- Email: [email protected]
Predictive factors of response to rituximab therapy in rheumatoid arthritis: What do we know today?
Autoimmunity Reviews 9 (2010) 801–803
Contents lists available at ScienceDirect
Autoimmunity Reviews j o u r n a l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / a u t r ev
Review
Predictive factors of response to rituximab therapy in rheumatoid arthritis: What do we know today? Maurizio Benucci a,⁎, Mariangela Manfredi b, Piercarlo Sarzi Puttini c, Fabiola Atzeni c a b c
Rheumatology Unit, Ospedale S.Giovanni di Dio, ASL 10, Florence, Italy Immunology and Allergology Laboratory, Ospedale S.Giovanni di Dio, ASL 10, Florence, Italy Rheumatology Unit, L. Sacco University Hospital, Milan, Italy
a r t i c l e
i n f o
Article history: Received 2 June 2010 Accepted 17 July 2010 Available online 23 July 2010 Keywords: Rituximab Predictive factors Clinical response
a b s t r a c t Interest in the role of B cells in the pathogenesis of rheumatoid arthritis (RA) has increased over recent years. Rituximab (RTX), a chimeric monoclonal antibody specific for human CD20 targeting B lymphocytes, has been used to treat RA patients, and its efficacy has been clearly demonstrated in controlled clinical trials and open-label observational studies. However, it is still not known which sub-group(s) of patients will respond to RTX therapy or whether there are any factors predicting a response. The aim of this review is to discuss the most important predictive factors that are so far known. It is known that the clinical response to RTX therapy is associated with lower interferons (IFN-γ) and B-cell activating factor (BAFF) levels, the Fcγ receptor III (FcγRIII) genotype, and the C/G-174 polymorphism of interleukin 6 (IL-6); that an initial non-response to RTX depends on circulating pre-plasma cell numbers at baseline and incomplete depletion; that synovial B cells are decreased but not eliminated by RTX therapy, and that a good clinical response correlates with more substantial synovial B depletion; and, finally, that a good clinical response correlates with rheumatoid factor positivity, but not anti-cyclic citrullinated peptide antibody positivity. © 2010 Elsevier B.V. All rights reserved.
Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 2. Predictive factors before starting therapy . . . . . . . . . . . . 3. B-cell depletion . . . . . . . . . . . . . . . . . . . . . . . . 4. Synovial B-cell depletion . . . . . . . . . . . . . . . . . . . . 5. Rheumatoid factor and anti-cyclic citrullinated peptide antibodies 6. T cell depletion and cytokines . . . . . . . . . . . . . . . . . 7. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . Take-home messages . . . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . .
1. Introduction Rituximab (RTX), a genetically engineered monoclonal antibody targeting CD20+ B cells, has been shown to be effective in the treatment of rheumatoid arthritis (RA) [1–3]. The exact mechanism of
⁎ Corresponding author. Rheumatology Unit, Azienda Sanitaria di Firenze, Nuovo Ospedale S. Giovanni di Dio, Via Torregalli 3, 50143 Firenze, Italy. Tel.: + 39 0 55 7192331; fax: + 39 0 55 7192306. E-mail addresses: [email protected], [email protected] (M. Benucci). 1568-9972/$ – see front matter © 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.autrev.2010.07.006
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. 801 . 802 . 802 . 802 . 802 . 802 . 803 . 803 . . 803 .
RTX function is not known, but the drug binds CD20, a 297-amino acid phosphoprotein (33–37 kDa) found on the surface of B cells, downmodulates CD20 expression, and internalises or sheds CD20 from cell membranes. It has been suggested that selective peripheral B cell depletion may be triggered by three mechanisms: complementdependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC), and apoptosis [4]. RTX was approved in patients with RA that did not respond to first-line anti-TNFα treatment [5]. Other agents targeting B-cell depletion (e.g. ocrelizumab, and ofatumumab) are in various stages of development in the treatment of RA [6]. Still open questions concerning RTX therapy in RA are which sub-group(s)
802
M. Benucci et al. / Autoimmunity Reviews 9 (2010) 801–803
of patients will respond and whether there are any factors predicting response. 2. Predictive factors before starting therapy Recently reported predictors of a better response to RTX therapy include lower levels of type I interferons (IFN-γ) [7], lower serum levels of B-cell activating factor (BAFF) or B lymphocyte stimulator (BLyS) [8] and a favourable Fcγ receptor III (FcγRIII) genotype [9]. The same group has also indicated the possible role of polymorphism of C/ G-174 of interleukin 6 (IL-6) in poorer clinical responses on the basis of European League Against Rheumatism (EULAR) and American College of Rheumatology (ACR criteria) [10]. 