Abstract: Abstract 2971 Introduction: Bendamustine is a bifunctional alkylating agent approved for the treatment of several lymphoproliferative disorders. Studies have evidenced its efficacy in multiple myeloma (MM), but data so far available in this setting are scarce. We performed a retrospective analysis of Italian patients with relapsed/refractory MM, who had received bendamustine as salvage therapy within a national compassionate use program. Patients and methods: Seventy-eight patients (42 males, 36 females) were collected in 19 hematological centers. Mean age was 64.2 years (range 38–84). ISS was equally distributed, with about one third of patents being represented in single stages. Twenty-three of 43 analyzed patients had cytogenetic abnormalities, the most frequent being del13q (14 patients); t(4;14) and t(11;14) were observed in 4 and 2 patients, respectively, while t(6;14), del17p or complex karyotype occurred in single patients. The median number of prior lines of therapy was 4 (range 1–10). Ninety-seven percent of patients had previously received bortezomib, 94% IMIDs, 85% melphalan, 74% cyclophosphamide, 45% anthracyclines, 26% other drugs, 33% radiotherapy. Sixty percent of patients had undergone autologous and 4% allogeneic stem cell transplantation. The last treatment before bendamustine was a bortezomib-based regimen in 31%, an IMIDs-based regimen in 42%, a combined bortezomib/IMIDs-based regimen in 9%, while 18% of patients had received other therapies. Seventy-three percent of patients were resistant to last therapy received, while 27% had relapsed. Median duration of response to last treatment received before bendamustine was 9 months (range 2–46). Median Hb value was 10.1 g/dl (range 7.6–14.9), WBC count 2.700/μl (range 550–15.200), PLT count 130.000/μl (range 6.000–410.000). Serum creatinine, calcium, beta2-microglobulin and LDH levels were increased in 12 (15%), 4 (5%), and 44 (56%) patients, respectively, while albumin levels were decreased in 27 patients (35%). The median percentage of marrow plasma cells (as evaluated in 57 cases) was 60% (range 1–100). Seventy-six percent of patients had osteolytic bone involvement and 78% extramedullary localizations, with 13% showing secondary plasma cell leukemia and 7% documented amyloidosis or proteinuria. Finally, 45% of patients presented with at least one severe comorbidity, mainly cardio-vascular, liver or pulmonary dysfunction, and diabetes. Results: A total of 236 cycles was administered (median 3, range 1–9). In 47% of patients bendamustine was variously associated to bortezomib (23%), or IMIDs (21%), or to a combination of both (3%). In 80% of patients receiving bendamustine +/− steroids, a median dose of 90 mg/sqm for two consecutive days every 28 days was employed; the median dose was 80 mg/sqm when bendamustine was combined with bortezomib, 60 mg/sqm with IMIDs (total range: 40–140 mg/sqm). The remaining patients received single, monthly doses ranging from 60 to 150 mg/sqm. According to IMWG uniform response criteria, 21 out of 73 evaluable patients achieved a response after a median time of 3 months. In particular, there were 16 PR, 1 VGPR, 1 sCR, and 3 CR; overall response rate (ORR) was, therefore, 29%. Response rate was 10% (4/39) in bendamustine single agent +/− steroids, 38% (5/13) in bendamustine + bortezomib and 62% (10/16) in bendamustine + IMIDs subgroups, respectively. Responders had received a lower number of previous treatments than non responders (median 3 vs 4). Response rate was higher in relapsed (12/21, 57%) than in resistant patients (10/57, 17%). The time to best response ranged from 1 to 8 months. After a median follow-up of 8 months, median PFS duration was 6 months, with 13 out of 21 responding patients not yet progressed. Median OS of the entire cohort was 6.2 months (7 months in responders and 4 months in non responders, range 0–27). Grade 3–4 hematological and non-hematological toxicities occurred in 56% and 15% of patients, respectively, causing three interruptions of the treatment. Conclusions: Though with the clear limits due to the high heterogeneity of treatments applied and of population analyzed, our data indicate that bendamustine may be a therapeutic option in heavily pretreated MM, suggesting a possible non cross-resistance with other agents. Its earlier use with appropriate doses and combinations might further improve the results obtained in this study. Disclosures: Musto: Mundipharma: Honoraria. Off Label Use: Bendamustine in relapsed/refractory myeloma. Fragasso:Mundipharma: Honoraria. Baldini:Mundipharma: Honoraria. Storti:Mundipharma: Honoraria.

