B cell depletion therapy in systemic lupus erythematosus: long-term follow-up and predictors of response.
OBJECTIVE
To describe the long-term clinical outcome and safety profile of B cell depletion therapy (BCDT) in patients with systemic lupus erythematosus (SLE). It was also determined whether baseline parameters can predict the likelihood of disease flare.


METHODS
32 patients with refractory SLE were treated with BCDT using a combination protocol (rituximab and cyclo-phosphamide). Patients were assessed with the British Isles Lupus Assessment Group (BILAG) activity index, and baseline serology was measured. Flare was defined as a new BILAG 'A' or two new subsequent 'B's in any organ system.


RESULTS
Of the 32 patients, 12 have remained well after one cycle of BCDT (median follow-up 39 months). BCDT was followed by a decrease of median global BILAG scores from 13 to 5 at 6 months (p = 0.006). Baseline anti-extractable nuclear antigen (ENA) was the only identified independent predictor of flare post-BCDT (p = 0.034, odds ratio = 8, 95% CI 1.2 to 55) from multivariable analysis. Patients with low baseline serum C3 had a shorter time to flare post-BCDT (p = 0.008). Four serious adverse events were observed.


CONCLUSIONS
Autoantibody profiling may help identify patients who will have a more sustained response. Although the long-term safety profile of BCDT is favourable, ongoing vigilance is recommended.
Ng
Kristine P
KP
Centre for Rheumatology, University College London, London, UK.
Cambridge
Geraldine
G
Leandro
Maria J
MJ
Edwards
Jonathan C W
JC
Ehrenstein
Michael
M
Isenberg
David A
DA
D000328:Adult; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D058846:Antibodies, Monoclonal, Murine-Derived; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D001402:B-Lymphocytes / Q000276:immunology*; D015415:Biomarkers / Q000032:analysis; D003176:Complement C3 / Q000032:analysis; D003520:Cyclophosphamide / Q000627:therapeutic use*; D005260:Female; D005500:Follow-Up Studies; D006305:Health Status Indicators; D006801:Humans; D016015:Logistic Models; D008180:Lupus Erythematosus, Systemic / Q000276:immunology / Q000628:therapy*; D008212:Lymphocyte Depletion / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012306:Risk; D000069283:Rituximab; D013995:Time
D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D018501:Antirheumatic Agents; D015415:Biomarkers; D003176:Complement C3; D000069283:Rituximab; D003520:Cyclophosphamide