Oral OKT3 for the Treatment of Active Ulcerative Colitis

Ulcerative colitis (UC) is a chronic disease of unknown etiology characterized by infiltration of inflammatory cells into the intestinal tract. OKT3 is an approved drug for intravenous use in the treatment of solid-organ transplantation. However, intravenous dosing has been limited by significant toxicities. Data from animal models suggest that antibody recognizing the T3 antigen complex Cluster of Differentiation 3 (anti-CD3) administered via the oral route is effective at treating a variety of autoimmune diseases. No side effects were observed in a recent phase I study of healthy participants receiving oral anti-CD3 monoclonal antibody (mAb). The objectives of the current study are to assess the safety, immunologic effects and efficacy of short-term oral administration of OKT3 in participants with active ulcerative colitis. OKT3 will be delivered orally as a 1 milligram (mg) or 2 mg dose with Omeprazole 20 mg daily for 30 consecutive days in an open-label pilot trial. Thirty two participants will be screened for a targeted completion of 16 enrolled participants. The participants will be evaluated at baseline, day 1, day 2, week 1, week 3, as well as after completion of therapy at week 5 and 10 after the initiation of treatment. Lab tests will be performed at screening, baseline, day 2, week 1, week 3, week 5 and week 10. Clinical data will be collected at all study visits and via diary entries throughout the study period. A flexible sigmoidoscopy will be done at baseline and at week 5. Stool studies will be performed at screening to rule out infection. To be eligible for this study, participants must be between the ages of 18 and 65 years and have a history of moderately to severely active UC as defined by a Mayo score of 6 to 12. They may not be taking concurrent biologic or immunomodulator therapy for UC.