Abstract: Introduction: Patients with refractory and relapsed B-cell lymphomas have few curative options. Despite novel target therapies, only patients receiving allogeneic stem cell transplantation (alloSCT) can achieve a long-term disease control. A lot of effort has been done over the last years to produce strategies reducing non-relapse mortality (NRM) without damaging the graft-versus-lymphoma effect. We conducted a multicenter prospective phase II trial to evaluate the benefit of high-dose Rituximab (R) in the conditioning regimen before alloSCT. The primary end-point of the study was progression-free (PFS) survival. We evaluated also the long-term outcome with the novel composite end-point of graft-versus-host disease-free/relapse-free survival (GRFS). Methods:The study enrolled 121 adult patients who received alloSCT for relapsed/refractory B-cell lymphomas [n=35 (28%) follicular lymphomas; n=29 (24%) chronic-lymphocytic leukemia; n=35 (28%) diffuse large B-cell lymphomas; n= 22 (18%) mantle cell lymphomas] . The median age was 52 years (range, 23-65). Seventy-four pts (61%) failed a previous autograft. The conditioning regimen consisted of thiotepa (12 mg/kg), cyclophosphamide (60 mg/kg) and fludarabine (60 mg/m2) and high-dose of rituximab (500 mg/m2 on day-6),. Graft-versus-host disease (GVHD) prophylaxis was based on cyclosporine and mini-methotrexate; ATG (7 mg/kg) was given to the patients allografted from unrelated donors. Sixty-seven (55%) and fifty-four (45%) patients received grafts from related and unrelated donors, respectively. Results: At a median follow-up of 41 months (range 6-95 months), the estimated 3-years PFS and overall survival (OS) were 50% (95%CI, 41%-61%) and 61% (95%CI, 51%-71%), respectively. The 1 and 3-years GRFS were 40% (95%CI, 32%-50%) and 34% (95%CI, 26%-44%), respectively. The GRFS was significantly better in patients affected by indolent disease (43% versus 22%, long-rank test, p=0.02); in addition there was a tendency for better GRFS for those transplanted from unrelated donors (41% versus 27%, p=0.096). The 3-years GRFS were 41% and 30% in patients with complete remission (CR) and partial remission (PR) at the time of transplant, respectively (p=0.185). The multivariate analysis showed that patients affected by aggressive histotype and with bone marrow (BM) infiltration at time of transplant had a poor outcome in terms of PFS, OS and GRFS [hystotype: PFS, HR 3.30 (p=0.003); OS, HR 3.73 (p=0.007); GRFS, HR 2.02 (p=0.026); BM infiltration: PFS, HR 4.79 (p 〈 0.001); OS, HR 6.00 (p 〈 0.001); GRFS, HR 2.7 (p=0.004)]. The crude cumulative incidence (CCI) of NRM was 21% (95%CI, 14%-30%) at 3-years whereas the CCI of acute GVHD grade II-IV was 22% (95%CI,15%-30%). The CCI of acute GVHD was not statistically significant different in matched sibling donors and unrelated donors (21% versus 22%, respectively p=0.717). According to the modified Seattle criteria, the CCI of extensive GVHD was 17% (95%CI, 11%-27%) whereas the limited form was 27% (95%CI, 19%-39%). In the univariable Fine and Gray model, the only factor that was protective against the occurrence of chronic GVHD was the transplant from unrelated donors when R and ATG were combined together [HR 0.50 (95%CI, 0.25-0.99), p=0.05] . In fact, the CCI of chronic GVHD at 3-years from matched sibling donors was 54% (95%CI,42%-71%) as opposed to 31% from unrelated donors (95%CI, 19%-49%) (p=0.04). Conclusions: Our trial showed:1) R did not improve PFS as compared with our historical control; 2) the combination of R and ATG is synergistic and resulted protective against chronic GVHD; 3) GRFS analysis showed that 34% of the patients are alive without any complications at 3-years after allograft and this should be the standard to compare novel drug results. Future protocols should consider the use of GRFS as endpoint and inclusion of ATG also for those receiving sibling grafts. Disclosures Cascavilla: Janssen-Cilag: Honoraria.

