From Medscape Prof Jonathan Kay Professor of medicine at the University of Massachusetts Medical School.
Tocilizumab, an interleukin (IL)-6 receptor inhibitor in giant cell arteritis. This study was an efficacy and safety study looking at tocilizumab in patients with documented giant cell arteritis to see whether tocilizumab improved the remission of patients after tapering from glucocorticoid therapy. The patients were studied for 52 weeks, and patients who were at least 50 years of age who had giant cell arteritis confirmed by temporal artery biopsy or cross-sectional imaging with elevation of acute-phase reactants that was attributable to giant cell arteritis were randomly assigned 1:1:2:1 into four groups.
The first group was treated with a short course of prednisone over 26 weeks, which was tapered, and they were given a weekly subcutaneous placebo. The second group received a long course of prednisone tapered over 52 weeks, again, with a weekly subcutaneous placebo. The third group received weekly subcutaneous tocilizumab at the usual dose of 162 mg and a 26-week short-course prednisone taper. The fourth group received an every-other-week dose of tocilizumab subcutaneously at 162 mg and a short-course prednisone taper over 26 weeks. The randomization allowed twice as many patients to be entered into the weekly subcutaneous tocilizumab arm as into the other three arms.
Patients who flared or could not adhere to the protocol-defined tapering schedule received open-label prednisone as an escape therapy but continued on their double-blinded tocilizumab or placebo. Sustained remission was the primary outcome, and it was defined at week 52 as the absence of flare and normalization of the C-reactive protein after week 12, combined with adherence to the protocol-defined prednisone taper. The patients who were the proportion of patients in sustained remission, comparing the combined groups on tocilizumab with the short-course prednisone group and the long-course prednisone group, respectively, were considered primary and key secondary endpoints of this study.
The study was a positive study. It showed that the addition of tocilizumab to a 26-week prednisone taper was superior to both short- and long-course tapers without concomitant tocilizumab therapy in achieving sustained remission at 52 weeks. This addition of tocilizumab also allowed a reduction in the total cumulative prednisone dose. From this study, it looks as if tocilizumab will be an effective adjunct to prednisone in the treatment of giant cell arteritis, sparing prednisone and also leading to a larger proportion of patients achieving remission without flares and with normalization of their acute-phase reactants.
This certainly is going to change therapy. However, the cost of tocilizumab compared with the cost of prednisone alone is something that will have to be considered in the treatment of these patients. The potential adverse outcomes of inadequately treated giant cell arteritis, however, certainly justify the use of an effective medication regardless of its cost.