The FDA has approved ixekizumab injection 80 mg/mL (Taltz, Eli Lilly and Company) for the treatment of adults with active psoriatic arthritis (PsA). Ixekizumab was first approved by the FDA in March 2016 for the treatment of adults with moderate-to-severe plaque psoriasis who are candidates for systemic therapy or phototherapy.
PsA is a chronic, progressive, and painful form of inflammatory arthritis that impacts approximately 1.6 million Americans.
Ixekizumab may be administered alone or in combination with a conventional disease-modifying antirheumatic drug, such as methotrexate. It should not be used in patients with a previous serious hypersensitivity reaction, such as anaphylaxis, to ixekizumab or to any of the excipients. Ixekizumab may increase the risk of infection. Other warnings and precautions for ixekizumab include pre-treatment evaluation for tuberculosis, hypersensitivity reactions, inflammatory bowel disease, and immunizations.
The efficacy and safety of ixekizumab were determined in two randomized, double-blind, placebo-controlled phase 3 studies—SPIRIT-P1 and SPIRIT-P2—which included more than 670 adult patients with active PsA. SPIRIT-P1 evaluated the safety and efficacy of ixekizumab compared to placebo in patients with active PsA who had never been treated with a biologic disease-modifying antirheumatic drug. SPIRIT-P2 evaluated the safety and efficacy of ixekizumab compared to placebo in tumor necrosis factor inhibitor (TNFi)-experienced patients with active PsA who failed one or two TNF inhibitors.
Across both studies, patients were required to have a diagnosis of active PsA for at least six months and at least three tender and three swollen joints. Nonresponder imputation (NRI) methods were used. Inadequate responders (defined by blinded tender and swollen joint count criteria) at week 16 received rescue therapy and were analyzed as nonresponders.
In studies of biologic-naïve and TNFi-experienced patients, the primary efficacy endpoint was the proportion of patients at 24 weeks achieving ACR20 response, which represents a 20% reduction in a composite measure of disease activity as defined by the American College of Rheumatology (ACR). Results from both studies demonstrated that patients treated with ixekizumab achieved significant improvement in joint symptoms, as measured by ACR20, compared with placebo. At 24 weeks, patients treated with ixekizumab achieved ACR20 at the following response rates versus patients receiving placebo: SPIRIT-P1, 58% versus 30%; and SPIRIT-P2, 53% versus 20%.
"For patients with PsA, treatment goals often include improvement in joint symptoms," said Philip Mease, MD, Swedish Medical Center and University of Washington. "Based on the study results, Taltz can provide significant improvement in joint symptoms for patients who had never been treated with a biologic disease-modifying antirheumatic drug as well as patients who had inadequate response to one or two TNF inhibitors or were intolerant of TNF inhibitors."
Source: Eli Lilly; December 1, 2017.