Clinical trial NCT04261127: Validation of the RADIAL Algorithm for Diagnosis of Autosomal Recessive Cerebellar Ataxia
Official title: Validation of the RADIAL Algorithm for Diagnosis of Autosomal Recessive Cerebellar Ataxia
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Autosomal Recessive Cerebellar Ataxia
Keywords: autosomal recessive cerebellar ataxia
algorithm
genetic diagnosis
Lead sponsor: University Hospital, Strasbourg, France
Sponsor class: OTHER
First posted: 2020-02-07
Enrollment: 400
Sex: ALL
Minimum age (years): 5
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: DIAGNOSTIC

Brief summary: RADIAL is an algorithm which has been developed following a review of the literature on 67 autosomal recessive cerebellar ataxias (ARCA) and personal clinical experience. Frequency and specificity of each feature were defined for each autosomal recessive cerebellar ataxia, and corresponding prediction scores were assigned. Clinical and paraclinical features of patients are entered into the algorithm, and a patient's total score for each ARCA is calculated, producing a ranking of possible diagnoses. Sensitivity and specificity of the algorithm were assessed by blinded analysis of a multinational cohort of 834 patients with molecularly confirmed autosomal recessive cerebellar ataxia. The performance of the algorithm was assessed versus a blinded panel of autosomal recessive cerebellar ataxia experts. The correct diagnosis was ranked within the top 3 highest-scoring diagnoses at a sensitivity and specificity of \>90% for 84% and 91% of the evaluated genes, respectively. Mean sensitivity and specificity of the top 3 highest-scoring diagnoses were 92% and 95%, respectively. Our aim is now to validate in a prospective cohort of ARCA, the performance of RADIAL to predict the correct genetic diagnosis.


Eligibility criteria: Inclusion Criteria:

- For patients:

1. Patient, male or female, over 5 years old (no upper age limit)
2. Patient with cerebellar ataxia who started before the age of 40
3. Patient with a family history compatible with autosomal recessive inheritance (sporadic case, consanguinity, several cases in siblings)
4. Patient in which an acquired cause of cerebellar ataxia has been excluded
5. Patient whose genetic diagnosis is unknown (NB: patients with a known negative result for the Friedreich's disease gene are eligible for inclusion))
6. For patients over 18 years old: patient speaking and reading French, able to give a signed and dated informed consent to participate in the study.

   Patients who have reached the age of majority and whose DNA has been banked and who have signed a consent form authorizing the subsequent use of this DNA for research purposes, including genetic analysis of cerebellar ataxias or associated pathologies, and for whom the RADIAL information sheet can be completed in full, are eligible for inclusion.
7. For patient under 18 years old: Tutor or person with parental authority must speak French and be able to give a signed and dated informed consent for the minor patient.

   Patients who are minors, whose DNA has been banked and for whom the parental authority has signed a consent form authorizing the subsequent use of this DNA for research purposes, including genetic analysis of cerebellar ataxias or associated pathologies, and for whom the RADIAL information sheet can be completed, are eligible.
8. Patient affiliated to the French national health insurance

   - For relatives:
9. Male or female, over 18 years old (no upper age limit)
10. Biological father or mother of a patient included in RADIAL-VALID research protocol
11. (for prospective inclusion only) To be available for a visit to the participating center where the child is being followed
12. Speaking and reading French, able to give a signed and dated informed consent to participate in the study
13. Subject affiliated to the French national health insurance

    Exclusion Criteria:

    - For patients:
14. Patient in whom targeted sequencing of a panel of PMDA genes and/or exome/genome sequencing have already been performed.

    * For patients and related:
15. Subject of a legal protection measure
16. Subject in exclusion period (determined by previous or current study)

Primary outcomes:
measure: Percentage of patients for whom the final genetic diagnosis is in the top 3 of the diagnoses proposed by the RADIAL algorithm (corresponding to the diseases with the 3 highest score given by the algorithm).
timeFrame: At final visit (depending of genetic results from 2 to 24 month maximum after inclusion visit)
Secondary outcomes:
measure: Percentage of patients for whom the final genetic diagnosis is the first diagnosis proposed by the RADIAL algorithm (corresponding to the disease with the highest score given by the algorithm).
timeFrame: At final visit (depending of genetic results from 2 to 24 month maximum after inclusion visit)
measure: Comparison of interpretation times by the clinical-genetic team (genetic and clinical data) with and without the help of the RADIAL algorithm
timeFrame: At final visit (depending of genetic results from 2 to 24 month maximum after inclusion visit)
measure: Comparison of the satisfaction score given by the clinical-genetic team in the interpretation of data with and without the help of the RADIAL algorithm
timeFrame: At final visit (depending of genetic results from 2 to 24 month maximum after inclusion visit)
measure: Influence of RADIAL on genetic diagnosis: percentage of patients whose diagnosis has been reviewed after the clinical-genetic team has learned of the results proposed by RADIAL
timeFrame: At final visit (depending of genetic results from 2 to 24 month maximum after inclusion visit)
measure: Percentage of patients for whom the genome analysis will have detected a new gene.
timeFrame: At final visit (depending of genetic results from 2 to 24 month maximum after inclusion visit)
Other outcomes:
Locations:
city: Besançon
country: France
facility: CHU de Besancon- Neurology
city: Dijon
country: France
facility: CHU de Dijon- Neurology
city: Lille
country: France
facility: CHU Lille- Neurology
city: Marseille
country: France
facility: CHU Marseille- Neurology
city: Montpellier
country: France
facility: CHU Montpellier - Neurology
city: Nancy
country: France
facility: CHU Nancy- Neurology
city: Strasbourg
country: France
facility: CHRU de Strasbourg - Neurology/Pediatrics
city: Toulouse
country: France
facility: CHU Toulouse- Neurology
Study officials:
affiliation: CHRU Strasbourg
name: Tranchant Christine, MD
role: PRINCIPAL_INVESTIGATOR
References: