What is Giant Cell Arteritis (GCA)?

From the Guidelines

Giant cell arteritis (GCA) treatment should begin immediately with high-dose corticosteroids, typically prednisone 40-60mg daily, to prevent vision loss and other complications, as recommended by the 2021 American College of Rheumatology/Vasculitis Foundation guideline 1. The initial dose should be maintained for 2-4 weeks until symptoms resolve, followed by a gradual taper over 12-18 months. For patients with visual symptoms, methylprednisolone 500-1000mg IV daily for 3 days may be given before oral therapy. Tocilizumab, an IL-6 receptor antagonist, can be added as a steroid-sparing agent at 162mg subcutaneously weekly, as approved by the US Food and Drug Administration for the treatment of GCA 1. Low-dose aspirin (81mg daily) is often recommended to reduce the risk of ischemic complications. Diagnosis is confirmed with temporal artery biopsy, though treatment should not be delayed while awaiting results. Patients require regular monitoring for steroid side effects, including bone density assessment, vitamin D and calcium supplementation, and possibly bisphosphonates for osteoporosis prevention. GCA is an autoimmune condition where T-cells and macrophages infiltrate arterial walls, causing inflammation, narrowing, and potential occlusion, particularly affecting cranial arteries and the aorta. Some key points to consider in the management of GCA include:

• The importance of prompt treatment to prevent vision loss and other complications
• The use of high-dose corticosteroids as the initial treatment
• The potential addition of tocilizumab as a steroid-sparing agent
• The need for regular monitoring of steroid side effects
• The importance of considering comorbidities when assessing disease activity and selecting treatment, as recommended by the 2024 treat-to-target recommendations in giant cell arteritis and polymyalgia rheumatica 1. It is also important to note that the 2018 update of the EULAR recommendations for the management of large vessel vasculitis suggests that adjunctive therapy should be used in selected patients with GCA, such as those with refractory or relapsing disease, or those with an increased risk of GC-related adverse effects or complications 1. However, the most recent and highest quality study, the 2021 American College of Rheumatology/Vasculitis Foundation guideline, should be prioritized when making treatment decisions 1.

From the FDA Drug Label

1.2 Giant Cell Arteritis (GCA) ACTEMRA® (tocilizumab) is indicated for the treatment of giant cell arteritis (GCA) in adult patients.

Tocilizumab (IV) is indicated for the treatment of Giant Cell Arteritis (GCA) in adult patients 2.

From the Research

Giant Cell Arteritis (GCA) Treatment

• The main treatment for GCA is high-dose corticosteroid therapy, which should be started immediately in patients with suspected GCA and acute visual or neurologic symptoms 3, 4.
• Patients with GCA should be treated with high-dose intravenous methylprednisolone sodium succinate (250 mg intravenously every 6 hours) for 3 days, followed by oral prednisone (80 mg per day or 1 mg/kg) for 4 to 6 weeks 3.
• The treatment may begin directly with oral prednisone (80 mg per day or 1 mg/kg) in patients without acute visual or neurologic symptoms 3.
• Methotrexate has been shown to be effective in reducing the proportion of patients who experience at least one relapse and the cumulative dose of corticosteroid 5.
• Induction therapy with high-dose glucocorticoids has been shown to permit a shorter course of therapy and reduce the cumulative dose of oral prednisone 6.
• Low-dose aspirin may be beneficial for patients with ischemic complications or multiple cardiovascular risk factors, but its benefit-to-risk ratio needs to be further studied 7.
• Emerging evidence suggests that adjunctive therapy with tocilizumab, methotrexate, aspirin, angiotensin receptor blockers, and statins may be effective in treating GCA 4.

Treatment Considerations

• Patients with GCA require careful follow-up and periodic laboratory evaluations with erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) 3, 4.
• Corticosteroids should be tapered gradually over months, and supplementation with calcium, vitamin D, bisphosphonate therapy, antimicrobial prophylaxis, and initiation of a proton pump inhibitor or Histamine H2-receptor antagonist should be considered 3, 4.
• Recurrence of inflammation is common in GCA, and adjunctive immunomodulatory therapy may be considered in patients experiencing relapsing inflammation despite high doses of corticosteroids or those with corticosteroid-induced complications 4.