What is the best biologic treatment for ankylosing spondylitis?

Best Biologic Treatment for Ankylosing Spondylitis

TNF inhibitors are the first-line biologic treatment for ankylosing spondylitis (AS) in patients who have failed NSAIDs, with no specific TNF inhibitor showing clear superiority over others for overall disease control. 1

First-Line Biologic Treatment Algorithm

1. Initial biologic choice: TNF inhibitors

   • Indicated for patients with active AS who have failed treatment with at least 2 different NSAIDs over 1 month, or had incomplete responses to at least 2 different NSAIDs over 2 months 1
   • Options include: adalimumab, certolizumab, etanercept, golimumab, and infliximab
   • Strong recommendation based on high-quality evidence 1

2. Special clinical considerations for TNFi selection:

   • For patients with recurrent uveitis: Choose monoclonal TNF antibodies (adalimumab or infliximab) over etanercept 1
   • For patients with inflammatory bowel disease: Choose monoclonal TNF antibodies (infliximab, adalimumab, certolizumab for Crohn's, or infliximab, adalimumab, golimumab for ulcerative colitis) 1

3. Second-line biologic options: IL-17 inhibitors

   • Secukinumab or ixekizumab are strongly recommended if TNFi fails 1
   • FDA-approved for treatment of active AS 2
   • Caution: Avoid in patients with inflammatory bowel disease as they may exacerbate Crohn's disease 1

Treatment Failure Management

1. Primary non-response to first TNFi:

   • Switch to IL-17 inhibitor (secukinumab or ixekizumab) 1

2. Secondary non-response to first TNFi:

   • Switch to a different TNFi 1
   • Evidence shows improvement in clinical outcomes when switching between TNFi agents, though response may be less robust than primary response 1

3. Avoid adding conventional DMARDs:

   • Adding sulfasalazine or methotrexate to TNFi is not recommended 1
   • Conventional DMARDs have limited efficacy in axial disease 3

Comparative Efficacy

Recent network meta-analyses have provided insights into comparative effectiveness:

• Infliximab has shown the highest probability for achieving ASAS20 response at both 12 and 24 weeks among all biologics 4
• Among subcutaneous options, golimumab achieved the highest probability for ASAS20 response at 12 weeks 4
• TNF-α inhibitors appear superior to both IL inhibitors and JAK inhibitors for rapid disease control 5

Safety Considerations

• Pre-treatment screening:

  • Test for latent tuberculosis before initiating any biologic therapy 2
  • Complete age-appropriate vaccinations 2

• Monitoring:

  • Regular assessment of disease activity and potential adverse effects
  • Continued TB screening during treatment

• Common adverse events:

  • Injection site reactions (more common with etanercept) 1
  • Development of antinuclear antibodies (more common with infliximab) 1
  • Increased risk of infections, particularly upper respiratory tract infections 1

Key Pitfalls to Avoid

1. Don't use systemic glucocorticoids - strongly recommended against in AS 1

2. Don't delay biologic therapy in patients with active spinal disease who have failed NSAIDs, as DMARDs have limited efficacy for axial symptoms 3

3. Don't use etanercept in patients with recurrent uveitis or inflammatory bowel disease 1

4. Don't use IL-17 inhibitors in patients with inflammatory bowel disease due to risk of exacerbation 1

5. Don't continue ineffective therapy - if inadequate response after 3-6 months, switch to a different mechanism of action 1