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Dive into the research topics where Mehdi Khellaf is active.

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Featured researches published by Mehdi Khellaf.


The New England Journal of Medicine | 2008

Azathioprine or Methotrexate Maintenance for ANCA-Associated Vasculitis

Christian Pagnoux; Alfred Mahr; Mohamed Hamidou; Jean-Jacques Boffa; M. Ruivard; J.-P. Ducroix; Xavier Kyndt; François Lifermann; Thomas Papo; Marc Lambert; José Le Noach; Mehdi Khellaf; Dominique Merrien; Xavier Puéchal; S. Vinzio; Pascal Cohen; Luc Mouthon; Jean-François Cordier; Loïc Guillevin

BACKGROUND Current standard therapy for Wegeners granulomatosis and microscopic polyangiitis combines corticosteroids and cyclophosphamide to induce remission, followed by a less toxic immunosuppressant such as azathioprine or methotrexate for maintenance therapy. However, azathioprine and methotrexate have not been compared with regard to safety and efficacy. METHODS In this prospective, open-label, multicenter trial, we randomly assigned patients with Wegeners granulomatosis or microscopic polyangiitis who entered remission with intravenous cyclophosphamide and corticosteroids to receive oral azathioprine (at a dose of 2.0 mg per kilogram of body weight per day) or methotrexate (at a dose of 0.3 mg per kilogram per week, progressively increased to 25 mg per week) for 12 months. The primary end point was an adverse event requiring discontinuation of the study drug or causing death; the sample size was calculated on the basis of the primary hypothesis that methotrexate would be less toxic than azathioprine. The secondary end points were severe adverse events and relapse. RESULTS Among 159 eligible patients, 126 (79%) had a remission, were randomly assigned to receive a study drug in two groups of 63 patients each, and were followed for a mean (+/-SD) period of 29+/-13 months. Adverse events occurred in 29 azathioprine recipients and 35 methotrexate recipients (P=0.29); grade 3 or 4 events occurred in 5 patients in the azathioprine group and 11 patients in the methotrexate group (P=0.11). The primary end point was reached in 7 patients who received azathioprine as compared with 12 patients who received methotrexate (P=0.21), with a corresponding hazard ratio for methotrexate of 1.65 (95% confidence interval, 0.65 to 4.18; P=0.29). There was one death in the methotrexate group. Twenty-three patients who received azathioprine and 21 patients who received methotrexate had a relapse (P=0.71); 73% of these patients had a relapse after discontinuation of the study drug. CONCLUSIONS These results do not support the primary hypothesis that methotrexate is safer than azathioprine. The two agents appear to be similar alternatives for maintenance therapy in patients with Wegeners granulomatosis and microscopic polyangiitis after initial remission. (ClinicalTrials.gov number, NCT00349674.)


Arthritis & Rheumatism | 2013

Eosinophilic granulomatosis with polyangiitis (Churg-Strauss): clinical characteristics and long-term followup of the 383 patients enrolled in the French Vasculitis Study Group cohort.

Cloé Comarmond; Christian Pagnoux; Mehdi Khellaf; Jean-François Cordier; Mohamed Hamidou; Jean-François Viallard; F. Maurier; Stéphane Jouneau; Boris Bienvenu; Xavier Puéchal; O. Aumaître; Guillaume Le Guenno; Alain Le Quellec; Ramiro Cevallos; Olivier Fain; Bertrand Godeau; R. Seror; Alfred Mahr; P. Guilpain; P. Cohen; Achille Aouba; Luc Mouthon; Loïc Guillevin

