Rituximab as maintenance therapy for ANCA-associated vasculitides: pooled analysis and long-term outcome of 277 patients included in the MAINRITSAN trials.

OBJECTIVE: To compare the long-term efficacy and safety of azathioprine (AZA), 18-month fixed-schedule rituximab (RTX), 18-month tailored RTX and 36-month RTX in preventing relapses in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis who achieved a complete remission after induction therapy. Patients treated with 36-month RTX received either a fixed or a tailored regimen for the first 18 months and a fixed regimen for the last 18 months (36-month fixed/fixed RTX and 36-month tailored/fixed RTX, respectively). METHODS: The Maintenance of Remission using Rituximab in Systemic ANCA-associated Vasculitis (MAINRITSAN) trials sequentially compared: 18-month fixed-schedule RTX versus AZA (MAINRITSAN); 18-month fixed-schedule RTX versus 18-month tailored-RTX (MAINRITSAN2); and extended therapy to 36 months with four additional RTX infusions after MAINRITSAN2 versus placebo (MAINRITSAN3). Patients were then followed prospectively through month 84 and their data were pooled to analyse relapses and adverse events. The primary endpoint was relapse-free survival at month 84. RESULTS: 277 patients were enrolled and divided in 5 groups: AZA (n=58), 18-month fixed-schedule RTX (n=97), 18-month tailored-RTX (n=40), 36-month tailored/fixed RTX (n=42), 36-month fixed/fixed RTX (n=41). After adjustment for prognostic factors, 18-month fixed-schedule RTX was superior to AZA in preventing major relapses at month 84 (HR 0.38, 95% CI 0.20 to 0.71). The 18-month tailored-RTX regimen was associated with an increased risk of major relapse compared with fixed-schedule regimen (HR 2.92, 95% CI 1.43 to 5.96). The risk of major relapse was similar between 36-month fixed/fixed and 18-month fixed-RTX (HR 0.69, 95% CI 0.38 to 1.25). CONCLUSIONS: According to these results, it appears that the 84-month remission rate is higher with an 18-month fixed RTX regimen compared with AZA and 18-month tailored RTX. Also, extending RTX to 36 months does not appear to reduce the long-term relapse rate compared with the 18-month fixed RTX regimen. However, as this study was underpowered to make this comparison, further prospective studies are needed to determine the potential long-term benefits of extending treatment in these patients.

Long-Term Rituximab Use to Maintain Remission of Antineutrophil Cytoplasmic Antibody-Associated Vasculitis: A Randomized Trial.

BACKGROUND: Biannual rituximab infusions over 18 months effectively maintain remission after a "standard" remission induction regimen for patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV). OBJECTIVE: To evaluate the efficacy of prolonged rituximab therapy in preventing AAV relapses in patients with granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA) who have achieved complete remission after completing an 18-month maintenance regimen. DESIGN: Randomized controlled trial. (ClinicalTrials.gov: NCT02433522). SETTING: 39 clinical centers in France. PATIENTS: 68 patients with GPA and 29 with MPA who achieved complete remission after the first phase of maintenance therapy. INTERVENTION: Rituximab or placebo infusion every 6 months for 18 months (4 infusions). MEASUREMENTS: The primary end point was relapse-free survival at month 28. Relapse was defined as new or reappearing symptoms or worsening disease, with a Birmingham Vasculitis Activity Score greater than 0. RESULTS: From March 2015 to April 2016, 97 patients (mean age, 63.9 years; 35% women) were randomly assigned, 50 to the rituximab and 47 to the placebo group. Relapse-free survival estimates at month 28 were 96% (95% CI, 91% to 100%) and 74% (CI, 63% to 88%) in the rituximab and placebo groups, respectively, an absolute difference of 22% (CI, 9% to 36%) with a hazard ratio of 7.5 (CI, 1.67 to 33.7) (P = 0.008). Major relapse-free survival estimates at month 28 were 100% (CI, 93% to 100%) versus 87% (CI, 78% to 97%) (P = 0.009), respectively. At least 1 serious adverse event developed in 12 patients (24%) in the rituximab group (with 9 infectious serious adverse events occurring among 6 patients [12%]) versus 14 patients (30%) in the placebo group (with 6 infectious serious adverse events developing among 4 patients [9%]). No deaths occurred in either group. LIMITATION: Potential selection bias based on previous rituximab response and tolerance. CONCLUSION: Extended therapy with biannual rituximab infusions over 18 months was associated with a lower incidence of AAV relapse compared with standard maintenance therapy. PRIMARY FUNDING SOURCE: French Ministry of Health and Hoffmann-La Roche.

