ALBERT

Description: Introduction: The role of autologous stem cell transplantation (ASCT) as first line treatment for newly diagnosed patients with myeloma is currently under evaluation given the high response rates to novel induction treatment. The outcomes for patients that do not proceed to ASCT following induction remain unclear and are likely to be determined by genetic risk and response to therapy. In order to evaluate this further, this single arm phase 2 clinical trial conducted at 13 sites in the UK was designed to determine the 2 year progression free survival for patients that achieved ≥ very good partial response (VGPR) following induction therapy without ASCT. Those achieving partial response (PR) were consolidated with ASCT according to routine practice. In this first analysis we report secondary endpoints: disease response and regimen-related toxicity in patients completing induction, including minimal residual disease (MRD) negativity by multiparameter flow cytometry. Methods: Patients with newly diagnosed myeloma eligible for ASCT received PAD (bortezomib 1.3mg/m2 days 1, 4, 8, 11; doxorubicin 9mg/m2 days 1-4 and dexamethasone 40mg days 1-4 (and days 8-11 and 15-18 for the first cycle only)) for up to 6 cycles (minimum of 4). Bortezomib was initially given intravenously (IV), but once approved this was switched to sub-cutaneous (SC). Those failing to achieve PR were offered salvage therapy off protocol. All others had peripheral blood stem cell (PBSC) mobilisation using cyclophosphamide + GCSF, followed by MRD assessment on bone marrow aspirates using multi-parameter flow cytometry. Depending on disease response, patients were then stratified to ASCT (PR) or no further treatment (≥VGPR). Responses were assessed using International uniform response criteria (Durie 2006) by intent-to-treat and toxicity scored according to CTCAE version 4.0. High risk disease was defined by the presence of one or more adverse FISH lesions (t(4;14), t(14;16), t(14;20), del(17p13), +1q21) as described in the MRC Myeloma IX trial. Results: Between March 2011 and January 2014, 153 patients were enrolled (median age of 55, range 28-71 years). 139 (91%) received between 4-6 cycles of PAD. The majority (135, 88%) received SC only bortezomib and 18 (12%) received at least 1 cycle IV. The overall response rate to PAD was 81% with 46% achieving ≥VGPR (sCR: 6 (4%), CR: 13 (8%), VGPR: 51 (33%), PR: 54 (35%)). FISH data was available for 122 patients, 91 (75%) patients were standard risk and 31 (25%) were adverse. Responses were similar irrespective of ISS or genetic risk (standard, ≥VGPR 44%, PR 34%; adverse, ≥VGPR 55%, PR 29%). MRD results are currently available in 70 of the 124 patients achieving PR post PBSC harvest. Of this group 41 achieved ≥VGPR post-harvest (22 MRD+ and 19 MRD-) and hence did not proceed to ASCT, 13 patients achieved CR of which 8 were MRD negative. Toxicity was as expected for PAD and predominantly haematological. Notably the incidence of neuropathy was lower than that previously reported with IV bortezomib. Grade 3-4 events were: neutropenia: 18%; thrombocytopenia 7%. Grade 2-4 peripheral neuropathy was reported in 27% compared to 40% in the HOVON-65/ GMMG-HD4 Trial using IV bortezomib. Grade 1-2 neuropathy was similar for patients who received IV (55.6%) or SC (60%) bortezomib; however only 7% of patients receiving SC bortezomib developed grade 3 neuropathy compared to 28% with the IV route. Conclusions: SC PAD is a highly effective induction regimen for patients with newly diagnosed myeloma achieving a ≥VGPR of 46%. Of the 41 patients achieving ≥VGPR post-harvest with MRD result available, 46% were MRD negative. Response rates were similar across ISS and with adverse FISH. The use of SC bortezomib improved tolerability and substantially reduced neurotoxicity. ISRCTN no: 03381785. Disclosures Popat: Janssen: Honoraria. Cavenagh:Janssen: Honoraria. Schey:Janssen: Consultancy, Honoraria. Cook:Janssen: Consultancy, Honoraria, Research Funding, Speakers Bureau. Cook:Janssen: Honoraria, Research Funding. Yong:Janssen: Honoraria.