3. B-cell depletion B-cell depletion has been analysed in a double-blind phase IIa clinical trial, which showed that it had no relationship with clinical response, that the recovery of peripheral B cells was variable, and that there was no relationship with the resumption of disease activity in the patients who responded to RTX [11]. B-cell numbers were measured by means of highly sensitive flow cytometry before and after each infusion, and then every three months, with a reduction to less than 0.0001 × 109/L being defined as complete depletion (as against the conventional cytometry figure of 0.05 × 109/L). Clinical responses were measured using the EULAR criteria, and the absence of complete depletion after the first infusion was associated with a poorer outcome [12]. Depletion occurred about 15 days after infusion. Repopulation occurred a mean eight months after treatment, and was due to the formation of naive B cells with increased CD38 and CD5 expressions; during the course of repopulation, there was an increase in the number of immature B cells (CD19−, IgD−, CD38high, CD10low, and CD24high). The patients who experienced a relapse of RA tended to show repopulation with higher numbers of memory B cells [13]. Another study has found that B cell repopulation predominantly involves naive CD27−IgD+ cells, and that the small number of CD27+IgD− classswitched memory B cells in the blood correlates with a good clinical response [14]. Peripheral blood (PB) and bone marrow (BM) showed a prevalence of immature and/or transitional B cells (CD38++CD24++) and CD27+IgD− memory cells, whereas IgD+ cells were completely depleted. At the time of long-term follow-up, a reduction in the number of CD27+ B cells was observed in both PB and BM; however, as this did not prevent autoantibody production, it seems that the mechanisms regulating the formation of autoreactive clones are not disrupted by RTX [15]. It has also been found that RTX therapy preferentially depletes activated CD19+HLA−DR+ B cells in the PB and BM of patients with active RA patients; a clinical response was associated with the depletion of PB and BM CD19+CD27+ memory B cells [16]. The early reconstitution phase was characterised by immature CD38++, IgD+, CD10+ B cells [17], but the use of single B cell sorting followed by nested polymerase chain reaction and Ig VH3 sequencing showed that IgD+CD27 memory B cells were particularly susceptible to the effects of RTX as there was a delay in the acquisition of Ig receptor mutations [18]. A recent paper showed that BAFF-R expression was significantly reduced on both naive and memory B cells in patients at relapse, regardless of the relationship with B-cell repopulation or serum BAFF levels. Re-establishment of active disease was also associated with an increase in class-switch recombination [19]. Blood and bone marrow from 35 RA patients were analysed for Epstein Barr virus (EBV) and parvovirus genomes. The presence of EBV genome was associated with a better clinical response to RTX. Thus, presence of EBV genome may predict clinical response to RTX [20]. A recent study of 158 patients evaluated the level of pre-plasma cells, and memory and naïve B cells at baseline and after a cycle of RTX. The initial non-responders to RTX had higher circulating pre-
plasma cell counts at baseline and showed incomplete depletion but an additional cycle of RTX before full repopulation enhanced depletion and improved clinical responses, as evaluated by means of tender and swollen joint counts, global assessment and the level of circulating C-reactive protein (CRP) [21]. Although anti-CD20 is usually effective in depleting B cells from PB, their depletion from other sites such as lymph nodes or tertiary lymphoid tissues may vary widely, and any failure to deplete B cells from these sites may lead to a non-response or early relapse. 4. Synovial B-cell depletion Studies of synovial membrane have shown that synovial B cells are depleted but not eliminated by RTX therapy [22]; in these studies, good clinical responses correlated with more substantial synovial depletion of particularly CD22 cells [22,23]. The baseline number of CD22, CD68+ macrophages and CD138+ plasma cells does not correlate with clinical response, but changes in CD68+ macrophages of the sub-lining infiltrate and synovial CD138+ plasma cells predict a clinical response [24]. No correlations have been found between clinical response and the serum levels of RTX, the development of anti-chimeric antibodies or the persistence of synovial B cells [25]. 5. Rheumatoid factor and anti-cyclic citrullinated peptide antibodies Two pre-registration studies found that rheumatoid factor(RF)positive patients showed a better response than RF-negative patients, with ACR20 response values of respectively 54% vs 41% [2] and 54% vs 48% [3], although another study found no difference between the two sub-groups [1]. Furthermore, one study has found that baseline positivity for circulating anti-cyclic citrullinated peptide (CCP) antibodies, particularly immunoglobulin M (IgM), and high levels of infiltrating CD20+ and CD79a+CD20− B cells in the rheumatoid synovium predict an incomplete response after B cell depletion [26]. A reduction in the levels of circulating RF and CCP antibodies was detected in one study [24], and others have found different concentrations of synovial RF-IgM and CCP-IgG antibodies, with high levels in patients with lymphoid aggregates; RTX significantly reduced the total IgM and IgG synovial/serum index (SSI) and both IgM and IgG1 messenger RNA (mRNA) in the aggregate-containing tissues but, surprisingly, the RF-IgM and anti-CCP-IgG SSIs remained unchanged in aggregate-containing synovia [27]. A reduction in BM secreting IgM and IgD has been observed for three months after the administration of one cycle of RTX, but reductions in IgG and IgA were found in the long term [15]. A large-scale Italian study of 110 patients found that the variables associated with an ACR 50 response were a lower health assessment questionnaire (HAQ) score, fewer failures on previous anti-tumour necrosis factor (TNF) agents before RTX, and RF (but not anti-CCP) positivity, whereas only RF positivity correlated with a EULAR moderate to good response in both the univariate and the multivariate analysis [28]. 