Abstract: Introduction Coronavirus Disease 2019 (COVID19) has shown higher mortality in patients with comorbidities, including cancer. First reports from China, Italy, and US showed mortality comprised between 20% and 40% in this specific population. However, the number of patients in these studies was limited and the percentage of hematological patients was underrepresented. In our study, we present a prospective evaluation of patients affected by solid and liquid tumors who were affected by COVID19 from the same geographical area and time period. Survival outcomes, prognostic risk factors, and effects of oncological treatments received were analyzed. Methods WAll consecutive oncological patients with age & gt; 18 years old affected by COVID19 (confirmed by pharyngeal PCR test) who were hospitalized in 5 tertiary oncological referral centers in the Catalonia region were included in the study. The recruitment period started from 13/03/2020 to 24/04/2020. Two-hundred thirty-one patients were recruited. Thirty-three percent had hematological malignancies and 67% had solid tumors. The median age was 65 years (range 58-75 years). Female patients were 41%. Twenty-six percent of patients were not considered candidates to intensive care treatments (tracheal intubation) due to their advanced oncological status. Of the hematological cohort, lymphoid malignancies represented 36% of the population, multiple myeloma 20%; acute leukemias 15%; chronic lymphoproliferative diseases 12% and other malignancies 17%. At the time of infection, 11% of patients were receiving steroids (more than 0.5mg/kg/24 hours & gt;15 days), 4% were on active immunosuppressive therapy (calcineurin inhibitors, sirolimus or mycophenolate mofetil) and 5% had grade & gt;3 neutropenia. Most importantly, 61% were on active oncological treatment, 18% were on follow-up, 10% had been diagnosed without having received any treatment. Results At COVID19 diagnosis, 75% of patients had a fraction of inspired oxygen (FiO2) & lt; 24% and 63% had fever. Only 16% had cough,16 % had mucous secretion and 12% had dyspnea. All the other symptoms (myalgia, diarrhea, anosmia, ageusia, fatigue, headache) had an incidence & lt; 10%. Chest X-ray was abnormal in 60% of cases. Regarding in-hospital treatments, 85% received antibiotics, 76% hydroxychloroquine, 12% tocilizumab, 30% corticoids, 70% prophylactic anticoagulation and 55% oxygen support. The median duration of hospitalization was 9.00 days (range 5-16 days). WThe overall mortality rate was 26% with a non-significant difference between hematological (32%) and oncological (23%) patients (p-value = 0.23, figure 1). A significant difference was observed between patients who were candidates to intensive care treatments (21.5%) and not candidates (42.6%)(p-value = 0.0038, figure 1). The following risk factors were associated with decreased survival on multivariate analysis: having the oncological disease in progression (HR 3.33, 95%Confidence Interval (CI)= 1.73-6-41, p & lt;0.001); use of steroids ( & gt;0.5mg/kg/24 hours) in the last 15 days (HR 3.76; 95%CI=1.69-8.40, p & lt;0.001); age (continuous variable, HR 1.05, 95%CI= 1.01-1-08, p=0.005); grade 4 neutropenia. When considering COVID19 in-hospital treatments, only steroids were associated with a protective effect on survival (HR 0.51, 95%CI=0.27-0.94, p=0.032) while hydroxychloroquine and tocilizumab had no significant effect. Severe respiratory insufficiency (defined as use of & gt;50% FiO2 as oxygen support) was present or developed in 46% of patients. On multivariate analysis, the following factors were associated with a higher risk of developing severe respiratory insufficiency: use of steroids ( & gt;0.5mg/kg/24 hours) in the last 15 days (HR 2.36; 95%CI=1.12-4.97, p=0.023); age (HR 1.05, 95%CI= 1.01-1-08, p=0.009) and dyspnea at diagnosis (HR 3.95; 95%CI=1.77-8.78, p=0.001). Conclusion WCOVID19 is associated to increased mortality in patients affected by solid and liquid tumors. Being a candidate for intensive care treatments could improve survival while having progressive disease, older age and grade & gt;3 neutropenia were considered negative factors. Interestingly, the use of steroids was associated to reduced survival if received within 15 days before COVID19 diagnosis, while it has protective effect when used as part of COVID19 therapy. Disclosures Mussetti: Novartis, Gilead: Honoraria, Research Funding. Sureda Balari:Gilead/Kite: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; BMS: Speakers Bureau; Roche: Honoraria; Sanofi: Consultancy, Honoraria; Merck Sharpe and Dohme: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Celgene/Bristol-Myers Squibb: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Speakers Bureau; Incyte: Consultancy. OffLabel Disclosure: Tocilizumab for COVID19

