Psoriatic arthritis, an inflammatory autoimmune arthritis disease, which if left untreated or treated unsuccessfully, can initiate severe joint, bone damage and functional disability. Affecting nearly 2 percent of the population, this arthritis commonly develops between the ages of 30 to 50 with symptoms like pain, swelling and stiffness.

Most commonly used biologics for rheumatoid and psoriatic arthritis are Adalimumab, Etanercept and Infliximab which blocks the action of pro-inflammatory elements (TNF). However, only half of the psoriatic arthritis patients get relief from these medications.  

From last decade, IL-17 (another pro-inflammatory substance) has been in the limelight by the immunologists for psoriasis and psoriatic arthritis. Ixekizumab, an injectable monoclonal antibody, is already commercially available effective treatment of psoriasis which blocks IL-17. This drug has been proved to be useful for psoriatic arthritis patients who had not yet been treated with biological drugs like the TNF inhibitors.

The efficacy of Ixekizumab was explored in a 24-week randomized, double-blind, placebo-controlled, pivotal phase-3 clinical trial (SPIRIT-P2) conducted by Stanford University School of Medicine investigator. The trial was conducted at 109 centers in 10 countries which involved a total of 314 patients. These patients were those who did not have relief from their standard-of-care pharmaceutical treatments. The patients were divided into two groups- one group comprising of target drug (Ixekizumab) and another of placebo. All in all, 109 patients received Ixekizumab, and 94 received placebo every two weeks. The remaining 111 patients were substituted between Ixekizumab and the placebo for every two weeks. The trial results were presented online in The Lancet.

There was a 20% reduction in joints tenderness and swelling in the Ixekizumab group. As for placebo, only 19.5% patients met the trial's specified clinical endpoint. There was a response rate of 53.3 percent in those getting real drug every four weeks. As for those getting the drug every two weeks didn't do any better being more prone to side effects like a mild reaction at the injection site.

As any treatment works by preventing the ability of immune system to tackle an inflammation response, it should be carefully observed to check whether it may enhance the body's vulnerability to infectious ailments.