6. T cell depletion and cytokines The reduction in the expression of CD20 is not restricted to B lymphocytes because a small population (about 1.6–2.4%) of all T cells coexpresses CD20 (CD20+ T cells) [29]. The phenotype and apoptosis of peripheral blood mononuclear cells (PBMCs) taken from healthy donors and RA patients were examined by means of 4-colour fluorescenceactivated cell sorting analysis, and cytokine production was determined by means of intracellular staining and the measurement of cytokines in the supernatants. RTX therapy eliminated the CD20+ T and B cells from the peripheral blood of the RA patients, and polyclonal CD3+CD20+ cells were functionally characterised by constitutive cytokine production
M. Benucci et al. / Autoimmunity Reviews 9 (2010) 801–803
(interleukin-1 and TNF). These findings suggest that CD20+ T cells are a terminally differentiated cell type with immunoregulatory and proinflammatory properties. The depletion of CD20+ T cells may therefore be an additional mechanism by which anti-CD20 therapy works in patients with RA [30]. Intracellular staining of cytokines in PBMCs before and after RTX administration has shown that the cytokine production representative of helper T cells (Th1-, Th2- and Th17-type responses) decreases abruptly after treatment [31]. The chemokine (C–C motif) receptor CCR5 and its ligand CCL5 play key roles in the intra-articular recruitment of PBMCs in RA patients [32], and surface CCR5 density determines the level of chemotaxis of a T cell towards RA synovial cells producing CCL5 [33]. A recent quantitative cell flow analysis followed T4 cell surface CCR5 density in 27 subjects with RA before and after treatment with RTX and found low T4 cell surface CCR5 densities before treatment that positively correlated with disease activity as measured by the 28-joint disease activity score, and negatively correlated with CCL5 mRNA concentrations in PBMCs; after treatment, there was a high proportion of intracellular CCR5 molecules, a pattern that compatible with ligandinduced CCR5 internalisation [34]. 7. Conclusions The described findings suggest that a failure to deplete pathogenic B cells adequately in tissue sites is an important predictor of an incomplete response to B cell depletion therapy. A higher fraction of memory B cells and a lower fraction of immature transitional B cells during reconstitution correlate with earlier disease relapse, thus suggesting that the outcome of B depletion depends on the T helper balance between the protective and pathogenic B cell populations. Take-home messages • A number of predictive factors are associated with a clinical response to rituximab therapy, including lower levels of IFN-γ and BAFF, the FcγRIII genotype and the C/G-174 polymorphism of IL-6. • An initial non-response to RTX depends on circulating pre-plasma cell numbers at baseline and incomplete depletion. • A good clinical response correlates with more substantial synovial B cell depletion and RF (but not anti-CCP) positivity.
References [1] Edwards JC, Szczepanski L, Szechinski J, Filipowicz-Sosnowska A, Emery P, Close DR, et al. Efficacy of B-cell-targeted therapy with rituximab in patients with rheumatoid arthritis. N Engl J Med 2004;350:2572–81. [2] Cohen SB, Emery P, Greenwald MW, Dougados M, Furie RA, Genovese MC, et al. Rituximab for rheumatoid arthritis refractory to anti-tumor necrosis factor therapy: results of a multicenter, randomized, double-blind, placebo-controlled, phase III trial evaluating primary efficacy and safety at twenty-four weeks. Arthritis Rheum 2006;54:2793–806. [3] Caporali R, Caprioli M, Bobbio-Pallavicini F, Bugatti S, Montecucco C. Long term treatment of rheumatoid arthritis with rituximab. Autoimmun Rev 2009;8:591–4. [4] Atzeni F, Doria A, Maurizio T, Sarzi-Puttini P. What is the role of rituximab in the treatment of rheumatoid arthritis? Autoimmun Rev 2007;6:553–8. [5] Papagoras C, Voulgari PV, Drosos AA. Strategies after failure of the first anti-tumor necrosis factor α agent in rheumatoid arthritis. Autoimmun Rev 2010;9:574–82. [6] Senolt L, Vencovsky J, Pavelka K, Ospelt C, Gay S. Prospective new biological therapies for rheumatoid arthritis. Autoimmun Rev 2009;2:102–7. [7] Thurlings R, Boumans MJH, Tekstra J. The type I IFN signature is a negative predictor of clinical response to rituximab treatment in RA. Arthritis Rheum 2009;60:S626–7. [8] Fabris M, Quartuccio L, Saracco M, Pellerito R, Atzeni F, Sarzi-Puttini P, et al. BLyS promoter polymorphism and response to rituximab in rheumatoid arthritis patients positive or negative for the rheumatoid factor. Arthritis Rheum 2009;60: S627.