Abstract: Background The majority of relapses in HL occur within the first three years from end of first-line treatment. Late relapses, occurring after more than five years, are rare events and there is no consensus on the optimal treatment. Aims of study The aim of our retrospective analysis was to assess the proportion of relapses occuring 〉 5 years in patients enrolled on clinical trials at INT-MI between 1974 and 2007, to evaluate prognostic factors, treatment outcome and survival. Patients and Methods From 1974 to 2007, 1089 consecutive HL patients, previously untreated with chemotherapy (CT), were enrolled on clinical trials at the INT-MI; 959 patients in complete remission (CR) after first-line CT or combined modality treatment were included in this study. In all patients who relapsed 〉 5 years from end of frontline treatment a second biopsy was performed to prove HL histology at relapse. Failure-free survival (FFS) was calculated from the date of late relapse until documented relapse from CR after salvage therapy, disease progression during or within 3 months from end of salvage therapy, or death, whichever came first. Overall survival (OS) was calculated from the date of late relapse to last follow-up visit or death. Results A total of 31 complete responders after first-line therapy relapsed after 〉 5 years. Median time from end of first-line therapy to relapse was 115 months (range, 63-299). Main patient characteristics at late relapse were as follows: males: 71%; median age: 48 years (range, 20-67); classical histology: 81%; stage III/IV: 55%; B Symptoms: 48%; extranodal disease: 26%; 〉 3 involved sites: 52%; bulky disease: 13%; GHSG prognostic score ³ 1: 52%; MSKCC prognostic score ³ 1: 61%. Conventional dose salvage chemotherapy (CT) was delivered to 64.5% of patients: 9 patients were retreated with the same regimen employed as front-line therapy (MOPP alternated with ABVD), 5 were retreated with ABVD alone, 6 received non cross-resistant regimens. High-dose chemotherapy (HDCT) with hematopoietic stem cell reinfusion (ASCT) was delivered to 35.5% of patients. With a median follow-up of 9 years, 10-year FFS was 57% (95% Confidence Interval CI: 33-75) and OS was 64% (95% CI: 41-80). In univariate analysis only age 〉 48 years was associated with an inferior FFS [44 % (95% CI:18-68) vs 92% (95% CI:54-99), p= 〈 0.001] and OS [40% (95%CI:16-65) vs 100% , p=0.03] . There was no significant difference in the outcome of patients treated with HDCT+ASCT compared to those treated with conventional dose CT [FFS 75% (95%CI: 30-93) vs 63% (95%CI: 36-82), p=0.78; OS 71% (95%CI: 26-92) vs 64% (95%CI: 34-83),p=0.21]. Conclusions: This retrospective cohort of patients with late relapse HL is to date one of the largest case series and with the longest follow up. Besides the rarity of these cases, late relapse of HL appears to have a good prognosis. Classical prognostic scores for relapsed HL have no role in this setting. In the subgroup analyses, being older than 48 years conveys a worse prognosis. HDCT and ASCT does not appear to confer an important survival advantage over conventional dose CT. Figure 1. Figure 1. Disclosures Viviani: Takeda Italia SpA: Consultancy; Teva Italia SpA: Consultancy; Italfarmaco SpA: Consultancy; Takeda International: Consultancy. Corradini:Celgene: Consultancy; Novartis: Consultancy.

Abstract: Introduction: Axicabtagene ciloleucel (axi-cel) and tisagenlecleucel (tisa-cel) are the two autologous anti-CD19 chimeric antigen receptors T cells commercially approved in Europe for relapsed/refractory (R/R) DLBCL. We performed a retrospective study to evaluate patients characteristics, efficacy and safety for axi-cel and tisa-cel in a large cohort of patients within the GETH-TC (Spanish Group of Stem Transplantation and Cell Therapy)-GELTAMO (Spanish Group of Lymphoma and Autologous Stem Cell Transplantation). Methods: Ten Spanish centers contributed data. Data were collected retrospectively from consecutive patients with DLBCL in whom apheresis was performed for axi-cel or tisa-cel treatment. CRS and ICANS were graded with the ASTCT consensus criteria. Response was assessed according to the Lugano criteria. Patients included had at least 30 days of follow-up. Results: A total of 268 patients with R/R DLBCL underwent apheresis for axi-cel (n=123) and tisacel (n=145) from Nov-2018 to May-2021, of which 232 (86%) received CART-cell infusion (n=110, 89% and n=122, 84%, respectively). Reasons for not undergoing infusion were progression in 10 cases, tumor lysis syndrome in 1, infection in 1, and CR after bridging therapy in 1 for the axi-cel cohort, and progression in 21 (4 after manufacture failure), psychiatric disorder in 1, and post-apheresis cerebral hemorrhage in 1 case for the tisa-cel cohort. Time between apheresis and infusion was 41 days (IQR 40-56) and 49 days (IQR 46-62) (p=0.006), respectively. Characteristics at