A Phase 2 Study of Interferon Beta-1a (Avonex®) in Ulcerative Colitis

Key Inclusion Criteria

• Established diagnosis of ulcerative colitis (UC) for ≥6 months
• 20 cm active disease at Screening endoscopy
• Must have active UC with a Mayo Score/Disease Activity Index (DAI) of 6 to 13 points and moderate to severe disease on endoscopy (Mayo endoscopic score of at least 2) despite prior or concomitant treatment
• Colonoscopy within past 5 years for extent of disease and to exclude polyps
• For subjects with UC for more than 10 years, colonoscopy with appropriate biopsies within 1 year prior to Screening to exclude dysplasia and neoplasia.
• Must be willing and able to practice effective birth control during the study and for 1 month after the last dose of study treatment.

Key Exclusion Criteria

• Diagnosis of indeterminate colitis or Crohn's disease
• Need for imminent surgery
• Diagnosis of primary sclerosing cholangitis or toxic megacolon
• Hemoglobin ≤9 g/dL
• White blood cell count < 3500 cells/mm^3
• Lymphocyte count <1000 cells/µL
• Platelet count <100,000 cells/µL
• Female subjects who are pregnant or who wish to become pregnant during the study, or who are lactating
• Known symptomatic colonic stricture
• Stool cultures positive for enteric infection
• History of malignant disease
• History of major abdominal surgery (e.g., gastrectomy) within past 5 years
• History of small bowel or colonic obstruction or resection
• History of drug or alcohol abuse (as defined by the Investigator) within 2 years prior to Screening
• Use of anti-diarrheal agents during the screening period
• Previous participation in this study
• Previous treatment with interferon beta or other interferon products

NOTE: Other protocol defined Inclusion/Exclusion criteria may apply.