Description: Improving outcomes in multiple myeloma will involve not only development of new therapies but also better use of existing treatments. We performed RNA sequencing on samples from newly diagnosed patients enrolled in the phase 2 PADIMAC (Bortezomib, Adriamycin, and Dexamethasone Therapy for Previously Untreated Patients with Multiple Myeloma: Impact of Minimal Residual Disease in Patients with Deferred ASCT) study. Using synthetic annealing and the large margin nearest neighbor algorithm, we developed and trained a 7-gene signature to predict treatment outcome. We tested the signature in independent cohorts treated with bortezomib- and lenalidomide-based therapies. The signature was capable of distinguishing which patients would respond better to which regimen. In the CoMMpass data set, patients who were treated correctly according to the signature had a better progression-free survival (median, 20.1 months vs not reached; hazard ratio [HR], 0.40; confidence interval [CI], 0.23-0.72; P = .0012) and overall survival (median, 30.7 months vs not reached; HR, 0.41; CI, 0.21-0.80; P = .0049) than those who were not. Indeed, the outcome for these correctly treated patients was noninferior to that for those treated with combined bortezomib, lenalidomide, and dexamethasone, arguably the standard of care in the United States but not widely available elsewhere. The small size of the signature will facilitate clinical translation, thus enabling more targeted drug regimens to be delivered in myeloma.

Description: Introduction A standard conditioning regimen for patients undergoing autologous stem cell transplant (ASCT) for relapsed/refractory lymphoma in Europe has consisted of BCNU, etoposide, cytarabine and melphalan (BEAM). BCNU has not been readily available for several years. Thus, in our institution, since August 2008 it has been substituted by oral lomustine (LEAM). There is very limited information on the relative toxicities of the two regimes, and to address this we undertook a retrospective analysis of two comparable groups of transplant patients, to assess the relative toxicity profiles. Methods and Patients Two cohorts of 50 patients undergoing ASCT for relapsed/refractory lymphoma were compared, one conditioned with BEAM (BCNU 300mg/m2, etoposide 1600mg/m2 (in divided doses), cytarabine 800mg/m2 (in divided doses) and melphalan140mg/m2 and the other with LEAM (lomustine 200mg/m2 instead of BCNU). Table 1: Patient Characteristics LEAM BEAM p-value Number of patients 50 50 Time period covered August 2008 – June 2013 Dec 1999 – Sept 2011 Age at Transplant (Median, mean, 95% CI) 52.5; 49.3 (45.9 to 52.6) 51; 48.4 (45.0 to 52.0) 0.73 Male (Number, Proportion) 30 (60%) 24 (48%) 0.32 Diagnosis (n) – DLBCL HL FL 19 15 16 20 16 14 Pre-SCT GFR (ml/min) (Median, mean, 95% CI) 108, 107 (96.6 to 118.2) 87,91.1 (81.4 to 100.8) 0.03 Stem Cell Dose ; CD34x106;kg (Median, mean 95% CI) 2.7, 4.7 (2.76 to 6.6) 2.6, 4 (3.0 to 5.0) 0.7 PET Positive Pre-SCT (Number, Proportion) 14 (38%) 18 (40%) 0.52 Toxicities