The randomized, placebo (PBO)-controlled GiACTA trial demonstrated the efficacy and safety of tocilizumab (TCZ) in patients with giant cell arteritis (GCA). The present study evaluated the efficacy of TCZ in patients with GCA presenting with polymyalgia rheumatica (PMR) symptoms only, cranial symptoms only or both PMR and cranial symptoms in the GiACTA trial.
In GiACTA, 250 patients with GCA received either TCZ weekly or every other week plus a 26-week prednisone taper or PBO plus a 26- or 52-week prednisone taper. This post hoc analysis assessed baseline characteristics, sustained remission rate, number of flares, annualized flare rate, time to flare, cumulative prednisone dose, methotrexate use and safety in patients with PMR symptoms only, cranial symptoms only or both at baseline.
Overall, 52 patients had PMR symptoms only, 94 had cranial symptoms only and 104 had both symptoms at baseline. At Week 52, rates of sustained remission were significantly higher with TCZ vs PBO in all 3 groups (PMR only, 45.2% vs 19.0%, P = 0.0446; cranial only, 60.3% vs 19.4%, P = 0.0001; PMR and cranial, 55.0% vs 11.4%, P < 0.0001). Smaller proportions of TCZ-treated patients experienced disease flare than PBO-treated patients across all groups (PMR only, 41.9% vs 57.1%; cranial only, 20.7% vs 47.2%; PMR and cranial, 31.7% vs 81.8%). Annualized flare rate and risk of flare were significantly lower with TCZ vs PBO for patients with cranial symptoms only and both symptoms; they were numerically lower, but did not reach statistical significance, in the smaller group of patients with PMR symptoms only.
TCZ improved clinical outcomes in patients who presented with PMR symptoms only, cranial symptoms only or both at baseline, suggesting that TCZ is effective in patients with GCA regardless of the presenting clinical phenotype.