ALBERT

Description: Background L-asparaginase (L-ASP) is a key drug in the treatment of acute lymphoblastic leukemia (ALL). However the toxicity profile, especially hypersensitivities up to acute allergic reactions is a major drawback. GRASPA (eryaspase (proposed INN) or E-Coli L-Asparaginase encapsulated into red blood cells) is a new product under development with the aim of improving the tolerance of this enzyme. Asparagine is actively transported through the membrane of red blood cells (RBC) where it is hydrolyzed by the encapsulated L-ASP, the erythrocytes acting as "bioreactors". The RBC membrane shields against the anti-L-ASP antibody then avoiding binding to encapsulated L-ASP. Recently, a Phase III pivotal study of GRASPA in combination with COOPRALL chemotherapy protocols in patients with relapsed ALL demonstrated highly significant safety profile and clinical activity compared to control. However, there is an unmet medical need for patients who cannot receive current formulations of L-ASP. An expanded access program has recently been initiated in France to provide access for treatment with GRASPA in patients who are unable to receive other forms of L-ASP. Methods: This is a non randomized multicenter open label study, currently initiated in France. The primary objective of the EAP is to evaluate the tolerability of GRASPA. Patients under 55y of age presenting with de novo, relapsed or refractory ALL who are at risk to receive any other available L-ASP formulation are enrolled into this program. Patients with known allergic reactions to E.Coli L-ASP are also eligible. GRASPA is administrated every 2 to 3 weeks at a dose equivalent to 150 IU/kg of L-ASP during all chemotherapy courses intended to contain an asparaginase. Chemotherapy protocols are given according to the Investigator's choice. Patients are assessed regularly for safety and tolerability. The primary endpoint is tolerability; Key secondary endpoints include asparaginase activity, asparagine depletion, and clinical remission rates. An independent Safety Monitoring Board (DSMB) is set up, which will assess toxicities on yearly basis. Results As of time of June 2015, 13 patients were enrolled into the program. The first DSMB meeting reviewed the outcome of the first 7 patients enrolled into the program. Of the 7 pts (range 3 - 49 years), 5 males and 2 females were enrolled. Four pts presented with refractory disease and 3 with relapse, with all patients had evidence of allergies to 2 prior asparaginases (double allergies). There were 2 pts presenting with limiting toxicities, in the form of myelosupression, and streptococcal infection. There was no modification to the protocol recommended by the first DSMB An updated safety and clinical activity information on all patients will be provided. Conclusion: The EAP provides a potential treatment alternative for ALL patients, who are unable, or at risk of developing hypersensitivity reactions to prior asparaginases. The initial results from this program suggests that GRASPA is well tolerated, and may have a potential benefit in patients with double allergies. The program will be expanded to other European countries Disclosures Bertrand: ERYTECH Pharma: Consultancy, Membership on an entity's Board of Directors or advisory committees. Dombret:Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Recher:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Chugai: Research Funding; Amgen: Research Funding; Sunesis: Consultancy, Membership on an entity's Board of Directors or advisory committees. Salako:ERYTECH Pharma: Employment. Godfrin:ERYTECH Pharma: Employment. El Hariry:ERYTECH Pharma: Employment.

