Nearly 9 in 10 children with juvenile PsA or ERA achieve ACR30 with ixekizumab

Treatment with ixekizumab resulted in almost 90 percent of children with active juvenile psoriatic arthritis (JPsA) or enthesitis-related arthritis (ERA) achieving an ACR30* response by week 16, according to the ongoing COSPIRIT-JIA trial presented at EULAR 2024.

“Ixekizumab, a high-affinity monoclonal antibody that selectively targets interleukin-17A, had previously demonstrated efficacy and an acceptable benefit–risk profile in adults with PsA and axial spondyloarthritis,” said lead author Dr Athimalaipet Ramanan from Bristol Royal Hospital for Children and Translational Health Sciences at the University of Bristol, Bristol, UK.

The phase III COSPIRIT-JIA trial included 101 paediatric patients (mean age 13.1 years, 43.6 percent female) with active juvenile idiopathic arthritis (JIA), 30.7 percent of whom were diagnosed with JPsA and 69.3 percent with ERA.

During the 16-week open-label treatment period, patients received subcutaneous ixekizumab Q4W** (n=81) or adalimumab Q2W*** (n=20), with dosing based on body weight. Participants in the ixekizumab arm were either biologic-naïve (n=60) or biologic-experienced (n=21), who were refractory or lack of response to biologics, whereas those in the adalimumab arm were all biologic-naïve.

Among patients treated with ixekizumab, 88.9 percent of patients achieved an ACR30 response by week 16 regardless of whether the patients were biologic-naïve (90 percent) or biologic-experienced (85.7 percent). [EULAR 2024, abstract LBA0009]

By contrast, 95 percent of biologic-naïve patients treated with adalimumab achieved an ACR30 response at week 16.

Of note, as early as week 16, a high proportion of patients treated with ixekizumab achieved ACR50 (79 percent), ACR70 (64.2 percent), ACR90 (29.6 percent), and ACR100 (18.5 percent) responses.

In terms of safety, treatment-emergent adverse events (TEAEs) occurred in 81.5 percent of patients on ixekizumab, which were all mild or moderate in severity.

There were three serious AEs reported. None were related to the study drug.

“Overall, in paediatric patients with JPsA and ERA, the efficacy of ixekizumab was demonstrated, … the pre-specified success criterion was met,” said Ramanan.

“The safety profile of ixekizumab in patients with JPsA and ERA was consistent with the known safety profile of the drug … in adults. Long-term safety is being awaited,” said Ramanan.