Reducing the initial number of rituximab maintenance-therapy infusions for ANCA-associated vasculitides: randomized-trial post-hoc analysis.

OBJECTIVE: The randomized, controlled MAINRITSAN2 trial was designed to compare the capacity of an individually tailored therapy [randomization day 0 (D0)], with reinfusion only when CD19+ lymphocytes or ANCA had reappeared, or if the latter's titre rose markedly, with that of five fixed-schedule 500-mg rituximab infusions [D0 + D14, then months (M) 6, 12 and 18] to maintain ANCA-associated vasculitis (AAV) remissions. Relapse rates did not differ at M28. This ancillary study was undertaken to evaluate the effect of omitting the D14 rituximab infusion on AAV relapse rates at M12. METHODS: MAINRITSAN2 trial data were subjected to post-hoc analyses of M3, M6, M9 and M12 relapse-free survival rates in each arm as primary end points. Exploratory subgroup analyses were run according to CYC or rituximab induction and newly diagnosed or relapsing AAV. RESULTS: At M3, M6, M9 and M12, respectively, among the 161 patients included, 79/80 (98.8%), 76/80 (95%), 74/80 (92.5%) and 73/80 (91.3%) from D0, and 80/81 (98.8%), 78/81 (96.3%), 76/81 (93.8%) and 76/81 (93.8%) from D0+D14 groups were alive and relapse-free. No between-group differences were observed. Results were not affected by CYC or rituximab induction, or newly diagnosed or relapsing AAV. CONCLUSIONS: We were not able to detect a difference between the relapse-free survival rates for up to M12 for the D0 and D0+D14 rituximab-infusion groups, which could suggest that omitting the D14 rituximab remission-maintenance dose did not modify the short-term relapse-free rate. Nevertheless, results at M12 may also have been influenced by the rituximab-infusion strategies for both groups.

Comparison of individually tailored versus fixed-schedule rituximab regimen to maintain ANCA-associated vasculitis remission: results of a multicentre, randomised controlled, phase III trial (MAINRITSAN2).

OBJECTIVE: To compare individually tailored, based on trimestrial biological parameter monitoring, to fixed-schedule rituximab reinfusion for remission maintenance of antineutrophil cytoplasm antibody (ANCA)-associated vasculitides (AAVs). METHODS: Patients with newly diagnosed or relapsing granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA) in complete remission after induction therapy were included in an open-label, multicentre, randomised controlled trial. All tailored-arm patients received a 500 mg rituximab infusion at randomisation, with rituximab reinfusion only when CD19+B lymphocytes or ANCA had reappeared or ANCA titre rose markedly based on trimestrial testing until month 18. Controls received a fixed 500 mg rituximab infusion on days 0 and 14 postrandomisation, then 6, 12 and 18 months after the first infusion. The primary endpoint was the number of relapses (new or reappearing symptom(s) or worsening disease with Birmingham Vasculitis Activity Score (BVAS)>0) at month 28 evaluated by an independent Adjudication Committee blinded to treatment group. RESULTS: Among the 162 patients (mean age: 60 years; 42% women) included, 117 (72.2%) had GPA and 45 (27.8%) had MPA. Preinclusion induction therapy included cyclophosphamide for 100 (61.7%), rituximab for 61 (37.6%) and methotrexate for 1 (0.6%). At month 28, 21 patients had suffered 22 relapses: 14/81 (17.3%) in 13 tailored-infusion recipients and 8/81 (9.9%) in 8 fixed-schedule patients (p=0.22). The tailored-infusion versus fixed-schedule group, respectively, received 248 vs 381 infusions, with medians (IQR) of 3 (2-4) vs 5 (5-5) administrations. CONCLUSION: AAV relapse rates did not differ significantly between individually tailored and fixed-schedule rituximab regimens. Individually tailored-arm patients received fewer rituximab infusions. TRIAL REGISTRATION NUMBER: NCT01731561; Results.

PKD2-Related Autosomal Dominant Polycystic Kidney Disease: Prevalence, Clinical Presentation, Mutation Spectrum, and Prognosis.