Description: Abstract 439 Background: TET genes have been implicated in DNA demethylation in mammals (Thalihani, Science, 2009; Ito, Nature 2010) and the TET2 gene is mutated in 15–22% of MDS and AML (Kosmider et al. Blood 2009, Nibourel et al. Blood 2010). Azacitidine (AZA) is a hypomethylating agent providing about 50% of responses in MDS and AML with low blast count (Lancet Oncol 2009, JCO 2010). Routine clinical and biological variables can predict OS with AZA, but are poor predictors of response to AZA (Itzykson et al. ASH 2009, and other abstract submitted to ASH 2010), while no consensus genetic predictor of response has been reported so far. Methods: In consecutive MDS (including RAEB-t and CMML) and AML post MDS (with 〉30% blasts) (AML/MDS) patients treated by AZA in 6 centers, we prospectively sequenced the TET2 gene from PBMC or BMNC DNA samples stored prior to AZA onset. Standard PCR and sequencing procedures were performed as previously described (Delhommeau et al, NEJM 2009), allowing detection of mutations in the entire coding sequence of the TET2 gene (exons 3 to 11). Patients were to receive AZA at the FDA/EMEA approved schedule (75mg/m2/d, 7d/4 weeks). Patients (pts) having received ≥ 1 cycle of AZA and who had bone marrow evaluation after ≥ 4 cycles, or who died or progressed before completion of 4 cycles were considered evaluable (the last 2 groups were considered as treatment failures). Responses were scored according to IWG 2006 criteria for MDS and to Cheson et al. (JCO 2003) for AML. Results: The study population included 103 pts: F/M: 36/67; median age 72 (range 43–91). Diagnosis at AZA onset was MDS in 89 (RAEB-1 n=20, RAEB-2 n=43, RAEB-t n=23, CMML-1 n=2, CMML-2 n=1; IPSS int-1 in 13, int-2 in 38, high in 36, undetermined in 2) and AML/MDS in 14 pts; 29 pts had previously been treated by LD AraC or intensive chemotherapy (IC). Cytogenetics according to IPSS was favorable in 48, intermediate in 20, unfavorable in 31, unknown in 4. 78 pts received the approved and 25 (24%) a reduced AZA schedule (mostly 75 mg/m2 for 5 days every 4 weeks). Median number of cycles was 7 [range 1–39] and median follow-up was 18.2 months. 21 TET2 mutations were found in 17 (17%) pts, including 12 frameshift (all inducing a premature STOP codon), 6 non sense and 3 missense mutations. Predicted TET2 protein length was preserved in 3, and truncated in 14 pts, respectively. Patients with mutated (MUT) TET2 had similar age, diagnosis, BM blast %, neutrophil and platelet counts as those with wild type (WT) TET2 (all p〉0.3), but less frequent unfavorable cytogenetics (6% vs 37%, p=0.02) and a trend for higher WBC (p=0.12), lower Hb (p=0.11) and more pretreatment by LD AraC or IC (47% vs 24%, p=0.08) than WT TET2 pts. The 2 groups received AZA at similar schedules (p=0.4) for a median of 6 [1-39] cycles (TET2 WT) or 11 [4-34] cycles (TET2 MUT, p=0.01). Ten WT pts (vs 0 MUT) received

Description: Abstract 3996 Background: AZA significantly improves OS in higher-risk MDS (including RAEB-t/AML) compared to conventional treatments (AZA 001 trial, Lancet Onc, 2009), but prognostic factors of response and OS to AZA remain largely unknown. We designed a prognostic score for OS in a cohort of AZA treated higher-risk MDS in a patient-named compassionate program (French ATU), and validated it in patients from the AZA 001 trial. Methods: Between Sept 2004 and Jan 2009, prior to AZA approval in Europe, IPSS int-2/high risk MDS (including RAEB-t) not previously treated with intensive chemotherapy (IC), allo SCT, or a hypomethylating agent were included in a compassionate program (ATU), and received AZA (planned schedule 75 mg/m2/d ×7 d every 28 d for ≥4 cycles). Independent prognostic factors of OS were individualized in a Cox model. A prognostic score was then developed based on those factors. After validation of the score as a continuous variable, pts were grouped in three distinct risk categories. We subsequently tried to validate this score in the 175 higher risk MDS pts treated with AZA at the same schedule in AZA 001 trial (4 of the 179 pts randomized to AZA in that trial did not start AZA). Results: The ATU cohort included 282 pts with de novo (74%) or therapy related (t) (26%) higher-risk MDS (IPSS int-2 in 54% high in 43%, at least int-2 in 2%). ECOG PS ≥2, RBC transfusion dependence ≥4 units/8 weeks and circulating blasts were present in 21%, 46% and 46% of pts respectively (resp). Cytogenetic risk was good, int, and poor in 31%, 17% and 47% (unknown in 5%). 10% pts had previously been treated with LD araC for their MDS. Multivariate analysis of survival retained PS ≥2 (HR= 2.0 [95% CI: 1.4–2.9]), RBC transfusion dependence ≥4 units/8 weeks (HR=1.9 [1.4-2.6]), presence of circulating blasts (HR=2.0 [1.5-2.7]), and IPSS cytogenetic risk (intermediate: HR=1.4 [0.8-2.3], poor: HR=3.0 [2.0-4.3]) as independent prognostic factors (all p

