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, Le purpura thrombopénique immunologique (PTI) est la plus fréquente des cytopénies auto-immunes

L. Rituximab, RTX, anticorps monoclonal anti-CD20) représente actuellement une des options thérapeutiques de deuxième ligne, avec un taux de réponse globale initiale d'environ 60%. Cependant, la majorité des patients rechute

. Matériels, Nous avons réalisé une étude rétrospective multicentrique française

, L'objectif principal était d'évaluer le taux de réponse global après une deuxième cure de rituximab. Les objectifs secondaires étaient d'identifier de potentiels facteurs prédictifs de réponse à une deuxième cure de RTX et d'évaluer la tolérance associée à une telle attitude thérapeutique

. Résultats, Parmi les répondeurs à la 1 ère cure de RTX (n=44), 34 patients (77%) étaient répondeurs à la deuxième cure. La réponse obtenue était similaire ou meilleure à celle obtenue lors de la cure précédente dans 76% des cas. La durée de réponse était similaire ou plus longue chez 60% des patients évaluables. Les patients n'ayant pas répondu à une première cure de RTX restaient non répondeurs. En analyse multivariée, la réponse à un re-traitement était fortement associée à l'obtention d'une réponse à la 1 ère cure, Cinquante patients étaient analysés. Quarante-trois patients (86%) avaient un PTI primaire. Ils avaient reçu une médiane de 3 lignes thérapeutiques [2-4] antérieures à la 1 ère cure de rituximab. L'âge médian au diagnostic du PTI était de 39 ans

, En cas de réponse à une première cure, un re-traitement par RTX apparaît comme une option thérapeutique efficace et bien tolérée dans la prise en charge du PTI

, Immune thrombocytopenia (ITP) is the most common auto-immune cytopenia. Rituximab (RTX, anti-CD20 monoclonal antibody) is one of the second-line treatments, with an initial overall response rate in 60% of patients. However, most patients relapse after this treatment, Mots-clés : purpura thrombopénique immunologique, rituximab, re-traitement Abstract Introduction

M. Patients, We performed a multicenter retrospective study, including adults ITP treated with two or more rituximab courses. Primary objective was to evaluate overall response rate after the second rituximab course. Secondary objectives were to identify predictive factors of response to a second course of rituximab and evaluate the safety of such a therapeutic strategy

. Results, at ITP diagnostic and 46 years [30.25-58] at first rituximab course. After a second rituximab course, an overall response was observed in 70 % of cases, with 60% of complete response. Among responders to the first course (n=44), 34 patients (77%) were responders to the second course. Compared to the first course, the type of response was similar or better in 76% of cases. Among evaluable patients (n=40), duration of response was similar or longer in 60% of cases. Patients who did not respond to the first rituximab neither respond to a second course