The purpose of this study is to evaluate the disease-drug-drug interaction (DDDI) potential of afimkibart (also known as RO7790121). This will be assessed by the characterization of the pharmacokinetics (PK) of cytochrome P450 (CYP) enzyme substrates alone and after administration of afimkibart in participants with moderately to severely active ulcerative colitis (UC).
Body weight >= 40kg
Agreement to adhere to the contraceptive requirements
Confirmed diagnosis of UC with supportive clinical, endoscopic, and histopathological evidence
Active UC confirmed by endoscopy (flexible sigmoidoscopy or colonoscopy) extending >=15 cm from the anal verge
Current diagnosis of Crohn's disease (CD),abdominal/intrabdominal/perianal fistula and/or abscess, indeterminant colitis, IBD-unclassified, microscopic colitis, ischemic colitis, infectious colitis, radiation colitis, or active diverticular disease
Presence of an ostomy or ileoanal pouch
Current diagnosis or suspicion of primary sclerosing cholangitis
Lack of peripheral venous access