Description: Background :AZA improves overall survival (OS) in higher risk MDS, but only 50-60% of the patients respond, and median OS with AZA is only 20-24 months. As OS improvement is obtained at modest response rates, OS rather than response should probably remain the primary endpoint for all combinations with AZA, requiring large phase III trials with significant follow up. On the other hand, combinations that do not increase response will likely not improve OS. We therefore tested, based on a "pick the winner" approach, AZA combinations with the HDAC inhibitor VPA, LEN or IDA to identify, based on response, the most promising combination with AZA in higher risk MDS, that could be subsequently compared with AZA alone in a larger phase III study. Methods : AZA-PLUS (#NCT01342692)was an adaptive two-stage phase II trial based on Jung design (Stat Med.2008;27:568) that randomly assigned higher-risk MDS, low blast count AML (20-30%) and CMML to: AZA (75 mg/m2/d d1-7 of 28-day cycles); AZA plus LEN (10 mg/d on d1-14); AZA plus VPA( 50 mg/kg/d on d1-7; 35 mg/kg/d in patients〉 60y) or AZA plus IDA (10 mg/m2on d1 for the first 9 cycles). The primary end point was response rate (RR, including CR, PR, marrow CR, based on IWG 2006) of the combination arms vs AZA alone. Given a 30% RR with AZA alone, we considered that a ≥45% RR would make combination(s) promising. Controlling for type I and type II errors at 0.15 and 0.20, 40 patients per arm were to be enrolled at each stage. Any experimental arms with RR lower than those observed in the AZA arm at the first stage should be stopped. At the second stage, any arm with 〉 6 more responses than AZA alone should be selected for further testing. Secondary endpoint were ORR (RR+ stable disease with HI (HI) and OS. Results : After inclusion of 40 pts/arm (first stage) all experimental arms had at least the same number of responses as the control arm and were continued in second stage. Overall, 322 pts were enrolled from 06/2011 to 07/2017: 81, 80, 80, 81 in the AZA, AZA+VPA, AZA+LEN and AZA+IDA arms, respectively. Baseline characteristics were well-balanced across arms. Median age was 74.6 y, 213 pts were male, IPSS was INT-2 in 54% and High in 46%. IPSS Karyotype was fav, int and poor in 40%, 26% and 34%, respectively. Pts received a median of 7 cycles and median follow-up was 15.1 months. Prevalence of trial discontinuation due to adverse events was 32%, 29%, 28% and 31% in the AZA , AZA+VPA , AZA+LEN and AZA+IDA arms, respectively (p=0.95). Rates of hospitalization during the first 6 cycles were 38%, 44.7% , 55.1%, 59.7% in the AZA, AZA +VPA, AZA+LEN and AZA+IDA arms, respectively (p=0.028), suggesting increased myelosuppression in the experimental arms, especially in the LEN and IDA arm. In the control arm, 29 responses (CR+PR+mCR) after 6 cycles were observed, with 29, 25 and 29 responses observed in AZA+VPA , AZA+LEN and AZA+IDA arms, respectively. Thus, no combination demonstrated benefit over AZA. The RR was estimated at 34.8% (18.6% CR, 3.1% PR, and 13.0% mCR) and the ORR after 6 cycles was 40.4%. The RR after 6 cycles (35.8% for AZA, 36.2% for AZA+VPA, 31.2% for AZA+LEN, and 35.8% for AZA+IDA) and the ORR after 6 cycles (41.9% for AZA; 41.2% for AZA+VPA, 40.0% for AZA+LEN and 38.3% for AZA+IDA) were close across study arms. By multivariate analysis, factors associated with better ORR were higher Hb level (p=0.05), low fibrinogen (p=0.008) and low LDH (p=0.01). 17 (5%) pts were bridged to allogeneic SCT: 6 on AZA, 5 on AZA+VPA, none in the AZA+LEN arm and 6 on AZA+IDA arm (p=0.03). At the reference date of July 2018, median EFS was 16.6 months for in AZA, 14.5 months for in AZA+VPA, 15.1 months for in AZA+LEN and 13.2 months for in AZA+IDA (p=0.74) (Fig A). Multivariable Cox model selected Hb level (p=0.02), presence of circulating blasts (p

