Synergistic Improvements in Synovitis, Enthesitis, and Patient-Reported Outcomes for Patients with Psoriatic Arthritis Treated with Ixekizumab in SPIRIT Trials

IntroductionSynovitis and enthesitis are key manifestations in psoriatic arthritis (PsA). This descriptive analysis investigated the association between improvement in synovitis and enthesitis, individually and combined, and improvement in patient-reported outcomes (PROs) including health-related quality of life (HRQoL) for patients with PsA from the SPIRIT-P1, SPIRIT-P2, and SPIRIT-H2H trials who presented with synovitis and enthesitis at baseline and received ixekizumab (IXE) treatment. MethodsIn this post hoc analysis, data are presented from patients with PsA treated with IXE every 4 weeks from two phase III studies (SPIRIT-P1 and SPIRIT-P2) and one phase IIIb/IV study (SPIRIT-H2H) who had both synovitis and enthesitis at baseline. Associations between improvements in synovitis and improvements in enthesitis were explored using Pearson analyses through week 52. Associations between improvements in both, either, and neither condition with improvements in PROs (36-item Short Form Health Survey Physical Component Score [SF-36 PCS], the European Quality-of-Life 5 Dimensions 5 Levels [EQ-5D-5L] including the EQ-5D Visual Analogue Score [VAS] and the EQ-health index, Patient's Global Assessment [PtGA], and pain VAS) were assessed descriptively through week 52. ResultsResults demonstrated the synergistic improvements in synovitis and enthesitis, individually or combined, and improvements in PROs including HRQoL, for patients treated with IXE through week 52. An association between improvements in synovitis and enthesitis symptoms was observed through week 52. Patients who achieved resolution of both synovitis and enthesitis reported highest improvements in SF-36 PCS, EQ-5D-5L, pain VAS, and PtGA. ConclusionSynergistic improvements in two key PsA domains, namely synovitis and enthesitis, and improvements in PROs including HRQoL, were observed for patients with PsA treated with IXE through week 52. These findings support PsA treatment goal aiming to achieve the lowest possible level of disease activity in all disease domains. Trial registration numbersSPIRIT-P1 (NCT01695239), SPIRIT-P2 (NCT02349295), and SPIRIT-H2H (NCT03151551).