Taper versus discontinuation of tocilizumab in patients with giant cell arteritis: Real-world experience from a tertiary center

Introduction: Following the approval of tocilizumab (TCZ) for giant cell arteritis (GCA), recent studies have shown a high relapse frequency after abrupt discontinuation of TCZ. However, a thorough exploration of TCZ tapering compared to abrupt discontinuation has never been undertaken. Likewise, adverse events have only been scarcely investigated in routine care. This study aimed to compare the incidence of relapses in GCA patients undergoing TCZ tapering compared to abrupt discontinuation. Methods: We performed a single-center retrospective cohort study from 2012 to 2022. Data from GCA patients treated with TCZ was obtained from the Electronic Patients Record. Relapse-free survival is reported in Kaplan- Meier plots and tapering versus abrupt discontinuation were compared using a Wilcoxon-Brewlos-Gehan test. Results: We included 155 patients receiving TCZ treatment for GCA, of which 104 discontinued TCZ. Among the 104 patients discontinuing TCZ, 42 (40 %) experienced a relapse within the first year. A total of 57 patients underwent taper with 6/38 (16 %) and 2/19 (11 %) relapsing while receiving TCZ every second or third week, respectively. In comparison, 59 patients underwent abrupt discontinuation with 27 (46 %) relapsing during follow-up. The patients undergoing abrupt TCZ discontinuation demonstrated a significantly shorter time to relapse compared to all tapered patients (p = 0.02) as well as patients tapered from weekly TCZ treatment to every second week (p < 0.01). Furthermore, 15 % of patients discontinued TCZ due to adverse events. Conclusion: This is the first study indicating that TCZ taper induced longer relapse-free survival than abrupt discontinuation, implying that taper may be favored over discontinuation in patients with GCA.