Maintenance of Remission After Tocilizumab Withdrawal in Patients With Glucocorticoid-Dependent Polymyalgia Rheumatica

Abstract

Objective: The SEMAPHORE trial evaluated the efficacy and safety of tocilizumab (TCZ) treatment in patients with glucocorticoid (GC)-dependent polymyalgia rheumatica (PMR). TCZ reduced GC dose and disease activity at week 24. This study aimed to assess relapse rates after stopping TCZ treatment in patients achieving remission at week 24.

Methods: In the randomized study, 101 patients received intravenous TCZ (8 mg/kg) or placebo for 24 weeks. Of the 49 patients treated with TCZ, 33 achieved the primary outcome (PMR activity score <10 and GC dose reduction of ≤5 mg/day or ≥10 mg). All 33 patients except one stopped TCZ treatment at week 24 and completed a visit at week 32, with optional follow-up visits every eight weeks until week 48. Relapse was defined as the failure of the primary composite outcome during follow-up or the need for one or more TCZ infusion. Results were analyzed using Kaplan-Meier curves.

Results: Among the 33 patients who received TCZ in remission at week 24, seven stopped follow-ups before week 48, and two of the remaining 26 patients (7.7%) sustained remission in the following six months. 24 (92.3%) of the total patients experienced a relapse. The median time to relapse was 15 weeks (interquartile range, 8-25 weeks).

Conclusion: Among patients with GC-dependent PMR in remission after a six-month TCZ treatment, only a minority of the patients remained relapse-free after TCZ discontinuation. This study suggests that a six-month treatment course is not long enough to withdraw the TCZ. Further studies are needed to determine the optimal TCZ treatment duration and strategies for cessation to prevent relapses.

Figure 1

Relapse‐free survival among patients with GC‐dependent PMR in remission after six months of treatment with tocilizumab. Remission was defined as a PMR‐AS <10 and daily GC dose of ≤5 mg/day or a daily GC dose decreased by ≥10 mg. Day 0 was the visit at week 24 in the SEMAPHORE trial. The last tocilizumab infusion was at week 20 in the SEMAPHORE study. GC, glucocorticoid, PMR, polymyalgia rheumatica; PMR‐AS, polymyalgia rheumatica activity score. Color figure can be viewed in the online issue, which is available at http://onlinelibrary.wiley.com/doi/10.1002/art.43221/abstract.