This multiple-center, nonrandomized, open label, parallel group, single dose study will be conducted in male and female subjects with normal hepatic function or moderate (Child-Pugh Class B) hepatic impairment to evaluate the effect of hepatic impairment on the pharmacokinetics (PK) of TD-4208.

Inclusion Criteria:

• For hepatic impairment group: Subject has moderate hepatic impairment (Child Pugh B)
• For normal hepatic function group: Subject is in good health

Exclusion Criteria:

• Women who are pregnant, lactating, breastfeeding, or planning to become pregnant during the study.
• Subject has received an investigational drug (or medical device) within 30 days
• Subject who, for any reason, is deemed by the investigator to be inappropriate for this study; or has any condition that would confound or interfere with the evaluation of the safety, tolerability, or PK of the investigational drug; or is unable to comply with the study protocol.