OBJECTIVE Earlier studies of eosinophilic granulomatosis with polyangiitis (Churg-Strauss) (EGPA), with limited patient numbers and followup durations, demonstrated that clinical presentation at diagnosis, but not outcome, differed according to antineutrophil cytoplasmic antibody (ANCA) status. This study was undertaken to describe the main characteristics of a larger patient cohort and their long-term outcomes. METHODS A retrospective study of EGPA patients in the French Vasculitis Study Group cohort who satisfied the American College of Rheumatology criteria and/or Chapel Hill definitions was conducted. Patient characteristics and outcomes were compared according to ANCA status and year of diagnosis. RESULTS We identified 383 patients diagnosed between 1957 and June 2009 (128 [33.4%] before 1997 or earlier) and followed up for a mean±SD of 66.8±62.5 months. At diagnosis, their mean±SD age was 50.3±15.7 years, and 91.1% had asthma (duration 9.3±10.8 years). Main manifestations included peripheral neuropathy (51.4%); ear, nose, and throat (ENT) signs (48.0%); skin lesions (39.7%); lung infiltrates (38.6%); and cardiomyopathy (16.4%). Among the 348 patients tested at diagnosis for ANCA, the 108 ANCA-positive patients (31.0%) had significantly more frequent ENT manifestations, peripheral neuropathy, and/or renal involvement, but less frequent cardiac manifestations, than the ANCA-negative patients. Vasculitis relapses occurred in 35.2% of the ANCA-positive versus 22.5% of the ANCA-negative patients (P=0.01), and 5.6% versus 12.5%, respectively, died (P<0.05). The 5-year relapse-free survival rate was 58.1% (95% confidence interval [95% CI] 45.6-68.6) for ANCA-positive and 67.8% (95% CI 59.8-74.5) for ANCA-negative patients (P=0.35). Multivariable analysis identified cardiomyopathy, older age, and diagnosis during or prior to 1996 as independent risk factors for death and lower eosinophil count at diagnosis as predictive of relapse. CONCLUSION The characteristics and long-term outcomes of EGPA patients differ according to their ANCA status. Although EGPA relapses remain frequent, mortality has declined, at least since 1996.


Blood | 2008

Rituximab efficacy and safety in adult splenectomy candidates with chronic immune thrombocytopenic purpura - results of a prospective multicenter phase 2 study

Bertrand Godeau; Raphael Porcher; Olivier Fain; François Lefrère; Pierre Fenaux; Stéphane Cheze; Anne Vekhoff; Marie-Paule Chauveheid; Jérôme Stirnemann; Lionel Galicier; Emmanuelle Bourgeois; Stephanie Haiat; Bruno Varet; Michel Leporrier; Thomas Papo; Mehdi Khellaf; Marc Michel; Philippe Bierling

Whether rituximab could effectively and safely avoid splenectomy for adults with chronic immune thrombocytopenic purpura (ITP) remains unresolved. A multicenter, prospective, open-label, single-arm, phase 2 trial was conducted to assess rituximab safety and efficacy in adult splenectomy candidates with chronic ITP. Sixty patients with chronic (>or= 6 months) ITP and platelet counts less than 30 x 10(9)/L received a weekly intravenous infusion of rituximab (375 mg/m(2)) for 4 weeks. All other ITP treatments were stopped. A good response was defined as a platelet count 50 x 10(9)/L or more, with at least a doubling of the initial value at 1 and 2 years after the first rituximab infusion. Patients who required another treatment during follow up were considered nonresponders. Sixteen patients experienced transient side effects that necessitated treatment discontinuation for only 1. Good 1-year responses were obtained in 40% of the patients (24/60 [95% confidence interval: 28%-52%]). At 2 years, 33.3% (20/60 patients) had good responses and 6.7% (4/60) had sustained platelet counts of 30 x 10(9)/L or more without treatment. Thirty-six (60%) patients failed to respond; 25 underwent splenectomy. Based on these results, rituximab was an apparently safe and effective splenectomy-avoiding option in some adults with chronic ITP. This trial is registered at http://clinicaltrials.gov as NCT00225875.


Medicine | 2006

Characteristics and long-term outcome of 15 episodes of systemic lupus erythematosus-associated hemophagocytic syndrome.

Olivier Lambotte; Mehdi Khellaf; Hicham Harmouche; Brigitte Bader-Meunier; Véronique Manceron; Cécile Goujard; Zahir Amoura; Bertrand Godeau; Jean-Charles Piette; Jean-François Delfraissy

