Condition category
Digestive System
Date applied
08/01/2008
Date assigned
30/01/2008
Last edited
17/10/2012
Prospective/Retrospective
Retrospectively registered
Overall trial status
Stopped
Recruitment status
Stopped

Plain English Summary

Not provided at time of registration

Trial website

Contact information

Type

Scientific

Primary contact

Prof Richard Logan

ORCID ID

Contact details

Division of Epidemiology and Public Health
Queens Medical Centre
Nottingham
NG7 2UH
United Kingdom
+44 (0)115 823 0452
Richard.Logan@nottingham.ac.uk

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

N/A

Study information

Scientific title

A randomised, open study of aminosalicylate withdrawal in patients with ulcerative colitis in established remission on combination treatment of azathioprine (or 6-mercaptopurine) and an aminosalicylate

Acronym

CASA

Study hypothesis

To investigate whether azathioprine alone is as effective as azathioprine and a 5-aminosalicylic acid (5-ASA) compound in maintaining recently established remission in patients on both drugs.

Ethics approval

Ethics approval received from the Cambridgeshire 4 Research Ethics Committee (REC) (formerly Eastern MREC) on the 15th September 2005.

Study design

This will be a randomised, open, multi-centre, withdrawal study. There will be two phases: phase 1, the primary outcome measure over one year, and phase 2, ongoing follow-up out to 3 years.

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Hospitals

Trial type

Treatment

Patient information sheet

Condition

Ulcerative colitis

Intervention

Please note that this study was stopped in 2008 due to poor recruitment.

At enrolment patients (already taking azathioprine and a 5-ASA) will have bloods taken and have a sigmoidoscopy to confirm remission. They will then be randomised to:
1. Mono-therapy (i.e. withdraw their existing 5-ASA and take azathioprine only)
2. Dual-therapy (i.e. continue as normal on azathioprine and their existing 5-ASA)

They will remain on their randomised therapy for 12 months, after which the clinician will review their treatment. Patients will be followed up every 3 months by either telephone contact or clinic visit. Their blood results, which are done every 2 - 3 months by routine NHS azathioprine blood monitoring, will be recorded as part of the study. They will also be followed up after 24 months and 36 months by clinic visit.

Intervention type

Drug

Phase

Not Specified

Drug names

Azathioprine (or 6-mercaptopurine), 5-aminosalicylic acid

Primary outcome measures

Relapse rates of azathioprine mono-therapy compared to azathioprine and salicylate dual therapy over the first 12 months.

Secondary outcome measures

Factors predictive of success of the different treatment regimes.

Overall trial start date

01/02/2006

Overall trial end date

31/12/2009

Reason abandoned

Participant recruitment issue

Eligibility

Participant inclusion criteria

1. Male and female patients aged between 18 and 75 years with ulcerative colitis
2. Patients whose ulcerative colitis has been in clinical remission, defined as being off steroids for 3 months or longer
3. Patients taking both azathioprine (or 6-mercaptopurine) and an aminosalicylate
4. Patients taking azathioprine (greater than 50 mg/day) or 6-mercaptopurine (greater than 25 mg/day) at a stable dose for at least 8 weeks
5. Patients taking an aminosalicylate at a stable dose (specified below) for at least 4 weeks:
5.1. Sulphasalazine greater than 1.5 g/day
5.2. Pentasa (slow release mesalazine) greater than 750 mg/day
5.3. Asacol (mesalazine) or generic equivalents greater than 800 mg/day
5.4. Colazide (balsalazide) greater than 2.25 g/day
5.5. Dipentum (olsalazine) greater than 750 mg/day
6. Patients on combined treatment with azathioprine (or 6-MP) and an aminosalicylate for a minimum of 6 months but no more than 4 years without relapse. Patients may enter if they have briefly been off either treatment during this time (e.g., because of abnormal blood test results) but prescription of each drug should cover at least 85% of the period of time for continuous drug treatment to be declared. N.B. Duration of aminosalicylate may be longer.
7. Patients who have given written informed consent

Participant type

Patient

Age group

Adult

Gender

Both

Target number of participants

410 (less than 40 were recruited by the time the trial was stopped)

Participant exclusion criteria

1. Patients with Crohn’s disease
2. Patients with a baseline Walmsley Simple Activity Index greater than 2
3. Patients with a baseline sigmoidoscopy grade of greater than 2 (Baron Scale)
4. Patients requiring long term treatment with oral steroids for any medical condition
5. Women who are pregnant or lactating
6. Patients with known human immunodeficiency virus (HIV) infection
7. Other serious medical or psychiatric illness currently ongoing, or experienced within the past three months, that in the opinion of the investigator would compromise the study
8. Patients unable to comply with the protocol requirements, including severe alcohol and drug use

Recruitment start date

01/02/2006

Recruitment end date

31/12/2009

Locations

Countries of recruitment

United Kingdom

Trial participating centre

Division of Epidemiology and Public Health
Nottingham
NG7 2UH
United Kingdom

Sponsor information

Organisation

University of Nottingham (UK)

Sponsor details

Research Innovation Services
King's Meadow Campus
Lenton Lane
Nottingham
NG7 2NR
United Kingdom
+44 (0)115 951 5679
paul.cartledge@nottingham.ac.uk

Sponsor type

University/education

Website

http://www.nottingham.ac.uk/

Funders

Funder type

Charity

Funder name

Moulton Charitable Foundation (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes