Abstract
Purpose :
To evaluate the efficacy and safety of tocilizumab, an IL-6 receptor-α inhibitor, in patients with new-onset or relapsing giant cell arteritis (GCA) in GiACTA, a randomized, double-blind, placebo-controlled trial.
Methods :
GCA patients aged ≥50 years were randomly assigned 2:1:1:1 to one of the following: weekly subcutaneous tocilizumab 162 mg+26-week prednisone taper (TCZ-QW); every-other-week subcutaneous tocilizumab 162 mg+26-week prednisone taper (TCZ-Q2W); placebo+26-week prednisone taper (PBO+26); placebo+52-week prednisone taper (PBO+52). Prespecified subgroup analysis was performed by disease-onset status (new-onset and relapsing) for the proportion of patients in sustained remission at week 52, cumulative prednisone dose, and time to flare.
Results :
Of 251 patients enrolled, 119 (47%) had new-onset and 132 (53%) had relapsing GCA, distributed evenly across treatment groups. Baseline prednisone dose was higher for new-onset patients than relapsing patients (Table). The proportion of patients achieving sustained remission was higher in the TCZ groups than the placebo groups regardless of disease onset, with more new-onset patients than relapsing patients achieving sustained remission (new-onset: TCZ-QW 59.6%, TCZ-Q2W 57.7%; relapsing: TCZ-QW 52.8%, TCZ-Q2W 47.8%; Table). New-onset and relapsing patients treated with TCZ-QW were at lower risk for disease flare than those treated with PBO+26; this was also true for new-onset patients in the TCZ-Q2W arm. In relapsing patients, the hazard ratio for the TCZ-Q2W group was almost double that for the TCZ-QW group compared with either placebo group (Table). Cumulative prednisone exposure was lower with TCZ than with placebo. Incidences of serious adverse events were similar between new-onset and relapsing patients (Table). No deaths and no vision loss occurred.
Conclusions :
The treatment effect of TCZ for achievement of sustained remission at 52 weeks, coupled with a reduction in cumulative prednisone doses (Arthritis Rheumatol 2016; 68[suppl 10]; abstract 911), is consistent regardless of disease-onset status. Numerically higher responses in new-onset patients and a higher relapse-free survival rate of relapsing patients treated with TCZ-QW may influence treatment decisions in clinical practice.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.