baseline, apheresis and at lymphodepletion are summarized in Tables 1 and 2. Median age was 60 (range 19-79), 61% of patients were male, most of them treated for DLBCL NOS (66%). There were no significant differences between patients intended to be treated with axi-cel and tisa-cel. 82% of the infused patients received bridging therapy. At apheresis and at lymphodepletion ECOG performance status score was 0-1 in 93% and 91%, and 7 and 32 patients were in response, respectively. The overall response rates (ORRs) at 1 month and 3 months were 65% and 56%, respectively, with 34% and 45% achieving a complete response (CR), respectively. In the intention-to-treat analysis, with a median follow-up of 9 months (IQR 5-15), EFS and OS at 9 months was 44% (95%CI 38-51)(Figure 1) and 59% (95%CI 53-66) with a median EFS and OS of 6 months and 11 months, respectively. At lymphodepletion, characteristics of infused patients and disease were not significantly different between axi-cel and tisa-cel cohorts. Rates of CRS, CRS grade 3-4, ICANS, ICANS grade 3-4 were 89% and 71% (p=0.001), 10% and 7% (p=0.34), 42% and 16% (p=0.001), 20% and 4% (p=0.001) for the axi-cel and tisa-cel cohorts, respectively. ICU admission was needed in 25% and 15% of patients (p=0.06), respectively. Non-relapse mortality at days 100 were 2.5% and 1.4%, and at day 180, 5.4% and 2.2% (p=0.08) for the axi-cel and tisa-cel groups, respectively. With a median follow-up of 8 months for patients who received infusion with axi-cel and 12 months for patients infused with tisa-cel, EFS and OS at 12 months were 48% and 33% (p=0.33), and 53% and 50% (p=0.27), respectively, with a median EFS of 11 and 6 months and a median OS of 13 and 12 months, respectively. In the multivariate analysis, the only factor associated with poor PFS was having ECOG-PS ≥2 at lymphodepletion (HR13, p=0.03). No factors were identified as associated independently to OS. Factors associated to CRS grade 3-4 were IPI score 4-5 at lymphodepletion (OR 1.4, p=0.03) and ECOG-PS ≥2 at apheresis (OR 1.5, p=0.03). For ICANS grade 3-4, factors associated were the use of axi-cel (OR 8, p=0.04) and diagnosis of HG double/triple hit lymphoma (OR 9, p=0.022). Conclusions:This multicentric analysis describes one of the largest real-life cohorts of patients treated with axi-cel and tisa-cel for R/R aggressive B cell lymphoma in Europe. Results are comparable to those from the pivotal studies and other large real-life experiences. Up to now, patients included for one or other product in Spain do not differ significantly in terms of baseline characteristics, and within this setting, results are comparable between both products in terms of efficacy. The use of axi-cel was associated to higher rates of CRS and especially, severe forms of ICANS. However, mortality associated to toxicity were low and not significantly different between both cohorts. Figure 1 Figure 1. Disclosures Kwon: Novartis, Celgene, Gilead, Pfizer: Consultancy, Honoraria. Iacoboni: BMS/Celgene, Gilead, Novartis, Janssen, Roche: Honoraria. Reguera: Janssen, Kite/Gilead, Novartis: Speakers Bureau; BMS-Celgene, Novartis: Membership on an entity's Board of Directors or advisory committees. Lopez Corral: Gilead, Novartis: Consultancy, Honoraria. Guerreiro: Novartis, Gilead: Consultancy, Honoraria. Caballero: Novartis, Gilead: Honoraria. Ortiz-Maldonado: Kite, Novartis, BMS, Janssen: Honoraria. Sanchez: Janssen, Jazz Pharmaceuticals, Gilead, Novartis, Amgen: Consultancy. Sancho: Roche, Janssen, Celgene-BMS, Gilead, Novartis, Takeda: Honoraria, Speakers Bureau; Roche, Janssen, Celgene-BMS, Gilead, Novartis, Incyte, Beigene: Speakers Bureau. Bastos-Oreiro: Janssen: Honoraria, Speakers Bureau; F. Hoffmann-La Roche: Honoraria, Research Funding, Speakers Bureau; Takeda: Speakers Bureau; Novartis: Honoraria, Speakers Bureau; BMS-Celgene: Honoraria, Speakers Bureau; Gilead: Honoraria; Kite: Speakers Bureau. Oarbeascoa: Gilead: Honoraria, Speakers Bureau. Mussetti: Gilead: Other: Unspecified, Research Funding; Novartis: Honoraria, Other: Unspecified; Takeda: Honoraria. Bailen: Gilead, Pfizer: Speakers Bureau. Martin Garcia-Sancho: Takeda: Honoraria; Novartis: Consultancy; Incyte: Consultancy; Celgene/BMS: Consultancy; Celgene: Honoraria, Other: travel; Roche: Consultancy, Honoraria, Other: Travel/Accommodations/Expenses; Janssen: Honoraria, Research Funding; Servier: Consultancy, Honoraria, Other: Travel/Accommodations/Expenses; Gilead: Consultancy, Honoraria; Morphosys: Consultancy; Kyowa Kirin: Consultancy; Clinigen: Consultancy; Eusa Pharma: Consultancy; Kern Pharma: Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company). Barba: Amgen, Celgene, Gilead, Incyte, Jazz Pharmaceuticals, MSD, Novartis, Pfizer and Roche, Jazz Phar,aceuticals: Honoraria; Cqrlos III heqlth Institute, aSOCIACION espanola contra el cancer, PERIS: Research Funding.