were assessed for each cohort, using the nursing and medical notes, according to CTCAEv3.0 criteria: nausea, vomiting, stomatitis and diarrhoea, alanine liver transaminase (ALT) for hepatic toxicity and creatinine for renal toxicity. Surrogate markers for mucosal toxicity were also assessed, such as use of anti-diarrhoeals, opiates and syringe-driver anti-emetics. Results The unpaired t-test was used for continuous variables and Fisher's exact test for categorical values. Table 2 LEAM BEAM p-value Length of Admission (Days) (Median; Mean; 95% CI) 23; 26.7 (21.7 to 31.7) 23; 25.4 (23.3 to 27.6) 0.63 ICU Admission (Number, Proportion) 8 (16%) 4 (8%) 0.36 Deaths 2 (4%) 1 (2%) 0.68 Leucocytes 〉1.0 (day) (Median; Mean; 95% CI) 11; 10.6 (10.2 to 10.9) 11; 11.2 (10.6 to 11.9) 0.12 Neutrophils 〉0.5 (day) (Median; Mean; 95% CI) 11; 10.8 (10.4 to 11.2) 11; 11 (10.4 to 11.6) 0.56 Platelets 〉20.0 (day) (Median ;Mean; 95% CI) 12; 12.7 (11.5 to 14.0) 12; 14.1 (12.0 to 16.2) 0.25 TOXICITY Diarrhoea Duration (Days) (Median; Mean; 95% CI) 12; 14 (10.9 - 17.11) 10.5; 11.5 (9.6 - 13.4) 0.17 Anti-Diarrhoeal Use (n, proportion) 35 (75%) 38 (76%) 0.66 Opiate Use (n, proportion) 35 (70%) 30(60%) 0.4 Syringe Driver Antiemetic Use (n, proportion) 19 (38%) 21 (42%) 0.84 GI symptoms at 2 Weeks - (n, proportion) 28 (67%) 23 (52%) 0.060 GI Symptoms at 3 Months (n, proportion) à 17(41%) 7 (14%) 0.001 Alive in CR at 3 Months – (n, proportion) º 45 (96%) 45 (98%) 0.68 8 LEAM + 5 BEAM patients were not evaluable 2 weeks post discharge. à9 LEAM + 8 BEAM patients were not evaluable at 3 months. º47 LEAM and 46 BEAM patients assessable at 3 months. There was minimal non-relapse mortality in both cohorts, with 2 early deaths with LEAM (at D+6 and D+8 respectively) and 1 early death with BEAM (day +7) all secondary to neutropenic sepsis. As expected, significant mucosal toxicity was seen with both regimens, with 51% of patients having at least grade 3 diarrhoea, and approximately 30% having grade 3 stomatitis. There was no statistically significant difference in any of the toxicity parameters measured between the 2 regimens during the inpatient admission. The finding of a statistically significant excess of GI toxicity with LEAM at 3 months (mainly residual abdominal pain and diarrhoea) was not expected, and was not seen when assessed at an earlier time point (2 weeks post discharge). Both regimens were associated with minimal hepatic and renal toxicity. Conclusions There appears to be an excess of late gastrointestinal toxicity associated with the LEAM regimen. However, this toxicity was not associated with a difference in time to engraftment and there was no detectable difference in non-relapse mortality. The cause of this GI toxicity signal is unclear, and requires confirmation and further investigation. There also appears to be no difference in clinical outcomes, however longer follow-up of patients conditioned with LEAM is required to confirm this finding in a more robust manner. Disclosures No relevant conflicts of interest to declare.

