Safety and efficacy of empirical interleukin-1 inhibition using anakinra in AA amyloidosis of uncertain aetiology

Objective: AA amyloidosis is a serious complication of persistent inflammation, which, untreated will progress to renal failure and death. Effective suppression of the underlying inflammatory disease is the focus of treatment. However, in approximately 20% of cases the underlying condition remains uncertain, presenting a dilemma as to choice of treatment.

Methods: We conducted a retrospective study of a cohort of 11 patients diagnosed with AA amyloidosis of unknown aetiology, who had been empirically treated with anakinra.

Results: In anakinra-responders, median pre-treatment SAA was 74 (IQR 34–190) mg/L, and median on-treatment SAA was 6 (4–16) mg/L (p = .0047), with the response having been maintained for a median on-treatment follow-up of 1.8 (1–7.6) years. Six dialysis patients were treated effectively and safely with 100 mg anakinra three times weekly post-dialysis. Four patients remained well on daily anakinra post-renal transplant. Five anakinra-responders showed regression and three showed stabilization of amyloid load on serial SAP scintigraphy.

Conclusions: This small cohort shows that even in potentially high risk cases with organ damage secondary to AA amyloidosis or in the presence of a renal graft, anakinra, when used appropriately and carefully monitored, has proved remarkably effective and well tolerated. Longer follow-up of this off-label use is required.