Efficacy of etanercept in patients with AA amyloidosis secondary to rheumatoid arthritis.
OBJECTIVE
The efficacy of biological therapies in rheumatoid arthritis (RA) is well known, but their hypothetical benefit in amyloid A (AA) amyloidosis secondary to RA still remains to be considered. We evaluated the efficacy and safety of etanercept in serum amyloid A (SAA) 1.3 allele Japanese patients with AA amyloidosis secondary to RA.


METHODS
Seven RA patients with histologically confirmed AA amyloidosis and renal involvement who were treated with etanercept were enrolled. They all had the SAA1.3 allele, which has been shown to be a risk factor not only for the association of AA amyloidosis but also for a poor prognosis in Japanese RA patients. Efficacy was assessed as a sustained decrease in RA inflammation and an amelioration of renal function.


RESULTS
RA inflammation and AA amyloidosis were improved and stabilized after 43.4 +/- 16.5 weeks. At week 20 the number of tender (p = 0.017) and swollen (p = 0.017) joints, and levels of serum C-reactive protein (p = 0.018) and albumin (p = 0.045) had improved. The values for SAA, serum creatinine, calculated creatinine clearance, and proteinuria also ameliorated. No severe adverse events were observed. One patient eventually had to go on hemodialysis but her tolerance of etanercept remained stable.


CONCLUSIONS
Etanercept can be used safely and effectively in AA amyloidosis secondary to RA with renal involvement, and is of clinical benefit in the short-term, even in patients on hemodialysis. It appears that SAA1.3 allele may be used as a clinical parameter for the introduction of etanercept in Japanese RA with AA amyloidosis.
Nakamura
T
T
Section of Internal Medicine and Rheumatology, Kumamoto Center for Arthritis and Rheumatology, Kumamoto, Japan. naktrkme@koh.marutakai.or.jp
Higashi
S
S
Tomoda
K
K
Tsukano
M
M
Baba
S
S
D000368:Aged; D000686:Amyloidosis / Q000188:drug therapy* / Q000209:etiology* / Q000235:genetics; D001172:Arthritis, Rheumatoid / Q000150:complications*; D002097:C-Reactive Protein / Q000032:analysis; D003404:Creatinine / Q000097:blood; D000068800:Etanercept; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000627:therapeutic use*; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D007674:Kidney Diseases / Q000150:complications; D008297:Male; D008875:Middle Aged; D018124:Receptors, Tumor Necrosis Factor / Q000627:therapeutic use*; D012189:Retrospective Studies; D012709:Serum Albumin / Q000032:analysis; D016896:Treatment Outcome
D007074:Immunoglobulin G; D007166:Immunosuppressive Agents; D018124:Receptors, Tumor Necrosis Factor; D012709:Serum Albumin; D002097:C-Reactive Protein; D003404:Creatinine; D000068800:Etanercept