Description: Background:Patients with acute myeloid leukemia (AML), myelodysplasia (MDS) or tyrosine kinase inhibitor resistant chronic myeloid leukemia (CML) who are unsuitable for consolidative allogeneic stem cell transplantation (alloSCT) have high relapse rates following chemotherapy. Wilms' tumor 1 (WT1) is highly expressed in the majority of acute myeloid leukemias (AML) and in many subtypes of myelodysplasia (MDS) as well as other hematological and solid tumors. WT1 is an intracellular antigen, which makes it difficult to target using current Chimeric Antigen Receptor (CAR)-T cell technologies. The use of genetically modified T cells expressing WT1-specific α/β T cell receptors can re-direct T cell specificity via the recognition of intracellular peptides presented by MHC molecules on the malignant cell surface. Phase I clinical trials of WT1-TCR gene-modified T cells have been conducted in the settings of relapsed disease and post-alloSCT and preliminary data suggests this treatment approach is safe and potentially clinically effective in these cohorts (Tawara et al. Blood. 2017;130(18):1985-94; Chapuis et al, Nat Med. 2019;25(7):1064-72). Methods:We report a phase I/II safety and dose escalation study evaluating WT1-TCR gene-modified autologous T cells in HLA-A*0201 positive patients with AML, MDS and CML, unsuitable for alloSCT (NCT02550535) (Fig 1A). Patient T cells were harvested by leucapheresis and transduced with a retroviral vector construct encoding the codon optimised variable and constant a and bchains of the human pWT126-specific TCR separated by a self-cleaving 2A sequence (Fig 1B). Bulk transduced T cells were analysed by flow cytometry (CD3, CD8 and Vb2.1) prior to infusion and at regular intervals post-infusion. A quantitative PCR assay was developed to identify WT1-TCR expressing T cells in the peripheral blood post infusion. Patients received minimal conditioning with fludarabine and methylprednisolone prior to transfer of transduced T cells. All subjects were followed for a minimum of 12 months or until death. Results:A total of 10 patients (6 AML, 3 MDS and 1 TKI- resistant CML) were recruited. The mean age was 71.3 years (range 64-75) and all had high risk disease (by cytogenetic or clinical criteria). All AML patients were in complete morphological remission at the time of trial entry, whilst MDS patients had ≤ 15% blasts on bone marrow examination. All 10 patients received the gene-modified T cells in dose escalation cohorts (seven patients received £2x107/kg and three patients received £1x108/kg bulk WT1 TCR transduced cells). No adverse events directly attributable to the investigational product were recorded apart from one possible cytokine release syndrome, which was managed without tociluzimab. Transferred T cells demonstrated in vivoproliferation commensurate with maintenance of functional capacity despite ex vivo manipulation (Fig 1C and 1D). The TCR-transduced T cells were detectable in all patients at 28 days and in 7 patients persisted throughout the study period (Fig 1E). All 6 AML patients were alive at last follow up (median 12 months; range 7-12.8 months). The 3 patients with MDS had a median survival of 3 months (range 2.1-3.96 months) post T cell infusion. 2 died from progressive disease and one from other causes. 2 patients discontinued the study early due to disease progression. Conclusions: This is the second reported phase I/II clinical trial of autologous WT1-TCR gene-modified T cells for treatment of AML and MDS in a high-risk cohort of patients not suitable for alloSCT. We have shown that the WT1-TCR T cells demonstrated a strong safety profile without detectable on-target, off-tumour toxicity and no severe adverse events in the ten patients treated. An important cause of treatment failure for adoptive cellular therapies is the lack of persistence of transferred T cells leading to loss of disease specific effects. We demonstrated that autologous WT1-TCR T cells proliferated in vivoand persisted for many months. Recent work within our group (in press) has shown that TCRs modified to include key framework residues, show increased TCR expression and functional improvement. These modifications could be incorporated into future studies to improve efficacy. This data supports the rationale for a larger, phase II trial of WT1-TCR T cells in myeloid malignancies in patients for whom alloSCT is not appropriate, in order to assess clinical efficacy. Figure 1 Disclosures Morris: Quell Therapeutics: Consultancy, Other: Scientific Founder,stock; Orchard Therapeutics: Consultancy. Qasim:CellMedica: Research Funding; Bellicum: Research Funding; UCLB: Other: revenue share eligibility; Autolus: Equity Ownership; Orchard Therapeutics: Equity Ownership; Servier: Research Funding. Mount:Gamma Delta Therapeutics: Employment. Inman:Cellmedica: Employment. Gunter:Cellmedica: Employment. Stauss:Cell Medica: Other: I have stock; Quell Therapeutics: Consultancy, Other: I have stock.

