Clinical Trials for Psoriatic Arthritis

Medically Reviewed by Melinda Ratini, MS, DO on July 27, 2022
4 min read

Psoriasis is a common skin condition that affects 125 million people worldwide, and about 30% of those living with psoriasis will also develop psoriatic arthritis.

Medication has proven effective for controlling the symptoms of psoriatic arthritis (PsA), which include joint tenderness and swelling, fatigue, morning stiffness, and reduced range of motion, but it can take time to find the right treatment (or combination of treatments) and some come with short-and long-term side effects.

Researchers are always looking for new PsA treatments, and clinical trials can help.

Clinical trials are research studies that evaluate the effectiveness of new treatments, find the right medication dosages, look for side effects, and decide whether the treatments being tested are safe and effective.

Researchers must present their clinical trial proposal to the FDA to get approval to do the studies. The FDA also uses the results from clinical trials to determine whether new PsA treatments are safe and effective enough to be approved for patient use.

Clinical trials are separated into four phases:

  • Phase I: These studies recruit small groups of participants to test whether new treatments are safe and effective. When the researchers see that the treatment is helping, it moves on to the next stage of testing.
  • Phase II: A phase II clinical trial can include several hundred participants and is designed to further test whether a treatment is safe and effective. Compared to phase I clinical trials, which last a few months, phase II clinical trials can last up to 2 years.
  • Phase III: Once a treatment has progressed to a phase III clinical trial, researchers recruit thousands of participants and monitor for side effects over longer periods of time. The FDA uses the results from phase III trials to approve treatments that show positive results.
  • Phase IV: These studies happen after new treatments have been approved and include larger and more diverse populations than those included in phase I, II, and II clinical trials and monitor patients over longer periods.

From a research perspective, clinical trials allow scientists to learn more about how new psoriatic arthritis treatments can help patients.

Clinical trials also help patients. You get access to new PsA treatments and access to health care providers on the cutting edge of psoriatic arthritis research, plus the benefit of knowing that you’re helping researchers on their quest to find a cure for psoriatic arthritis and helping others who live with the disease.

There have been significant increases in the number of options for treating psoriatic arthritis. In fact, the FDA approved three new drugs to treat psoriatic arthritis between 2013 and 2017 after clinical trials showed positive results for all three therapies.

Sometimes, clinical trials help researchers better understand when certain treatments are ineffective. In 2021, researchers completed a clinical trial that explored whether cannabidiol (CBD oil) could help control the symptoms of psoriatic arthritis; the resulting study found no significant differences in reported pain among those who took CBD.

The number of treatments for PsA have increased, but researchers believe there is an ongoing need to continue testing potential new therapies with clinical trials to improve care.

Researchers are always launching new clinical trials to test new treatment options for psoriatic arthritis. They also study other aspects of PsA, from prevention and diagnosis to disease activity and lifestyle changes. Some of the clinical trials currently in progress include:

  • Testing the effectiveness of a dietary probiotic for lowering disease activity.
  • Comparing X-rays to assess long-term joint damage and assess factors that might predict those with PsA who are at highest risk for severe disease.
  • Assessing the impact of diet on PsA symptoms and disease severity.
  • Determining factors that affect willingness to stick with a medication regimen.

New clinical trials are recruiting participants all the time.

While clinical trials for PsA test a range of treatments or prevention strategies, all will follow similar steps: You’ll be randomly assigned to a treatment or control group, given a list of instructions to follow, and asked to schedule follow up appointments during the trial that could include collecting urine samples, having blood draws, and other health screenings so researchers can collect data.

Some clinical trials provide reimbursement for costs like travel, parking, and lodging or offer a small stipend to participants.

Researchers may decide to end a clinical trial early if there is clear proof that the treatment is effective, if there is lack of interest, if participants experience severe side effects, if the harms are greater than the benefits, or if other similar research is published that makes the clinical trial irrelevant.

It’s important to talk to your doctor before enrolling in a clinical trial. If you decide to apply, here are some questions to ask the clinical trial coordinator:

  • What is the purpose of the clinical trial?
  • What are the possible benefits, side effects, and risks of the clinical trial?
  • If the treatment works, can I continue with it after the trial ends?
  • What happens to the data collected in the trial?
  • Will I be informed of the results of the trial?
  • Will my health care provider have access to the medical records from the clinical trial?

The more information you have about the goals of a clinical trial and how it might help you (and others) live better with psoriatic arthritis, the better able you’ll be to make a decision about whether to participate.