Reason for Discontinuing First Therapy Relates to Response to Second Therapy in Severe Psoriasis or Psoriatic Arthritis Patients

The reason for discontinuing tumor necrosis factor (TNF)—alpha inhibitor therapy in severe psoriasis or psoriatic arthritis patients may correlate to how well they respond to treatment with a different TNF-alpha inhibitor.

How well patients with moderate or severe psoriasis or psoriatic arthritis respond to another tumor necrosis factor (TNF)—alpha inhibitor may relate to the reason for discontinuing their initial treatment course, the results of a study suggest.

According to the study, published in the February 2014 edition of Journal of the American Academy of Dermatology, reasons for switching to a different TNF-alpha inhibitor included primary inefficacy; loss of initial response; and adverse events, drug intolerance, and “other,” which could include a physician’s decision.

In general, participants who switched because of secondary loss of efficacy, adverse events, drug intolerance, or physician’s decision were more likely to see clinically significant improvement than participants who switched therapy because of failure to respond to their initial therapy course.

The participants included 105 adults with a confirmed diagnosis of either chronic plaque psoriasis or psoriatic arthritis. The treatment agents included adalimumab, infliximab, or etanercept.

“The differences in response to several TNF-alpha inhibitors can be linked to the differences in their bioavailability and stability and in patients’ genetics,” the researchers wrote. “These drugs also differ in terms of their immunogenicity or potential to induce antidrug antibodies, which may be associated to a secondary loss of response over time.”

After 16 weeks on the second TNF-alpha inhibitor, 29% of participants achieved clinically significant improvement. By 24 weeks, 45.6% of participants saw clinically significant condition improvement. After a year of therapy on the second TNF-alpha inhibitor, 74.1% of participants saw clinically significant condition improvement.

According to demographic data researchers gathered at the study outset, etanercept was the most frequently prescribed baseline therapy, with 60% of participants receiving it. Infliximab therapy was the next-most frequently prescribed therapy, with 35.2% of participants receiving it, whereas only 4.8% of participants received adalimumab as initial therapy.

Adalimumab tended to be prescribed more frequently as the second TNF-alpha inhibitor than as initial therapy, with 41% of participants being switched to it. Researchers attributed the switches to adalimumab being introduced into clinical practice at a later date than the other therapies.

Meanwhile, 37.1% of participants were switched from their initial therapy to infliximab, and 21.9% from their initial therapy to etanercept.

Most participants—60%—switched from etanercept to monoclonal antibodies, whereas 20.9% switched from monoclonal antibodies to etanercept. Meanwhile, 18.1% switched from 1 monoclonal antibody to another monoclonal antibody.

Participants who switched their therapy had been treated with the first TNF-alpha inhibitor for an average of 58.4 weeks, researchers noted.

“This prospective, open, registry-based study shows that switching to a second TNF-alpha inhibitor can be effective in some psoriatic patients, particularly in cases of a secondary loss of response to a previous TNF-alpha inhibitor or to drug intolerance,” the researchers wrote.