This is a single and multiple ascending dose study in healthy male and female (of non-child bearing potential) Japanese and White volunteers, to assess the safety, tolerability, and blood and urine drug levels of FosD. FosD is being developed for the treatment of rheumatoid arthritis.

Inclusion Criteria:

• Healthy male and female (of non-childbearing potential) Japanese subjects and White subjects (origins in Europe, the Middle East, or North Africa)
• Body mass index (BMI) between 17 and 27 kg/m2 and weigh at least 45 kg and no more than 100 kg

Exclusion Criteria:

• History or presence of respiratory, GI, renal, hepatic, hematological, lymphatic, neurological, cardiovascular, psychiatric, musculoskeletal, genitourinary, immunological, dermatological, connective tissue diseases or disorders
• Any clinically significant illness, acute infection, known inflammatory process, medical/surgical procedure or trauma within 4 weeks of the first administration of investigational product
• Smoking in excess of 5 cigarettes per day or equivalent within 30 days of Day 1
• Use of prescription or over-the-counter drugs within 2 weeks of first administration of investigational product