803
[9] Quartuccio L, Lombardi S, Fabris M. Long term effects of rituximab in rheumatoid arthritis: clinical, biologic and pharmacogenetic aspects. Ann N Y Acad Sci 2009;1173:692–700. [10] Fabris M, Quartuccio, Lombardi S, Saracco M, Atzeni F, Carletto A, et al. The role of the IL-6 promoter polymorphism in predicting rituximab efficacy in rheumatoid arthritis. Ann Rheum Dis 2010;69(S3):671. [11] Breedveld F, Agarwal S, Yin M, Ren S, Li NF, Shaw TM, et al. Rituximab pharmacokinetics in patients with rheumatoid arthritis: B cells levels do not correlate with clinical response. J Clin Pharmacol 2007;47:1119–28. [12] Dass S, Rawstron AC, Vital EM, Henshaw K, McGonagle D, Emery P. Highly sensitive B cell analysis predicts response to rituximab therapy in rheumatoid arthritis. Arthritis Rheum 2008;58:2993–9. [13] Leandro MJ, Cambridge G, Ehrestein RM, Edwards JC. Reconstitution of peripheral blood B cells, after depletion with rituximab in patients with rheumatoid arthritis. Arthritis Rheum 2006;54:612–20. [14] Möller B, Aeberli D, Eggli S, Fuhrer M, Vajtai I, Vögelin E, et al. Class-switched B cells display response to therapeutic B-cell depletion in rheumatoid arthritis. Arthritis Rhes Ther 2009;11:R62. [15] Rehnberg M, Amu S, Tarkowski A, Bokarewa MI, Brisslert M. Short- and long-term effects of anti-CD20 treatment on B cell ontogeny in bone marrow of patients with rheumatoid arthritis. Arthritis Rhes Ther 2009;11:R123. [16] Nakou M, Katsikas G, Sidiropoulos P, Bertsias G, Papadimitraki E, Raptopoulou A, et al. Rituximab therapy reduces activated B cells in both the peripheral blood and bone marrow of patients with rheumatoid arthritis: depletion of memory B cells correlates with clinical response. Arthritis Rhes Ther 2009;11:R121. [17] Roll P, Dorner T, Tony HP. Anti CD20 therapy in patients with rheumatoid arthritis : predictor of response and B cells subset regeneration after repeated treatment. Arthritis Rheum 2008;58:1566–75. [18] Muhammad K, Roll P, Heinsele H, Dorner T, Tony HP. Delayed acquisition of somatic hypermutations in repopulated IgD+CD27+ memory B cell receptors after rituximab treatment. Arthritis Rheum 2009;60:228–93. [19] De la Torre Ortega I, Moura RA, Leandro MJ, Edwards JW, Cambridge G. B cells activating factor receptor expression on naive and memory B cells: relationship with relapse in patients with rheumatoid arthritis following B cells depletion therapy. Ann Rheum Dis 2010 [Epub ahead of print]. [20] Magnusson M, Brisslert M, Zendjanchi K, Lindh M, Bokarewa MI. Epstein Barr virus in bone marrow of rheumatoid arthritis patients predict response to rituximab treatment. Rheumatology(Oxford) 2010 [Epub ahead of print]. [21] Vital EM, Dass S, Rawstron AC, Buch MH, Goeb V, Henshaw K, et al. Management of non-response to rituximab in rheumatoid arthritis: predictor and outcome of retreatment. Arthritis Rheum 2010;62:1273–9. [22] Kavanaugh A, Rosengren S, Lee SJ, Hammacher D, Firestein GS, Kalunian K, et al. Assessment of rituximab's immunomodulatory synovial effects(ARISE trials) 1: clinical and synovial biomarker result. Ann Rheum Dis 2008;67:917–25. [23] Voss K, Thurlings RM, Wijbrands CA, van Schaarderburg D, Gerlag DM, Tak PP. Early effects of rituximab on the synovial cell infiltrate in patients with rheumatoid arthritis. Arthritis Rheum 2007;56:772–8. [24] Thurlings RM, Vos K, Wijbrandts CA, Zwinderman AH, Gerlang DM, Tak PP. Synovial tissue response to rituximab: mechanism of action and identification of biomarkers of response. Ann Rheum Dis 2008;67:917–25. [25] Thurlings RM, Teng O, Vos K. Clinical response, pharmacokinetics, development of human anti-chimaeric antibodies, and synovial tissue response to rituximab treatment in patients with rheumatoid arthritis. Ann Rheum Dis 2010;69:409–12. [26] Teng YK, Levarht EW, Hashemi M, Bajema IM, Toes RF, Huizinga TW, et al. Immunohistochemical analysis as a means to predict responsiveness to rituximab treatment. Arthritis Rheum 2008;58:3657–64. [27] Rosengren S, Wei N, Kalunian Kenneth C, KC Nathan J, Zvaifler N, Arthur Kavanaugh A, et al. Elevated autoantibody content in rheumatoid arthritis synovia with lymphoid aggregates and the effect of rituximab. Arthritis Res Ther 2008;10: R105. [28] Quartuccio L, Fabris M, Salvin S, Atzeni F, Saracco M, Benucci M, et al. Rheumatoid factor positivity rather than anti-CCP positivity, a lower disability and a lower number of anti-TNF agents failed are associated with response to rituximab in rheumatoid arthritis. Rheumatology (Oxford) 2009;12:1557–9. [29] Hultin LE, Hausner MA, Hultin PM, Giorgi JV. CD20 (pan-B cell) antigen is expressed at a low level on a subpopulation of human T lymphocytes. Cytometry 1993;14:196–204. [30] Wilk E, Witte T, Marquardt N, Horvath T, Kalippke K, Scholz K, et al. Depletion of functionally active CD20+ T cells by rituximab treatment. Arthritis Rheum 2009;60:3563–71. [31] Yamamoto A, Sato K, Miyoshi F, Shindo F, Yoshida Y, Yokota K, et al. Analysis of cytokine production patterns of peripheral blood mononuclear cells from a rheumatoid arthritis patient successfully treated with rituximab. Mod Rheumatol 2010;2:183–7. [32] Patel DD, Zachariah JP, Whichard LP. CXCR3 and CCR5 ligands in rheumatoid arthritis synovium. Clin Immunol 2001;98:39–45. [33] Desmetz C, Lin Y-L, Mettling C, Portales P, Noël D, Clot J, et al. Cell surface CCR5 density determines the intensity of T cell migration towards rheumatoid arthritis synoviocytes. Clin Immunol 2007;123:148–54. [34] Pierre Portale P, Fabre S, Vincent T, Desmetz C, Reant B, Noel D, et al. Peripheral blood T4 cell surface CCR5 density as a marker of activity in rheumatoid arthritis treated with anti-CD20 monoclonal antibody. Immunology 2009;128:738–45.
