Long-Term Safety and Tolerability of Mesalamine Pellets in Participants With Ulcerative Colitis in Remission

Inclusion Criteria:

1. An Institutional Review Board (IRB)/Ethics Committee (EC) approved informed consent issigned and dated prior to any study-related activities.

2. Participant has successfully participated in a previous MP clinical study perinvestigator's discretion with successful participation minimally defined as compliantwith study-related procedures and study drug dosing schedule in the previous study anddid not discontinue from the previous study due to study drug-related AE(s) or if newparticipants: a. Participant is a male or, If the participant is female, she is eligible to enter if she is of: Non-childbearing potential (that is; physiologically incapable of becoming pregnant,including any female who has undergone sterilization [hysterectomy or bilateral tuballigation] or is post-menopausal. For purposes of this study, postmenopausal is definedas 1 year without menses); or childbearing potential, has a negative serum pregnancytest at screen and, if heterosexually active, agrees to one of the following: i) Double barrier method of contraception, specifically, use of a condom andspermicide, for 1 week prior to study drug administration, throughout the 6-monthTreatment Phase, and the 2-week follow-up phase. ii) Oral contraceptives administered for at least 2 monthly cycles prior to study drugadministration during all 6 months of study drug administration and administered for 1monthly cycle following completion of the study. iii) An intrauterine device (IUD), inserted by a qualified clinician, with publisheddata showing that the lowest expected failure rate is less than (<)1% per year (notall IUDs meet this criterion). iv) Medroxyprogesterone acetate (DEPO-PROVERA) administered for a minimum of 1 monthlycycle prior to the study drug administration, during all 6 months of study drugadministration, and administered for 1 monthly cycle following study completion.Norelgestromin/ ethinyl estradiol transdermal system (Ortho Evra patch) administeredfor at least 2 monthly cycles prior to study drug administration and administered for 2 monthly cycles following study completion. v) Partner has undergone vasectomy and participant is in a monogamous relationship. The investigator is responsible for determining whether the participant has adequatebirth control for study participation. b. Participant is greater than or equal to (≥) 18 years of age. c. Participant hashistorically confirmed diagnosis (physician letter for newly/recently diagnosed and bymedical records for previously diagnosed participants) of mild to moderate UC inremission for greater than (>) 1 month and <12 months. d. Confirmed current remission defined as both: A screening rectal bleeding score of 0as described in the Disease Activity Index (DAI) (Sutherland Index) where 0 = None Ascreening sigmoidoscopy score of 0 to 1 for mucosal appearance as described in the (Sutherland Index where 0 = intact mucosa with preserved or distorted vessels and 1 =Erythema, decreased vascular pattern, granularity, no mucosal hemorrhage.

3. Participant and investigator consider there is the potential for benefit to theparticipant with MP treatment.

4. Participant is capable and willing to comply with all study procedures.

Exclusion Criteria:

1. Participant has any condition or circumstance that would, in the opinion of theinvestigator, prevent completion of the study or interfere with analysis of studyresults, including history of noncompliance with treatments or visits. If a new participant, the following additional exclusion criteria will apply:

2. Participant has a history of allergy or intolerance to aspirin, mesalamine or othersalicylates.

3. Participant has an abnormal clinical lab result which in the opinion of theinvestigator is significant enough to prevent participant's enrollment in the study.

4. Participant or participant's parents are known to have phenylketonuria.

5. Participant has participated in an investigational drug or device study within the 30days prior to study screening.

6. Participant shows evidence of current excessive alcohol consumption or drugdependence.

7. Participant has uncontrolled, clinically significant renal disease manifested by 1.5 *ULN of serum creatinine or blood urea nitrogen (BUN) levels.

8. Participant has calculated creatinine clearance level of <60 mL/min