Measuring treatment effect on psoriatic arthritis-related domains: insights from the SPIRIT-H2H study at weeks 24 and 52.

INTRODUCTION

Improvements in both musculoskeletal and non-musculoskeletal manifestations are important treatment goals in psoriatic arthritis (PsA).

OBJECTIVE

These post hoc analyses determined whether additional benefits related to various PsA domains are observed in patients simultaneously achieving 50% improvement in American College of Rheumatology criteria (ACR50) and 100% improvement in Psoriasis Area Severity Index (PASI100), the primary endpoint of the SPIRIT-H2H study.

METHODS

Patients with active PsA and psoriasis in SPIRIT-H2H (N = 566) were categorised into two sets of four response groups irrespective of treatment allocation (approved dosages of ixekizumab or adalimumab): patients who simultaneously achieved ACR50 and PASI100 response, achieved ACR50 response only, achieved PASI100 response only, or did not achieve ACR50 or PASI100 response after 24 and 52 weeks of treatment. Patients achieving simultaneous ACR50 and PASI100 response were compared with the other patient response groups at the corresponding time point for efficacy and health-related quality of life (HRQoL) outcomes.

RESULTS

Patients simultaneously achieving ACR50 and PASI100 responses at week 24 or 52 showed higher rates of ACR70 response, minimal disease activity, Disease Activity in Psoriatic Arthritis ≤ 4, resolution of enthesitis and dactylitis, and HRQoL improvement at weeks 24 and 52, respectively, than the other corresponding response groups at both time points.

CONCLUSION

High levels of disease control, such as those obtained with simultaneous achievement of ACR50 and PASI100 response, were linked to better outcomes across a wide range of endpoints that are important for patients with PsA. Patients meeting this combined endpoint showed more comprehensive and thus greater control of disease activity. Trial registration NCT03151551 Key Points • Treatment goals for patients with psoriatic arthritis emphasise the importance of improving both musculoskeletal and non-musculoskeletal manifestations of the disease. • A combined endpoint considering both these manifestations, achievement of at least 50% improvement in American College of Rheumatology criteria and 100% improvement in Psoriasis Area Severity Index, was linked with achievement of a number of other endpoints relevant to psoriatic arthritis, including health-related quality of life that are important to patients with psoriatic arthritis. • Patients meeting the combined endpoint were more likely to achieve a disease state of remission, which is the stated aim of treatment for psoriasis.