Ixekizumab demonstrates significant efficacy at week 16 with sustained efficacy for up to 52 weeks for biologic disease-modifying antirheumatic drug (bDMARD)-naive and tumor necrosis factor inhibitor (TNFi)-experienced patients with active radiographic axial spondyloarthritis (r-axSpA), according to study results published in the Annals of the Rheumatic Diseases.
The study combined the results of 2 phase 3 studies of the efficacy and safety of ixekizumab for patients with r-axSpA who were bDMARD-naive (COAST-V; ClinicalTrials.gov Identifier: NCT02696785) or TNFi-experienced (COAST-W; ClinicalTrials.gov Identifier: NCT02696798). In COAST-V, 341 patients were randomly assigned 1:1:1:1 to 80 mg ixekizumab every 2 weeks (Q2W) or 4 weeks (Q4W), placebo, or 40 mg adalimumab Q2W. In COAST-W, 316 patients were randomly assigned 1:1:1 to ixekizumab, Q2W, Q4W, or placebo. At week 16, patients who received ixekizumab continued their assigned treatment, and those who received placebo or adalimumab were randomly assigned 1:1 to ixekizumab Q2W or Q4W (placebo/ixekizumab, adalimumab/ixekizumab) through week 52.
A majority of patients in each trial completed the study through week 52 (COAST-V, 309/329; 93.9% and COAST-W, 250/281; 89.0%). Of those initially assigned to ixekizumab, 146/164 (89.0%) patients in COAST-V and 169/212 (79.7%) in COAST-W completed the study through week 52. The most common reasons for discontinuation were patient withdrawal in COAST-V (n=11; 3.3%) and lack of efficacy in COAST-W (n=11; 3.9%). Between-group demographics and baseline characteristics were similar in both studies.
Among the continuously treated ixekizumab patients, the week 16 Assessment in Spondyloarthritis International Society 40% (ASAS40) response rates were sustained for up to 52 weeks and were 53.1% (ixekizumab Q4W) and 50.6% (ixekizumab Q2W) in COAST-V and 34.2% (ixekizumab Q4W) and 30.6% (ixekizumab Q2W) in COAST-W. Among patients who received placebo assigned to ixekizumab at week 16 (placebo/ixekizumab), rapid improvement in ASAS40 response rates were observed after switching to ixekizumab, with the week 52 response rates similar to those for patients initially assigned to ixekizumab (46.5% in COAST-V, and 38.7% in COAST-W). In both studies, patients on continuous ixekizumab regimens sustained improvements up to 52 weeks in physical function, disease activity, objective markers of inflammation, health status, quality of life, and overall function. Most treatment-emergent adverse events were mild or moderate, and safety at 16 weeks persisted through 52 weeks.
The study investigators concluded, “Ixekizumab provided sustained and clinically meaningful improvement in the signs and symptoms of active r-axSpA for up to 52 weeks in COAST-V and COAST-W, with a high rate of completion. The safety findings were consistent with the known safety profile of ixekizumab. These findings suggest that ixekizumab could be a treatment option for axSpA in patients who are bDMARD-naive or who have had a prior inadequate response or intolerance to TNFi.”
Disclosure: The clinical trials were supported by Eli Lilly and Company. Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Dougados M, Wei JC-C, Landewé R, et al; COAST-V and COAST-W Study Groups. Efficacy and safety of ixekizumab through 52 weeks in two phase 3, randomised, controlled clinical trials in patients with active radiographic axial spondyloarthritis (COAST-V and COAST-W) [published online November 4, 2019]. Ann Rheum Dis. doi:10.1136/annrheumdis-2019-216118