What is the treatment for giant cell arteritis?

Treatment of Giant Cell Arteritis

The treatment of giant cell arteritis (GCA) should begin immediately with high-dose glucocorticoids, with consideration for adding tocilizumab as a glucocorticoid-sparing agent to improve outcomes and reduce relapse rates. 1

Initial Management

• GCA is a medical emergency due to the imminent risk of sight loss and other ischemic events, requiring immediate treatment even before diagnostic confirmation 1

• Treatment should not be delayed while awaiting diagnostic procedures such as temporal artery biopsy 1

• For patients without threatened vision loss:

  • Start with high-dose oral glucocorticoids (typically 1 mg/kg/day, maximum 60 mg/day) 1
  • Daily dosing is preferred over alternate-day schedules 1

• For patients with threatened vision loss or cranial ischemic symptoms:

  • Consider intravenous pulse glucocorticoids (typically methylprednisolone 250 mg every 6 hours for 3-5 days) followed by high-dose oral glucocorticoids 1, 2
  • This approach may help prevent further vision loss, though evidence shows conflicting results 1

Adjunctive Therapy

• Tocilizumab (FDA-approved for GCA) should be considered in combination with glucocorticoids 1, 3

  • Significantly reduces glucocorticoid requirements and flare rates 1
  • Administered as 162 mg subcutaneously weekly 3

• Methotrexate may be considered as an alternative glucocorticoid-sparing agent 1, 4

  • Can reduce relapse rates and cumulative glucocorticoid dose 4
  • Less robust evidence compared to tocilizumab 1

• For patients with critical or flow-limiting involvement of vertebral or carotid arteries, add aspirin 1, 2

Treatment Target and Monitoring

• The treatment target should be remission, defined as absence of clinical symptoms and systemic inflammation 1

• Monitor disease activity using:

  • Clinical symptoms (headache, jaw claudication, visual symptoms, PMR symptoms)
  • Laboratory markers (ESR, CRP) 1
  • Note that relapses may occur despite normal inflammatory markers 1

• Obtain baseline noninvasive vascular imaging to evaluate large vessel involvement 1

  • MR or CT angiography of neck/chest/abdomen/pelvis can detect large vessel involvement 1

Glucocorticoid Tapering

• Maintain initial high-dose glucocorticoids for approximately one month 1
• Taper gradually based on clinical symptoms and normalization of inflammatory markers 1, 2
• At 3 months, the glucocorticoid dose is typically between 10-15 mg/day 1
• Total duration of therapy is variable and can extend to several years 1

Management of Relapse

• For patients experiencing disease relapse while on moderate-to-high dose glucocorticoids:

  • Add a non-glucocorticoid immunosuppressive agent 1

• For relapse with symptoms of cranial ischemia:

  • Add a non-glucocorticoid immunosuppressive agent AND increase glucocorticoid dose 1
  • Tocilizumab is preferred over methotrexate in this scenario 1

Special Considerations

• Patients with GCA and PMR overlap may require more careful monitoring as PMR often occurs as a symptom of relapse in GCA 1
• Up to 60% of patients will experience one or more relapses during glucocorticoid tapering 1
• Bone protection therapy should be provided to all patients on long-term glucocorticoids 1
• Multidisciplinary collaboration is often needed, involving ophthalmologists, neurologists, and vascular specialists 1

Potential Complications to Monitor

• Visual loss occurs in 15-35% of patients, primarily before initiation of therapy 1
• If one eye is affected, risk for losing vision in the second eye is as high as 50% without treatment 1
• Other complications include stroke, tongue or scalp necrosis, and peripheral limb ischemia 1, 5
• Scalp necrosis is associated with higher incidence of vision loss (32%) and increased mortality 5