IL-17A Blockade in Psoriatic Arthritis and Axial Spondyloarthritis

Clinical evidence for IL-17A blockade in psoriatic arthritis and axial spondyloarthritis

IL-17A blockade with ixekizumab or secukinumab demonstrates robust and sustained efficacy for both psoriatic arthritis and axial spondyloarthritis, with clinically meaningful improvements in joint symptoms, axial manifestations, and skin disease, accompanied by an acceptable safety profile characterized primarily by increased mucocutaneous candida infections.

Abstract

IL-17A blockade demonstrates consistent efficacy across the spectrum of psoriatic arthritis and axial spondyloarthritis in multiple randomized controlled trials. In radiographic axial spondyloarthritis, ixekizumab achieved ASAS40 response rates of 48-52% at week 16 versus 18% with placebo, while secukinumab showed approximately 60% ASAS20 responses across trials. In non-radiographic axial spondyloarthritis, ixekizumab demonstrated ASAS40 rates of 30-40% versus 13-19% with placebo at weeks 16 and 52. For psoriatic arthritis, meta-analytic evidence shows pooled ACR20 response relative risks of 2.04 (95% CI: 1.79-2.33), with individual trials reporting ACR20 rates of 50-62% versus 17-30% with placebo at week 24. Skin manifestations improved substantially, with PASI 75 response rates of 69-75% versus 7.5% placebo at week 12. The safety profile was generally favorable, with treatment-emergent adverse event rates of 57-77% and low serious adverse event rates (6% or less).

Methods

We analyzed 10 sources from an initial pool of 200, using 7 screening criteria. Each paper was reviewed for 8 key aspects that mattered most to the research question.

Paper search

We performed a semantic search across over 138 million academic papers from the Elicit search engine, which includes all of Semantic Scholar and OpenAlex.

We ran this query: "Clinical evidence for IL-17A blockade in psoriatic arthritis and axial spondyloarthritis". The search returned 200 total results from Elicit.

Screening Criteria

• Population: Patients with psoriatic arthritis and/or axial spondyloarthritis.
• Intervention: IL-17A blockade therapy (secukinumab, ixekizumab, etc.).
• Study Design: Randomized controlled trial, clinical trial, systematic review, or meta-analysis.
• Clinical Outcomes: Disease activity measures, functional assessments, quality of life, radiographic progression, or safety outcomes.
• Age Group: Adult patients (≥18 years).
• Sample Size: Adequate sample size (≥10 participants) and is NOT a case report or case series.
• Publication Type: Full-text publication (not just conference abstract).

Joint Efficacy Outcomes

• Axial Spondyloarthritis Studies:
  The ixekizumab COAST-V trial in radiographic axial SpA demonstrated ASAS40 response rates of 52% (ixekizumab Q2W) and 48% (ixekizumab Q4W) at week 16. The non-radiographic axial SpA (COAST-X) showed ASAS40 responses at week 52 of 31% (Q2W) and 30% (Q4W).

In ankylosing spondylitis, the early proof-of-concept secukinumab trial achieved ASAS20 response rates of 59% versus 24% placebo at week 6. The MAXIMISE trial in PsA with axial manifestations reported ASAS20 responses at week 12 of 63% (secukinumab 300 mg) and 66% (150 mg).

Psoriatic Arthritis Studies

The ACR response rates showed secukinumab achieving ACR20 rates at week 24 of 50.0% (150 mg) and 50.5% (75 mg) versus 17.3% placebo. The SPIRIT-P1 trial of ixekizumab showed ACR20 responses of 62.1% (Q2W) at week 24 versus 30.2% placebo.

Skin Efficacy Outcomes

The SPIRIT-P1 trial showed PASI 75 response rates at week 12 of 75.3% (ixekizumab Q4W) versus 7.5% placebo, with responses observed as early as week 4.

Safety Profile

Overall Adverse Events and Infections

Treatment-emergent adverse event rates varied across studies. The overall adverse events were reported in 57% (placebo), 66% (ixekizumab Q4W), and 77% (ixekizumab Q2W).

The most common adverse events included nasopharyngitis, upper respiratory tract infections, and injection site reactions. Infections showed similar frequencies across treatment groups.

Candida and Opportunistic Infections

Candida infections occurred in 4.7% of patients receiving secukinumab 300 mg.

Serious Adverse Events

Serious adverse events were generally low. The MAXIMISE trial reported serious adverse events in 6% of secukinumab-treated patients.

Malignancies, Laboratory Abnormalities, and Other Safety Outcomes

Malignancy rates were low. NO increased risk of Grade 3 or 4 neutropenia was observed. The Naik meta-analysis found lower discontinuation rates in treated versus placebo groups, suggesting better tolerability.

Synthesis

The evidence demonstrates consistent efficacy of IL-17A blockade across the spectrum of psoriatic arthritis and axial spondyloarthritis, with distinctions based on disease phenotype and prior treatment exposure.