Description: Introduction : TP53 mutated (TP53m) MDS and AML have very poor outcome irrespective of the treatment received, including 40% responses (20% CR) with azacitidine (AZA) with short response duration and a median overall survival (OS) of about 8 months (Bejar, Blood 2014). APR-246 is a prodrug spontaneously converted to methylene quinuclidinone (MQ), a Michael acceptor that binds covalently to cysteines in mutant p53, leading to protein reconformation that reactivates its pro apoptotic and cell cycle arrest functions. The combination of AZA and APR 246 showed promising results in a phase Ib study in TP53m MDS (Sallman, ASH 2018). We report interim results of a GFM phase 2 study of AZA+ APR-246 in TP53m MDS and AML, conducted in parallel with a similar US MDS consortium study. Patients and Methods : The study included hypomethylating agent (HMA) naïve and not previously allografted intermediate, high or very high IPSS-R TP53m MDS and AML adult patients. Patients received APR-246 4500 mg IV /d (6 hour infusions) (days 1-4) followed by AZA 75 mg/m²/d (days 4-10) in 28 day cycles. Response (primary endpoint, assessed by IWG 2006 for MDS and ELN criteria for AML) was evaluated after 3 and 6 cycles in the intent to treat (ITT) population, ie all patients who had received any protocol treatment, and in patients who had at least a blood and bone marrow evaluation after cycle 3 (evaluable population). Allo-SCT, when possible, was proposed after 3 to 6 cycles, and treatment with reduced APR 246 and AZA doses could be continued after allo-SCT. Results : 53 patients were enrolled between Sept 2018 and July 2019 in 7 GFM centers, with a median age of 73 years (range 44-87), and M/F: 28/25. 34 patients had MDS (including 74% very high IPSS-R) and 19 had AML. IPSS-R cytogenetic risk was very poor in 30/34 MDS, and unfavorable in 18/19 AML, complex in 89% of the patients. Median baseline mutated TP53 VAF was 21% (range 3-76). Nineteen of the 53 patients had been included at least 7 months before date of analysis (25 July 2019), had received protocol treatment and were thus potentially evaluable for response after 6 treatment cycles (ITT population). One of them died after only one cycle from an unrelated cause (cerebral ischemic stroke), and 2 during the third cycle (from bleeding and sepsis, respectively). In the remaining 16 patients (evaluable population per protocol), the response rate was 75% including 9 (56%) CR, 3 (19%) marrow CR or stable disease with hematological improvement (HI), and 4 treatment resistance. In the ITT population, the response rate was 63%, including 47% CR, and 16% stable or marrow CR+ HI. Among CR patients, complete cytogenetic CR and negative NGS for TP53 mutation (VAF cutoff of 2%) were achieved in 7/9 (78%) and 8/8 (100%), respectively. So far, 1 patient has undergone allo-SCT. All 53 patients had received at least one treatment cycle, and no increased myelosuppression, compared with AZA alone, was apparent. Treatment related AEs observed in ≥ 20% of patients were febrile neutropenia in 19 (36%) and neurological AEs in 21 (40%) of the patients. The latter, reviewed with a neurological team, were mainly grade 1 or 2 and consisted of ataxia (n=13), sometimes associated with cognitive impairment (n=4), suggesting a cerebellar origin. Other patients experienced acute confusion (n=4), isolated dizziness (n=3) and facial paresthesia (n=1). Neurological AEs reached grade III in 3 cases (1 acute confusion, 2 ataxia). Occurrence of neurological AEs was correlated with lower glomerular filtration rate at treatment onset (p

Description: Abstract 843 Background: AZA prolongs survival in higher-risk MDS including patients (pts) with 20-29 % marrow blasts, now considered WHO-AML ( Lancet Onc, 2009). However, no large AML cohorts (especially with '30% marrow blasts) treated upfront with AZA have been reported. Methods: An AZA compassionate program (ATU) was initiated in France in Dec 2004 for higher risk MDS, and AML considered not candidates or refractory to intensive chemotherapy (IC). We retrospectively analyzed WHO AML pts having received at least 1 cycle of AZA in the 42 centers with complete pt reporting, excluding those previously treated by IC, allo SCT, low dose AraC or a hypomethylating agent. Results: 138 pts were included between Dec 2004 and Dec 2008; M/F: 86/52; median age 73 years (y) (range 31-87), 117 pts (85%) were 〉 65 y and 54 (40%) 〉75y. 65 pts (47%) had prior WHO MDS and 30 pts (22%) therapy related (tAML). 