Contents lists available at ScienceDirect
Autoimmunity Reviews j o u r n a l h o m e p a g e : w w w. e l s ev i e r. c o m / l o c a t e / a u t r ev
Review
Predictive factors of response to rituximab therapy in rheumatoid arthritis: What do we know today? Maurizio Benucci a,⁎, Mariangela Manfredi b, Piercarlo Sarzi Puttini c, Fabiola Atzeni c a b c
Rheumatology Unit, Ospedale S.Giovanni di Dio, ASL 10, Florence, Italy Immunology and Allergology Laboratory, Ospedale S.Giovanni di Dio, ASL 10, Florence, Italy Rheumatology Unit, L. Sacco University Hospital, Milan, Italy
a r t i c l e
i n f o
Article history: Received 2 June 2010 Accepted 17 July 2010 Available online 23 July 2010 Keywords: Rituximab Predictive factors Clinical response
a b s t r a c t Interest in the role of B cells in the pathogenesis of rheumatoid arthritis (RA) has increased over recent years. Rituximab (RTX), a chimeric monoclonal antibody specific for human CD20 targeting B lymphocytes, has been used to treat RA patients, and its efficacy has been clearly demonstrated in controlled clinical trials and open-label observational studies. However, it is still not known which sub-group(s) of patients will respond to RTX therapy or whether there are any factors predicting a response. The aim of this review is to discuss the most important predictive factors that are so far known. It is known that the clinical response to RTX therapy is associated with lower interferons (IFN-γ) and B-cell activating factor (BAFF) levels, the Fcγ receptor III (FcγRIII) genotype, and the C/G-174 polymorphism of interleukin 6 (IL-6); that an initial non-response to RTX depends on circulating pre-plasma cell numbers at baseline and incomplete depletion; that synovial B cells are decreased but not eliminated by RTX therapy, and that a good clinical response correlates with more substantial synovial B depletion; and, finally, that a good clinical response correlates with rheumatoid factor positivity, but not anti-cyclic citrullinated peptide antibody positivity. © 2010 Elsevier B.V. All rights reserved.
Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 2. Predictive factors before starting therapy . . . . . . . . . . . . 3. B-cell depletion . . . . . . . . . . . . . . . . . . . . . . . . 4. Synovial B-cell depletion . . . . . . . . . . . . . . . . . . . . 5. Rheumatoid factor and anti-cyclic citrullinated peptide antibodies 6. T cell depletion and cytokines . . . . . . . . . . . . . . . . . 7. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . Take-home messages . . . . . . . . . . . . . . . . . . . . . . . . References . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . .
1. Introduction Rituximab (RTX), a genetically engineered monoclonal antibody targeting CD20+ B cells, has been shown to be effective in the treatment of rheumatoid arthritis (RA) [1–3]. The exact mechanism of
⁎ Corresponding author. Rheumatology Unit, Azienda Sanitaria di Firenze, Nuovo Ospedale S. Giovanni di Dio, Via Torregalli 3, 50143 Firenze, Italy. Tel.: + 39 0 55 7192331; fax: + 39 0 55 7192306. E-mail addresses: [email protected], [email protected] (M. Benucci). 1568-9972/$ – see front matter © 2010 Elsevier B.V. All rights reserved. doi:10.1016/j.autrev.2010.07.006
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. . . . . . . . .
. 801 . 802 . 802 . 802 . 802 . 802 . 803 . 803 . . 803 .
RTX function is not known, but the drug binds CD20, a 297-amino acid phosphoprotein (33–37 kDa) found on the surface of B cells, downmodulates CD20 expression, and internalises or sheds CD20 from cell membranes. It has been suggested that selective peripheral B cell depletion may be triggered by three mechanisms: complementdependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC), and apoptosis [4]. RTX was approved in patients with RA that did not respond to first-line anti-TNFα treatment [5]. Other agents targeting B-cell depletion (e.g. ocrelizumab, and ofatumumab) are in various stages of development in the treatment of RA [6]. Still open questions concerning RTX therapy in RA are which sub-group(s)
802
M. Benucci et al. / Autoimmunity Reviews 9 (2010) 801–803
of patients will respond and whether there are any factors predicting response. 2. Predictive factors before starting therapy Recently reported predictors of a better response to RTX therapy include lower levels of type I interferons (IFN-γ) [7], lower serum levels of B-cell activating factor (BAFF) or B lymphocyte stimulator (BLyS) [8] and a favourable Fcγ receptor III (FcγRIII) genotype [9]. The same group has also indicated the possible role of polymorphism of C/ G-174 of interleukin 6 (IL-6) in poorer clinical responses on the basis of European League Against Rheumatism (EULAR) and American College of Rheumatology (ACR criteria) [10]. 