BACKGROUND: PKD2-related autosomal dominant polycystic kidney disease (ADPKD) is widely acknowledged to be of milder severity than PKD1-related disease, but population-based studies depicting the exact burden of the disease are lacking. We aimed to revisit PKD2 prevalence, clinical presentation, mutation spectrum, and prognosis through the Genkyst cohort. STUDY DESIGN: Case series, January 2010 to March 2016. SETTINGS & PARTICIPANTS: Genkyst study participants are individuals older than 18 years from 22 nephrology centers from western France with a diagnosis of ADPKD based on Pei criteria or at least 10 bilateral kidney cysts in the absence of a familial history. Publicly available whole-exome sequencing data from the ExAC database were used to provide an estimate of the genetic prevalence of the disease. OUTCOMES: Molecular analysis of PKD1 and PKD2 genes. Renal survival, age- and sex-adjusted estimated glomerular filtration rate. RESULTS: The Genkyst cohort included 293 patients with PKD2 mutations (203 pedigrees). PKD2 patients with a nephrology follow-up corresponded to 0.63 (95% CI, 0.54-0.72)/10,000 in Brittany, while PKD2 genetic prevalence was calculated at 1.64 (95% CI, 1.10-3.51)/10,000 inhabitants in the European population. Median age at diagnosis was 42 years. Flank pain was reported in 38.9%; macroscopic hematuria, in 31.1%; and cyst infections, in 15.3% of patients. At age 60 years, the cumulative probability of end-stage renal disease (ESRD) was 9.8% (95% CI, 5.2%-14.4%), whereas the probability of hypertension was 75.2% (95% CI, 68.5%-81.9%). Although there was no sex influence on renal survival, men had lower kidney function than women. Nontruncating mutations (n=36) were associated with higher age-adjusted estimated glomerular filtration rates. Among the 18 patients with more severe outcomes (ESRD before age 60), 44% had associated conditions or nephropathies likely to account for the early progression to ESRD. LIMITATIONS: Younger patients and patients presenting with milder forms of PKD2-related disease may not be diagnosed or referred to nephrology centers. CONCLUSIONS: Patients with PKD2-related ADPKD typically present with mild disease. In case of accelerated degradation of kidney function, a concomitant nephropathy should be ruled out.

Long-Term Outcomes Among Participants in the WEGENT Trial of Remission-Maintenance Therapy for Granulomatosis With Polyangiitis (Wegener's) or Microscopic Polyangiitis.

OBJECTIVE: Findings from the WEGENT trial and other short-term studies have suggested that azathioprine (AZA) or methotrexate (MTX) could effectively maintain remission of granulomatosis with polyangiitis (Wegener's) (GPA) or microscopic polyangiitis (MPA). This study was undertaken to examine whether differences in rates of relapse or adverse events would appear after discontinuation of these 2 maintenance regimens, when assessed over a longer followup period. METHODS: Long-term outcomes in patients enrolled in the WEGENT trial were analyzed according to their randomized treatment group (AZA or MTX). Parameters at trial entry were evaluated as potential prognostic factors for death, relapse, or damage in multivariate models. RESULTS: Data from 10 years of followup were available for 112 (88.8%) of the 126 original trial participants. The median followup time was 11.9 years (95% confidence interval [95% CI] 11.3-12.5 years). In patients receiving AZA and those receiving MTX, the 10-year overall survival rates were 75.1% (95% CI 64.8-86.9%) and 79.9% (95% CI 70.3-90.8%) (P = 0.56), respectively, and relapse-free survival rates were 26.3% (95% CI 17.3-40.1%) and 33.5% (95% CI 23.5-47.7%) (P = 0.29), respectively. No between-treatment differences were observed with regard to rates of relapse, adverse events, damage, survival without severe side effects, and survival without relapse and severe side effects. In analyses limited to the 97 patients with GPA, no between-treatment differences in survival rates were observed. The 10-year relapse-free survival rate was lower in patients with GPA than in patients with MPA. However, in the multivariate analysis, anti-proteinase 3 antineutrophil cytoplasmic antibody (ANCA) positivity, and not GPA, was retained as being independently associated with the relapse rate. CONCLUSION: The results of this long-term analysis confirm that AZA and MTX are comparable treatment options for maintaining remission of GPA or MPA. Despite achieving good overall survival with these treatments, relapse rates, adverse events, and damage remain matters of concern and further studies are needed to reduce their frequency in these ANCA-associated vasculitides.

Anti-alpha-actinin antibodies are part of the anti-cell membrane antibody spectrum that characterize patients with lupus nephritis.

