Possible new drug option for psoriatic arthritis


Ustekinumab, a drug used to treat psoriasis, has now shown promising results for people with psoriatic arthritis, including people for whom other treatments haven’t helped.


Psoriatic arthritis is a long-term condition that causes pain and swelling in some joints, including the spine, and in the soft tissues around the joints, such as the tendons. As well as pain it can cause fatigue (being exhausted), reduce people’s mobility, and affect their quality of life. There are drugs that can relieve the inflammation and symptoms of psoriatic arthritis. These include some you may have heard of, such as methotrexate, and newer drugs called TNF-inhibitors (also called anti-TNF drugs). But there is no one drug that works for everyone. And some people find that side effects stop them using some medicines.

Ustekinumab is a fairly new medicine of a type called a monoclonal antibody. Thus, like TNF-inhibitors, it is a biological disease-modifying anti-rheumatic drug. It has been used for some years to treat psoriasis. And it is now approved to treat people with psoriatic arthritis in US as well as in many countries in Europe. The new study looked at 312 adults with psoriatic arthritis whose symptoms had not improved much with other treatment, or who had stopped using other drugs because of side effects. More than half of the people in
the study had already tried TNF-inhibitors.

The people in the study took either ustekinumab or a dummy treatment (placebo) for six months. During the study they were allowed to keep taking any other medicines that helped them.


More people who took ustekinumab had improvements in their symptoms compared with people taking placebo. The main way the study measured symptom improvement was by using a tool called the ACR20. ACR is short for American College of Rheumatology and the ‘20’ refers to a 20 percent improvement in tender and swollen joints and in other findings/symptoms. After six months about 44 in 100 people taking ustekinumab achieved ACR20 (their symptoms improved by at least 20 percent) compared with about 20 in 100 people taking a placebo.

The new drug also seemed to help people for whom TNF-inhibitors hadn’t worked. About 36 in 100 of these people who took ustekinumab achieved ACR20 compared with about 15 in 100 people who took a placebo. More people taking ustekinumab had improvements in other symptoms including fatigue, psoriasis, physical function (moving their joints), and in quality of life, compared with people taking placebo. Finally, ustekinumab
didn’t seem to cause any unexpected or alarming side effects.


This was a type of study called a randomised controlled trial, which is the best type of research for directly comparing treatments. It was a well-conducted study with careful methods, so it should be fairly reliable.


For now, ustekinumab is available in many countries for treatment of both psoriasis and psoriatic arthritis. For some people, finding a helpful treatment for psoriatic arthritis involves a difficult journey through several options. This study suggests that ustekinumab could become one of those options, but it is expected that clinicians
will use methotrexate followed by TNF-inhibitors as the first options (also because TNF-inhibitors usually are cheaper and seem to have similar efficacy on a group level). Thus, ustekinumab will be an important rescue option for people not responding to TNF-inhibitors, in particular because ustekinumab has a different
mode of action by inhibiting other inflammatory mediators than TNF.

Disclaimer: This is a summary of a scientific article written by a medical professional (“the Original Article”). The Summary is written to assist non medically trained readers to understand general points of the Original Article.  It should not be relied on in any way whatsoever, (which also means the Summary is not medical advice), and is simply supplied to aid a lay understanding of general points of the Original Article. It is supplied “as is” without any warranty. You should note that the Original Article (and Summary) may not be accurate as errors can occur and also may be out of date as medical science is constantly changing.  It is very important that readers not rely on the content in the Summary and consult their medical professionals for all aspects of their health care. Do not use this Summary as medical advice even if the Summary is supplied to the reader by a medical professional.
Please view our full Website Terms and Conditions.

Date summary prepared: June 2014

Summary based on research article published on: 30 January 2014

From: Ritchlin, C. et al. Efficacy and safety of the anti-IL-12/23 p40 monoclonal antibody, ustekinumab, in patients with active psoriatic arthritis despite conventional non-biological and biological anti-tumour necrosis factor therapy: 6-month and 1-year results of the phase 3, multicentre, double-blind, placebo-controlled, randomised PSUMMIT 2 trial. Ann Rheum Dis 2014;73:990-999 doi:10.1136/annrheumdis-2013-204655

Copyright © 2015 BMJ Publishing Group Ltd & European League Against Rheumatism. Medical professionals may print copies for their and their patients and students non commercial use. Other individuals may print a single copy for their personal, non commercial use. For other uses please contact our Rights and Licensing Team.