3. B-cell depletion B-cell depletion has been analysed in a double-blind phase IIa clinical trial, which showed that it had no relationship with clinical response, that the recovery of peripheral B cells was variable, and that there was no relationship with the resumption of disease activity in the patients who responded to RTX [11]. B-cell numbers were measured by means of highly sensitive flow cytometry before and after each infusion, and then every three months, with a reduction to less than 0.0001 × 109/L being defined as complete depletion (as against the conventional cytometry figure of 0.05 × 109/L). Clinical responses were measured using the EULAR criteria, and the absence of complete depletion after the first infusion was associated with a poorer outcome [12]. Depletion occurred about 15 days after infusion. Repopulation occurred a mean eight months after treatment, and was due to the formation of naive B cells with increased CD38 and CD5 expressions; during the course of repopulation, there was an increase in the number of immature B cells (CD19−, IgD−, CD38high, CD10low, and CD24high). The patients who experienced a relapse of RA tended to show repopulation with higher numbers of memory B cells [13]. Another study has found that B cell repopulation predominantly involves naive CD27−IgD+ cells, and that the small number of CD27+IgD− classswitched memory B cells in the blood correlates with a good clinical response [14]. Peripheral blood (PB) and bone marrow (BM) showed a prevalence of immature and/or transitional B cells (CD38++CD24++) and CD27+IgD− memory cells, whereas IgD+ cells were completely depleted. At the time of long-term follow-up, a reduction in the number of CD27+ B cells was observed in both PB and BM; however, as this did not prevent autoantibody production, it seems that the mechanisms regulating the formation of autoreactive clones are not disrupted by RTX [15]. It has also been found that RTX therapy preferentially depletes activated CD19+HLA−DR+ B cells in the PB and BM of patients with active RA patients; a clinical response was associated with the depletion of PB and BM CD19+CD27+ memory B cells [16]. The early reconstitution phase was characterised by immature CD38++, IgD+, CD10+ B cells [17], but the use of single B cell sorting followed by nested polymerase chain reaction and Ig VH3 sequencing showed that IgD+CD27 memory B cells were particularly susceptible to the effects of RTX as there was a delay in the acquisition of Ig receptor mutations [18]. A recent paper showed that BAFF-R expression was significantly reduced on both naive and memory B cells in patients at relapse, regardless of the relationship with B-cell repopulation or serum BAFF levels. Re-establishment of active disease was also associated with an increase in class-switch recombination [19]. Blood and bone marrow from 35 RA patients were analysed for Epstein Barr virus (EBV) and parvovirus genomes. The presence of EBV genome was associated with a better clinical response to RTX. Thus, presence of EBV genome may predict clinical response to RTX [20]. A recent study of 158 patients evaluated the level of pre-plasma cells, and memory and naïve B cells at baseline and after a cycle of RTX. The initial non-responders to RTX had higher circulating pre-
plasma cell counts at baseline and showed incomplete depletion but an additional cycle of RTX before full repopulation enhanced depletion and improved clinical responses, as evaluated by means of tender and swollen joint counts, global assessment and the level of circulating C-reactive protein (CRP) [21]. Although anti-CD20 is usually effective in depleting B cells from PB, their depletion from other sites such as lymph nodes or tertiary lymphoid tissues may vary widely, and any failure to deplete B cells from these sites may lead to a non-response or early relapse. 4. Synovial B-cell depletion Studies of synovial membrane have shown that synovial B cells are depleted but not eliminated by RTX therapy [22]; in these studies, good clinical responses correlated with more substantial synovial depletion of particularly CD22 cells [22,23]. The baseline number of CD22, CD68+ macrophages and CD138+ plasma cells does not correlate with clinical response, but changes in CD68+ macrophages of the sub-lining infiltrate and synovial CD138+ plasma cells predict a clinical response [24]. No correlations have been found between clinical response and the serum levels of RTX, the development of anti-chimeric antibodies or the persistence of synovial B cells [25]. 5. Rheumatoid factor and anti-cyclic citrullinated peptide antibodies Two pre-registration studies found that rheumatoid factor(RF)positive patients showed a better response than RF-negative patients, with ACR20 response values of respectively 54% vs 41% [2] and 54% vs 48% [3], although another study found no difference between the two sub-groups [1]. Furthermore, one study has found that baseline positivity for circulating anti-cyclic citrullinated peptide (CCP) antibodies, particularly immunoglobulin M (IgM), and high levels of infiltrating CD20+ and CD79a+CD20− B cells in the rheumatoid synovium predict an incomplete response after B cell depletion [26]. A reduction in the levels of circulating RF and CCP antibodies was detected in one study [24], and others have found different concentrations of synovial RF-IgM and CCP-IgG antibodies, with high levels in patients with lymphoid aggregates; RTX significantly reduced the total IgM and IgG synovial/serum index (SSI) and both IgM and IgG1 messenger RNA (mRNA) in the aggregate-containing tissues but, surprisingly, the RF-IgM and anti-CCP-IgG SSIs remained unchanged in aggregate-containing synovia [27]. A reduction in BM secreting IgM and IgD has been observed for three months after the administration of one cycle of RTX, but reductions in IgG and IgA were found in the long term [15]. A large-scale Italian study of 110 patients found that the variables associated with an ACR 50 response were a lower health assessment questionnaire (HAQ) score, fewer failures on previous anti-tumour necrosis factor (TNF) agents before RTX, and RF (but not anti-CCP) positivity, whereas only RF positivity correlated with a EULAR moderate to good response in both the univariate and the multivariate analysis [28]. 