Description: A major challenge in modern myeloma management is the selection of the best initial treatment from a plethora of available therapies. PAD (bortezomib, doxorubicin, and dexamethasone) is a highly effective regimen which may obviate the need for an upfront high-dose melphalan stem cell transplant (HDSCT). However, it is not clear a priori which patients will benefit from this treatment. In the phase 2 PADIMAC trial, patients with newly diagnosed myeloma were treated with six cycles of PAD and stratified to receive HDSCT in partial remission (PR) or watch and wait in very good partial remission (VGPR) or better. To identify predictive biomarkers, we extracted somatic RNA prior to treatment and performed massively parallel RNA sequencing (RNAseq). Basic quality control metrics suggested a high-quality RNAseq dataset. Furthermore, spiked expression of IgH fusion partners was consistent with fluorescent in situ hybridization (FISH) data for each sample. All t(4;14) and t(4;16) cases were correctly identified by RNAseq on the basis of the relevant fusion transcript. As a final quality control measure, recurrent variants (e.g. NRAS, KRAS, TP53, FAM46C, DIS3) were identified in the expected proportions. We performed a pre-planned analysis of differential gene expression between those patients achieving a VGPR or better, sustained for at least 12 months without HDSCT (excellent responders), and those patients who achieved less than a PR (poor responders). 85 genes were upregulated in poor responders and 225 in excellent responders. Interestingly, there was no significant overlap between our PAD-predictive signature and the Arkansas 70 gene poor prognosis signature, the Arkansas 17 gene poor prognosis signature, or the EMC92 prognostic signature. This is likely to reflect in part, the greater sensitivity of RNAseq for gene expression compared to microarrays. However, it also implies that there is a selective signature for PAD responsiveness. We employed the Gage and Pathview packages to identify non-redundant pathways associated with PAD responsiveness. Significantly upregulated genes in poor responders were those involved in: DNA replication, base excision repair, and the Fanconi anaemia pathway. Genes upregulated in excellent responders included those involved in: several signalling pathways (including RAS, NF-Kappa B, FOXO and JAK-STAT pathways); chemokine and cell adhesion; protein processing in the endoplasmic reticulum; and immune activation pathways such as T-cell receptor signalling and natural killer cell-mediated cytotoxicity. Finally, we investigated the ability of expression signatures to stratify patients on the basis of PAD responsiveness. Our analysis suggests that RNASeq-defined transcriptional profiles could aid in the selection of patients for PAD therapy (leading to an increase in overall response rate from 70% to 86%), as well as the stratification of patients in CR to a non-HDSCT protocol. We anticipate that our current analysis could easily incorporate specific response signatures for other regimens and could make personalized therapy for myeloma a reality in the foreseeable future. Disclosures Yong: Autolus Ltd: Equity Ownership, Patents & Royalties: APRIL based chimeric antigen receptor; Janssen: Research Funding. Streetly:Guys and St. Thomas' NHS Trust: Honoraria. Schey:Celgene, Takeda: Honoraria; Celgene: Consultancy; Celgene, Johnson & Johnson: Speakers Bureau. Cook:Amgen: Consultancy, Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Research Funding, Speakers Bureau; Glycomimetics: Consultancy, Honoraria; Takeda: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Sanofi: Consultancy, Honoraria, Speakers Bureau; Bristol-Myers Squibb: Consultancy, Honoraria. Cook:Takeda: Honoraria; Amgen: Honoraria; Celgene: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Myeloma UK: Membership on an entity's Board of Directors or advisory committees.

