Abstract: Three different scoring systems have been developed to assess pre‐transplant comorbidity in allogeneic hematopoietic stem cell transplantation (Allo‐HSCT): the Hematopoietic Cell Transplantation‐Specific Comorbidity Index, the Comorbidity/Age index, and the Augmented Comorbidity/Age index. All were devised to predict overall survival (OS) and disease‐free survival (DFS) survivals and non‐relapse mortality (NRM) in patients receiving HLA‐matched Allo‐HSCT, but their performance has scarcely been studied in the haploidentical Allo‐HSCT setting with post‐transplant cyclophosphamide, a procedure in constant expansion worldwide. Methods To address this issue, their impact on survivals and NRM was examined in a cohort of 223 patients treated with haploidentical Allo‐HSCT in four different centers. Results With a median follow‐up of 35.6 months, 3‐year OS, DFS, and NRM were 48.1% ± 4%, 46.3% ± 4%, and 30.0% ± 3%, respectively. No impact was found for any of the three comorbidity scores in univariate analysis. In multivariate analyses, the only three factors associated with lower OS were DRI ( p   〈  0.001), an older age of recipients (≥55 years old, p  = 0.02) and of donors (≥40 years old, p  = 0.005). Older donor age was also associated with lower DFS and higher NRM. Conclusion The comorbidity scores do not predict survivals nor NRM in haploidentical Allo‐HSCT with PTCY, suggesting that pre‐transplant comorbidities should not be a contra‐indication to this procedure.

Abstract: Introduction: Pre-transplant comorbidities, which may impact the success of allogeneic stem cell transplantation (AlloSCT) can be appreciated through 3 different scoring systems. The Hematopoietic Cell Transplantation-Specific Comorbidity Index (HCT-CI) allows to predict non-relapse mortality (NRM) and survival (Sorror, Blood 2005). Its prognostic value was further augmented by the addition of donor age ( & lt; vs ≥40 yo) (Comorbidity/Age index, C/AI, Sorror, JCO 2014) then of pre-transplant ferritin ( & lt; or & gt;2500 µg/L) and albumin ( & lt;3 g/dL vs 3-3.5 g/dL vs & gt;3.5g/dL) serum levels as well as platelet count ( & lt; vs & gt;100 109/L) (Augmented Comorbidity/Age index, AC/AI, Elsawy, BBMT 2019). The performance of these 3 scores has not been evaluated in haploASCT using post-transplant cyclophosphamide (PTCY), a procedure in constant expansion worldwide. Material and Methods: We studied retrospectively the impact on non-relapse mortality (NRM), overall (OS) and disease-free (DFS) survival of the 3 comorbidity scores on a cohort of 223 patients (pts) having received a haploSCT with PTCY. All pts had pre-transplant ferritin and albumin levels and platelet counts available. These parameters were evaluated at the time of the pre-transplant check-up or just before conditioning (median from transplant: 20 days, range: 4-49). Results: Pts were recruited in 4 French centers (Nantes n=127; Angers n=45; Besançon n=29, Brest n=22). They had received haploSCT between October 2013 and January 2020. There were 136 males and 87 females with a median age of 55 yo (16-71, & gt;40 years n=172). The