Abstract: Backgrounds: Allogeneic Hematopoietic Cell Transplantation (HCT) is a potentially curative treatment for fit patients with relapsed/refractory multiple myeloma (MM). When a HLA-identical donor is not available, haploidentical HCT (haploHCT) represents an acceptable therapeutic option, especially when post-transplant cyclophosphamide (PT-Cy) is used as anti-GVHD prophylaxis. Patients and methods: Twenty-nine patients (median age 56 years, range 47-70) undergoing myeloablative (n=15) or reduced-intensity (n=14) haploHCT from February 2011 to November 2015 are included in this retrospective analysis. The median number of previous lines of therapy was 2 (range 1-7) with 27 (93%) of patients having previously performed an autologous HCT. Both bortezomib and lenalidomide were used in 27 (92%) patients before haploHCT. Eighteen patients (62%) had chemosensitive disease at time of haploHCT (CR=4, VGPR=9, PR=5) and 11 (38%) had chemorefractory disease (PD=7, SD=4). Graft source was marrow-derived in 59% (n=17) and peripheral blood in 41% (n=12) of patients. Standard post-transplant cyclophosphamide anti-GVHD prophylaxis (50mg/mq day +3 and +4 or +5) plus mycophenolate and cyclosporine (n=24) or tacrolimus (n=3) or rapamycine (n=2) was used for the whole study cohort. Overall survival (OS) and Progression Free Survival (PFS) were performed with Kaplan-Meier analysis. Neutrophil and platelets engraftment, acute GVHD, chronic GVHD, Non-Relapse-Mortality (NRM) and Relapse Incidence/Progression of Disease (RI/POD) were obtained with competing risk analysis. Results: At day +30, neutrophil and platelets engraftments were 86% (95%CI:65-95) and 59% (95%CI:38-74), respectively. Acute GVHD grade 〉 2 at days +100 and +180 were 38% (95%CI: 20-55%) and 41% (95%CI: 23-59%), respectively. All grade chronic GVHD at 12 and 18 months was 21% (95%CI: 8-37. At 18 months, RI/POD was 39% (95%CI:20-58%) and NRM 15% (CI95%:5-32). With a median follow-up in survivors of 16 months (range 5-55 months), the 18-month OS and PFS were 68% (95%CI: 47-82%) and 34% (95%CI: 15-54%), respectively. Chemorefractory disease at transplant was associated with a worse 18-month RI/POD (70% vs 18%, p= 〈 0.01) and a markedly reduced PFS (9% vs 57%, p=0.04) and OS (53% vs 78%, p= 〈 0.01) (Figure 1). Survival outcomes were similar between marrow-derived and peripheral blood graft source cohorts. Conclusions: HaploHCT is a feasible and effective strategy in patients with relapsed/refractory high-risk multiple myeloma. Chemorefractory disease at transplant was the only prognostic factor associated with a significant reduced RI/POD, PFS and OS. Figure Kaplan-Meier estimates of progression free survival from time of transplant of the chemosensitive and chemorefractory disease. Figure. Kaplan-Meier estimates of progression free survival from time of transplant of the chemosensitive and chemorefractory disease. Disclosures No relevant conflicts of interest to declare.

