What is the initial treatment for psoriatic arthritis?

Initial Treatment for Psoriatic Arthritis

For patients with active psoriatic arthritis, initial treatment should begin with a conventional synthetic disease-modifying antirheumatic drug (csDMARD), with methotrexate being the preferred first-line agent, particularly in patients with relevant skin involvement. 1, 2

Treatment Algorithm

First-Line Therapy:

• NSAIDs: May be used for temporary relief of musculoskeletal signs and symptoms 1

  • Should not be the only therapy beyond 3 months if active disease persists 2
  • Effective for joint symptoms but not for skin lesions

• csDMARDs: Should be initiated rapidly in patients with active disease 1

  • Methotrexate: Preferred first-line DMARD, especially with significant skin involvement (15-25 mg/week) 1, 2
  • Alternative csDMARDs: Sulfasalazine, leflunomide 1

Disease Pattern Considerations:

1. Polyarticular disease: Rapidly initiate csDMARD, preferably methotrexate 1, 2
2. Oligoarticular disease: Consider csDMARD if poor prognostic factors present (structural damage, high ESR/CRP, dactylitis, nail involvement) 1, 2
3. Predominantly axial disease:
   • NSAIDs and physiotherapy as first-line 2
   • csDMARDs are NOT effective for axial manifestations 2
4. Enthesitis: Local glucocorticoid injections as adjunctive therapy 1

Second-Line Therapy (Inadequate Response to csDMARDs):

• Biologic DMARDs (bDMARDs): Consider when there is inadequate response to at least one csDMARD 1
  • TNF inhibitors: First choice among biologics 1, 2
  • IL-17 inhibitors: Consider when there is significant skin involvement 1, 2
  • IL-12/23 inhibitors: Alternative option, particularly with concomitant inflammatory bowel disease 1, 2

Third-Line Therapy:

• JAK inhibitors: Consider when there is inadequate response to at least one csDMARD and at least one bDMARD 1
• PDE4 inhibitors: Consider in patients with mild disease and inadequate response to at least one csDMARD 1

Monitoring and Assessment:

• Aim for remission or low disease activity 1
• Regular disease activity assessment using validated measures (DAS28, ACR criteria) 2
• Monitor for progression of joint damage with radiographs 2
• DMARD failure defined as treatment for >3 months with >2 months at standard target dose without adequate response 2

Important Considerations:

• Safety monitoring:

  • Screen for latent tuberculosis before initiating TNF inhibitors 2
  • Monitor liver enzymes with methotrexate, especially with risk factors (alcohol consumption, obesity, diabetes) 1

• Treatment goals:

  • Maximize health-related quality of life
  • Control symptoms
  • Prevent structural damage
  • Normalize function and social participation 1, 2

Caution:

• Systemic glucocorticoids should be used with caution at the lowest effective dose 1
• TNF inhibitors carry risks of serious infections and malignancies 2
• Cyclosporine should be limited to less than 12 consecutive months due to cumulative toxicity 2

The 2020 EULAR recommendations provide the most recent and comprehensive guidance for PsA treatment, emphasizing early intervention with csDMARDs, particularly methotrexate, followed by biologics if needed, with treatment decisions guided by disease activity and comorbidities 1.