Treatment with infliximab plus methotrexate improves anemia in patients with rheumatoid arthritis independent of improvement in other clinical outcome measures-a pooled analysis from three large, multicenter, double-blind, randomized clinical trials.
OBJECTIVE
To evaluate the effect of antitumor necrosis factor-alpha monoclonal antibody infliximab treatment on anemia in patients with rheumatoid arthritis (RA).


METHODS
Data from patients with RA who received infliximab or placebo in the multicenter, placebo-controlled, double-blind, randomized ATTRACT, ASPIRE, and START studies were included in this post-hoc, pooled analysis. Infliximab (3 to 10 mg/kg) was administered every 4 or 8 weeks, and all patients received stable doses of methotrexate (MTX). We determined the percentage of anemic patients (baseline hemoglobin level <12 g/dL) who had an increase from baseline in hemoglobin level greater than or equal to 1 or 2 g/dL or achieved normal hemoglobin level at week 22. The association of improvement in anemia with improvement in clinical parameters was also evaluated.


RESULTS
Among patients with anemia at baseline, infliximab plus MTX treatment produced a significantly greater mean (standard deviation) increase in hemoglobin level from baseline to week 22 (0.74 [1.12], P < 0.0001) than placebo plus MTX (0.30 [0.92]). Significantly (P < 0.001) greater proportions of anemic patients treated with infliximab plus MTX had either at least a 1 g/dL (40%) or at least a 2 g/dL (12%) increase in hemoglobin level from baseline to week 22 or achieved normal hemoglobin level (43%) when compared with placebo plus MTX (19, 5, and 28%, respectively). Greater improvement in hemoglobin level among infliximab plus MTX-treated patients was consistently observed across subgroups and in patients without clinical response (American College of Rheumatology 20% response criteria) at week 22. Multiple regression analysis indicated that the effect of infliximab plus MTX on anemia was independent of improvement in disease activity.


CONCLUSIONS
Treatment with infliximab plus MTX significantly improved hemoglobin level among anemic RA patients when compared with treatment with placebo plus MTX, even after adjusting for improvement in disease activity.
Doyle
Mittie K
MK
Immunology, Clinical Research and Development, Centocor Inc., Malvern, PA 19355, USA. mdoyle1@its.jnj.com
Rahman
Mahboob U
MU
Han
Chenglong
C
Han
John
J
Giles
Jon
J
Bingham
Clifton O
CO
Bathon
Joan
J
D000740:Anemia / Q000150:complications / Q000188:drug therapy* / Q000473:pathology; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000188:drug therapy* / Q000473:pathology; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D000069285:Infliximab; D008297:Male; D008727:Methotrexate / Q000627:therapeutic use*; D015337:Multicenter Studies as Topic; D016032:Randomized Controlled Trials as Topic; D012044:Regression Analysis; D016896:Treatment Outcome
D000911:Antibodies, Monoclonal; D018501:Antirheumatic Agents; D006454:Hemoglobins; D000069285:Infliximab; D008727:Methotrexate