Research Tests Duration of Effect of Tocilizumab Among Patients With GCA
Testing the long-term effect of tocilizumab after discontinuation in patients with giant cell arteritis (GCA), researchers found the majority of patients treated for 1 year with tocilizumab sustained a drug-free remission for 2 years after cessation.
Patients who experience relapse after discontinuing tocilizumab can manage symptoms using tocilizumab, but must include prednisone in treatment due to an increased risk of vision loss.
GCA requires vigilant management to avoid relapse, as well as consistent treatment, which for some patients includes a combination of tocilizumab and a glucocorticoid. Data on long-term effects of the immunosuppressant drug are generally scarce.
Part 1 of the Giant Cell Arteritis Actemra (GiACTA) trial included 251 patients with GCA, who were randomly assigned to receive 162 mg tocilizumab once a week or every other week in combination with a 26-week prednisone taper; or placebo, combined with a prednisone taper over 26 or 52 weeks.
Patients who achieved clinical remission stopped injections at the conclusion of part 1, which was 1 year. At the investigators' discretion, treatment during part 2 could consist of no treatment or of tocilizumab, glucocorticoids, methotrexate, or combinations of these. This phase continued for 2 more years.
The objective of the trial were maintenance of efficacy of clinical remission, defined as absence of relapse as determined by the investigator; cumulative glucocorticoid dose required during the trial to maintain remission; and long-term safety.
Of the 81 patients who were assigned tocilizumab once a week in part 1 and achieved clinical remission after 1 year, 59 began part 2 of the study on no treatment. Of these 59 patients, 25 (42%) maintained drug-free clinical remission throughout part 2.
“Tocilizumab-based regimens restored clinical remission among patients who experienced relapse in part two and were treated (median time to remission: 15 days for 17 patients on tocilizumab alone; 16 days for 36 patients on tocilizumab plus glucocorticoids; and 54 days for the 27 patients on glucocorticoids alone.) No new or unexpected safety findings were reported over the full 3 years of the study,” the authors concluded.
Stone J, Han J, Aringer M, et al. Long-term effect of tocilizumab in patients with giant cell arteritis: open-label extension phase of the Giant Cell Arteritis Actemra (GiACTA) trial. The Lancet Rheumatology. Published March 19, 2021.