NEJM: Actemra Effective in Giant Cell Arteritis Save

On May 22, Genentech received FDA approval for the use of subcutaneous (sc) tocilizumab (TCZ) in patients with giant cell arteritis (GCA) – also known as temporal arteritis. This new indication is largely based on the landmark GiACTA study presented at the annual ACR meeting in November 2016. The results are now published in the New England Journal of Medicine (NEJM). 

The phase III GiACTA study was a 52-week, Phase randomized, double-blind, placebo-controlled trial that included 251 patients, from 14 countries, with either newly diagnosed or relapsing GCA. All patients received initial prednisone (that was tapered over 26 or 52 weeks); half were on placebo and the other half received TCZ 162 mg (either weekly or every other week) in addition to prednisone. The primary endpoint was sustained remission from week 12 to week 52.

Patients treated with TCZ had sustained remission in 56 % of patients receiving weekly TCZ and 53% receiving every-other week dosing (compared to 18% of placebo treated patients at 52 weeks). Time to first flare following clinical remission was significantly later in both TCZ treated groups compared to placebo. Impressively, 56% of TCZ patients were in steroid-free disease remission at one year, compared to 14% for those on steroid only taper regimen. 

Patients receiving TCZ had less prednisone exposure over the 52-week period; 1862 mg in the TCZ groups, compared to 3296 - 3818 mg in the placebo groups.

Serious adverse events occurred in 14-15% of TCZ patients and 22-25% of those in the placebo group. The rate is serious infections in GiACTA was events was 9.7 per 100 patient years in the Actemra weekly group and 4.4 per 100 patient years in the every other week Actemra group. There were no bowel perforations noted in the trial.

GiACTA is a 3 year study and the open-label portion is ongoing.