Description: The ETV6-ABL1 fusion gene, as consequence of a t(9;12)(q34;p13), is a rare but recurrent genetic aberration found in chronic or blast phase of eosinophilia-associated myeloproliferative neoplasms (MPN-eo) and de novo acute B-cell lymphoblastic leukemias (B-ALL) or lymphoblastic T-cell lymphomas (T-LBL). Here, we sought to evaluate a) relevant clinical characteristics, b) treatment options and c) survival in 7 ETV6-ABL1 positive patients (male, n=4; median age 46 years; range 20-61). Cytogenetic analyses revealed a conventional reciprocal translocation t(9;12)(q34;p13) in 3 cases, an ins(12;9)(p13;q34q22) and a normal karyotype in one patient each, and a complex karyotype in 2 patients. In all cases, ETV6-ABL1 was confirmed by FISH analysis and/or RT-PCR. Histopathological diagnoses of the hypercellular bone marrow (BM) included atypical chronic myeloid leukemia (n=3), MPN-eo (n=3, concomitant T-LBL in one patient) or chronic myelomonocytic leukemia (n=1). In peripheral blood, all patients presented with left shifted leukocytosis (median 84 x 109/l, range 21-143) and significant (〉1.5 x 109/l) eosinophilia (median 6.1 x 109/l, range 2.0-7.1) but without increased blast cells. Splenomegaly was present in 60% of patients. After a median of 3 months (range 0-6) from diagnosis, all patients were treated with a TKI (imatinib, n=5; dasatinib, n=1; nilotinib, n=1) at standard doses. On dasatinib (#2) or nilotinib (#3), 2 patients achieved a complete hematologic remission (CHR) within 3 months and complete cytogenetic remission (CCR) after 5 months (#3) or complete molecular remission (CMR) after 18 months (#2), respectively (Figure). On imatinib (n=5), 2 of 5 patients (#4 and #5) achieved a CHR within 3 months with loss of CHR after 9 (#4) and 5 months (#5), respectively. Patient #4 developed a myeloid sarcoma. After local radiation, he received an allogeneic stem cell transplant (SCT) but died 8 months later due to GvHD while in CMR. Patient #5 switched to nilotinib and achieved a CCR and CMR after 3 and 10 months, respectively. Patient #1 has not achieved a significant response after 4 months on imatinib. Patient #6 showed progressive disease within 2 months on imatinib, but achieved a rapid CHR and durable CCR and CMR on dasatinib after 13 and 14 months, respectively. Patient #7 presented with a classical myeloid/lymphoid (T-LBL) neoplasm with eosinophilia (MLN-eo) according to the WHO classification. On imatinib, a regression of lymphadenopathy, but persistence of leukocytosis and eosinophilia was observed. With increasing leukocytosis and reappearance of lymphadenopathy, the patient was switched to dasatinib (9 months), followed by nilotinib (2 months). The responses were only partial and transient and the patient died 23 months after diagnosis with myeloid blast phase (secondary acute myeloid leukemia). Overall, after a median treatment time of 22 months (range, 3-58), 4 patients are in CCR (n=1, patient #3) or CMR (n=3; patients #2, #5, #6) while on a second generation TKI and two patients (#4, #7) have died. On imatinib, none of 5 patients achieved a CCR or CMR. We conclude that a) cytogenetic analysis is an important tool for the identification of potential TK fusion genes such as ETV6-ABL1, b) ETV6-ABL1 is a candidate for incorporation into the WHO-defined subcategory ´MLN-eo´, c) patients with MPN-eo can achieve durable CHR, CCR or CMR on TKI with second generation TKI being more effective than imatinib d) close monitoring by cytogenetics, FISH and RT-PCR is recommended for early identification of inadequate response or resistance. Figure (A) responses and (B) overall survival in 7 patients with ETV6-ABL1 positive MPN-eo treated with various tyrosine kinase inhibitors.Abbreviation, CHR:complete hematologic response; CCR: complete cytogenetic response; CMR: complete molecular response; CP: chronic phase; BP: blast phase; allo SCT: allogeneic stem cell transplantation. Figure. (A) responses and (B) overall survival in 7 patients with ETV6-ABL1 positive MPN-eo treated with various tyrosine kinase inhibitors.Abbreviation, CHR:complete hematologic response; CCR: complete cytogenetic response; CMR: complete molecular response; CP: chronic phase; BP: blast phase; allo SCT: allogeneic stem cell transplantation. Disclosures Somervaille: Novartis: Consultancy, Honoraria; Imago Biosciences: Consultancy. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

