This is a 28-day, multiple-dose, dose-escalation study. It is anticipated that a total of 3 groups of 8 patients each will be enrolled, in which 6 patients in each group will be randomized to receive RTA 402, and 2 patients per group will be randomized to placebo (3:1). Patients will receive treatment daily for 14 days with a starting dose of 5mg, 25mg, or 50mg. Patients will return for follow up visits on Days 16 and 21, and complete end of study procedures on Day 28.