Anti-membrane autoantibodies (MbA) have been reported in sera from patients with lupus nephritis (LN) but the targets of the MbA remain to be explored, which is the aim of the current study. Sera were collected from 40 patients with LN determined by renal biopsy, and from 30 systemic lupus erythematosus (SLE) patients without clinical evidence of LN. Thirty autoimmune disease control patients (rheumatoid arthritis, Sjögren's syndrome and systemic sclerosis), and 30 healthy controls were also included. Using flow cytometry, the presence of anti-MbA was explored revealing that IgG anti-MbA positivity was associated with LN (62.5% vs 13.3%) when compared to non-LN SLE patients, autoimmune disease patients (6.7%) and healthy controls (0%). Next, using purified plasma membrane fractions from human embryonic kidney (HEK) cells, the more prominent targets and their occurrence rates were located at 50 kDa, 60/65 kDa, 90 kDa, 110 kDa, 180 kDa and 220 kDa. Alpha-actinin (110 kDa) autoAb was characterized as a major target in LN patients positive for anti-MbA, and anti-MbA binding activity was reduced (36.9 ± 13.7%) in the presence of α-actinin. Laminin (200 kDa) was also characterized as a minor target, which was not the case for annexin A2 (36 kDa). Finally, anti-MbA IgG subclass analysis indicated a predominance of IgG2. In conclusion, IgG anti-MbA were detected at high levels in LN patients supporting a primary pathogenic role for anti-MbA and anti-MbA/α-actinin+ in LN that needs further research.

[Prospective study of drug-induced interstitial nephritis in eleven French nephrology units]. / Médicaments à l'origine d'insuffisances rénales aiguës allergiques en France en 2013.

OBJECTIVE: Certain medications have been associated with drug-induced acute interstitial nephritis (AIN), but few prospective studies have been published. This prospective observational study aims to record and assess incidents of drug-induced AIN observed over a period of one year in nephrology units in France. The goal is to determine which medications are involved in AIN and to expound the clinical and biological presentation, management, and evolution of AIN. METHODS: Between April 2012 and April 2013, drug-associated cases of AIN were prospectively recorded in 24 patients registered in 11 nephrology units that belong to the Société de Néphrologie de l'Ouest (SNO). Data sheets, including suspected and concomitant drug(s), kidney function assessment, biological disturbances, clinical signs, histological data, management, and evolution, were collected by the Rennes Regional Pharmacovigilance Center and recorded in the French pharmacovigilance database. RESULTS: In order, the most frequently involved medications in the AIN cases were: vitamin K antagonists (33.3% of the cases, almost exclusively fluindione), antibiotics (20.8% of cases) non-steroidal anti-inflammatory drugs (20.8% of cases), and proton pump inhibitors (16.7% of cases). The mean delay of onset to AIN was 8.3 weeks. At the time of diagnosis, mean serum creatinine was 366 µM, higher for vitamin K antagonists (VKAs), except in the case of warfarin. During the course of an AIN event, 70% of patients had complete blood count and/or urine analysis abnormalities, 55% had clinical signs of systemic hypersensitivity, and 13% of patients had hepatic disorders. Renal biopsies were performed in 54% of patients; however, only 37% of patients requiring therapeutic anticoagulation underwent a biopsy. Suspected drugs were discontinued in all patients and the majority was treated with oral corticosteroids. Renal function often continued to be impaired after an AIN event. At baseline, 25% of patients had chronic kidney disease (CKD); after an AIN event, 67% of patients were noted to have CKD. CONCLUSION: Physicians need to be aware of the possibility of drug-induced acute interstitial nephritis as a common cause of acute kidney injury (AKI). This study supports increased vigilance when prescribing three therapeutic classes frequently associated with AIN: antibiotics, NSAIDs and PPIs (especially in instances of polypharmacy), which were associated with two thirds of the AIN cases in this study. Fluindione, an oral anticoagulant exclusively marketed in Luxembourg and France where it constitutes the vast majority of VKA prescriptions, was associated with one third of the AIN cases alone, making it a common possible culprit of drug-induced AIN, warranting particular attention.

CTX-M-93, a CTX-M variant lacking penicillin hydrolytic activity.

