Clinical Trials 101

What starts with research leads to tomorrow's psoriasis and psoriatic arthritis treatments.

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In the U.S., medical treatments undergo rigorous testing and are regulated by the U.S. Food and Drug Administration (FDA) prior to being made available for use by patients.

Part of this testing includes clinical trials, the primary way that researchers examine and ultimately determine the safety and efficacy of medical treatments. The findings from clinical trials are submitted to the FDA to review and determine if a new treatment will be approved to go to market.

By participating in a clinical trial, you are helping the research community move closer to finding a cure for psoriatic disease and improving the lives of those affected.

Clinical trials involve 4 phases of testing on human participants for safety and efficacy.

Phase 1

Phase 1 studies involve a smaller group of participants (20 to 100 participants) to examine the safety (and dosage, if applicable) of the new treatment. Generally this phase can last several months. If the treatment produces positive results during phase 1 study, it can move to Phase 2. 

Phase 2

Phase 2 studies can involve up to several hundred participants to examine efficacy and side effects of a treatment over the course of several months to 2 years. If there are favorable results from the phase 2 study, a treatment or device continues to Phase 3.

Phase 3

Phase 3 studies examine efficacy and monitoring of adverse reactions among 300 to 3,000 participants, studying effects in different populations and at different dosing amounts. This study can last between 1 and 4 years. At the end of the study period, the FDA will move to approve a treatment if the outcome of Phase 3 study is positive.

Phase 4

Phase 4 studies occur after a treatment has been approved and generally monitors a treatment's safety and efficacy in a larger, more diverse population for a longer period of time. These studies can also focus on special populations or studying specific questions like how the medication may interact with other medications

Making an Educated Decision

People join clinical trials for many reasons. Some people may be looking to take on a more active role in their healthcare, while others may be more interested in helping future generations. No matter the reason, it is important that you make an educated decision.

You and your health care provider should discuss if clinical trials are right for you. When making any type of treatment decision, you might consider your disease severity, your reactions to previous treatments, and other health conditions you might be coping with.

Keep in mind that you may withdraw from a study at any time for any reason.

Informed Consent

Prior to the start of a clinical trial, you will be provided with an informed consent that you will need to read and sign.

Clinical Trials 101

The informed consent provides you with information related specifically to the trial you are participating in so you will have a clear understanding of the study, your role, and the expectations of you before you begin. 

Giving written consent to participate in a clinical trial means that you acknowledge, understand, and accept all aspects of the study. This includes any possible benefits or risks. The physicians and research staff are responsible for helping you understand the information. They should give you enough time to make a decision about participating in the clinical trial. You can always ask questions if you do not understand something about the study or if you have other concerns.

You have the right to the following:

  • Know the purpose of the clinical trial and what will happen during the study
  • Be informed of all of the possible benefits, side effects, and risks that might be reasonably expected and any medical treatments available if complications occur during the study
  • Right to ask questions about the clinical trial before giving consent and at any time during the study
  • Sufficient time to make your decision about participating without pressure to make a decision
  • A signed and dated copy of the informed consent form
  • Right to refuse to participate for any reason before the trial has started and at any time during the study

After a Clinical Trial Ends: The Participant Perspective

You may have some questions or concerns about what will happen to the treatment and your treatment plan after a study has ended. It is important that you speak with the research staff about your concerns.

Some possible questions you can ask:

  • If the treatment is helping, is it possible to stay on it?
  • If you cannot stay on that treatment, what are your next steps for getting onto a new treatment plan?
  • What happens to your data and information?
  • Will you receive results from this study? If so, when and how?
  • Can you or your health care provider access your medical records from the study?

If you are unable to access health care outside of a clinical trial, speak with the research staff about your treatment options after the trial. It may be possible to join another clinical trial.

After a Clinical Trial Ends: The Treatment

The data collected during a clinical trial are analyzed to determine how safe and effective the treatment is. All data are de-identified so that no one will know an individual’s specific information. Researchers will use these findings to determine whether to stop testing or move to the next phase of clinical trials. Results from a clinical trial are often published in scientific journals and on

If the clinical trial was a Phase 3 study, researchers will analyze the data prior to submitting it to the FDA. If the data shows the treatment to be safe and effective, researchers will submit their findings to the FDA for approval. The FDA will review all of the data and findings from the clinical trial and make a decision on whether or not to approve the treatment and make it available on the market.

Treatments that become approved may continue to have clinical studies done in order to:

  • Compare the safety, effectiveness, and cost of the new treatment with other treatments that are currently available
  • Better understand the long-term safety and efficacy of the new treatment
  • Measure its impact on quality of life for people using the new treatment
  • Evaluate the treatment in other types of patients
  • Further characterize the treatment

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