Higher Disease Control Linked to Better Outcomes for Patients With Psoriatic Arthritis

The post hoc analyses evaluated health-related quality of life and efficacy across 4 subgroups treated with either ixekizumab or adalimumab.

Patients with psoriatic arthritis (PsA) who achieved both Psoriasis Area Severity Index (PASI100) and American College of Rheumatology criteria (ACR50) were associated with better outcomes, including health-related quality of life (HRQoL), according to a study published in Springer.1

“To optimize the benefits of treatment and improve the HRQoL of patients with PsA, all symptoms need to be considered,” investigators stated. “Therefore, a number of unidimensional and multidimensional tools and treatment targets have been developed and validated to assess the musculoskeletal (articular and extra-articular) or non-musculoskeletal manifestations of PsA and the impact of disease on HRQoL.”

Investigators utilized data from SPIRIT-H2H (NCT03151551), a 52-week, multicenter, randomized, open-label study evaluating the safety and efficacy of ixekizumab compared with adalimumab. All patients met the Classification for Psoriatic Arthritis criteria, had active psoriasis (PsO), were biologic disease-modifying antirheumatic drug (bDMARD) naïve, and had an inadequate response to at least 1 conventional synthetic disease-modifying antirheumatic drug (csDMARD). Participants were able to continue any csDMARDs during the study. Patients were randomized into 2 sets of 4 response groups at Week 24: those achieving ACR50 and PASI100 (CR24), those achieving only ACR50 (JR24), those achieving only PASI100 (SR24), and those who did not achieve either (NR24). They were reallocated at Week 52 as well. Patients achieving both ACR50 and PASI100 were then compared with other response groups.

The post hoc analyses evaluated HRQoL and efficacy across the 4 groups. Assessments included Disease Activity in Psoriatic Arthritis (DAPSA), minimal disease activity (MDA), Leeds Enthesitis Index (LEI), Leeds Dactylitis Index-Basic (LDI-B), a Health Assessment Questionnaire-Disability Index (HAQ-DI), Nail Psoriasis Severity Index (NAPSI), a 36-Item Short Form Survey (SF-36), and a Dermatology Life Quality Index score (DLQI).

A total of 566 patients were included in the study, of which 283 received ixekizumab and 283 received adalimumab. At Week 24, 181 attained CR24, 94 attained JR24, 121 attained SR24, and 170 were placed in the NR24 cohort. At Week 52, 185 patients were reallocated into the CR52 group, 97 patients achieved JR52 criteria, 114 patients achieved SR52, and 170 were labeled NR52.

Patients who achieved both ACR50 and PASI100 during the study had HRQoL improvement, higher rates of ACR70 response, resolved enthesitis and dactylitis, had minimal disease activity and a Disease Activity in Psoriatic Arthritis score of ≤ 4 when compared with the other response groups at both Week 24 and Week 52.

The clinical and patient-reported outcomes at weeks 24 and 52 are as follows:

Musculoskeletal outcomes in patients achieving both ACR50 and PASI100 response (CR24 and CR52)

Patients in CR24 and CR52 had significantly (p < 0.05) higher rates of MDA and very low disease activity (VLDA) when compared with patients in other response groups. Additionally, DAPSA, HAQ-DI, and enthesitis resolution was higher in CR24 and CR52 compared with the other groups, especially with SR24, SR52, NR24, and NR52, respectively.

Musculoskeletal outcomes in patients achieving ACR50 response (JR24 and JR52)

A total of 48.9% and 60.8% achieved ACR70 at 24 and 52 weeks, respectively. MDA, VLDA< DAPSA, HAQ-DI, and enthesitis were higher in both JR24 and JR52 when compared with SR24, SR52, NR24, and NR52.

Musculoskeletal outcomes in patients achieving a PASI100 response (SR24 and SR52)

Patients in SR24 and SR52 achieved PASI75, PASI90, and PASI100 in significantly higher percentages when compared with JR24, JR52, NR24, and NR52.

Non-musculoskeletal outcomes

CR24 and CR52 had the highest rates of NAPSI compared with other groups (62.8% and 80.2%, respectively), with a statistically significant difference compared with NR24 and NR52. Those in JR24 and JR52 had the highest baseline PASI scores and most resolved nail symptoms (50.0% and 67.6%, respectively).

Comparison between Week 24 and Week 52 responses

Most (62.7%) patients in the CR52 cohort had already achieved ACR50 and PASI100 by Week 24. Of the other response groups, only 13.0% had an ACR50 and 15.1% had a PASI100 response within the same period. At Week 24, 51.5% achieved ACR50 in the JR52 group and 29.9% achieved PASI100 in the SR52 cohort.

The post hoc nature of the analysis limited the study. Further, a small number of patients were experiencing dactylitis at baseline, so LDI-B responses should be viewed with caution. Correlations between achievement of both ACR50 and PASI100 coupled with inhibition of structural damage could not be assessed as radiographic progression was not included in the SPIRIT-H2H trial.

“This analysis of data from the SPIRIT-H2H study showed that the primary endpoint of simultaneous achievement of an ACR50 and PASI100 response at week 24, irrespective of active treatment arm [and] similar findings were seen in week-52 analyses,” investigators concluded. “Patients meeting this primary endpoint are more likely to achieve a disease state of remission, which is the stated aim of PsA treatment according to GRAPPA and EULAR recommendations.”

Reference:

Behrens F, Leage SL, Sapin C, et al. Measuring treatment effect on psoriatic arthritis-related domains: insights from the SPIRIT-H2H study at weeks 24 and 52 [published online ahead of print, 2021 Sep 13]. Clin Rheumatol. 2021;10.1007/s10067-021-05891-5. doi:10.1007/s10067-021-05891-5