Tocilizumab & Abatacept Effective in Giant Cell Arteritis Save

Giant cell arteritis (GCA) is a medium and large vasculitis, wherein only glucocorticoids (GC) treatment has been the mainstay of therapy. As many will require prolonged treatment, the hazards of GC are well known, lead to substantial toxicity and morbidity.

Targeting IL-6 with tocilizumab (TCZ) has been shown to be effective in uncontrolled reports. Adler and colleagues (late breaking abstract 1) from Bern conducted a single-center, randomized, placebo-controlled trial evaluating TCZ in 30 patients with newly diagnosed or recurrent GCA. Patients were randomized 2:1 to receive tocilizumab 8 mg/kg IV or IV placebo. All received high dose oral GC that was weaned per protocol down over 16 weeks.

The primary end point was remission at 12 weeks; this was achieved in 17/20 on TCZ but only 4/10 on placebo. Secondary endpoints included relapse free status at week 52. There were more relapses in the PBO group (8/10) than the TCZ treated patients (3/20) at 6 months. At the end of the trial, 20% and 85%, respectively, had not had a relapse. There were numerous serious adverse events (SAE) in both arms - 7/20 in the tocilizumab arm and 5 in the placebo arm. Most of these were related to high dose steroid use; 1 death occurred in the placebo arm due to myocardial infarction.

Another report from Landford (LB poster 9L) also studied 49 GCA patients starting on high dose GC and were randomized to receive either abatacept (ABA) or placebo (PBO). Relapse free survival was seen in 48% of ABA and 31% of PBO treated patients (p0.05). No differences in SAE were noted.

These early preliminary reports have shown the steroid sparing potential and success of using either TCZ or ABA biologic therapy in patients with newly diagnosed GCA. Larger controlled trials are underway to confirm these findings.