Troriluzole in Adult Participants With Spinocerebellar Ataxia

Inclusion Criteria:

1. Participants with a known or suspected diagnosis of the following specifichereditary ataxias: SCA1, SCA2, SCA3, SCA6, SCA7, SCA8 and SCA10.

2. A participant should have a confirmed genotypic diagnosis from a ClinicalLaboratory Improvement Amendments (CLIA) certified lab (can produce testresults); or,

3. A participant has a family member that has a confirmed genotypic diagnosis froma CLIA certified lab (can produce test results) and must be willing to undergogenetic testing to confirm underlying SCA diagnosis; or,

4. A participant has a confirmed genotypic diagnosis from a lab that is not CLIAcertified and must be willing to undergo genetic testing to confirm underlyingSCA diagnosis; or,

5. A participant has clinical evidence that supports diagnosis of one of theaforementioned SCA genotypes but does not have producible test results from aCLIA certified lab from either a family member or for his or herself and theparticipant must be willing to undergo such testing to confirm the SCAdiagnosis (in this case, site must wait for results of genotypic testing priorto randomization)

6. Ability to ambulate 8 meters without human assistance (canes and other devicesallowed)

7. Screening Modified Functional Scale for the Assessment and Rating of Ataxia (f-SARA)total score ≥3.

8. Score of ≥1 on gait subsection of the f-SARA

9. Determined by the investigator to be medically stable at Baseline/randomization asassessed by medical history, physical examination, laboratory test results, andelectrocardiogram testing.

Exclusion Criteria:

1. A ≥ 2-point difference on the Modified Functional SARA score between screening andbaseline

2. Mini Mental State Exam (MMSE) score <24

3. Any medical condition other than one of the hereditary ataxias specified in theinclusion criteria that could predominantly explain or contribute significantly tothe participants' symptoms of ataxia.

4. A prominent spasticity or dystonia that, in the opinion of the investigator, willcompromise the ability of the SARA instrument to assess underlying ataxia severity.

5. A score of 4 on any individual item (Items 1-4) of the f-SARA

6. Participants should be excluded at screening or baseline if medical conditions havearisen or there is a change in disease status that could confound the ability of theSARA to accurately reflect changes in ataxia severity.

7. Active liver disease or a history of hepatic intolerance to medications that in theinvestigator's judgment, is medically significant.