majority of pts had a myeloid disease (n=157) and received a reduced intensity regimen (n=161, myeloablative n=30; sequential n=32). Respectively, 132 and 91 pts had low/intermediate and high/very-high Disease-Risk Index (DRI). All pts received PTCY, cyclosporine and mycophenolate mofetyl as graft versus host disease (GVHD) prophylaxis. Donors had a median age of 40.8 years (19.4-71.7). Median HCT-CI, C/AI and AC/AI scores were 2 (0-8), 3 (0-9) and 3 (0-11), respectively. The HCT-CI score was & lt;2 in 139 patients, CA/I was & lt;3, 3-4 and & gt;5 in 110, 83 and 30 pts, respectively, while the AC/AI score was & lt;4 in 112 cases. With a median follow-up for alive patients of 35.6 months (6-77), 3-year OS, DFS and NRM were 47.8+3%, 46+3% and 29.4+6%, respectively. In univariate analysis, better 3-year OS and DFS were associated with lymphoid diseases (OS: 60.4+6% vs 42.3+4%, p=0.02; DFS: 56.2+6% vs 41.6+4%, p=0.04), low/intermediate DRI (OS: 59.1+4% vs 30.1+7%, p & lt;0.001; DFS: 56.3+4% vs 31.1+5% p & lt;0.001), donor age & lt;40 years (OS: 58.1+4% vs 36.2+5% p=0.004; DFS: 55.4+4% vs 35.7+4% p=0.01), and albumin level ( & lt;3g/dL OS: 33.3+12% vs 3-3.5g/dL 46.1+8% vs & gt;3.5g/dL 50.1+4%, p=0.03; & lt;3g/dL DFS: 30+12% vs 3-3.5g/dL 44.5+8% vs & gt;3.5g/dL 47.4+3%, p=0.05). OS and DFS were not impacted by ferritin levels, platelet count, recipient age, gender, nor any of the 3 comorbidity scores. A lower 3-year NRM was observed in younger pts ( & lt;55 yo) (21.8% vs 36.8%, p=0.02) and in those with a younger donor ( & lt;40 yo) (20.5% vs 39.2%, p=0.003). NRM was not associated with gender, type of disease, DRI, ferritin, albumin, platelet counts nor any of the 3 comorbidity scores. In multivariate analysis, each comorbidity score was compared to DRI, donor and patient age, type of disease and pre-transplant albumin levels. DRI and donor age remained associated with OS and DFS. This was also the case for recipient age, except when considering a high C/AI index score. Finally, an older age of recipients and donors remained associated with higher NRM. Conclusion: HCT-CI, C/AI and AC/AI do not to predict survivals nor NRM in haploSCT with PTCY, suggesting that pre-transplant comorbidities should not be a contra-indication to this procedure. As donor age is the only factor predicting survivals and NRM in this series, while multiple donors are generally available in the haploSCT setting, the selection of a younger donor should be the rule whenever possible for all patients. Disclosures Hunault: Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Diachi: Membership on an entity's Board of Directors or advisory committees; Jansen: Honoraria; Servier: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees. Deconinck:ImmunoGen: Consultancy, Research Funding; Stemline: Consultancy. Thepot:astellas: Honoraria; novartis: Honoraria; sanofi: Honoraria; celgene: Honoraria. Le Gouill:Loxo Oncology at Lilly: Consultancy; Roche Genentech, Janssen-Cilag and Abbvie, Celgene, Jazz pharmaceutical, Gilead-kite, Loxo, Daiichi-Sankyo and Servier: Honoraria. Chevallier:Incyte Corporation: Honoraria.