Abstract: The Endothelial Activation and Stress Index (EASIX) is a laboratory-based prognosis index defined as creatinine × lactate dehydrogenase/platelets. When measured at pretransplantation evaluation (EASIX-PRE), it predicts allogeneic hematopoietic cell transplantation (alloHCT) mortality. This study explores its ability to predict intensive care unit (ICU) admission and validates EASIX-PRE predictive power for overall survival (OS) and nonrelapse mortality (NRM) in 167 consecutive patients undergoing alloHCT. EASIX-PRE was calculated retrospectively in all patients and transformed into log2 values (log2-EASIX-PRE). Log2-EASIX-PRE predicted ICU admission (hazard ratio [HR], 1.41; P & lt; .001), OS (HR, 1.19; P = .011), and NRM (HR, 1.28; P = .004). The most discriminating EASIX-PRE cutoff value for risk of ICU admission was the 75th percentile (2.795); for OS and NRM, it was the median value (1.703). Patients with EASIX-PRE & gt;2.795 had higher incidence of ICU admission in comparison with patients with lower EASIX-PRE values (day +180, 35.8% vs 12.8%; HR, 2.28; P = .010). Additionally, patients with EASIX-PRE & gt;1.073 had lower OS (2 years, 57.7% vs 68.7%; HR, 1.98; P = .006) and higher NRM (2 years, 38.7% vs 18.5%; HR, 2.92; P = .001) than patients with lower EASIX-PRE results. Log2-EASIX-PRE was not associated with incidence of transplantation-associated microangiopathy, sinusoidal obstruction syndrome, or acute graft-versus-host disease. This study proposes EASIX-PRE as a prognostic tool to identify patients undergoing alloHCT at increased risk of severe organ dysfunction and who would therefore require ICU admission. Early identification of patients at high risk of severe events could contribute to personalized intervention design. Additionally, it validates the association between EASIX-PRE and OS and NRM in those undergoing alloHCT.

Abstract: The role of haploidentical hematopoietic cell transplantation (HCT) using posttransplant cyclophosphamide (PTCy) for acute lymphoblastic leukemia (ALL) is being defined. We performed a retrospective, multivariable analysis comparing outcomes of HCT approaches by donor for adults with ALL in remission. The primary objective was to compare overall survival (OS) among haploidentical HCTs using PTCy and HLA-matched sibling donor (MSD), 8/8 HLA-matched unrelated donor (MUD), 7 /8 HLA-MUD, or umbilical cord blood (UCB) HCT. Comparing haploidentical HCT to MSD HCT, we found that OS, leukemia-free survival (LFS), nonrelapse mortality (NRM), relapse, and acute graft-versus-host disease (aGVHD) were not different but chronic GVHD (cGVHD) was higher in MSD HCT. Compared with MUD HCT, OS, LFS, and relapse were not different, but MUD HCT had increased NRM (hazard ratio [HR], 1.42; P = .02), grade 3 to 4 aGVHD (HR, 1.59; P = .005), and cGVHD. Compared with 7/8 UD HCT, LFS and relapse were not different, but 7/8 UD HCT had worse OS (HR, 1.38; P = .01) and increased NRM (HR, 2.13; P ≤ .001), grade 3 to 4 aGVHD (HR, 1.86; P = .003), and cGVHD (HR, 1.72; P ≤ .001). Compared with UCB HCT, late OS, late LFS, relapse, and cGVHD were not different but UCB HCT had worse early OS (≤18 months; HR, 1.93; P & lt; .001), worse early LFS (HR, 1.40; P = .007) and increased incidences of NRM (HR, 2.08; P & lt; .001) and grade 3 to 4 aGVHD (HR, 1.97; P & lt; .001). Haploidentical HCT using PTCy showed no difference in survival but less GVHD compared with traditional MSD and MUD HCT and is the preferred alternative donor HCT option for adults with ALL in complete remission.

Abstract: Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematological malignancy with a poor prognosis and considered incurable with standard conventional chemotherapy. Small observational studies have shown that allogeneic hematopoietic cell transplantation (allo-HCT) offers durable remissions in patients with BPDCN. We conducted an analysis of 164 patients with BPDCN from 78 centers who underwent allo-HCT between 2007-2018 using data reported to the Center for International Blood and Marrow Transplant Research (CIBMTR). Results: Median follow up of survivors was 49 months (range 6-121). 5-year overall survival (OS), disease-free survival (DFS), relapse, and non-relapse (NRM) rates were 51.2% (95% confidence interval [95%CI]: 42.5-59.8%), 44.4% (95%CI: 36.2-52.8%), 32.2% (95%CI: 24.7-40.3%), and 23.3% (95%CI: 16.9-30.4%), respectively. Disease relapse was the most common cause of death. On multivariate analyses, age ≥60 was predictive for inferior OS (hazard ratio [HR] = 2.16, 95% CI 1.35-3.46, p= 0.001), and higher NRM [HR= 2.19, 95% CI 1.13-4.22, p= 0.02]. Remission status at time of allo-HCT (CR2/PIF/Relapse vs CR1) was predictive of inferior OS [HR= 1.87, 95% CI 1.14-3.06, p= 0.01] and DFS [HR= 1.75, 95% CI 1.11-2.76, p= 0.02]. Use of myeloablative conditioning with total body irradiation (TBI) was predictive for improved DFS and reduced risk of relapse. Conclusion: Allo-HCT is effective in providing durable remissions and long-term survival in BPDCN. Younger age and allo-HCT in CR1 predicted for improved survival, while myeloablative conditioning with TBI predicted for less relapse and improved DFS. Novel strategies incorporating allo-HCT are needed to further improve outcomes.