44 pts (32%) had 20-29% marrow blasts. Median WBC was 3.0 G/L [0.8-111.5]. Karyotype (MRC classification), was intermediate (int) in 60 pts,( including 38 normal (NK), and 7 isolated +8 ) adverse in 67 pts (including 42 -7/ del7q, 41 del5q/-5, 45 complex karyotype, two 3q26) and failed in 11 pts. With a median follow-up of 11.3 months, pts received a median of 4.5 AZA cycles (range 1-26). Treatment was according to FDA-EMEA approved schedule for MDS in 95 pts (69%) and a less intensive schedule (5d/4w, or 10 G/L (32 pts in our cohort) carried poorer prognosis ( 1 y OS of 27% vs 44% ,p=0.01); NK had better OS (1-y OS: 66%) than adverse cytogenetics (1-y OS: 30%, p=0.01) but also other “intermediate-risk” abnormalities (1-y OS: 30%, p=0.03). Marrow blast % did not influence OS and survival, whatever the cut off chosen. In particular, pts with 20-29 % marrow blasts had 22% AML response and 1 y OS of 50%, compared to 21% and 1 y OS of 35%, respectively, in pts with 〉30% marrow blasts (p=NS and NS, respectively). Prior MDS also had no influence on survival. Overall, 33 pts required hospitalization during treatment, mainly for neutropenic fever. A landmark analysis at the time of evaluation showed that achievement of CR, CRi or PR was associated with improved OS (1y-OS 55% vs 31%,p=0.007). In pts with no AML-IWG response, however, achievement of HI also predicted better survival: 1 y-OS 55% vs 19 %, p=0.02. In the 54 pts older than 75 y (ie pts generally considered unfit for IC), 12 (22%) had AML response including CR in 9 (17%) and 3 PR (5%). 1y-OS was 41 % vs 38% for younger pts (p=NS). Hospitalisation was needed in 31% of them vs 32% in younger pts (p=NS). Conclusion: In this untreated cohort of generally older AML pts considered non candidates for intensive chemotherapy, response rate was 21% and 1 y OS 40%. Higher WBC counts and adverse karyotype were associated with poorer OS, but marrow blast %, whatever the threshold chosen, had no influence on outcome. Age above 75 y was associated with similar response and 1y OS. Finally, pts without AML IWG responses but with improved cytopenias also appeared to have improved survival. Disclosures: Off Label Use: Azacytidine is approved by FDA and EMEA in the treatment of high risk MDS and AML up to 30% of bone marrow blast.. Fenaux:CELGENE: Research Funding; AMGEN: Research Funding.

Description: Background: RBC transfusions are required in most MDS, leading to iron overload which probably contributes to shortened survival (Malcovati, JCO, 2005). Consensus for indications of iron chelation therapy (CT) in MDS patients are recent (Gattermann Hemato/Oncol Clin2005; 19:supp1). A positive impact on survival of CT, clearly demonstrated in thalassemia, has not yet been prospectively reported in large MDS cohorts. Methods: We performed in 2005 a survey on hematological data, RBC transfusion requirement and CT in 170 MDS referred for RBC transfusion during a month period (May 15–June 15, 2005) to 18 French GFM centers (Rose, ASH 2006, abstr:2661). Survival of this prospective cohort was reanalyzed at the reference date of May 15, 2007. Results: 5 pts were lost to follow up. Median age of the remaining 165 pts was 77 (range 14–95).M/F 1.4. WHO: 13 pure RA (10%), 30 pure RARS (23%), 6 RCMD (5%),5 RCMD-RS (4%), 28 RAEB I (21%), 10 RAEB II (8%),11 5q- Sd (7%), 8 CMML (6%); 21 MDS unclass (16%). Karyotype: fav (12%), int (36%), unfav (22%), failure or ND (30%) IPSS: low 27%, Int1 32%, Int2 10%, high 2%, unavailable 29%. 76 pts (46%) received CT for at least 6 months, including 65 before May 2005, and 11 since May 2005. Median interval from diagnosis to onset of CT was 30 months (range 0–192). CT included: DFO continuous s/c (8h) (40mg/kg/d, 3 – 5d/w) n= 41, deferiprone alone (30 to 75 mg/kg/d) n= 5, Deferiprone + DFO s/c n= 5, deferasirox (20 to 30 mg/kg/d) n= 6 (Defined as “standard” chelation) and DFO s/c bolus (2 to 3g/week) n = 12 or DFO IV (50 to 100mg/kg/d once after each RBC transfusion) n= 7 (defined as “low” chelation). Median duration of CT was 35 months (6–138+). Median serum ferritin (SF) level was 569ng/ml (range 9–2500), 1436ng/ml (range 436–6572) and 1498ng/ml (range 272–7502) at diagnosis, onset of CT and last evaluation, respectively (resp). By comparison to non chelated pts, chelated pts had significantly higher number of RBC units transfused (mean 104 vs 57) (p1 in 27%, 53%, 20% of non chelated