Superior Renal Protection: Tocilizumab Emerges as Leader in AA amyloidosis Treatment, study finds

Biologic disease-modifying anti-rheumatic drugs (bDMARDs) reduce systemic inflammation in several diseases, leading to a reduction of proteinuria and prevention of ESRD, the study stated. The findings were published in the Annals of the Rheumatic Diseases.

Among 83 patients undergoing biologic therapy for their underlying conditions and diagnosed with renal AA amyloidosis, between 60% to 88% did not progress to end-stage renal disease (ESRD) over an average follow-up period of 5 years, the researchers reported.

"Additionally, tocilizumab (Actemra), an anti-interleukin-6 drug, demonstrated greater efficacy compared to other biologics like tumor necrosis factor (TNF) inhibitors."

Serum amyloid alpha (SAA) amyloidosis (AA) can arise from chronic inflammatory diseases (CID+AA), autoinflammatory syndromes (Auto+AA), or idiopathic origins (Idio+AA). The predominant organ affected is the kidneys, with potential progression to end-stage renal disease (ESRD) and multiple organ failure. Peter Kvacskay, Department of Hematology, Oncology, and Rheumatology, Heidelberg University Hospital, Heidelberg, Germany, and colleagues aimed to analyze laboratory and clinical parameters at baseline and during follow-up. All patients were treated with biological disease-modifying antirheumatic drugs.

For this purpose, the researchers conducted a single-center retrospective analysis of renal outcomes and survival in patients with CID+AA (n=34), Auto+AA (n=24), and Idio+AA (n=25) treated with cytokine-inhibiting bDMARDs.

The study led to the following findings:

• Eighty-three patients with renal AA were identified and followed for a mean observational period of 4.82 years.
• C reactive protein (CRP), serum amyloid alpha, and proteinuria were significantly reduced with bDMARD therapy. Progression to ESRD was prevented in 60% (cid+AA), 88% (auto+AA), and 81% (idio+AA) of patients.
• Tocilizumab was given to 34 patients with cid+AA and idio+AA and was more effective in reducing CRP and progression to ESRD and death compared with other bDMARDs.

According to the authors, the study is the first comprehensive study to show the safety and efficacy of bDMARD treatment in renal AA amyloidosis, evaluating three distinct etiological subgroups: chronic inflammatory diseases and AA amyloidosis (CID+AA), autoinflammatory syndrome and AA amyloidosis (Auto+AA), and idiopathic AA amyloidosis (Idio+AA). The study includes a substantial number of patients with an average follow-up period of 4.82 years.

"In patients with Auto+AA, IL-1 inhibition has demonstrated notable clinical effectiveness and safety, while tocilizumab has shown superior efficacy compared to other bDMARDs in CID+AA and Idio+AA. These findings recommend the preferential use of IL-1 inhibitors and tocilizumab based on the specific underlying diseases in the treatment of AA amyloidosis," they concluded.

Reference:

Kvacskay P, Hegenbart U, Lorenz H, et albDMARD can prevent the progression of AA amyloidosis to end-stage renal disease. Annals of the Rheumatic Diseases Published Online First: 23 April 2024. doi: 10.1136/ard-2023-225114