Long-term follow-up of secondary amyloidosis patients treated with tumor necrosis factor inhibitor therapy

There are no treatment modalities, which were proven to prevent the deposition of amyloid, proteinuria, and loss of renal function due to amyloidosis. Anti-tumor necrosis factor agents (anti-TNFs) were shown to decrease the production of serum amyloid A protein.We aimed to evaluate the long-term efficacy and safety of anti-TNFs in secondary (AA) amyloidosis patients treated in a single center.Thirty-seven patients with AA amyloidosis were started an anti-TNF for AA amyloidosis between March 2001 and June 2008 and followed until May 2016 unless deceased. They were surveyed for the endpoints of death, development of end-stage renal disease (ESRD), switch to another agent due to worsening of amyloidosis and adverse events.Among the 37 patients, 12 (32%) had died, 9 (24%) had ESRD, and 8 (22%) had started another group of biologic due to worsening of amyloidosis indicated by an increase in proteinuria, 5 (14%) patients are still doing well with anti-TNFs, and 3 (8%) are off treatment at the end of a median follow-up of 10 (interquartile range [IQR]: 5.5-10.5) years since the start of anti-TNFs and 10 (IQR: 8-13) years since the diagnosis of AA amyloidosis. Most common serious adverse events were sepsis and thrombotic events observed in 8 and 4 patients, respectively.Treatment with anti-TNFs may be associated with a higher survival rate compared with historic cohorts of AA amyloidosis, especially when started early with a lower serum creatinine level at baseline. Caution is needed regarding serious adverse events, especially infections.