Clinical Trial Tests Stelara for Psoriatic Arthritis Relief
Two recent Phase III clinical trials, sponsored by Janssen Biotech, Inc. demonstrated that the drug Stelara (ustekinumab) is able to partially block joint damage and relieve symptoms caused by psoriatic arthritis for up to two years.
What is Psoriasis and Psoriatic Arthritis?
As the name indicates, psoriatic arthritis, there is a link to psoriasis. About 15% of people who have psoriasis, a disease that causes the immune system to attack the skin, will develop psoriatic arthritis. The condition can be very serious, leading to permanent damage of joints such as knees and knuckles.
At best, psoriasis and psoriatic arthritis are debilitating and painful (like the rheumatoid arthritis, which is treated with methotrexate for RA). For mild cases, treatment has often consisted of taking NSAIDS (ibuprofen, naproxen), but the trend is to use antirheumatic drugs at an earlier stage. Psoriasis, like many immunological diseases, is the result of the body’s immune system attacking its own organs and tissues. In this case, the body ‘recognizes’ some foreign biological presence in the skin and proceeds to deal with it by martialing many of the immune responses such as inflammation, blood vessel dilation and tissue displacement. The results are the rashes, itches, skin eruptions, discoloration, and disfigurement of psoriasis.
Stelara Clinical Trial for Use to Treat Psoriatic Arthritis
Stelara was approved by the U.S. Food and Drug Administration in 1999 as a treatment for psoriasis. It’s an immunosuppressant (technically, a monoclonal antibody) – it lowers the immune response for the entire immune system.
Although originally designed for psoriasis, the manufacturer believed it also had a chance of treating psoriatic arthritis, which was the basis for the sequence of clinical trials (Phases I through III).
For the final Phase III trial researchers designed a multicenter, randomized, double-blind, placebo controlled study involving 927 patients, all of them suffering from diagnosed psoriatic arthritis.
The trials used two dose levels of Stelara, 45mg and 90mg injected under the skin, depending on the stage of the patient’s disease. The goal (hypothesis) of the trial was that Stelara would prevent or inhibit joint damage caused by the arthritis. In the trial, one group of patients was also treated with methotrexate (in low doses, a common drug for arthritis).
The results, whether for Stelara alone or in combination with methotrexate, was effective in at least partially stalling the deterioration of joint tissue and bone; 42% of the patients had a 20% improvement in symptoms – not a cure, but a long-term means of blocking progression of the disease.
People in the placebo group (receiving no treatment with Stelara) had no improvement in their condition and after four months, began taking Stelara.
Stelara Clinical Trial Results
Stelara is functionally an anti-inflammatory drug. It inhibits several of the immune system proteins (cytokines) from triggering the body’s inflammation response. Like several other drugs of its type, such as azathioprine (Imuran), cyclosporine (Neoral) and leflunomide (Arava), the suppression of the immune system/inflammation response is general (i.e. not specific to psoriasis), which means that side effects can also be general.
As should be expected, lowering the effectiveness of the immune system leaves the body more vulnerable to other diseases and complications. In fact, Stelara like other drugs of its ilk, have an impressive side effects list: risk of serious infection, certain cancers, serious allergic reactions, and a brain condition (potentially fatal reversible posterior leukoencephalopathy syndrome).
These are not common, but altering the immune system is, for lack of a better phrase, something of a crapshoot. One of the principal results of the Phase III trial was the indication that as a psoriatic arthritis drug, Stelara was tolerable for most of the participants and produced an “acceptably low level of side effects.” These conditions were good enough for the U.S. FDA to approve the drug for arthritis in September of 2013.