Real-world effectiveness and safety of tocilizumab in the management of polymyalgia rheumatica: a retrospective study from the KEIO-PMR cohort.

Objective: This study aimed to evaluate the effectiveness and safety of tocilizumab in polymyalgia rheumatica (PMR) in the real world.

Methods: All consecutive patients diagnosed with PMR who visited Keio University Hospital between May 2012 and October 2022 were retrospectively reviewed. Patients were divided into three groups: the tocilizumab group, the immunosuppressant group without biological agents, and the glucocorticoid monotherapy group. We collected clinical data including relapse, glucocorticoid doses, and adverse events during follow-up.

Results: A total of 125 patients with PMR was included in the analyses, with a mean age of 73.6 years and 83 (66.4%) female. Among them, 52 (41.6%) were in the tocilizumab group, 23 (18.4%) in the immunosuppressant group, and 50 (40.0%) in the glucocorticoid group. The glucocorticoid group showed the lowest serum C-reactive protein level at diagnosis (P = 0.046). Tocilizumab extended the time to relapse, even when given to patients with a relatively refractory disease course, although relapse assessment was not independent of C-reactive protein levels. The time to glucocorticoid discontinuation was the shortest in the tocilizumab group (P < 0.001 for induction or re-induction, P = 0.08 for maintenance). Tocilizumab use, methotrexate use and the number of relapses were identified as significant predictors of achieving glucocorticoid-free status. Adverse events were not significantly different between the three groups.

Conclusion: Tocilizumab effectively reduced relapse rates and demonstrated glucocorticoid-sparing effects in patients with refractory PMR in the real world, with no significant safety issues. These results further support the existing evidence that tocilizumab may be a promising treatment option in real-world settings.