Abstract: Reactive hemophagocytic syndrome (HS) occurs mainly in the setting of serious infections and lymphomas. HS can occur in the course of 2 active systemic diseases, without simultaneous infection: adult Still disease and systemic lupus erythematosus (SLE). Observations of specific lupus-associated HS are rare, and the long-term outcome of these patients with active SLE is unknown. We retrospectively studied 15 episodes of SLE-associated HS in 12 patients (10 women, 2 men) and noted the long-term outcome. HS occurred at a mean age of 25 years. All patients were febrile with ≥2 cytopenias, and bone marrow aspiration indicated hemophagocytosis. HS revealed SLE in 9 patients and recurred in 3. The main features of SLE-associated HS were a low frequency of hepatosplenomegaly, a high frequency of heart involvement (5 pericarditis, 4 myocarditis requiring transfer to intensive care unit), and a low C-reactive protein level (mean, 15 mg/L). Cutaneous-mucous symptoms of SLE, arthritis, and nephritis were present respectively in 8 (53%), 6 (40%), and 4 (27%) episodes, but symptoms of SLE were absent in 4 episodes at admission. All patients had anti-nuclear antibodies when the HS occurred. Anti-double-stranded DNA antibodies were present in 12 episodes. Treatment was steroids in 14 cases but cyclophosphamide was the only treatment able to control HS in 2 cases. All the cases of SLE-associated HS were controlled by the immunosuppressive regimen. Intravenous immunoglobulins seemed poorly effective. No infectious agent was found. Clinical presentations of the 23 patients with SLE-associated HS described in the literature were reviewed and were similar to those of the current series. The mean follow-up was 88 months (range, 7-240 mo). One patient died at 15 months (sepsis). Among the 5 patients with a follow-up >8 years, 4 always had active disease. During the follow-up of SLE, immunosuppressive drugs were added in 8 patients (cyclophosphamide in 7, azathioprine in 3, mycophenolate mofetil in 2) with significant adverse drug reactions. In the long-term, SLE-associated HS seems to define a severe SLE form with frequent flares, possible HS recurrences, and the need for prolonged immunosuppression. Abbreviations: CRP = C-reactive protein, HS = hemophagocytic syndrome, ICU = intensive care unit, IV Ig = intravenous immunoglobulins, SLE = systemic lupus crythematosus, SLEDAI = Systemic Lupus Erythematosus Disease Activity Index.


JAMA Internal Medicine | 2003

Autoimmune Thrombocytopenic Purpura and Helicobacter pylori Infection

Marc Michel; Mehdi Khellaf; Lionel Desforges; Ketty Lee; Annette Schaeffer; Bertrand Godeau; Philippe Bierling

BACKGROUND The mechanisms triggering the production of platelet autoantibodies in autoimmune thrombocytopenic purpura (AITP) are poorly understood. Recently, marked improvements in platelet counts have been reported in patients with AITP and concurrent Helicobacter pylori infection after eradication of H pylori by a standard antibiotic regimen. We looked for an association between H pylori infection and AITP in adults. METHODS Fifty-one adults of white French origin, negative for human immunodeficiency virus (mean +/- SD age, 40 +/- 19.8 years), with AITP and a platelet count of less than 50 x 10(3)/microL at onset were included. Thirty-five consecutive nonthrombocytopenic patients (mean +/- SD age, 43 +/- 22 years) of the same origin and with unknown H pylori status served as control subjects. Antibodies against H pylori were detected by means of an agglutination method in both patients and control subjects. Sex ratio, mean age, hemorrhagic manifestations, response to corticosteroid therapy, and final outcome were compared in H pylori-negative and H pylori-positive patients with AITP. To test for a possible molecular mimicry mechanism, we also used an immunoblot assay to look for specific H pylori antibodies in platelet eluates from 3 H pylori-positive patients with AITP. RESULTS Seroprevalence of H pylori in patients with AITP (15 [29%]) was not significatively different from that in control subjects (10 [29%]). The H pylori-positive and H pylori-negative patients with AITP did not differ in main characteristics at AITP onset, response rate to corticosteroids, and final outcome. None of the 3 patients investigated had H pylori antibodies in platelet eluates. CONCLUSION Although the role of H pylori in a subgroup of patients with AITP cannot be excluded, we found no evidence of an association between H pylori infection and AITP.


