The U.S. Food and Drug Administration (FDA) has expanded the indication of Eli Lilly and Company’s Taltz (ixekizumab) to include active ankylosing spondylitis (AS). The humanized interleukin-17A antagonist initially received approval in 2016 for the treatment of plaque psoriasis, and in 2017 of active psoriatic arthritis (PsA). It now competes with Novartis’ Cosentyx (secukinumab), which is indicated to treat the same three rheumatic diseases. Cosentyx garnered FDA approval in 2015 for the treatment of plaque psoriasis, and picked up the subsequent approvals for AS and PsA in 2016.
Efficacy/Outcomes
The latest indication for Taltz follows two randomized, double-blind, placebo-controlled phase 3 studies including 657 adults with active AS. COAST-V evaluated patients without a history of biologic disease-modifying antirheumatic drugs (bDMARDs), while COAST-W analyzed patients with a previous inadequate response or intolerance to tumor necrosis factor (TNF) inhibitors. Each study had the same primary efficacy endpoint: the proportion of patients achieving 16-week Assessment of Spondyloarthritis International Society 40 (ASAS40) response compared to placebo. In COAST-V, among patients receiving Taltz 80 mg every four weeks, 48% of Taltz patients achieved 16-week ASAS40, versus 18% of placebo patients, and in COAST-W, it was achieved by 25% and 13% of patients, respectively. The secondary endpoint was the proportion of patients who achieved ASAS20 after 16 weeks. In COAST-V, 64% of Taltz patients and 40% of placebo patients met this endpoint, and in COAST-W, 48% and 30% did, respectively.
Cosentyx was tested in AS patients in two randomized trials: MEASURE 1 and MEASURE 2. In these studies, the primary endpoint was the proportion of patients who achieved ASAS20 after 16 weeks. Among patients receiving 75 mg Cosentyx in MEASURE 1, 60% of patients achieved ASAS20, compared to 29% of placebo patients; in MEASURE 2, the outcomes were 41% and 28%, respectively.
Safety
In Taltz, the most common adverse reactions are injection site reactions, upper respiratory tract infections, nausea, and tinea infections. In Cosentyx, they are nasopharyngitis, diarrhea, and upper respiratory tract infection.
Cost
According to Drugs.com, the cost of Taltz subcutaneous solution (80 mg/mL—the suggested dose) is an estimated $5,613/supply. The cost of Cosentyx subcutaneous solution (150 mg/mL—the suggested dose) comes to about $5,415/supply.