Description: Abstract 2025 The benefit of high dose therapy and autologous stem cell transplant (HDT-SCT) using cyclophosphamide/total body irradiation conditioning in patients with relapsed follicular lymphoma (FL) has been demonstrated in the pre-rituximab era (European CUP trial. Schouten JCO 2003 21 3198). The long term outcome following HDT-SCT using BEAM (carmustine 300mg/m2 on d-6, cytarabine 200mg/m2 bd iv on days −5 to −2, etopside 200mg/m2 on days −5 to −2 and melphalan 140mg/m2 on d-1 with stem cell return the next day) conditioning is less well documented. It also remains unknown whether BEAM SCT is of similar efficacy in patients who have previously received rituximab compared with those who were rituximab naïve prior to SCT. In addition the optimal timing for HDT-SCT remains contentious. In order to try and resolve some of these uncertainties we undertook a retrospective analysis of all patients who have undergone BEAM SCT for FL in our institution. Eighty patients (53 male, 27 female) with FL underwent BEAM SCT between 1988 and 2009; all but 2 of these patients received their transplant after 1994. The median time from diagnosis to HDT was 2.8 years (range 0.5– 32.8). The median age at transplant was 52 (range 34–67). The median number of lines of therapy prior to SCT was 3 (range 1–5). The majority were transplanted in either their 2nd (n=41) or 3rd (n=20) response, with 13 in their 1st, and 6 in their 4th or subsequent response. Eight of the 13 transplanted in 1st response had received 2 or more lines of therapy prior to HDT-SCT. Forty-six patients (63%) received rituximab (either as a monotherapy or in combination with chemotherapy) as a treatment line before SCT. The median follow up is 6.8 years (range 0.1–19.2). The 7yr overall survival (OS) and progression free survival (PFS) of the whole group as measured from the date of the transplant were 75.6% and 59.5% respectively. The median OS has not yet been reached (NYR) whilst the median PFS is 12.5yrs. Excluding patients transplanted in 1st remission, the 7yr OS, PFS, median OS and median PFS were 74.6%, 58.0%, NYR and 9.4yrs respectively. There were highly significant differences in survival outcomes for patients transplanted in 2nd versus 3rd response: 7yr OS was 83.5% vs 61.1% (p=0.0201) and 7yr PFS was 67.0% vs 42.1% (p=0.0125) respectively (Fig1a). To date there have been no overt relapses after 6yrs in patients transplanted in 2nd response, with the caveat that patients have not been subjected to regular follow up imaging if they have no clinical symptoms or signs of relapse. When patients who had received rituximab prior to HDT-SCT were compared to those who had not there were no significant differences: 7yr OS 81.4% vs 67.6% (p=0.152) and 7yr PFS 68.0% vs 46.8% (p=0.221) (Fig1b). When analysis was restricted only to patients transplanted in 2nd response, once again no significant differences were found according to prior rituximab exposure: 7yr OS 87.1% vs 76.2% (p=0.297) and 7yr PFS 72.2% vs 53.8% (p=0.125). Conclusions: HDT-SCT using BEAM conditioning appears to be highly efficacious with long PFS and OS times. In our series, patients transplanted in 2nd response fare significantly better than those transplanted in 3rd response though further follow up is needed to clearly establish whether a plateau has been reached in the former group. Finally we have shown that treatment with a rituximab-containing regimen prior to BEAM-SCT does not lessen the benefit of BEAM-SCT when compared with patients who had not received rituximab prior to BEAM-SCT. BEAM-SCT therefore remains a valid treatment option for patients with FL in the rituximab era. Disclosures: Ljubic: Roche: Salary funded by a grant.