Abstract: Introduction An increased risk of mortality has been documented in transplanted patients affected by Coronavirus Disease 2019 (COVID19) with an estimated mortality rate between 20-40%. Multiple efforts are ongoing to control COVID19 pandemic, and clinical practice is being adapted at the same time as the pandemic progresses around the world. To reduce unnecessary in-person appointments has become crucial to minimize hospital exposition. Digital technologies allow us to perform real-time monitoring of patients' clinical status. A real-time patient monitoring system through the use of a smartphone application and wearable devices was implemented at our Center during the COVID19 pandemic. Methods Since March 2020, a real time patient monitoring system was implemented at our HCT program. All consecutive adults patients transplanted between April 2020 and July 2020 were considered for the study. Vital signs and relevant clinical information were reported during 14 consecutive days after being discharged, through the online platform provided by Trilema Fundation (saludencasa.trilema.org, Fundación Trilema, Valencia, Spain). Vital signs (cardiac frequency, blood pressure, oxygen saturation) were measured with validated oxymeters (Onyx II®, Nonin Inc, Plymouth MN USA) and blood pressure monitors (iHealth Track®, Mountain View, CA USA). Temperature was measured through domiciliary thermometers. Patients were educated to measure their respiratory frequency. A checklist of clinical symptoms was filled daily. An analogue visual scale (0-10) to detect potential cases of anxiety or depressive disorders was reported daily. Scores of & gt;6 were evaluated by a psycho-oncologist through videoconference. All the data were reported to the online platform using a smartphone app compatible with iPhone and Android systems. A direct chat between patients and physician was available through the app. Clinical information was daily supervised by an experienced HCT hematologist. Clinical interventions were arranged if significant clinical abnormalities were documented. A hematologist with experience in HCT patients revised all the patients' data daily. Programmed alarms were set in case of any of the following situations: fever & gt;38 oC; oxygen saturation & lt;92%; tachicardia & gt;125/bpm, hypotension (sytolic & lt;90 mmHg, diastolic & gt; 60 mmHg; altered mental status; persistent emesis or diarrhea). Patient´s satisfaction questionnaires were evaluated individually after finalizing the 14-days clinical monitoring. Results During the study period, 21 adults underwent HCT and 16 were s were eligible to be recruited into the study (80% feasibility) with team effort and without additional costs. Reasons for not being enrolled were: language incompatibility (1 patient), no consent (1 patient), not compatible smartphone (3 patients). Of the 16 enrolled patients, median age was 50 (range 22-70 years), 37% were female and 94% had lymphoid diseases. Thirty-eight percent of HCTs were autologous and 62% allogeneic. Of the 16 enrolled patients, 25% were not able to adequately use the app due to inability in using smartphone applications. Of the remaining 12 patients, adherence in reporting study data (number of days reported of the planned 14 days study period) was as follows (average): temperature 89%, oxygen saturation 90%, respiratory frequency 70%, cardiac frequency 85%, blood pressure 89%, symptoms reporting 65%, emotional distress 71%. Automatic alarms were activated only 3 times: twice for the presence of clinical symptoms and once, for emotional distress. A videoconference with the psycho-oncologist was requested by one patient only. The chat service to communicate with hospital personnel was used in 4 patients. Data collected with the digital system helped the clinician to early recognize arterial hypertension (1 patient) and acute cutaneous GVHD grade 1 (1 patient). Only two patients of the whole cohort were readmitted within 14 days from discharge due to grade 4 odynophagia due to HSV1/2 reactivation. Patients´ experiences with telehealth systems are reported in table 1. Conclusion Telehealth monitoring can potentially improve patient's follow-up in terms of both physical and psychological outcomes. Technological problems still represent a barrier to a wider application of telehealth monitoring systems in the medical setting. Disclosures Mussetti: Novartis, Gilead: Honoraria, Research Funding. Sureda Balari:Incyte: Consultancy; Janssen: Consultancy, Honoraria; Celgene/Bristol-Myers Squibb: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; BMS: Speakers Bureau; Roche: Honoraria; Takeda: Consultancy, Honoraria, Speakers Bureau; Sanofi: Consultancy, Honoraria; Gilead/Kite: Consultancy, Honoraria; Merck Sharpe and Dohme: Consultancy, Honoraria, Speakers Bureau.