Pathophysiology of large vessel vasculitis and utility of interleukin-6 inhibition therapy

Area of Science:

• Rheumatology
• Immunology
• Vascular Medicine

Background:

• Takayasu arteritis (TAK) and giant cell arteritis (GCA) are large- and medium-sized artery vasculitides.
• Refractory cases involve progressive vascular remodeling and severe outcomes.
• Interleukin-6 (IL-6) is implicated in TAK and GCA pathophysiology.

Purpose of the Study:

• To evaluate the efficacy of IL-6 inhibition therapy, specifically tocilizumab (TCZ), in TAK and GCA.
• To explore the potential of TCZ in preventing vascular remodeling beyond symptom and inflammatory marker control.
• To address the need for a "treat to target" strategy in managing these conditions with TCZ.

Main Methods:

• Review of randomized controlled trials on tocilizumab (TCZ) for IL-6 inhibition.
• Analysis of TCZ's impact on vascular remodeling in TAK and GCA.
• Consideration of safety profiles, particularly infection risks associated with combination therapy.

Main Results:

• Tocilizumab (TCZ) demonstrated significant therapeutic effects in recent trials.
• TCZ offers a new approach to managing arterial changes, moving beyond traditional symptom and marker reduction.
• Combination therapy with glucocorticoids (GCs) and TCZ increases infection risk, necessitating GC dose tapering.

Conclusions:

• Tocilizumab (TCZ) is a promising therapy for Takayasu arteritis (TAK) and giant cell arteritis (GCA).
• Establishing a "treat to target" strategy is crucial for preventing vascular remodeling with TCZ.
• Careful monitoring for infections and minimizing glucocorticoid (GC) dosage are essential when using TCZ.