A Study of the Safety, Tolerability, and Pharmacokinetics of Single and Multiple Doses of RTA 901 in Healthy Adults

Inclusion Criteria: * Male or female and age is between 18 and 55 years, inclusive. * Women must be of non-childbearing potential and may not be pregnant, lactating, or breast-feeding. Non-childbearing potential is defined by at least one of the following criteria: 1. At least 2 years spontaneous amenorrhea (not attributable to environmental or pathological causes, e.g., anorexia or excessive exercise) with follicle-stimulating hormone (FSH) in post-menopausal range at screening; 2. At least 3 months post-surgical bilateral oophorectomy or tubal ligation; or 3. Hysterectomy (must be greater than 5 years post-hysterectomy if due to cancer); * Females must have negative results for pregnancy tests performed: 1. At screening based on a urine specimen obtained within 28 days prior to initial study drug administration, and 2. Prior to dosing based on a serum sample obtained on Day -1. * If male, subject must be surgically sterile or practicing at least 1 of the following methods of contraception, from initial study drug administration through 90 days after administration of the last dose of study drug: 1. Partner(s) using an IUD; 2. Partner(s) using hormonal contraceptives (oral, vaginal, parenteral, or transdermal). 3. Subject and/or partner(s) using double-barrier method (condoms, contraceptive sponge, diaphragm, or vaginal ring with spermicidal jellies or creams); 4. Total abstinence from sexual intercourse as the preferred life style of the subject; periodic abstinence is not acceptable. * If male, subject agrees to abstain from sperm donation through 90 days after administration of the last dose of study drug. * Body Mass Index (BMI) is ≥ 18 to \< 32 kg/m2, inclusive. * A condition of general good health, based upon the results of a medical history, physical examination, vital signs, laboratory profile, and a 12-lead electrocardiogram (ECG), as judged by the investigator. * Must voluntarily sign and date each informed consent, approved by an Institutional Review Board (IRB), prior to the initiation of any screening or study-specific procedures. Exclusion Criteria: * History of clinically significant drug allergies, including allergies to any of the components of the investigational product and/or clinically significant food allergies as determined by the investigator; History of clinically significant drug allergies, including allergies to any of the components of the investigational product and/or clinically significant food allergies as determined by the investigator; * Presence or history of any significant cardiovascular, gastrointestinal, hepatic, renal, pulmonary, hematologic, endocrine, immunologic, dermatologic, neurologic, or psychiatric disease, as determined by the investigator; * Presence of any other condition (including surgery) known to interfere with the absorption, distribution, metabolism, or excretion of medicines. * Requirement for any over-the-counter and/or prescription medication, vitamins, and/or herbal supplements on a regular basis. * Use of any medications (over-the-counter and/or prescription medication), vitamins, and/or herbal supplements, within the 30-day period prior to study drug administration or within 5 half-lives (if known), whichever is longer. * Recent (6-month) history of drug or alcohol abuse. * Positive test result for hepatitis B surface antigen (HBsAg), hepatitis C virus antibody (HCV Ab), or HIV antibodies (HIV Ab) at screening. * Donation or loss of 550 mL or more blood volume (including plasmapheresis) or receipt of a transfusion of any blood product within 8 weeks prior to study drug administration. * Receipt of any investigational product within a time period equal to 10 half-lives of the product, if known, or a minimum of 30 days prior to study drug administration. * Positive screen results for drugs of abuse, alcohol, or cotinine at screening or Day -1. * Consumption of alcohol within 72 hours prior to study drug administration. * Consumption of grapefruit, grapefruit products, star fruit, star fruit products, or Seville oranges within the 72-hour period prior to study drug administration. * Use of tobacco or nicotine-containing products within the 6-month period preceding study drug administration. * Current enrollment in another clinical study. * Previous enrollment in this study. * Screening laboratory analyses that show any of the following abnormal laboratory results: 1. Alanine transaminase (ALT) level above 1.2× the upper limit of normal (ULN). 2. Aspartate transaminase (AST) level above 1.2× the ULN. 3. Any other laboratory results that are outside of the laboratory normal reference range and considered clinically significant by the investigator. * Clinically-significant abnormal ECG; ECG with QTc using Fridericia's correction formula (QTcF) \> 450 msec is exclusionary. * Consideration by the investigator, for any reason, that the subject is an unsuitable candidate to receive RTA 901.