What is the treatment for Giant Cell Arteritis (GCA)?

Treatment for Giant Cell Arteritis (GCA)

For patients with newly diagnosed Giant Cell Arteritis, high-dose glucocorticoids (prednisone 40-60 mg/day) should be initiated immediately, with tocilizumab added as adjunctive therapy, especially in high-risk patients or those with cranial ischemic manifestations. 1

Initial Treatment Approach

Glucocorticoid Therapy

• First-line treatment: High-dose oral prednisone (40-60 mg/day) should be started immediately upon suspicion of GCA 2, 1
• Emergency cases: For patients with visual or severe neurologic symptoms, consider IV methylprednisolone 250-1000 mg/day for 3 days before transitioning to oral prednisone 1
• Do not delay treatment while awaiting temporal artery biopsy results, as delaying glucocorticoid therapy when visual symptoms are present is the strongest risk factor for permanent blindness 1

Adjunctive Therapy

• Tocilizumab (FDA-approved for GCA) should be added to glucocorticoid therapy, particularly for:
  • High-risk patients
  • Those with cranial ischemic manifestations
  • Patients with relapsing disease
  • Cases where glucocorticoid-sparing is desired 1, 3
• Tocilizumab is administered as 162 mg subcutaneously weekly 1, 3

Glucocorticoid Tapering

• After initial high-dose therapy (40-60 mg/day), maintain until symptoms resolve and inflammatory markers normalize 1
• Taper to 15-20 mg/day within 2-3 months 1
• Further taper to ≤5 mg/day after 1 year 1
• Complete treatment typically requires about 2 years 1

Monitoring

• Regular clinical assessment for disease activity is essential 2, 1
• Monitor inflammatory markers (ESR, CRP) regularly 1
• Important: Increases in inflammatory markers alone without clinical symptoms warrant closer monitoring but not necessarily treatment escalation 2, 1
• Long-term clinical monitoring is strongly recommended even during apparent remission 2

Management of Relapses

• For relapse with cranial ischemic symptoms: Add or increase nonglucocorticoid immunosuppressive agent (tocilizumab or methotrexate) and increase glucocorticoid dose 1
• For relapse with polymyalgia rheumatica symptoms: Increasing glucocorticoid dose alone may be sufficient 1
• Most relapses occur during glucocorticoid tapering, with rates of 34-75% reported in observational studies 1

Surgical Considerations

• For patients requiring vascular surgical intervention, high-dose glucocorticoids should be used during the periprocedural period if active disease is present 2, 1
• For severe GCA with worsening limb/organ ischemia, immunosuppressive therapy should be escalated before considering surgical intervention 1

Common Pitfalls to Avoid

1. Delaying treatment while awaiting biopsy results - treatment should be initiated immediately if GCA is suspected
2. Escalating immunosuppressive therapy based solely on increased inflammatory markers without clinical symptoms
3. Inadequate monitoring for glucocorticoid and tocilizumab-related adverse effects
4. Tapering glucocorticoids too rapidly, which can lead to disease relapse

Special Considerations

• Calcium and vitamin D supplementation should be provided with long-term glucocorticoid therapy to prevent osteoporosis
• Consider aspirin for patients with critical involvement of vertebral or carotid arteries 1
• Methotrexate may be used as an alternative glucocorticoid-sparing agent when tocilizumab is not suitable 1

Recent evidence suggests that more rapid glucocorticoid tapering regimens may be feasible in some patients, potentially reducing cumulative steroid exposure and associated adverse effects 4, but this approach should be undertaken with careful monitoring for disease relapse.