passcode protected link.
Add a private note