Abstract: Introduction Failure to respond to steroid therapy for intestinal acute graft-versus-host disease (aGvHD) is associated with limited further therapeutic options. Fecal microbiotherapy is defined as the perfusion of treated stool from one or several healthy donors via the upper or lower gastrointestinal (GI) route aiming at improving microbial diversity and functionality. Here we report clinical outcomes from a 76-patient cohort with steroid refractory (SR) GI-aGvHD treated with the pooled allogenic fecal microbiotherapeutic MaaT013. Twenty-four patients were treated in the prospective, single-arm, phase IIa, HERACLES study (NCT03359980) while 52 patients were treated in an expanded access program (EAP). Patients and methods For HERACLES, 24 patients with grade III-IV SR-GI-aGvHD were treated with MaaT013 in 26 European sites, as a 2 nd line therapy after SR diagnosis and evaluable for treatment response. In EAP, 52 patients with steroid-dependent or SR-GI-aGvHD (classical n=41, late onset n=3, overlap syndrome n=8) were treated. These patients had previously received and failed 1 to 6 lines (median 3; 40/52 received ruxolitinib) of GvHD systemic treatments. GI-GvHD response was evaluated weekly and 28 days after day (D) 0 (inclusion for HERACLES or 1st dose for EAP). For all patients, GI-overall response rate (ORR) at D28 was defined as the proportion of patients achieving complete response (CR), very good partial response (VGPR) or partial response (PR), compared to D0, without the use of additional systemic therapy. Other endpoints included the best overall response (BOR) achieved at any time, and overall survival (OS). Prepared under GMP, MaaT013 is characterized by a highly consistent richness of 455 ±3% OTUs and an Inverse Simpson index & gt; 20. Treatment comprised 3 MaaT013 doses, each composed of 30 g of feces in 150 mL volume of inoculum (total 90 g of feces from 4 to 8 healthy donors) administered by enema (except for 2 EAP patients by nasogastric tube). All patients received at least 1 MaaT013 dose, 92% (HERACLES) and 87% (EAP) at least 2 doses, and 50% (HERACLES) and 71% (EAP) the full treatment course. In HERACLES, the reasons for not applying the 3 rd dose were death (n=5), physician decision to introduce salvage therapy (n=5), and ICU hospitalization (n=2)). Results In HERACLES, the GI-ORR was 38% including 5 CR, 2 VGPR and 2 PR. In EAP, positive GI-response was achieved in 31/52 patients (60% with 16 CR, 11 VGPR and 4 PR). Considering the GI-BOR, 13/24 (54%) and 35/52 (67%) achieved at least a PR in HERACLES and EAP respectively. In HERACLES, OS was 29% at month (M) 6 and 25% at M12. OS was significantly higher in responding (R) patients (achieving at least PR at D28) compared to non-responding (NR) (44% vs 20% at M6 and 44% vs 13% at M12, logrank p=0.047). In EAP, OS was 48% at M6 and 37% at M12, and significantly higher in R patients compared to NR (71% vs 17% at M6 and 62% vs 6% at M12, logrank p & lt;0.0001). In HERACLES, treatment with MaaT013 was characterized by excellent tolerance: 252 Treatment-Emergent Adverse Events (TEAE) were reported for the 24 patients, the majority being infections (79%) and GI disorders (62%), as expected in GvHD patients. Of these 252 TEAE, only 2% (5 serious events in 2 patients) could not reasonably be excluded from being related to MaaT013 by the investigators. Shotgun sequencing in these 5 TEAE revealed that the causative infectious agents could not be detected in the administered MaaT013. In EAP, the safety profile of MaaT013 was considered satisfactory for all patients. 16S microbiome analyses were performed in the HERACLES population and showed that MaaT013 produced an early increase in α-diversity at genus level with a significant increase in Richness index at all evaluated timepoints (p & lt;0.003). At D28, R patients had higher values of α-diversity indices (Shannon p=0.005 and Richness p=0.038) compared to NR patients, and higher proportions of MaaT013-derived species in the total composition of R microbiota (p=0.043). Conclusion We herein report the treatment of 76 SR-GI-aGvHD patients using a full ecosystem, pooled-donor, high-richness biotherapeutic. The D28 GI-ORR was 38% and 60% in HERACLES and EAP respectively and this clinical benefit positively and significantly impacted OS (44% and 62% M12 in HERACLES and EAP R patients