A PHASE 2 STUDY OF THE SAFETY, EFFICACY, AND PHARMACODYNAMICS OF RTA 408 IN THE TREATMENT OF FRIEDREICH’S ATAXIA

Inclusion Criteria:

1. Have genetically confirmed Friedreich's ataxia
2. Have a modified FARS score ≥20 and ≤80
3. Be male or female and ≥16 years of age and ≤40 years of age
4. Have no changes to exercise regimen within 30 days prior to Study Day 1 and be willing to remain on the same exercise regimen during the 16-week study period
5. Have the ability to complete maximal exercise testing
6. Be able to swallow capsules

Exclusion Criteria:

1. Have uncontrolled diabetes (HbA1c >11.0%)
2. Have B-type natriuretic peptide value >200 pg/mL
3. Have a history of clinically significant left-sided heart disease and/or clinically significant cardiac disease
4. Have known active fungal, bacterial, and/or viral infection, including human immunodeficiency virus or hepatitis virus (B or C)
5. Have known or suspected active drug or alcohol abuse
6. Have clinically significant abnormalities of clinical hematology or biochemistry, including but not limited to elevations greater than 1.5 times the upper limit of normal of aspartate aminotransferase, or alanine aminotransferase
7. Have any abnormal laboratory test value or serious pre-existing medical condition that, in the opinion of the investigator, would put the patient at risk by study enrollment

8. Have taken any of the following drugs within 7 days prior to Study Day 1 or plan to take any of these drugs during the time of study participation:

   1. Sensitive substrates for cytochrome P450 2C8 or 3A4 (e.g., repaglinide, midazolam, sildenafil)
   2. Moderate or strong inhibitors or inducers of cytochrome P450 3A4 (e.g., carbamazepine, phenytoin, ciprofloxacin, grapefruit juice)
   3. Substrates for p-glycoprotein transporter (e.g., ambrisentan, digoxin)
9. Have participated in any other interventional clinical study within 30 days prior to Study Day 1
10. Have a cognitive impairment that may preclude ability to comply with study procedures
11. Prior participation in a trial with omaveloxolone (RTA 408)