PT  - JOURNAL ARTICLE
AU  - Md Yuzaiful Md Yusof
AU  - Edward M Vital
AU  - Sudipto Das
AU  - Shouvik Dass
AU  - Gururaj Arumugakani
AU  - Sinisa Savic
AU  - Andrew C Rawstron
AU  - Paul Emery
TI  - Repeat cycles of rituximab on clinical relapse in ANCA-associated vasculitis: identifying B cell biomarkers for relapse to guide retreatment decisions
AID  - 10.1136/annrheumdis-2014-206496
DP  - 2015 Sep 01
TA  - Annals of the Rheumatic Diseases
PG  - 1734--1738
VI  - 74
IP  - 9
4099  - http://ard.bmj.com/content/74/9/1734.short
4100  - http://ard.bmj.com/content/74/9/1734.full
SO  - Ann Rheum Dis2015 Sep 01; 74
AB  - Objective To assess clinical and B cell biomarkers to predict relapse after rituximab in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) using retreatment on clinical relapse strategy.Methods 35 patients with AAV received treatment with 2×1000 mg rituximab, repeated on clinical relapse (up to 5 cycles). Disease activity was assessed by Birmingham Vasculitis Activity Score (BVAS) and peripheral B cell subsets using highly sensitive flow cytometry (HSFC) as previously described; both performed at baseline and every 3 months.Results Response rates were high: >83%, with median time-to-relapse of 82 weeks for cycle 1 (C1) and >54 weeks for all cycles. Prior to rituximab, AAV was characterised by naïve B-lymphopenia compared to healthy controls. This dysregulation was more marked in patients with raised C-reactive protein (CRP) (p<0.05). In C1, no clinical feature predicted relapse. However, repopulation of naïve B cell at 6 months was associated with a reduced risk of relapse (HR: 0.326, 95% 0.114 to 0.930, p=0.036). Relapse rates at 12 and 18 months were 0% and 14% with naïve repopulation at 6 months, and 31% and 54% without naïve repopulation.Conclusions Responses to B cell depletion therapy are long-lasting and relapse post-treatment may be predicted by absence of naïve B cell repopulation at 6 months. Naïve B-lymphopenia may be a biomarker of disease activity in AAV.