The purpose of this study is to evaluate the safety, tolerability and pharmacokinetics of ARC-520 in normal, adult volunteers.

Key Inclusion Criteria:

• Healthy male or female subjects, 18-55 years of age
• Be a non-smoker

Key Exclusion Criteria:

• History of clinically relevant medical illnesses that in the Investigator opinion may jeopardize subject safety or interfere with participation in the study, including but not limited to hematological, renal, endocrine, pulmonary, gastrointestinal, cardiovascular, hepatic, psychiatric, neurologic, or allergic disease
• Acute signs of hepatitis/other infection (e.g., moderate fever, jaundice, nausea, vomiting, abdominal pain) evident within 4 weeks of screening and/or at the screening examination.
• Use of any drugs known to induce or inhibit hepatic drug metabolism within 30 days prior to administration of study treatment.
• Is sero-positive for HIV, HBV, HCV, and/or a history of delta virus hepatitis.
• Currently uses and/or has a history of alcohol and/or drug abuse < 12 months from screening.
• Use of investigational agents or devices within 30 days prior to planned study dosing or current participation in an investigational study.