Mesalazine Monotherapy vs Continuing Thiopurines in Older Patients with Ulcerative Colitis in Long-Term Remission

3 1 1 1

What is this study about?

This study is being done in older people with Ulcerative Colitis who have been in long-term remission, which means the disease has been quiet for a long time. The purpose of the study is to compare two ways of treating the disease: stopping thiopurines, which are medicines that reduce the immune system’s activity, and continuing treatment, with a switch to mesalazine alone. Mesalazine is an anti-inflammatory medicine used by mouth and may be given as tablets or prolonged-release granules under names such as Salofalk, Pentasa, Asacol, and Claversal.

People in the study are placed into one of the treatment approaches and then followed over time for about 24 months. During this period, regular check-ups are used to watch for signs that Ulcerative Colitis may be becoming active again, and to monitor safety, side effects, hospital stays, surgery to remove the colon, and death. The study also looks at how well the treatment is taken as prescribed.

Ulcerative Colitis is a long-lasting disease that causes swelling and sores in the large bowel, also called the colon. When the disease becomes active again after a quiet period, this is called a relapse or recurrence. Thiopurines are medicines that lower immune system activity to help control the disease, while mesalazine helps reduce swelling in the bowel.

Who Can Join the Study?

Be 60 years of age or older.
Have a confirmed diagnosis of ulcerative colitis according to accepted ECCO criteria (medical guidelines used to diagnose this condition).
Have taken azathioprine (a medicine that lowers immune activity) at 1 to 2.5 mg per kg per day or mercaptopurine at 0.75 to 1.5 mg per kg per day for at least 5 years in a row.
Have been on a stable dose of azathioprine or mercaptopurine for the last 12 months, meaning the dose has stayed at the lowest effective amount without side effects.
If also taking oral mesalazine (a medicine taken by mouth to reduce inflammation in the bowel), have been on a stable dose for the last 12 months.
Have had clinical remission for at least 3 years, meaning no flare-ups requiring systemic corticosteroids (steroid medicines taken by mouth or through a vein) or biologic medicines (treatments made from living cells that target the immune system).
May still use a stable dose of oral mesalazine and/or topical rectal treatments (medicines placed in the rectum, the last part of the bowel), as long as the dose has not changed in the last 12 months.
Have objective clinical remission at the study entry visit, shown by a Partial Mayo score of 2 or less, with the rectal bleeding score equal to 0. The Partial Mayo score is a doctor-assessed measure of disease activity.
Have had a colonoscopy (a camera test of the large bowel) within the last 12 months showing endoscopic remission, with an endoscopic Mayo score of 0, meaning no visible inflammation.
Have subclinical inflammatory remission, meaning no sign of hidden inflammation, shown by a faecal calprotectin level of 150 mg/kg or lower about 1 month before randomisation. Faecal calprotectin is a stool test that helps measure bowel inflammation.
Be willing and able to give written informed consent, which means signing a form to show agreement to join the study after understanding it.

Who Cannot Join the Study?

You cannot join if you have ulcerative proctitis, which means the inflammation has only affected the last part of the large bowel and the affected area has been shorter than 25 cm during the course of the illness.
You cannot join if you have had a total or segmental colectomy, meaning surgery to remove all or part of the large bowel.
You cannot join if you have an ileoanal reservoir, which is a surgically created pouch that connects the end of the small bowel to the anus.
You cannot join if you have a history of complex perianal disease, meaning serious or difficult disease around the area of the anus.
You cannot join if you cannot tolerate oral 5-ASA, a medicine taken by mouth that is used to treat bowel inflammation.
You cannot join if you are now using, or have used in the past, any selective immunomodulator or any advanced therapy approved for ulcerative colitis. These are medicines that change how the immune system works or newer special treatments for the disease.
You cannot join if you stopped topical treatment such as mesalazine or steroids within the last 3 months. Topical treatment means medicine used locally, usually as a suppository, enema, or rectal foam.
You cannot join if you have chronic kidney failure with creatinine of 2 mg/dL or more, or if your kidney filtering rate is 30 mL/min/1.73 m² or less. Creatinine is a blood test that helps show how well the kidneys are working.
You cannot join if your liver blood tests are abnormal, meaning AST, ALT, alkaline phosphatase, or GGT are more than 2 times the upper limit of normal. These tests help show how well the liver is working.
You cannot join if your blood counts are too low at the time of inclusion: neutrophils below 1500 cells/mm³, lymphocytes below 500 cells/mm³, platelets below 120,000 cells/mm³, or hemoglobin below 12 g/dL for women or 13 g/dL for men. Neutrophils and lymphocytes are types of white blood cells, platelets help blood clot, and hemoglobin carries oxygen in the blood.

Where you can join this trial?

Verified and Recommended Sites

No sites found in this category

Verified Sites

No sites found in this category

Other Sites

Site Name	City	Country
Consorci Sanitari Del Maresme	Mataró	Spain
Virgen del Rocío University Hospital	Sevilla	Spain
Hospital Clinic De Barcelona	Barcelona	Spain
Universidade De Santiago De Compostela	Santiago De Compostela	Spain
Hospital Universitari De Girona Doctor Josep Trueta	Girona	Spain
Fundacio Assistencial De Mutua De Terrassa Fpc	Terrassa	Spain
Hospital Alvaro Cunqueiro	Vigo	Spain
Area De Salud De Burgos Y Soria	Burgos	Spain
Hhtxwawe Udwdqlsyarasy Mlkydmn Dj Vfsskpzndo	Santander	Spain
Pero Tcpcj Htygxred Ucpmlbwprlpv	Sabadell	Spain
Fginprvck Pktu Lr Iggurtwdubrui Bcwjsxefs Dqx Hrkthfhl Ulemoqqtmwqvg Lu Pmk	Madrid	Spain
Hxiddish Uqpnuvqaqogfk Hdifsikx Tdwch y Pnaqre Ilsexvjk Cylwqq dkwhtxunlxcnvvykq (eglm	Badalona	Spain

Trial status

Country	Status	Recruitment Start
Spain	Not yet recruiting	01.05.2026

Trial locations

Investigated drugs:

Mesalazine

Mesalazine is the main study medicine in this trial. It is taken by mouth and comes as tablets or granules that release the medicine slowly or protect it from stomach acid. It is used to help keep ulcerative colitis under control and to lower the chance of the disease becoming active again after thiopurines are stopped. In this study, it is being used as the treatment patients switch to or continue as a single medicine to help maintain remission.

Ulcerative Colitis – Ulcerative colitis is a long-term disease that causes ongoing inflammation of the large intestine and rectum. It usually develops in episodes, with periods of calm disease followed by flare-ups. Over time, the inflammation can return after a quiet period and may spread more widely within the colon. Symptoms and disease activity can change gradually, with some people remaining stable for long periods and others having repeated relapses.

Trial ID:

2025-524675-23-00

Protocol code:

IDEA

NCT ID:

NCT07248644

Trial Phase:

Therapeutic confirmatory (Phase III)

Other Trials to Consider

#1 Clinical Trials Search in Europe

Mesalazine Monotherapy vs Continuing Thiopurines in Older Patients with Ulcerative Colitis in Long-Term Remission

What is this study about?

Who Can Join the Study?

Who Cannot Join the Study?