This is a drug interaction study evaluating the pharmacokinetic profiles of Sulfamethoxazole administered alone & in combination with Multi MatriX system (MMX®) formulation of mesalazine/mesalazine (Lialda®; Mesavancol®; Mezavant®) (MMX Mesalazine/mesalamine).

Inclusion Criteria:

1. Age 18-55 years inclusive at the time of consent. The date of signing informed consent is defined as the beginning of the Screening Period.

2. Subject is willing to comply with any applicable contraceptive requirements of the protocol and is:

   • Male, or
   • Non-pregnant, non-lactating female
   • Females must be at least 90 days post-partum or nulliparous.

Exclusion Criteria

1. A history of current or recurrent disease that could affect the colon. This includes gastrointestinal disease, peptic ulceration, gastrointestinal bleeding, celiac disease, lactose intolerance, ulcerative colitis, Crohn's disease, or Irritable Bowel Syndrome. Subjects who have a history of chronic constipation, which is physician diagnosed and treated, will also be excluded from the study (frequency of bowel movements >48 hours between samples).
2. A history of current or relevant serious, severe, or unstable (acute or progressive) physical or psychiatric illness.
3. A history of gastrointestinal surgery performed within the past 12 months prior to the first dose of investigational product, with the exception of an appendectomy.
4. A history of or current clinically relevant moderate or severe renal or hepatic impairment.
5. A history of asthma or bronchospasm associated with the use of 5-ASA or other non-steroidal anti-inflammatory drugs.
6. Known or suspected intolerance or hypersensitivity to the investigational product or sulfamethoxazole/trimethoprim, closely related compounds, or any of the stated ingredients
7. A history of, or current, pancreatitis