Abstract: Background: Aortitis is a frequent and potentially serious complication of giant cell arteritis (GCA). The phenotype associated with aortitis (GCA-aortitis) can present greater therapeutic challenges than the cranial-dominant phenotype. Tocilizumab (TCZ) is approved for GCA, although its efficacy in GCA-aortitis has not been specifically assessed in randomized controlled trials.
Objective: To assess the effectiveness and safety of TCZ monotherapy (TCZmono) compared with TCZ plus conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) (TCZcombo) in patients with GCA-aortitis in real-world practice, and to identify variables associated with imaging remission.
Methods: A multicenter observational study comparing TCZcombo versus TCZmono. Outcomes at 12 and 24 months included clinical remission, EULAR-defined remission, imaging remission, prednisone-sparing effect, and safety. Multivariable logistic regression identified factors linked to imaging remission at 24 months.
Results: A total of 196 patients (148 female, 48 male) with GCA-aortitis received TCZ (136 TCZmono, 60 TCZcombo). At 24 months, imaging remission was higher in the TCZcombo group (50.0%¦vs. 15.8%; p=0.026). No significant differences were found in clinical or EULAR-defined remission. TCZcombo demonstrated a prednisone-sparing effect. The serious adverse event (SAE) rate was numerically lower with TCZcombo (8.7 vs. 13.2 per 100 patient-years; p=0.21). TCZcombo increased the odds of imaging remission 5.26-fold (odds ratio [OR] 5.26; 95% confidence interval [CI]: 1.03-26.85; p=0.046).
Conclusion: In patients with GCA-aortitis, TCZcombo may be more effective than TCZmono in achieving imaging remission and promoting glucocorticoid tapering, but without definitive evidence regarding a reduction of serious adverse events.
