Pentasa Once Daily in Ulcerative Colitis for Maintenance of Remission

Inclusion Criteria:

1. Patients have an established diagnosis of ulcerative colitis and are in clinicalremission with an UC-DAI < 2 at enrollment

2. Extension of the disease > 15 cm distance from anal verge

3. Patients who have had a clinical relapse within the past year. Clinical relapse isdefined as activity of the disease for which maintenance therapy had to be adjusted.

4. Patients on oral mesalazine maintenance therapy ≤ 2.5 grams per day

5. 18 years or older

6. Signed informed consent

Exclusion Criteria:

1. Patients with evidence of other forms of inflammatory bowel disease, idiopathicproctitis or infectious disease

2. Patients allergic to acetylsalicylic acid and other salicylate derivates aspirin orsalicylates derivatives

3. Patients who used mesalazine > 2.5 grams orally in the previous month,

4. Patients who used rectal mesalazine > 3 grams per week in the previous month

5. Use of corticosteroids (oral and/or rectal routes) within the last month

6. Intake of immunosuppressants within the last 3 months

7. Patients with (known) significant hepatic (up to 2 x upper limit of normal) or (known)renal function abnormalities, to 1.5 x upper limit of normal values

8. Patients with history or physical examination findings indicative of active alcohol ordrug abuse

9. Patients with a history of disease, including mental/emotional disorders, that wouldinterfere with their participation in the study

10. Women who are pregnant or nursing (non-menopausal women who are sexually active and donot use effective contraceptives, as judged by the investigator, must have a negativepregnancy test)

11. Patients who participated in another clinical study in the last 3 months

12. Patients who were previously participating in this study

13. Patients with any other disease that may influence the study assessment, such asmalignant disease, etc.

14. Patients who are unable to comply with any requirements of the protocol

15. Patients who are unable to write or read local language.