respectively). MaaT013 was shown to be safe and effective in these heavily immunocompromised patients, warranting further exploration of this approach. Figure 1 Figure 1. Disclosures Malard: JAZZ pharmaceuticals: Honoraria; Sanofi: Honoraria; Astellas: Honoraria; Biocodex: Honoraria; Therakos/Mallinckrodt: Honoraria; Janssen: Honoraria. Loschi: CELGENE/BMS: Honoraria; AbbVie: Ended employment in the past 24 months, Honoraria; Gilead: Ended employment in the past 24 months, Honoraria; Novartis: Ended employment in the past 24 months, Honoraria; Servier: Ended employment in the past 24 months, Honoraria; MSD: Honoraria. Cluzeau: Agios: Honoraria; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel, accommodations, expenses, Speakers Bureau; Roche: Consultancy, Honoraria; BMS/Celgene: Consultancy, Honoraria, Speakers Bureau; Jazz Pharma: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria, Speakers Bureau; Amgen: Speakers Bureau; Pfizer: Other: travel, accommodations, expenses; Astellas: Speakers Bureau; Takeda: Other: travel, accommodations, expenses. Huynh: Jazz Pharmaceuticals: Honoraria. Holler: MaaT Pharma: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees. Vehreschild: SocraTec R & D GmbH: Consultancy, Speakers Bureau; Pfizer: Consultancy, Speakers Bureau; Ferring: Consultancy, Speakers Bureau; Farmak International Holding GmbH: Consultancy, Honoraria, Speakers Bureau; Bio-Mérieux: Consultancy, Speakers Bureau; Basilea: Consultancy, Speakers Bureau; Arderypharm: Consultancy, Speakers Bureau; Alb Fils Kliniken GmbH: Consultancy, Speakers Bureau; Takeda Pharmaceutical: Research Funding; Seres Therapeutics: Research Funding; Roche: Consultancy, Research Funding, Speakers Bureau; Organobalance: Consultancy, Research Funding, Speakers Bureau; Merck/MSD: Consultancy, Research Funding, Speakers Bureau; MaaT Pharma: Consultancy, Research Funding; Immunic AG: Consultancy, Research Funding, Speakers Bureau; Glycom: Research Funding; Gilead Sciences: Consultancy, Research Funding, Speakers Bureau; Evonik: Research Funding; Da Volterra: Consultancy, Research Funding, Speakers Bureau; Biontech: Research Funding; Astellas Pharma: Consultancy, Research Funding, Speakers Bureau; 3M: Research Funding. Gasc: MaaT Pharma: Current Employment. Plantamura: MaaT Pharma: Current Employment. Mohty: Sanofi: Honoraria, Research Funding; Pfizer: Honoraria; Novartis: Honoraria; Takeda: Honoraria; Jazz: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Gilead: Honoraria; Celgene: Honoraria, Research Funding; Bristol Myers Squibb: Honoraria; Astellas: Honoraria; Amgen: Honoraria; Adaptive Biotechnologies: Honoraria.

Abstract: Prognosis of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph1+ ALL) has been considerably improved since the beginning of the BCR-ABL1 tyrosine kinase inhibitors (TKI) era 20 years ago. However, the prognosis of patients with a refractory/relapsed (including molecular relapse) disease is still very dismal. New drugs or combination of new drugs may improve outcomes of these patients. For example, ponatinib, a 3rd-generation oral TKI, known to have activity against BCR-ABL1 T315I mutations, has shown some efficacy in this context. Similarly, a recent study has reported very encouraging results of the bispecific anti-CD3/CD19 monoclonal antibody blinatumomab as single-agent in refractory/relapsed Ph1+ ALL. Data regarding the efficacy and tolerance of a combination of blinatumomab+ponatinib (blina/pona) are still scarce. This was a retrospective study with the aim to report outcomes of patients receiving a combination of blina/pona for refractory/relapsed Ph1+ ALL in France. Fifteen adults from 8 French centers were identified and data were collected by physicians of each centers, then gathered for the purpose of this study. There were 9 males and 6 females, with a median age of 53 years (range:17-72). All patients, but 2 with blast crisis of chronic myeloid leukemia, had de novo Ph1+ ALL. Four cases had BCR-ABL1 T315I mutation. Patients received the blina/pona combination, either after a first (n=8) or a second (n=7) cytologic relapse. There was no refractory patient in theses series. Previous allograft and autograft has been performed in 7 and 2 patients, respectively. The majority of patients (n=12) had previously received 2 or more lines of TKI. The median time between the first