IgG and IgM anticardiolipin antibodies following treatment with infliximab plus methotrexate in patients with early rheumatoid arthritis.
OBJECTIVE
To assess the occurrence of anticardiolipin antibodies (aCL) in patients with early rheumatoid arthritis (RA) receiving treatment with infliximab plus methotrexate (MTX) versus MTX alone.


METHODS
The first 299 patients enrolled in the randomized, Active-Controlled Study of Patients Receiving Infliximab for the Treatment of Rheumatoid Arthritis of Early Onset (ASPIRE) trial who had baseline (week 0) samples available for aCL testing were included in this study. Sera were collected at weeks 0, 30, and 54 from 110 patients taking infliximab 3 mg/kg plus MTX, 98 patients taking infliximab 6 mg/kg plus MTX, and 91 patients taking placebo plus MTX. IgG and IgM aCL were measured using an anticardiolipin assay.


RESULTS
IgG and IgM aCL positivity at baseline was similar in all treatment groups. Most patients were negative for IgG aCL at baseline and remained so at the last followup evaluation. One percent (2 of 208) of patients who received infliximab plus MTX and were negative for IgG aCL at baseline were positive for IgG aCL at weeks 30 and 54. A slightly higher proportion of patients who received infliximab plus MTX and were negative for IgM aCL at baseline were positive for IgM aCL at weeks 30 and 54 (4.8% [10 of 208]) as compared with patients who received placebo plus MTX (1.1% [1 of 91]), but the difference was not significant.


CONCLUSIONS
There was a low incidence of the development of aCL in patients with early RA who received infliximab in combination with MTX, and the difference was not significant compared with patients who received placebo plus MTX.
Visvanathan
Sudha
S
Centocor, Inc., Malvern, Pennsylvania 19355, USA. svisvana@cntus.jnj.com
Wagner
Carrie
C
Smolen
Josef
J
St Clair
E William
EW
Hegedus
Ron
R
Baker
Daniel
D
Keenan
Gregory
G
D000328:Adult; D000368:Aged; D017153:Antibodies, Anticardiolipin / Q000097:blood*; D000911:Antibodies, Monoclonal / Q000009:adverse effects / Q000627:therapeutic use*; D018501:Antirheumatic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000188:drug therapy* / Q000276:immunology*; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D007075:Immunoglobulin M / Q000097:blood*; D007239:Infections / Q000453:epidemiology; D000069285:Infliximab; D008297:Male; D008727:Methotrexate / Q000009:adverse effects / Q000627:therapeutic use*; D008875:Middle Aged; D010919:Placebos
D017153:Antibodies, Anticardiolipin; D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D010919:Placebos; D000069285:Infliximab; D008727:Methotrexate