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Clinical DrugTrials

in Inflammatory Bowel Disease (IBD)

Why and how are clinical drug trials done in IBD?

  • There is a need for new drug treatments in IBD. Even with all the advances in new drugs available of late, there are still many patients who do not respond to these drugs; and there are also many patients who initially respond and then lose response and flare with active disease and need new drug treatments.

  • Any drugs developed in the past 20 years and brought to market to treat IBD have been developed through clinical drug trials.

  • Most clinical drug trials are conducted by drug companies. They conduct research and development of new drugs, many of which do not make it into clinical drug trials.

  • When drugs make it into clinical drug trials, these studies require a large staff involved in the clinical trial and often several centres where patients get enrolled in the trial. Each clinical trial typically costs millions of dollars.

  • When a centre signs on to participate in a clinical trial they sign a contract to enroll some patients and also to follow the rules of the clinical trial. Each clinical trial will have one set of rules and every participating centre must follow the same rules

  • Each centre will submit the outline and rules of the clinical trial to a Research Ethics Board. This is an independent group that will review the study to ensure that it is safe and to ensure the study investigators follow the rules of the study. The primary purpose of having the study reviewed by a Research Ethics Board is to ensure the safety of any patients who choose to participate and ensure their health information is kept private and safe.

  • When patients choose to participate in a clinical drug trial it is always voluntary. This means it is the patient’s choice to enroll and also it is their choice if they want to withdraw from the study at any time.

  • There are many rules of clinical drug trials and they include the following:

    • What type of patients can be enrolled. This includes what type of disease they have and how active the disease needs to be.

    • What procedures need to be undertaken throughout the trial. This includes whether endoscopies need to be done and what type of x-rays, blood, urine and/or stool tests need to be done. There are also rules as to how often these tests need to be done. For example, it is common for clinical drug trials in ulcerative colitis to require a lower endoscopy at the time of enrollment and at 8 weeks after receiving the first dose of study drug

    • How often the study visits will be undertaken

    • There are rules as to what happens if the person enrolled has any side effects, new symptoms that arise during the study or when a  person withdraws from the study

  • Clinical trial centres get paid money from the sponsoring drug company to conduct the trial in their centre. These centres need the money to cover the expenses of the trial and also may have left over money they earn by conducting the trial

  • Some clinical trials are initiated by doctor investigators and not by pharmaceutical companies

  • Most clinical trials are done in more than one centre and some are done in many centres including in North America, South America, Europe and Asia at the same time.

Words used in clinical drug trials

  • Placebo - placebo refers to an inert drug; that means that it doesn’t have specific activity against what is being treated. However, in all clinical drug trials that include some people getting placebo, there is a still a percentage of people that respond to placebo. It is not fully understood why this occurs.

  • Placebo controlled  - this means that one group of patients in the study will get placebo treatment for some duration of the study

  • Randomization - This is the act of assigning patients to one type of treatment versus the other. The process of randomization requires every enrolled person to have an equal chance of getting placed into any one of the treatment possibilities in the study

  • Blind - This refers to people either running the study or participating in the study being unaware of what treatment the individual has been assigned to. Double blind means that both the study investigator and the patient in the study do not know the treatment assignment is. Others involved in the study may be monitoring for safety (e.g. research nurse or pharmacist)

  • Monoclonal antibody - An antibody is a protein that can bind to another protein making the second protein ineffective. In the case of IBD, antibodies are administered against proteins that are active in the inflammatory response in IBD. A monoclonal antibody means that the antibody is made to act against a single specific protein.

  • Disease activity index - this is a collection of items that addresses the symptoms and inflammation of the IBD. These indices are used in clinical drug trials as measures to follow to determine if the drug was effective in the study.

  • Remission - This is an outcome from the study where the patient in the study feels near normal or normal and measures of inflammation in the study have returned to normal.

  • Response - This is an outcome from the study where the patient feels much better but not normal and the measures of inflammation in the study have improved but have not returned to normal.

  • Phase I trial - this is a drug trial where a small number of patients are enrolled and the purpose is to determine that the drug being studied is safe

  • Phase II trial - this is a drug trial when patients get randomized to one type of treatment versus another or versus placebo. The purpose is to determine if the drug is effective in the disease understudy and often the purpose may be to determine the most effective dose of the drug

  • Phase III trial - this is a drug trial where the drug is studied in different doses and sometimes against placebo and sometimes against the currently available treatments. These are the trials that could get the drug approved by national regulatory authorities



Last reviewed: March 2020

Special thank you to Dr Peter Thomson, Department of Pharmacy Shared Health and University of Manitoba for assistance with this Fact Sheet.

For more information and fact sheets about IBD and its treatment please visit:

Disclaimer: This information is provided for educational purposes only. Always consult a qualified health care professional for your specific care.

Source: This summary provides scientifically accurate information.  It was prepared in a research review by researchers with the IBD Clinical and Research Centre, University of Manitoba with assistance from colleagues in Canada and internationally. 


Acknowledgement:  Preparation of this material was supported by funding from the Canadian Institutes of Health Research. 

©2017 Charles N. Bernstein, John R. Walker on behalf of Manitoba IBD Clinical and Research Centre. This work is licensed under a Creative Commons Attribution-nonCommercial-NoDerivs 2.5 Canada License.  You are free to copy and distribute this material in its entirety as long as: 1) this material is not used in any way that suggests we endorse you or your use of the material, 2) this material is not used for commercial purposes, 3) this material is not altered in any way (no derivative works). View full license at

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