cycle of blina/pona and diagnosis was 14 months (range: 8-40). The median number of blinatumomab cycle (28 mg/day by continuous infusion for 28 days every 6 weeks) administered per patient was 3 (range: 1-6) while ponatinib was concomittantly administered continuously at an initial dose of 45 mg once daily in 11 pts (73%) and 30 mg in 4 pts (27%). Median duration of ponatinib administration was 4 months (range: 1.1-10.9) from first blinatumomab cycle. The toxicity profile was safe: all patients received a complete first cycle without grade 3-4 adverse events. After cycle 1, blinatumomab was stopped in 47% of cases because of neurologic events in 4 and infections in 3; ponatinib was stopped in 33% of cases because of neurologic events in 3, fluid retention in 1 and severe arteriopathy in 1 patient with other vascular disease risk factors. All neurologic events resolved after stopping blinatumomab or ponatinib. The majority of patients were evaluated after one cycle (n=11, after cycle 2 n=3, after cycle 3 n=1). All but one patients (93%) obtained a cytologic complete remission (CR), of whom 12/14 (86%) achieved a complete molecular response. However, 2 patients were documented with CNS relapse at the time of blina/pona evaluation although in bone marrow molecular remission. Both obtained clearance of leukemic blasts after intrathecal infusion of chemotherapy. Then, 5 patients underwent allogeneic transplant (including 2 patients already allotransplanted before blina/pona) and 1 patient received donor lymphocyte infusion. Seven cases pursued maintenance therapy with ponatinib as single agent after stopping blinatumomab. With a median follow-up of 8 months (range: 2.6-30.2) for alive patients, median overall and leukemia-free survivals from first cycle of blina/pona were 8.5 months (range: 1.7-30.2) and 8 months (range: 1.3-30.2), respectively. At last follow-up (July 2018), only 4 relapses had occurred at a median of 3.3 months (range: 1.3-8.3) from first blina/pona cycle and 6 patients had died (3 bacterial infections, 1 fungal infection, 1 secondary cancer and 1 ALL relapse). All alive patients (n=9) but one (cytologic CR but detectable minimal residual disease) are in complete molecular response. Four patients are still under ponatinib medication at last follow-up. The combination of blinatumomab+ponatinib appears effective and tolerable in relapsed Ph1+ALL patients and may replace chemotherapy salvage regimens. The combination should be tested in first-line therapy in the future. Our results have also to be confirmed prospectively on a larger cohort of patients. Disclosures No relevant conflicts of interest to declare.

Abstract: Central nervous system (CNS) thrombotic events are a well‐known complication of acute lymphoblastic leukemia (ALL) induction therapy, especially with treatments including l ‐asparaginase ( l ‐ASP). Data on risk factors and clinical evolution is still lacking in adult patients. We report on the clinical evolution of 22 CNS venous thrombosis cases occurring in 708 adults treated for ALL or lymphoblastic lymphoma (LL) with the Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)‐induction protocol, which included eight L‐ASP (6,000 IU/m 2 ) infusions. The prevalence of CNS thrombosis was 3.1%. CNS thrombosis occurred after a median of 18 days (range: 11–31) when patients had received a median of three l ‐ASP injections (range: 2–7). Patients with CNS thrombosis exhibited a median antithrombin (AT) nadir of 47.5% (range: 36–67%) at Day 17 (range: D3–D28), and 95% of them exhibited AT levels lower than 60%. There were no evident increase in hereditary thrombotic risk factors prevalence, and thrombosis occurred despite heparin prophylaxis which was performed in 90% of patients. Acquired AT deficiency was frequently detected in patients with l ‐ASP‐based therapy, and patients with CNS thrombosis received AT prophylaxis (45%) less frequently than patients without CNS thrombosis (83%), P = 0.0002). CNS thrombosis was lethal in 5% of patients, while 20% had persistent sequelae. One patient received all planned l ‐ASP infusions without recurrence of CNS thrombotic whereas l ‐ASP injections were discontinued in 20 patients during the management of thrombosis without a significant impact on overall survival ( P = 0.4). Am. J. Hematol. 90:986–991, 2015. © 2015 Wiley Periodicals, Inc.