Anakinra for the Treatment of Severe Still's Disease Complicated With Macrophage Activation Syndrome
Jiaxian Guo, Haojie Xu, Weiwei Li, Ying Wang, Yi Zhang, Yuan Jia, Yuan An, Huaqun ZhuABSTRACT
Objective
To investigate the efficacy and safety of add‐on anakinra for severe Still's disease complicated by macrophage activation syndrome (MAS) in a real‐world setting.
Methods
Consecutive patients aged ≥ 16 years with Still's disease and MAS (HLH‐2004 criteria adapted for rheumatic diseases) who received anakinra 100 mg subcutaneously once daily were enrolled. Outcomes were CID, remission, and four EULAR/PReS‐aligned targets, assessed at baseline, Day 7, Week 4, Month 3, and Month 6. Glucocorticoid (GC) dose was standardized to prednisone‐equivalent mg/kg/day.
Results
Eight women (mean age 29.9 ± 12.8 years) were included, and anakinra was initiated at the time of MAS diagnosis in six patients, 2 months after MAS diagnosis in one and 2 months before MAS onset in one. Of the seven patients starting anakinra at or after MAS onset, all achieved Targets 1 and 2 and CID at a median of 1.5 months (range 1–5), and all maintained remission for ≥ 6 months; no severe adverse events were observed. Mean prednisone‐equivalent dose fell from 1.63 ± 0.59 to 0.16 ± 0.09 mg/kg/day ( p < 0.01). Four patients discontinued anakinra within 6 months for reasons of cost and access rather than disease flare.
Conclusion
Add‐on therapy with anakinra was associated with rapid achievement of EULAR/PReS targets, sustained remission, and substantial GC sparing in severe Still's disease‐associated MAS.