Factors Affecting Efficacy of Secukinumab in Psoriatic Arthritis and Axial Spondyloarthritis

Treatment options for psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA) are increasing, and with studies already identifying response predictors for tumor necrosis factor inhibitors, there is a need to predict response to the interleukin (IL)-17A inhibitor secukinumab.¹

An abstract presented at the European League Against Rheumatism’s annual meeting identified demographic or clinical factors at the beginning of treatment with secukinumab for PsA and AxSpA that are associated with stopping the treatment due to inefficacy. The used a retrospective analysis of rheumatology patient notes in Glasgow, Ireland.

A total of 266 patients with PsA and 76 patients with AxSpA in Glasgow received secukinumab, with 48 of the PsA patients and 13 of the AxSpA patients discontinuing due to inefficacy.

Patients with PsA who discontinued due to inefficacy had higher levels of current smoking, as well as erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP). Patients with AxSpA who stopped treatment due to inefficacy had higher mean Bath Ankylosing Spondylitis Disease Activity Index (8.47 vs 7.02, P = .007). However, there was no difference in mean ESR or CRP. Smoking did not show a significant difference in AxSpA, but the numbers were small and there was a higher level of smoking in the inefficacy group.

The findings suggest that smoking, ESR, and CRP “may be helpful in informing treatment decisions in PsA and AxSpA in the absence of therapeutic biomarkers,” the authors concluded.

In a separate abstract, researchers found that patients with PsA who are also obese may have a better response to secukinumab.² They retrospectively analyzed clinical data of 100 patients with PsA who were treated with secukinumab in a clinic in Spain. The patients were divided into 2 groups by body mass index (BMI).

In the normal weight group (BMI <25), 75% were female, the median age was 50.5, the median BMI was 22, and the median Disease Activity in Psoriatic Arthritis (DAPSA) score was 19.19. In the overweight/obese group (BMI ≥25), 48% were female, the median age was 54, the median BMI was 29, and the median DAPSA was 21.2.

After 6 months, the patients in the overweight/obese group had a better response to secukinumab compared with the patients in the normal weight group. An analysis of serum levels of IL-17in 20 patients who were obese and 20 patients who were not obese showed the patients who were obese had significantly higher serum levels of IL-17.

“These are the first data about clinical response to secukinumab in obese PsA patients,” the authors concluded. “Our results support the relevance of IL-17 in driving systemic inflammation in obese PsA patients, also providing evidence that obese patients may have a better response to secukinumab compared to non-obese patients.”

References

1. Tindell A, McGucken A, Batool S, Siebert S. Clinical predictors of secukinumab retention in a real world cohort of patients with psoriatic arthritis and axial spondyloarthritis. Presented at: EULAR 2020; June 3-6, 2020; Abstract FRI0363. https://ard.bmj.com/content/79/Suppl_1/779.1

2. Iacono D, Pantano I, Favalli EG, et al. Secukinumab efficacy in PsA patients is dependent on patients’ body mass index. Presented at: EULAR 2020; June 3-6, 2020; Abstract SAT0435. https://ard.bmj.com/content/79/Suppl_1/779.1