Extended-spectrum ß-lactamases (ESBLs) of the CTX-M type are increasingly being reported worldwide, with more than 90 known variants. Clinical Escherichia coli isolate Bre-1 was isolated in 2009 and displayed an unusual ESBL phenotype, made of a synergy image between expanded cephalosporins and clavulanic acid discs and susceptibility to penicillins. E. coli Bre-1 harbored a novel CTX-M-encoding gene, designated bla(CTX-M-93). CTX-M-93 differed from CTX-M-27 by only a single L169Q substitution. Compared to CTX-M-27, CTX-M-93 conferred higher MICs of ceftazidime for E. coli (MIC of 8 versus 1.5 µg/ml) and decreased MICs of other expanded-cephalosporins (MIC of cefotaxime of 1 versus 32 µg/ml) and penicillins (MIC of ticarcillin of 0.5 versus >256 µg/ml). A comparison of enzymatic properties revealed that the L169Q substitution led to a decreased Km for ceftazidime (25.5 versus 330 µM) but decreased hydrolytic activity against good substrates, such as cefotaxime (kcat of 0.6 versus 113 s(-1)), probably owing to the alteration of the omega loop positioning during the catalytic process. The blaCTX-M-93 gene was surrounded by the ISEcp1 and IS903 elements and inserted onto a 150-kb non-self-transferrable IncF-type plasmid. E. coli Bre-1 belongs to phylogroup D and is of multilocus sequence type (MLST) 624, a sequence type found only in rare Spanish CTX-M-14-producing E. coli isolates. We have characterized a novel CTX-M variant, CTX-M-93, lacking significant penicillin hydrolysis but with increased ceftazidime hydrolysis.

Glomerular antibodies in lupus nephritis.

Lupus nephritis (LN) remains the most common severe manifestation of systemic lupus erythematosus (SLE) characterized by the presence of autoantibodies (Abs) that are believed to play a central role in the pathogenesis of LN. Among more than 100 Abs reported in SLE, only a few display a direct glomerular binding capacity. Such antiglomerular Abs are detected at the onset of the disease before antinuclear Abs detection and proteinuria, this detection is associated with the related autoantigen overexpression. Antiglomerular Abs are able to interfere with cell metabolism, to penetrate living cells, and to induce glomerular cell proliferation. In addition, antiglomerular Abs could be nephritogenic causing proteinuria, particularly when they cross-react with anti-dsDNA Abs. Antiglomerular Abs encompass anti-α-actinin, anti-laminin-1, antifibronectin, antimyosin, and anticollagen Abs. The pathogenic activity of anti-α-actinin Abs has been demonstrated in non-autoimmune mice after immunization with α-actinin, but not with dsDNA, leading to a SLE-like disease with proteinuria and glomerular immune complex deposition. Similarly, extracorporeal immunoabsorption to remove anti-laminin-1 Abs reduces kidney-Abs deposition and proteinuria in mice and humans proving their pathogenic effect. Altogether this suggests that antiglomerular Abs participate, at least at the beginning, in the glomerular immune complex deposition and in the kidney damage.

IL-6 modulates CD5 expression in B cells from patients with lupus by regulating DNA methylation.

B lymphocytes from patients with systemic lupus erythematosus (SLE) are characterized by reduced expression levels of membrane CD5. Recent studies from our laboratory have revealed that the level of membrane CD5 is determined by the relative level of two alternative CD5 isoforms; CD5-E1A, which is expressed on the membrane, and CD5-E1B, which is retained in the cytoplasm. Using bisulfite sequencing and methylation-sensitive endonuclease assays we show that the promoter for the alternative CD5-E1B isoform is demethylated in B cells from patients with SLE but not in healthy controls. We go on to show that differential methylation is more pronounced following BCR engagement. As a result of this demethylation, CD5-E1B mRNA is transcribed at the expense of CD5-E1A mRNA transcription. We provide further evidence that production of high IL-6 levels by SLE B cells abrogates the ability of SLE B cells to induce DNA methyl transferase (DNMT1) and then to methylate DNA, an effect that is reversed in the presence of a blocking Ab to the IL-6 receptor. The pattern of demethylation of CpG islands in the CD5-E1B promoter in SLE B cells is similar to those in B cells from healthy controls stimulated in the presence of IL-6, or treated with the methylation inhibitor PD98059. The study reveals that engagement of the BCR with constitutive IL-6 down-regulates the level of membrane CD5, which negatively regulates BCR signaling, in SLE B cells. This altered signaling could, in turn, promote the activation and expansion of autoreactive B cells in SLE patients.