What is the treatment for giant cell arteritis?

Treatment of Giant Cell Arteritis

The treatment of giant cell arteritis requires immediate initiation of high-dose oral glucocorticoids (prednisone 1 mg/kg/day, maximum 60 mg/day), with consideration of adding tocilizumab as a glucocorticoid-sparing agent, especially for patients at high risk of steroid-related complications. 1, 2

Initial Treatment

Patients without threatened vision loss:

• Start high-dose oral glucocorticoids (prednisone 1 mg/kg/day, maximum 60 mg/day) immediately upon clinical suspicion, even before biopsy confirmation 1, 2
• Consider adding tocilizumab (FDA-approved for GCA) as first-line therapy with glucocorticoids to reduce cumulative steroid exposure 1, 3
• Alternative option: methotrexate with glucocorticoids if tocilizumab is contraindicated 1, 2
• Daily dosing is preferred over alternate-day schedule for better remission rates 1

Patients with threatened vision loss:

• Administer intravenous pulse methylprednisolone (500-1000 mg/day for 3 days) immediately, followed by high-dose oral prednisone 1, 4
• This is a neuro-ophthalmic emergency - do not delay treatment while awaiting biopsy results 4, 5
• Visual loss occurs in 15-35% of patients with GCA, primarily before initiation of therapy 4
• Without treatment, risk of vision loss in the second eye is as high as 50% if one eye is already affected 4

Glucocorticoid Tapering

• Maintain initial high-dose glucocorticoids for approximately one month to ensure disease control 2, 6
• Begin gradual taper after 2-4 weeks of high-dose therapy, aiming for 10-15 mg/day by 3 months 2
• Guide tapering by clinical symptoms and normalization of inflammatory markers (ESR, CRP) 1, 2
• The median time to reach lowest maintenance dose may be up to 48.7 months in some patients 6
• Relapses are common during tapering; adjust based on symptoms and inflammatory markers 1, 6

Adjunctive Therapy

• Tocilizumab (162 mg SC weekly) is FDA-approved for GCA and has significant glucocorticoid-sparing effects 1, 3
• Methotrexate (10-15 mg/week) can be considered as an alternative steroid-sparing agent 1, 7
• Low-dose aspirin (75-150 mg/day) is recommended for all patients without contraindications to reduce risk of ischemic complications 1, 7
• Provide appropriate prophylaxis for glucocorticoid-related adverse effects (e.g., bone protection) 2, 5

Management of Relapses

• For relapses with cranial ischemic symptoms: add a non-glucocorticoid immunosuppressive agent (preferably tocilizumab) and increase glucocorticoid dose 1, 2
• For relapses with polymyalgia rheumatica symptoms only: increasing the glucocorticoid dose alone may be sufficient 1
• For patients with increased inflammatory markers but no symptoms: clinical observation and monitoring without escalation of therapy is recommended 1, 2

Monitoring

• Implement long-term clinical monitoring for all patients, even those in apparent remission 1
• Monitor ESR and CRP regularly as these are the most reliable parameters to guide therapy 1, 6
• Obtain baseline noninvasive vascular imaging to evaluate large vessel involvement 1
• For patients with large vessel involvement, periodic imaging may help assess disease activity 1

Special Considerations

• For patients with severe GCA and worsening signs of limb/organ ischemia: escalate immunosuppressive therapy over surgical intervention 1
• For patients requiring vascular surgical intervention: use high-dose glucocorticoids during the periprocedural period if active disease is present 1
• Collaborative decision-making between vascular surgeon and rheumatologist is essential for any patient requiring surgical vascular intervention 1

Treatment Duration

• Most patients require at least 1-2 years of therapy 8, 5
• Only a small percentage of patients (approximately 7%) may be able to completely stop therapy while maintaining stable inflammatory markers 6
• Long-term, low-dose maintenance therapy may be necessary for some patients with chronic-relapsing disease 8