Journal of Clinical Investigation | 2013

B cell depletion in immune thrombocytopenia reveals splenic long-lived plasma cells

Matthieu Mahévas; Pauline Patin; François Huetz; Marc Descatoire; Nicolas Cagnard; Christine Bole-Feysot; Simon Le Gallou; Mehdi Khellaf; Olivier Fain; David Boutboul; Lionel Galicier; M. Ebbo; Olivier Lambotte; M. Hamidou; Philippe Bierling; Bertrand Godeau; Marc Michel; Jean-Claude Weill; Claude-Agnès Reynaud

Primary immune thrombocytopenia (ITP) is a disorder caused by autoantibody-mediated platelet destruction and decreased platelet production. Rituximab, a B cell-depleting agent, has become the first-line treatment for ITP; however, patients with refractory disease usually require splenectomy. We identified antibody-secreting cells as the major splenic B cell population that is resistant to rituximab. The phenotype, antibody specificity, and gene expression profile of these cells were characterized and compared to those of antibody-secreting cells from untreated ITP spleens and from healthy tissues. Antiplatelet-specific plasma cells (PC) were detected in the spleens of patients with ITP up to 6 months after rituximab treatment, and the PC population displayed a long-lived program similar to the one of bone marrow PC, thus explaining for most of these patients the absence of response to rituximab and the response to splenectomy. When analyzed by multiplex PCR at the single-cell level, normal splenic PC showed a markedly different gene expression profile, with an intermediate signature, including genes characteristic of both long-lived PC and proliferating plasmablasts. Surprisingly, long-lived PC were not detected in untreated ITP spleens. These results suggest that the milieu generated by B cell depletion promotes the differentiation and settlement of long-lived PC in the spleen.


Rheumatology | 2014

Rituximab for induction and maintenance treatment of ANCA-associated vasculitides: a multicentre retrospective study on 80 patients

Pierre Charles; Antoine Néel; Nathalie Tieulie; Arnaud Hot; Grégory Pugnet; Olivier Decaux; I. Marie; Mehdi Khellaf; Jean-Emmanuel Kahn; Alexandre Karras; Jean-Marc Ziza; Christophe Deligny; Colas Tcherakian; Loïc Guillevin

OBJECTIVES Rituximab has been shown to induce remission of ANCA-associated vasculitides (AAVs). Our study was undertaken to describe AAV clinical responses to rituximab used for remission-induction and/or maintenance therapy, assess rituximabs safety profile and evaluate French clinical practices. METHODS This retrospective study concerned AAV patients who had received one or more rituximab infusion between 2002 and January 2011 and had follow-up lasting ≥12 months. RESULTS Eighty patients were included, most with refractory or relapsing AAV: 70 (88%) with granulomatosis with polyangiitis (GPA), 9 (11%) with microscopic polyangiitis and 1 (1%) with eosinophilic GPA. Rituximab was the first agent used to induce remission in 73 patients. The two most commonly administered regimens were an infusion of 375 mg/m(2)/week for 4 weeks (54 patients) and an infusion of 1 g every 2 weeks for a month (16 patients). Rituximab was first prescribed to maintain remission in seven patients. Respective 1-, 2-, and 3-year relapse-free survival rates after the first infusion were 80% (95% CI 72, 89), 63% (51, 77) and 52% (39, 70). Relapse-free survival was longer for patients receiving rituximab maintenance therapy (P = 0.002). Among 22 (28%) rituximab-treated patients experiencing severe adverse events, 12 (15%) had infectious complications leading to 4 (5%) deaths. Only 15 (19%) patients had received anti-pneumococcal vaccine before rituximab. CONCLUSION Rituximab was able to induce AAV remission and seemed to maintain remission better than other agents, but caution is needed concerning its safety, especially regarding bacterial infections, in this population.


Blood | 2014

Safety and efficacy of rituximab in adult immune thrombocytopenia: results from a prospective registry including 248 patients

Mehdi Khellaf; Anaı̈s Charles-Nelson; Olivier Fain; Louis Terriou; Jean-François Viallard; Stéphane Cheze; J. Graveleau; Borhane Slama; S. Audia; M. Ebbo; Guillaume Le Guenno; Manuel Cliquennois; Gilles Salles; Caroline Bonmati; Lionel Galicier; Arnaud Hot; Olivier Lambotte; François Lefrère; Salimatou Sacko; Dieudonné Kilendo Kengue; Philippe Bierling; F. Roudot-Thoraval; Marc Michel; Bertrand Godeau

