Association of a TNFSF13B (BAFF) regulatory region single nucleotide polymorphism with response to rituximab in antineutrophil cytoplasmic antibody–associated vasculitis

To the Editor: Rituximab is effective at inducing and maintaining remission in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).1,2 The wide interpatient variability in the duration of B-cell depletion and time to relapse as well as the significant relapse risk after treatment, costs, and adverse event rates necessitate improved patient stratification.3 Several biomarkers have been explored4,5 in diseases treated with rituximab; however, all require validation before they can enter clinical practice; among them, a role for candidate single nucleotide polymorphisms (SNPs) has been proposed.6 However, no SNP has so far shown a reliable association with response to treatment and no such study has been performed in AAV. Because the results suggested a recessive effect for the SNP rs3759467, we used recessive models for the analysis in the replication cohort and reanalysis of the primary cohort. Genotype rs6822844 Response at 6 mo Positive response TF TF percentage GG 15 1 6% GT 2 1 33% TT 0 0 0% Table E9Primary cohort recruitment according to country Country No. of patients Germany 53 Italy 49 Sweden 46 Denmark 41 Czech Republic 13 Spain 11 References 1 R.B. Jones, J.W. Tervaert, T. Hauser, R. Luqmani, M.D. Morgan, C.A. Peh, Rituximab versus cyclophosphamide in ANCA-associated renal vasculitis, N Engl J Med, Vol. 363, 2010, 211-220 2 L. Guillevin, C. Pagnoux, A. Karras, C. Khouatra, O. Aumaître, P. Cohen, Rituximab versus azathioprine for maintenance in ANCA-associated vasculitis, N Engl J Med, Vol. 371, 2014, 1771-1780 3 D.M. Roberts, R.B. Jones, R.M. Smith, F. Alberici, D.S. Kumaratne,...