Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of AMG 181 in Healthy Subjects and Subjects with Mild to Moderate Ulcerative Colitis

Healthy Volunteers - Healthy male or female subjects of non-reproductive potential between 18 to 45 year-of –age - Body Mass Index (BMI) between 18 and 34 kg/m2 - Normal physical and neurological examination, clinical laboratory values and ECG - Additional inclusion criteria apply Inclusion Criteria: Subjects with Mild to Moderate Ulcerative Colitis - Male or female subjects between 18 to 55 year-of –age - Body Mass Index (BMI) between 18 and 34 kg/m2 - Diagnosis of Ulcerative Colitis for at least 2 months - Active, mild to moderate disease as defined by an Ulcerative Colitis Disease Activity Index (UCDAI, aka Mayo score) score of 4 to 9 (inclusive), with a minimum sigmoidoscopy score of 1 - Additional inclusion criteria apply

Healthy Volunteers - History or evidence of a clinically significant disorder (including psychiatric), condition or disease that would pose a risk to subject safety or interfere with the study evaluations, procedures or completion - History of malignancy of any type, other than in situ cervical cancer or surgically excised non-melanomatous skin cancers within the past 5 years - Recent or on-going infection(s) - Underlying condition(s) that predisposes the subject to infections - Additional exclusion criteria apply Exclusion criteria: Subjects with Mild to Moderate Ulcerative Colitis - Disease limited to the rectum, i.e. within 20 cm of the anal verge - Any prior gastrointestinal surgery - Evidence of severe disease (as evidenced by an Hb concentration <11g/dL; toxic megacolon, or an UCDAI score≥10) - Immunosuppressive therapy with either azathioprine, methotrexate, or mercaptopurine, within the past 3 months - Prior exposure to a biologic agent or cyclosporine A - Use of antibiotics within the past 2 weeks of screening and during screening period - Use of topical (e.g. suppository or enema) mesalamine or steroids within two weeks prior to day 1 - Additional exclusion criteria apply