We conducted a prospective multicenter registry of 248 adult patients with immune thrombocytopenia (ITP) treated with rituximab to assess safety. We also assessed response and predictive factors of sustained response. In total, 173 patients received 4 infusions of 375 mg/m(2) and 72 received 2 fixed 1-g infusions 2 weeks apart. The choice of the rituximab regimen was based on the physicians preference and not patient characteristics. Overall, 38 patients showed minor intolerance to rituximab infusions; infusions had to be stopped for only 3 patients. Seven showed infection (n = 11 cases), with an incidence of 2.3 infections/100 patient-years. Three patients died of infection 12 to 14 months after rituximab infusions, but the role of rituximab was questionable. In total, 152 patients (61%) showed an overall initial response (platelet count ≥30 × 10(9)/L and ≥2 baseline value). At a median follow-up of 24 months, 96 patients (39%) showed a lasting response. On multivariate analysis, the probability of sustained response at 1 year was significantly associated with ITP duration <1 year (P = .02) and previous transient complete response to corticosteroids (P = .05). The pattern of response was similar with the 2 rituximab regimens. With its benefit/risk ratio, rituximab used off-label may remain a valid option for treating persistent or chronic ITP in adults. This trial was registered at www.clinicaltrials.gov as #NC1101295.


British Journal of Haematology | 2008

Antiphospholipid antibodies in adults with immune thrombocytopenic purpura

Carole Pierrot-Deseilligny Despujol; Marc Michel; Mehdi Khellaf; Michèle Gouault; Liliane Intrator; Philippe Bierling; Bertrand Godeau

To determine the clinical significance of antiphospholipid antibodies (aPL) in patients with immune thrombocytopenic purpura (ITP), anticardiolipin (aCL) (IgG and IgM) and lupus anticoagulant (LA) were sought at diagnosis in 215 ITP adults with platelets <50 × 109/l. aPL (aCL and/or LA) were detected in 55 patients (26%): aCL alone in 39 (18%), aCL and LA in 15 (7%) and LA alone in one (0·5%). LA was significantly associated with high IgG‐aCL levels (P = 0·001). Among age, sex, initial platelet count, bleeding score, acute or chronic ITP outcome, only younger age was significantly associated with LA‐positivity (mean age 29 ± 14 years vs. 45 ± 20 years, P = 0·002). After a median follow‐up of 31 months, 14/215 (7%) patients developed thrombosis (four arterial, 10 venous and/or pulmonary embolism); four of them (29%) had high aCL levels and LA. Multivariate analysis significantly associated thrombosis events only with age [hazard ratio (HR) = 1·6; 95% confidence interval (CI): 1·2–2·4], LA (HR: 9·9; 95% CI: 2·3–43·4) or high IgG‐aCL level (HR: 7·5; 95% CI; 1·8–31·5). Although the thrombosis rate was low, the significant associations between thrombosis and LA or high aCL level suggest that aPL should be tested at ITP diagnosis.


British Journal of Haematology | 2014

The temporary use of thrombopoietin‐receptor agonists may induce a prolonged remission in adult chronic immune thrombocytopenia. Results of a French observational study

Matthieu Mahévas; Olivier Fain; M. Ebbo; F. Roudot-Thoraval; Nicolas Limal; Mehdi Khellaf; N. Schleinitz; Philippe Bierling; Laeticia Languille; Bertrand Godeau; Marc Michel

Thrombopoietin‐receptor agonists (Tpo‐RAs) are highly effective in immune thrombocytopenia (ITP). Recently, cases of durable remission after Tpo‐RA discontinuation in adult ITP have been reported. We aimed to describe the subset of patients in whom transient Tpo‐RA therapy may induce a durable response. We studied all adults with primary ITP treated with at least one Tpo‐RA over a 5‐year period (n = 54) and seen at one of three participating referral centres in France. Tpo‐RAs were discontinued in 20 of 28 patients who achieved a complete response. We excluded six patients because a previous treatment at the start of Tpo‐RA treatment may have interfered with the response. Overall, eight patients with chronic ITP showed a sustained response [median follow‐up: 13·5 months (range 5–27 months)]. We could not identify a predictive factor of sustained response. In conclusion, a substantial proportion of ITP patients receiving Tpo‐RAs can maintain a durable response after treatment discontinuation.

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Philippe Bierling

Gulf Coast Regional Blood Center

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François Lefrère

Necker-Enfants Malades Hospital

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