How Clinical Trials Really Work: Understanding the 4 Phases

NEW YORK, NY — November 13, 2026 — (NOTICIAS NEWSWIRE) — The idea of participating in a clinical trial can feel overwhelming, especially if you aren’t sure what’s actually involved in the process. Understanding how clinical trials work can help demystify the experience, while the research itself helps answer important questions about diseases, treatment options and more.

According to a study by the Crohn’s & Colitis Foundation, nearly 1 in 100 Americans has inflammatory bowel disease (IBD), a term encompassing a group of conditions that includes Crohn’s disease and ulcerative colitis. These disorders affect the gastrointestinal tract and cause inflammation of the intestines, which can lead to symptoms and sometimes more complicated issues throughout the body. Research into this condition has the potential to change lives, including those of the participants themselves, yet many clinical trials face delays due to lack of enrollment.

“We need more people to get involved in clinical trials, especially those from underrepresented communities, including people of color and older adults, who have some of the highest rates of chronic disease,” said Dr. Ruby Greywoode, a gastroenterologist at Montefiore Medical Center.

Clinical trials can take many forms including medication studies, medical tests, investigating the role of diet in disease management or examining the emotional impact of living with a condition such as IBD. Each trial is typically divided into four phases, which all build on each other but are conducted separately.

If you, your healthcare team and the study researchers decide an experimental drug trial is right for you, different questions will be answered depending on which phase you participate in.

Phase 1: Is the Drug Safe to Use?

The first phase of a clinical trial is the smallest and often conducted among a group of healthy people who don’t have the condition in question. Researchers want to know how the human body reacts to the medication, determine safe dosage ranges and identify potential side effects.

Phase 2: Is the Drug Effective?

Once a drug has been evaluated for overall safety in healthy people, the clinical trial moves on to test the treatment in a slightly larger group of people. Those participating in this phase have the condition for which the new treatment is being developed. For instance, a phase 2 IBD clinical trial might give the drug to 100 people with IBD to see whether it works or causes any short-term side effects. Participants are randomly assigned to different treatment groups, which may involve different dosages or placebos (not active treatment).

Phase 3: Does It Work Better Than Currently Available Treatments?

If the second phase yields positive results, the study expands again to test the new drug against current treatment options. A phase 3 clinical trial lasts longer and involves more participants than the first two phases as researchers try to gain as much information as possible about how the drug affects different kinds of people, whether it’s better than standard treatments or placebos and what side effects may arise over a longer period of time.

At the end of this phase, the company decides whether the trial results are strong enough to submit an application to the FDA, at which point the treatment will be reviewed and potentially approved.

Phase 4: How Does the Drug Work in Real Life?

Research usually doesn’t end when a drug gets approved. Instead, it moves into the fourth phase, where companies monitor the ongoing real-world uses and effects of the medication. This can involve following thousands of patients for several years to gather as much information as possible.

If you’re one of the millions of people living with IBD in the U.S., clinical trials offer hope for a future with more treatments, less pain and healthier lives. That’s why the Crohn’s & Colitis Foundation wants to make clinical trials less mysterious, more accessible and more representative of the real people affected by these conditions.

Talk to your healthcare professional about whether a clinical trial could be right for you and explore IBD research opportunities at CrohnsColitisFoundation.org.

Clinical Trial FAQs

What is the average length of a clinical trial?

The length of clinical trials vary. They can be as short as a month or as long as one year or more. Generally, the earlier the phase, the shorter the trial period.

How do you identify clinical trials you’re eligible for?

Eligibility criteria differ from study to study and may include factors like age, gender, medical history and current health status. For instance, some IBD studies may be looking for patients with mild symptoms, while others want to test treatments for moderate to severe disease. If you’re interested in a particular trial, review the criteria to see if you qualify to participate.

Is it free to participate in clinical trials?

Most clinical trials are federally or privately funded, so there is typically no cost to the participant. Associated costs like travel, time off work and childcare may or may not be covered by the trial sponsor, so it’s worth confirming these details before committing.

What if you enroll in a trial then change your mind?

You’re free to withdraw from a clinical trial at any time. If you drop out during testing, you may be asked to come in for follow-up visits to ensure your safety.

If the treatment helps, can you keep using it after the trial ends?

It depends. Some trial sponsors allow participants to continue receiving the drug voluntarily, while others only make it available after it’s been approved by the FDA.

How can you get involved in clinical trials?

Talk to your doctor about whether participating in a clinical trial may be right for you. If you’re interested in IBD clinical trials, you and your doctor can search for opportunities at crohnscolitisfoundation.org/clinical-trials-community.

“Clinical trials give patients a real way to shape the future of treatment,” Greywoode said. “It’s not just about their own care; it can help others, too. Talking openly with your doctor can help you feel more confident about getting involved.”

Photos courtesy of Shutterstock
Feature Impact
Source: Crohn’s & Colitis Foundation

CONTACT:
Sarah Fowler
913-647-0938
sarah.fowler@featureimpact.com