Clinical Trials 101

Clinical trials are research studies that test new medicines and strategies in people with conditions like Crohn’s disease and ulcerative colitis. This overview explains how trials move from early safety testing to large studies that support drug approval, and what participation usually involves. It also highlights protections for participants and practical questions to consider before someone with IBD joins a study.

Key Takeaways

• Clinical trials test whether new IBD treatments are safe, tolerable, and effective compared with current options or placebo. (fda.gov)

• Drug development usually moves from preclinical lab work into human studies in phases, from Phase 1 to Phase 4. (fda.gov)

• Each phase has a different main goal: early safety, signs of benefit, comparison with standard care, and long‑term monitoring. (cancer.gov)

• Participation is voluntary and requires informed consent, screening, regular visits, and close safety monitoring. (toolkit.ncats.nih.gov)

• Independent review boards and safety committees help protect participants’ rights, privacy, and well‑being. (toolkit.ncats.nih.gov)

What clinical trials are

Clinical trials are planned research studies that involve human volunteers. They test new medications, combinations of existing drugs, procedures, or care strategies. (en.wikipedia.org)

Trials follow a written plan called a protocol. The protocol lays out who can join, what treatment is given, and what outcomes are measured. Outcomes may include symptom scores, stool frequency, endoscopic healing, or quality of life.

Clinical trials are different from regular clinical care. In routine care, a clinician chooses treatments mainly for one person’s needs. In a trial, treatments follow the protocol so that researchers can answer a clear scientific question.

From lab to people: preclinical work and early phases

Before any new IBD drug reaches people, it goes through preclinical testing. Preclinical studies involve lab experiments and animal models to explore how a drug works and to estimate safe starting doses. (en.wikipedia.org)

Only treatments that look reasonably safe and promising move into human studies. Regulators such as the U.S. Food and Drug Administration (FDA) review preclinical data in an Investigational New Drug application before trials can begin. (fda.gov)

Some trial listings mention “Early Phase 1” or “Phase 0.” These very early human studies use tiny doses to gather extra information on how a drug behaves in the body. Most IBD patients first see studies at Phase 1 or later. (registries.ncats.nih.gov)

Clinical trial phases at a glance

Regulators usually describe four main phases of drug trials. Each phase builds on the previous one and involves more people. (fda.gov)

*Numbers are typical ranges, not strict rules. (cancer.gov)

Results from Phase 1 to 3 trials are used to decide whether a medicine should be approved for public use. Phase 4 studies happen after approval and continue to monitor safety and effectiveness over time. (fda.gov)

Who can join an IBD clinical trial?

Each trial has inclusion and exclusion criteria. These rules aim to protect participants and to make the results clear.

Common inclusion criteria in IBD trials may include:

• A confirmed diagnosis of Crohn’s disease or ulcerative colitis

• A certain level of disease activity, such as moderate to severe symptoms

• Previous exposure or lack of exposure to specific medications

• Age limits, such as adults only, or children and teens only

Common exclusion criteria may include:

• Uncontrolled infections or serious heart, liver, or kidney problems

• Pregnancy or breastfeeding

• Recent major surgery

• Use of conflicting medications that could affect safety or results

A study team reviews medical records, performs an exam, and sometimes orders blood tests, stool tests, or endoscopy to see whether someone qualifies.

What participation usually involves

Participation starts with an informed consent process. The research team explains the trial’s purpose, treatments, possible benefits, and known or unknown risks in plain language. A person can ask questions and does not sign until they feel comfortable with the information. Consent can be withdrawn at any time.

Common steps in an IBD trial include:

• Screening visit to review history, do labs, and confirm eligibility

• Randomization, often by computer, to assign the study medicine or a comparison group

• Study treatment, given as pills, injections, infusions, or rectal therapies

• Regular follow‑up visits for symptom checks, blood work, sometimes imaging or endoscopy

• Symptom diaries or digital tracking, for example stool counts or pain scores

Some trials use a placebo, which looks like the study drug but contains no active medicine. Placebo is often given on top of stable background therapy, not alone, especially when effective standard treatments exist.

Potential benefits and downsides

Possible benefits of joining an IBD trial include:

• Access to a new treatment before it is widely available

• Very close monitoring and frequent contact with a research team

• Extra tests that may give a clearer picture of disease activity

• Contributing to better options for future patients

Possible downsides include:

• Unknown or unexpected side effects

• More time spent at the clinic, including travel and missed work or school

• Discomfort from extra blood draws, scans, or procedures

• The chance of receiving placebo or a dose that does not work well

Trials usually cover the cost of the study drug and research‑related tests. Regular care costs, such as standard lab work or clinic visits, may still be billed to insurance. Policies vary by trial and site, so the research team needs to explain this clearly.

Safety protections and oversight

Ethics and safety are central to clinical research. Every trial is reviewed by an Institutional Review Board (IRB) or ethics committee. The IRB checks that risks are reasonable and that participant rights and privacy are protected. (toolkit.ncats.nih.gov)

Many larger trials also have an independent Data Safety Monitoring Board (DSMB). This group of experts reviews unblinded safety data at intervals and can recommend changes or early stopping if concerns arise. (toolkit.ncats.nih.gov)

Study teams follow Good Clinical Practice standards. Participants are given contact information for urgent questions or side effects. The person’s regular gastroenterologist often stays involved, coordinating with the trial team about flares or other health issues.

Participation is always voluntary. A person can leave a trial at any time, for any reason, and should still receive appropriate medical care.

Practical questions to ask about an IBD trial

Before joining, many patients and families find it helpful to ask:

• What standard treatment options are available outside this trial?

• What is the main goal of this study in IBD?

• What treatments might be given, including placebo or comparison drugs?

• How many visits, tests, scopes, or infusions are expected, and over what time frame?

• Which costs are covered by the study, and which go through insurance?

• What happens if symptoms worsen during the trial?

• Can current medications be continued, and which ones must be stopped?

How people find IBD clinical trials

People interested in research often learn about trials through their gastroenterologist, IBD nurse, or major IBD centers. Public registries such as ClinicalTrials.gov and patient‑focused organizations also list open studies and sometimes offer matching tools. (registries.ncats.nih.gov)

Searching by condition (Crohn’s disease or ulcerative colitis), location, and age group can help narrow the list. A clinician can then review specific trials to see whether any fit a person’s medical situation and preferences.