6. T cell depletion and cytokines The reduction in the expression of CD20 is not restricted to B lymphocytes because a small population (about 1.6–2.4%) of all T cells coexpresses CD20 (CD20+ T cells) [29]. The phenotype and apoptosis of peripheral blood mononuclear cells (PBMCs) taken from healthy donors and RA patients were examined by means of 4-colour fluorescenceactivated cell sorting analysis, and cytokine production was determined by means of intracellular staining and the measurement of cytokines in the supernatants. RTX therapy eliminated the CD20+ T and B cells from the peripheral blood of the RA patients, and polyclonal CD3+CD20+ cells were functionally characterised by constitutive cytokine production
M. Benucci et al. / Autoimmunity Reviews 9 (2010) 801–803
(interleukin-1 and TNF). These findings suggest that CD20+ T cells are a terminally differentiated cell type with immunoregulatory and proinflammatory properties. The depletion of CD20+ T cells may therefore be an additional mechanism by which anti-CD20 therapy works in patients with RA [30]. Intracellular staining of cytokines in PBMCs before and after RTX administration has shown that the cytokine production representative of helper T cells (Th1-, Th2- and Th17-type responses) decreases abruptly after treatment [31]. The chemokine (C–C motif) receptor CCR5 and its ligand CCL5 play key roles in the intra-articular recruitment of PBMCs in RA patients [32], and surface CCR5 density determines the level of chemotaxis of a T cell towards RA synovial cells producing CCL5 [33]. A recent quantitative cell flow analysis followed T4 cell surface CCR5 density in 27 subjects with RA before and after treatment with RTX and found low T4 cell surface CCR5 densities before treatment that positively correlated with disease activity as measured by the 28-joint disease activity score, and negatively correlated with CCL5 mRNA concentrations in PBMCs; after treatment, there was a high proportion of intracellular CCR5 molecules, a pattern that compatible with ligandinduced CCR5 internalisation [34]. 7. Conclusions The described findings suggest that a failure to deplete pathogenic B cells adequately in tissue sites is an important predictor of an incomplete response to B cell depletion therapy. A higher fraction of memory B cells and a lower fraction of immature transitional B cells during reconstitution correlate with earlier disease relapse, thus suggesting that the outcome of B depletion depends on the T helper balance between the protective and pathogenic B cell populations. Take-home messages • A number of predictive factors are associated with a clinical response to rituximab therapy, including lower levels of IFN-γ and BAFF, the FcγRIII genotype and the C/G-174 polymorphism of IL-6. • An initial non-response to RTX depends on circulating pre-plasma cell numbers at baseline and incomplete depletion. • A good clinical response correlates with more substantial synovial B cell depletion and RF (but not anti-CCP) positivity.
References [1] Edwards JC, Szczepanski L, Szechinski J, Filipowicz-Sosnowska A, Emery P, Close DR, et al. Efficacy of B-cell-targeted therapy with rituximab in patients with rheumatoid arthritis. N Engl J Med 2004;350:2572–81. [2] Cohen SB, Emery P, Greenwald MW, Dougados M, Furie RA, Genovese MC, et al. Rituximab for rheumatoid arthritis refractory to anti-tumor necrosis factor therapy: results of a multicenter, randomized, double-blind, placebo-controlled, phase III trial evaluating primary efficacy and safety at twenty-four weeks. Arthritis Rheum 2006;54:2793–806. [3] Caporali R, Caprioli M, Bobbio-Pallavicini F, Bugatti S, Montecucco C. Long term treatment of rheumatoid arthritis with rituximab. Autoimmun Rev 2009;8:591–4. [4] Atzeni F, Doria A, Maurizio T, Sarzi-Puttini P. What is the role of rituximab in the treatment of rheumatoid arthritis? Autoimmun Rev 2007;6:553–8. [5] Papagoras C, Voulgari PV, Drosos AA. Strategies after failure of the first anti-tumor necrosis factor α agent in rheumatoid arthritis. Autoimmun Rev 2010;9:574–82. [6] Senolt L, Vencovsky J, Pavelka K, Ospelt C, Gay S. Prospective new biological therapies for rheumatoid arthritis. Autoimmun Rev 2009;2:102–7. [7] Thurlings R, Boumans MJH, Tekstra J. The type I IFN signature is a negative predictor of clinical response to rituximab treatment in RA. Arthritis Rheum 2009;60:S626–7. [8] Fabris M, Quartuccio L, Saracco M, Pellerito R, Atzeni F, Sarzi-Puttini P, et al. BLyS promoter polymorphism and response to rituximab in rheumatoid arthritis patients positive or negative for the rheumatoid factor. Arthritis Rheum 2009;60: S627.