versus 49%,36%,15% of chelated pts with available IPSS, resp (p=0.044). Median overall survival from diagnosis (OS, Kaplan-Meier analysis) was 115 and 51 months in chelated and non chelated pts,resp (p〈 0.0001). After adjustment on other prognostic parameters (sex,age, IPSS, transfusion requirement) the survival difference remained significant. In IPSS 0 pts, median OS was not reached in chelated pts and 69 months in non chelated pts(p=0.002).In IPSS 0–1 pts, median OS was 115 months in chelated pts and 50 months in non chelated pts (p=0.003). Longer interval from diagnosis to onset of CT did not influence OS negatively but median OS was 120 months with “standard” chelation versus 69 months with “low “chelation (p

Description: Abstract 1307 Background. Mutation of MYD88 gene has recently been identified in activated B-cell like diffuse B-cell lymphoma, and enhanced JAK STAT and NF-kB signalling pathways. Whole exome sequencing study in Waldenstrom macroglobulinemia (WM) suggested a high frequency of MYD88 L265P mutation in WM. Although the genetic background is not fully deciphered in WM, the role of NF-kB and JAK STAT pathways has been demonstrated in WM; which underlying mechanisms of deregulation remain to be elucidated. We aimed to analyze MYD88 mutation in exon 5 and to characterize the clinical significance of this genetic alteration in 67 WM. Method. 67 patients (42 males, 25 females) diagnosed with WM were included in this study, along with 9 patients with chronic lymphocytic leukemia (CLL), 4 multiple myeloma (MM) and 9 marginal zone lymphoma (MZL) were also studied. Patients were untreated at time of BM collection and gave informed consent prior to research sampling. Clinical features, immunophenotypic markers using flow cytometry (Matutes score panel, CD38, CD138, CD27, CD80), conventional cytogenetic, FISH and SNP array data (n = 46) were analysed. B cells from bone marrow and T cells from blood were isolated respectively using B cell isolation kit and Pan T isolation kit (Myltenyi Biotech). For DNA sequencing of exon 5 of MYD88, the exon 5 of MYD88 gene was amplified from genomic DNA by PCR. The purified PCR products were directly sequenced in both directions using BigDye® Terminator Cycle Sequencing Kit (Applied Biosystems, CA, USA) and analyzed on the Applied Biosystems 3130xl Genetic Analyzer. Data were analyzed with SeqScape software version 2.5 (Applied Biosystems). Results. MYD88 L265P mutation (MYDmut) was observed in 79% of patients, including homozygous mutation in two patients (3%). MYD88 mutation was not identified in T lymphocytes isolated from 4 WM patients that confirmed MYD88 mutation was acquired in the tumoral cells. We haven't observed any other mutation on exon 5. We then sought for other mechanisms of MYD88 gene alteration, such as copy number alteration (CNA) and copy neutral –loss of heterozygosity (CN-LOH) also considered as an acquired UPD (uniparental disomy) at MYD88 locus. We found an UPD at MYD88 locus in solely one patient (2%), and haven't identified any deletion at 3p22. On the contrary, we observed a gain on chromosome 3 at 3p22 locus (including MYD88 gene) in 7/57 (12%) patients. Taking together, we identified alteration of the MYD88 locus in 85% of patients with WM, by either gain-of-function mutation (79%) or CNA (12%). Interestingly, we found gain on chromosome 3 more frequently in the MYDwildgroup than in the MYDmutgroup (p=0.02). Twenty one percent of the patients with WM had no mutation of MYD (MYDwild), and were characterized with a female predominance, a splenomegaly, gain of chromosome 3 and CD27 expression. We did not observed difference in terms of survival according to the MYD88 mutation status. MYD88 mutation was not related to deletion 6q, gain of 4, deletion 11q, deletion 17p, deletion 13q14 in our study. Interestingly, deletion 7q, a frequent cytogenetic aberration in marginal zone lymphoma, was rare in our series (4/57; 7%) and was independent of MYD88 mutation status (2 in the MYDwild and 2 in the MYDmut) (p=ns). No MYD88 L265P mutation was observed in CLL and MM. In MZL, 1/9 patient without M monoclonal component had a MYDL265p mutation. Conclusion. These results confirm a high frequency of MYD88 L265P mutation in WM that may become a useful biomarker for diagnostic in WM and may help better understand the physiopathogeny of WM. Disclosures: No relevant conflicts of interest to declare.