A clinical trial is a research study that determines whether specific healthcare interventions—such as investigational therapies, medicines and treatments—are safe and effective. Clinical trials are essential for making medical progress and helping Johnson & Johnson address the world’s most complex diseases.
Before reaching the clinical trial stage, investigational interventions may undergo various types of preclinical research and testing. The clinical trial process itself can include:
- Phase 1: Researchers test the investigational drug or treatment in a small group of people to learn about its safety, including how it is absorbed by the body, what dosage should be used and potential side effects.
- Phase 2: The intervention is given to a larger group of people to better understand ongoing safety, whether it works for a particular disease and the best dose.
- Phase 3: The intervention is given to an even larger group of people. The main objectives are studying safety and side effects in bigger populations, whether it works for a particular disease and often how it compares to already existing standard therapies.
In some cases, there may be a fourth phase after the intervention is approved in which researchers study long-term risks, benefits and side effects during day-to-day use in the population.
While these phases are standard protocol for clinical trials, the actual length of the study depends on the intervention itself, what the trial is evaluating and the end goal.
Representative research in clinical trials
Advancing representative research in clinical trials is good science. It is part of Johnson & Johnson’s ongoing commitment to putting patients first and ensuring that medical discoveries are accessible to patients who need them.
Recruiting participants from various backgrounds helps us understand how medicines affect people around the world who are impacted by certain conditions and diseases. That’s why Johnson & Johnson works with patient advocates, nurses, community health workers and organizations to give people comprehensive information and resources to dispel common misperceptions and drive greater understanding of clinical trials.
Commonly asked questions about clinical trials
1. What can I expect in a clinical trial?
Clinical trials vary in length and purpose, but the core process is the same:
- Screening: Before you join a trial, the trial doctor and staff will determine if you meet the specific requirements to participate. You will also receive an Informed Consent Form (ICF) to ensure you’re fully aware of the potential risks and benefits of the trial.
- Enrollment: Once you’ve completed screening and it is determined that you qualify, you will have the opportunity to enroll in the trial and become an active participant.
- Investigational Treatment Phase: In this part of the trial, you will receive your assigned trial medication and begin to have regular study visits. The number of visits and length of time you remain in the trial will depend on the specific trial. During this phase, you will be monitored with clinic visits, tests and assessments.
- Follow-Up: During the Follow-Up period, you will no longer take the investigational medication, but you may continue to attend clinic visits. The trial doctor and staff will stay in touch with you to continue monitoring your health and the effects of the treatment. The length of time you spend in the Follow-Up period varies based on the trial.
2. Are clinical trials safe?
Johnson & Johnson is committed to putting patients first. Your safety and well-being are our top priorities in every clinical trial. We’re always working to make our research trials even safer, more effective and easier for you to participate in.
3. How will my privacy and personal information be protected?
In a clinical trial, your identity and any medical information collected is confidential. It is only available to the people and organizations involved in the trial. For example, before any lab tests can be done on samples taken from your body (like blood or urine), you must be told about it and asked for your permission. Even if you give permission, you can change your mind at any time, for any reason. The samples and data that are obtained are protected and can only be used for research purposes. There are laws in place to prevent information from being shared for other purposes.
4. Why should I consider participating in a clinical trial?
By participating, you will be helping researchers learn more about your condition, which could lead to breakthroughs for others facing the same challenges.
5. How can I find a clinical trial that is right for me?
If you are interested in learning more about participating in a clinical trial, visit our Global Trial Finder to search for trials by condition and location. Your doctor, nurse or other trusted healthcare professional can also help you search for trials that are available and determine if participating is appropriate for you.
This story was originally published on May 15, 2023 and updated on May 13, 2025.
