Ristori 2010.
| Methods | Double‐blind, placebo‐controlled, randomised study | |
| Participants | 40 participants (between 18 and 80 years) with chronic cerebellar ataxia (bilateral involvement of static and kinetic functions, as well as dysarthria and oculomotor dysfunction), irrespective of aetiology Riluzole group: 20 participants (8 male, 12 female), mean age 48.9 (SD 16.8) Control group: 20 participants (7 male, 13 female), mean age 44.1 (SD 13.1) The riluzole group included 10 participants with hereditary ataxia (6 SCA, 3 Friedreich ataxia, 1 fragile X tremor/ataxia syndrome), 5 with sporadic ataxia (3 with probable multiple system atrophy type C (MSA‐C), 1 with anti‐GAD antibodies, 1 with anti‐Yo antibodies) and 5 with ataxic syndromes of unknown origin The placebo group included 7 participants with hereditary ataxia (2 SCA, 5 Friedreich ataxia), 5 with sporadic ataxia (3 with probable MSA‐C, 2 with multiple sclerosis) and 8 with ataxic syndromes of unknown origin |
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| Interventions | Participants received riluzole (50 mg tablets, twice daily) or placebo for a period of 8 weeks. Participants suspended any pharmacological or physical therapy for ataxia for 2 weeks prior to enrolment | |
| Outcomes | Participants were assessed at baseline, 4 weeks and 8 weeks after the beginning of treatment, for symptoms, physical and neurological signs, ICARS score, electrocardiogram and complete standard laboratory safety tests. Treatment efficacy was measured by differences between riluzole and placebo groups in:
The ICARS assessment contains a dysarthria subscale which was only reported separately for the mean change of ICARS scores from baseline to 8 weeks after beginning of treatment |
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| Notes | Only 17 out of 40 participants presented with symptoms caused by hereditary ataxia. Outcomes of the dysarthria subscale only were not reported for either individual participants; or groups according to aetiology or diagnosis Sanofi‐Aventis (Milan, Italy) provided riluzole and matching placebo |
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| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | Participants were randomly assigned in a 1:1 ratio to riluzole or placebo groups. Given the relatively uneven distribution of participants with different diagnoses in the 2 groups, the random nature of the allocation appears clear |
| Allocation concealment (selection bias) | Low risk | A list of randomisation numbers and corresponding treatment numbers was computer‐generated before the start of the study. This procedure was centrally performed by personnel not involved in the study measurements |
| Blinding of participants and personnel (performance bias) All outcomes | Low risk | Both examiner and participant were blinded to treatment |
| Blinding of outcome assessment (detection bias) All outcomes | Low risk | A treating investigator assessed the safety of riluzole and took all the medical decisions on the basis of the clinical and laboratory findings. A second examining investigator had access to the ICARS score but was unaware of the treatment groups until all the data had been collected and analysed (data were first entered into a paper case report form, then into electronic databases for analysis). This prevented the blinding procedure from being broken as a result of observed efficacy, adverse events or changes in laboratory tests |
| Selective reporting (reporting bias) | Low risk | All planned outcomes reported |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | 2 participants (1 in the riluzole and the other in the placebo arm) withdrew their consent before receiving riluzole or placebo and were excluded from the final analysis |
| Other bias | Low risk | None identified |