The purpose of this study is to determine the safety, tolerability, pharmacokinetics and pharmacodynamics of ALN-TTRSC (revusiran) in healthy volunteer subjects.

Inclusion Criteria:

• Body mass index (BMI) must be ≥ 16.5 kg/m2 and ≤ 35.0 kg/m2;
• Female subjects must be of non-childbearing potential; e.g., postmenopausal or pre-menopausal with surgical sterilization;
• Male subjects agree to use appropriate contraception;
• Adequate blood counts, liver and renal function;
• Non-smokers for at least 3 months;
• Willing to give written informed consent and are willing to comply with the study requirements;
• Subject was born in Japan and has lived outside of Japan for <10 years, and subject's biological parents and grandparents are fully Japanese and were born in Japan (cohorts 19 and 20).

Exclusion Criteria:

• Known human immunodeficiency virus (HIV) positive status or known or suspected systemic bacterial, viral, parasitic, or fungal infection;
• Subjects with a history of multiple drug allergies or intolerance to SC injection;
• History of drug abuse and/or alcohol abuse;
• Receiving an investigational agent within 3 months prior to study drug administration;
• Considered unfit for the study by the Principal Investigator.