Ixekizumab bests adalimumab in PsA in head-to-head comparison
Ixekizumab was associated with superior efficacy outcomes compared to adalimumab in a cohort of DMARD-naive patients with active psoriatic arthritis, according to findings presented at the EULAR Annual Congress.
“The key initial point is that this is the first head-to-head between true biologics in PsA,” Philip J. Mease, MD, of Swedish Medical Center and the University of Washington, in Seattle, told Healio Rheumatology in an interview. “There were previous trials in which adalimumab was used as a reference arm, but those trials were not specifically designed or powered to demonstrate superiority or noninferiority between agents.”
The study included 283 patients each randomly assigned to ixekizumab (Taltz, Eli Lilly) or adalimumab (Humira, AbbVie). Eligible participants had active PsA and plaque psoriasis, were DMARD-naive or had previously demonstrated an inadequate response to DMARD therapy. Study drugs were assigned for 52 weeks.
“We made the decision to use a novel primary endpoint, which is a combination of ACR50 — a high bar for joint response — simultaneously with PASI100 response, which is a complete clearance of psoriasis skin disease,” Mease said.
Primary endpoint results showed that ixekizumab bested adalimumab in the composite ACR50 and PASI100 outcome, 36% vs. 26% (P < .05). For ACR50 alone, the rates were 51% for ixekizumab and 47% for adalimumab, which Mease noted met noninferiority criteria. PASI100 rates were 60% for ixekizumab and 47% for adalimumab, which was also a noninferior result.
Regarding secondary endpoints, Mease highlighted improvements in ACR70 response, PASI75, PASI90, DAPSA remission, and minimal disease activity for the ixekizumab arm compared with the adalimumab arm. He also noted that ixekizumab was superior to adalimumab in the SPARCC enthesitis parameter, 57% vs. 45%.
“One area we really wanted to focus on is enthesitis, which impacts the heel, ribcage and kneecaps of PsA patients, which is a unique feature of PsA,” he said. “Ixekizumab showed superiority in this outcome.”
The safety profile showed no unexpected events for either drug.
Mease said that the researchers were confident that ixekizumab would meet the high standards set by the study design. “Ixekizumab has a very high degree of efficacy in skin manifestations of PsA, and comparable efficacy to adalimumab in arthritis response,” he said.
Regarding whether these findings could change clinical practice, Mease suggested that the picture remains complicated. “If insurance company and government decisions were no issue, a physician might well use ixekizumab over adalimumab because of this efficacy result,” he said, but noted that FDA approval and pharmacy benefit manager rebate systems are ongoing concerns. “For a while, there won’t be changes to the formularies, but at least this gives a clinician some evidence for using an IL-17 inhibitor over a TNF inhibitor.” – by Rob Volansky
Mease PJ, et al. LB0005. Presented at: EULAR Annual Congress; June 12-15, 2019; Madrid.
Disclosure: Mease reports associations with AbbVie, Amgen, Bristol-Myers Squibb, Celgene, Janssen, Leo, Eli Lilly, Galapagos, Genentech, Gilead, Leo, Merck, Novartis, Pfizer, Sun Pharmaceutical Industries, Inc., and UCB.