803
[9] Quartuccio L, Lombardi S, Fabris M. Long term effects of rituximab in rheumatoid arthritis: clinical, biologic and pharmacogenetic aspects. Ann N Y Acad Sci 2009;1173:692–700. [10] Fabris M, Quartuccio, Lombardi S, Saracco M, Atzeni F, Carletto A, et al. The role of the IL-6 promoter polymorphism in predicting rituximab efficacy in rheumatoid arthritis. Ann Rheum Dis 2010;69(S3):671. [11] Breedveld F, Agarwal S, Yin M, Ren S, Li NF, Shaw TM, et al. Rituximab pharmacokinetics in patients with rheumatoid arthritis: B cells levels do not correlate with clinical response. J Clin Pharmacol 2007;47:1119–28. [12] Dass S, Rawstron AC, Vital EM, Henshaw K, McGonagle D, Emery P. Highly sensitive B cell analysis predicts response to rituximab therapy in rheumatoid arthritis. Arthritis Rheum 2008;58:2993–9. [13] Leandro MJ, Cambridge G, Ehrestein RM, Edwards JC. Reconstitution of peripheral blood B cells, after depletion with rituximab in patients with rheumatoid arthritis. Arthritis Rheum 2006;54:612–20. [14] Möller B, Aeberli D, Eggli S, Fuhrer M, Vajtai I, Vögelin E, et al. Class-switched B cells display response to therapeutic B-cell depletion in rheumatoid arthritis. Arthritis Rhes Ther 2009;11:R62. [15] Rehnberg M, Amu S, Tarkowski A, Bokarewa MI, Brisslert M. Short- and long-term effects of anti-CD20 treatment on B cell ontogeny in bone marrow of patients with rheumatoid arthritis. Arthritis Rhes Ther 2009;11:R123. [16] Nakou M, Katsikas G, Sidiropoulos P, Bertsias G, Papadimitraki E, Raptopoulou A, et al. Rituximab therapy reduces activated B cells in both the peripheral blood and bone marrow of patients with rheumatoid arthritis: depletion of memory B cells correlates with clinical response. Arthritis Rhes Ther 2009;11:R121. [17] Roll P, Dorner T, Tony HP. Anti CD20 therapy in patients with rheumatoid arthritis : predictor of response and B cells subset regeneration after repeated treatment. Arthritis Rheum 2008;58:1566–75. [18] Muhammad K, Roll P, Heinsele H, Dorner T, Tony HP. Delayed acquisition of somatic hypermutations in repopulated IgD+CD27+ memory B cell receptors after rituximab treatment. Arthritis Rheum 2009;60:228–93. [19] De la Torre Ortega I, Moura RA, Leandro MJ, Edwards JW, Cambridge G. B cells activating factor receptor expression on naive and memory B cells: relationship with relapse in patients with rheumatoid arthritis following B cells depletion therapy. Ann Rheum Dis 2010 [Epub ahead of print]. [20] Magnusson M, Brisslert M, Zendjanchi K, Lindh M, Bokarewa MI. Epstein Barr virus in bone marrow of rheumatoid arthritis patients predict response to rituximab treatment. Rheumatology(Oxford) 2010 [Epub ahead of print]. [21] Vital EM, Dass S, Rawstron AC, Buch MH, Goeb V, Henshaw K, et al. Management of non-response to rituximab in rheumatoid arthritis: predictor and outcome of retreatment. Arthritis Rheum 2010;62:1273–9. [22] Kavanaugh A, Rosengren S, Lee SJ, Hammacher D, Firestein GS, Kalunian K, et al. Assessment of rituximab's immunomodulatory synovial effects(ARISE trials) 1: clinical and synovial biomarker result. Ann Rheum Dis 2008;67:917–25. [23] Voss K, Thurlings RM, Wijbrands CA, van Schaarderburg D, Gerlag DM, Tak PP. Early effects of rituximab on the synovial cell infiltrate in patients with rheumatoid arthritis. Arthritis Rheum 2007;56:772–8. [24] Thurlings RM, Vos K, Wijbrandts CA, Zwinderman AH, Gerlang DM, Tak PP. Synovial tissue response to rituximab: mechanism of action and identification of biomarkers of response. Ann Rheum Dis 2008;67:917–25. [25] Thurlings RM, Teng O, Vos K. Clinical response, pharmacokinetics, development of human anti-chimaeric antibodies, and synovial tissue response to rituximab treatment in patients with rheumatoid arthritis. Ann Rheum Dis 2010;69:409–12. [26] Teng YK, Levarht EW, Hashemi M, Bajema IM, Toes RF, Huizinga TW, et al. Immunohistochemical analysis as a means to predict responsiveness to rituximab treatment. Arthritis Rheum 2008;58:3657–64. [27] Rosengren S, Wei N, Kalunian Kenneth C, KC Nathan J, Zvaifler N, Arthur Kavanaugh A, et al. Elevated autoantibody content in rheumatoid arthritis synovia with lymphoid aggregates and the effect of rituximab. Arthritis Res Ther 2008;10: R105. [28] Quartuccio L, Fabris M, Salvin S, Atzeni F, Saracco M, Benucci M, et al. Rheumatoid factor positivity rather than anti-CCP positivity, a lower disability and a lower number of anti-TNF agents failed are associated with response to rituximab in rheumatoid arthritis. Rheumatology (Oxford) 2009;12:1557–9. [29] Hultin LE, Hausner MA, Hultin PM, Giorgi JV. CD20 (pan-B cell) antigen is expressed at a low level on a subpopulation of human T lymphocytes. Cytometry 1993;14:196–204. [30] Wilk E, Witte T, Marquardt N, Horvath T, Kalippke K, Scholz K, et al. Depletion of functionally active CD20+ T cells by rituximab treatment. Arthritis Rheum 2009;60:3563–71. [31] Yamamoto A, Sato K, Miyoshi F, Shindo F, Yoshida Y, Yokota K, et al. Analysis of cytokine production patterns of peripheral blood mononuclear cells from a rheumatoid arthritis patient successfully treated with rituximab. Mod Rheumatol 2010;2:183–7. [32] Patel DD, Zachariah JP, Whichard LP. CXCR3 and CCR5 ligands in rheumatoid arthritis synovium. Clin Immunol 2001;98:39–45. [33] Desmetz C, Lin Y-L, Mettling C, Portales P, Noël D, Clot J, et al. Cell surface CCR5 density determines the intensity of T cell migration towards rheumatoid arthritis synoviocytes. Clin Immunol 2007;123:148–54. [34] Pierre Portale P, Fabre S, Vincent T, Desmetz C, Reant B, Noel D, et al. Peripheral blood T4 cell surface CCR5 density as a marker of activity in rheumatoid arthritis treated with anti-CD20 monoclonal antibody. Immunology 2009;128:738–45.