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A surgical operation for ulcerative colitis (UC) after removal of the bowel. An internal pouch is made from the ileum and attached to the anus. This means stools are passed through the anus in the usual way. Sometimes referred to as restorative proctocolectomy.

Immune system

The network of cells, tissues, and organs that work together to protect the body and defend it against infectious organisms (bacteria, viruses, etc.) and other harmful substances. Through a series of steps called the immune response, the immune system attacks these organisms and substances.


Suppression of the immune system and its ability to fight infection. Immunosuppression may be due to drugs or diseases.

Inclusion/exclusion criteria

The medical or social standards that determine whether a person can or cannot enter a clinical trial. These criteria are based on factors such as age, gender, the type and stage of a disease, previous treatment history, and other medical conditions. Inclusion and exclusion criteria are not used to reject people personally but rather to identify appropriate patients and keep them safe.


Used to relieve moderate to severe pain, tenderness, swelling, and stiffness caused by osteoarthritis (arthritis due to a breakdown of the lining of the joints), rheumatoid arthritis and ankylosing spondylitis.

Induction phase

The initial treatment given for a disease. Generally, it is part of a standard set of treatments, such as surgery followed by chemotherapy and radiation.


Infections are caused by germs inside the body. Different types of infections include colds, sore throats, rashes, and cuts or wounds that become infected. How they are treated depends on what type of germ caused the infection.


Can be transmitted through the environment, and can spread infection.


Inflammation is a natural process that the body normally uses to protect itself from harm, such as an injury or infection. Affected areas may become red, swollen and painful, and feel hot or warm to the touch.

Inflammatory breast cancer

This type of breast cancer begins in the breast ducts. The cancer cells spread from the ducts to the lymph vessels in the skin of the breast.

Inflammatory disease

A disease characterized by inflammation, where the body’s immune system thinks its own cells are threats, attacking them as they would typically target external threats like foreign bacteria or a virus.

Informed consent

The process of learning the key facts about a clinical trial before deciding whether or not to participate. In order to help patients make that decision, the doctors and nurses involved in the trial explain the study in detail. The study team must also provide any new information to the patient as it becomes available. Informed consent is therefore an ongoing process.


A method of administering fluids, including drugs, into the bloodstream. Also referred to as intravenous infusion.


A hormone, produced by the beta cells of the islets of Langerhans of the pancreas, that regulates the metabolism of glucose and other nutrients.

Interim analysis

The early analysis of data accumulated before all the patients have completed the study. This can serve to detect trends that might justify modification of the protocol, or a change in the type or format of data being collected. These analyses can also be used in scientific publications to reveal early trial results to the scientific community (other researchers and doctors).

Intervention model

The general design describing how interventions will be assigned to participants in a clinical study. Types of intervention models include single group design, parallel design and crossover design. An intervention can include participants receiving drugs, medical devices, procedures, vaccines, other investigational or available products, or non-invasive approaches like surveys, education or interviews.


The long, tube-like organ in the abdomen that links the stomach to the rectum and absorbs food nutrients. It consists of the small and large intestines (also known as the small and large bowel).

Investigator Brochure

The document that includes all current knowledge about the medication being tested, including the medication’s safety data. The Investigator Brochure is part of the package of documents that must be reviewed and approved by the Ethics Committee before a new clinical trial begins.

Ionizing radiation

Ionizing radiation is made (or “given off”) by x-ray procedures, radioactive substances, rays that enter the Earth's atmosphere from outer space, as well as other sources. At high doses, ionizing radiation increases the chemical activity inside cells and can lead to health problems, such as cancer.


The colored portion of the eye containing a circular opening, the pupil, in its center.


A condition involving inflammation of the eye's iris. The iris is a part of the middle layer of the eye (uvea), so iritis is sometimes called anterior uveitis.