Description: Ligation of the cell-surface Fas molecule by its ligand (Fas-L) or agonistic anti-Fas monoclonal antibodies results in the cleavage and activation of the cysteine protease procaspase 8 followed by the activation of procaspase 3 and by apoptosis. In some leukemia cell lines, cytotoxic drugs induce expression of Fas-L, which may contribute to cell killing through the ligation of Fas. The involvement of Fas, Fas-L, and caspase 8 was studied in the killing of B-cell chronic lymphocytic leukemia (B-CLL) cells by chlorambucil, fludarabine, or γ radiation. Spontaneous apoptosis was observed at 24-hour incubation, with additional apoptosis induced by each of the cytotoxic treatments. Although Fas mRNA expression was elevated after exposure to chlorambucil, fludarabine, or γ radiation, Fas protein levels only increased after irradiation. Therefore, Fas expression may be regulated by multiple mechanisms that allow the translation of Fas mRNA only in response to restricted cytotoxic stimuli. None of the cytotoxic stimuli studied here induced Fas-L expression. An agonistic anti-Fas monoclonal antibody (CH-11) did not significantly augment apoptosis induction by any of the death stimuli. A Fas-blocking antibody (ZB4) did not inhibit spontaneous, chlorambucil-, fludarabine-, or radiation-induced apoptosis. However, procaspase 8 processing was induced by all cytotoxic stimuli. These data suggest that the Fas/Fas-L signaling system does not play a major role in the induction of apoptosis in B-CLL cells treated with cytotoxic drugs or radiation. However, Fas-independent activation of caspase 8 may play a crucial role in the regulation of apoptosis in these cells.

Description: Introduction: Carfilzomib (20/36mg/m2) triplets with Lenalidomide-Dexamethasone (KRd), or Cyclophosphamide-Dexamethasone (KCd) are safe and effective in patients with newly diagnosed multiple myeloma(NDMM). The higher dose of 56mg/m2 is effective as a doublet with Dexamethasone in the relapsed setting, but there is limited data on this dose in triplet combinations in the frontline setting. Aim: The CARDAMON study evaluated KCd with bi-weekly carfilzomib (56mg/m2) as induction in NDMM patients, and the benefit of ASCT versus K56Cd consolidation followed by carfilzomib maintenance. Co-primary endpoints were major response (≥VGPR rate) to 4 induction cycles of K56Cd, and 2-year PFS for ASCT versus K56Cd consolidation. Here we report interim analysis of the first primary endpoint of ≥VGPR rate to K56Cd induction. Methods: Transplant eligible ND patients received 4 x 28d cycles of K56Cd (carfilzomib:20/56mg/m2, IV d1, 2, 8, 9, 15, 16, cyclophosphamide 500mg orally d1, 8, 15 and dexamethasone 20mg d1, 2, 8, 9, 15, 16). Responding patients with a successful stem cell harvest (PBSCH) were randomised to autologous stem cell transplant (ASCT) or 4 more cycles of K56Cd as consolidation, followed by 18 months carfilzomib maintenance (K56 days 1, 8, 15) for both arms. Trial recruitment completed in July 2019. Response was assessed by IMWG criteria; all patients had MRD testing by multi-parameter flow cytometry (10-5) after PBSCH. Adverse risk genetics was any one of t(4;14), t(14;16), t(14,20) or del(17p). Results: 281 pts were registered between 06/2015 and 07/2019; we report outcomes for 252 patients who either completed induction or came off study before end of induction. Median age was 58yrs(33-74), 91% ECOG 0-1, 45.2% ISS I, 24.7% adverse risk (48.5% when including 1p/1q+). Best response at end of induction or after PBSCH (n=250) was: ≥VGPR 59.2%, ORR 87.6%. ≥VGPR rate in adverse risk patients was 53.4% vs 61.9% in standard risk(SR), (p=0.25), ORR was similar: adverse risk, 87.9% vs standard risk, 88.1%. Post-PBSCH, 24.1% of patients were MRD-negative (patients who were withdrawn due to insufficient induction response or toxicity and those with an inconclusive result were grouped with the MRD-positive). Of 19 patients in sCR/CR, 9 were MRD-negative(47.4%) while 40/110 (36.4%) of VGPR patients were MRD-negative. MRD-negative rates in adverse and standard risk patients were 22.8% and 24.7% respectively. 10 patients progressed during or at end of induction, and 12 were withdrawn for toxicity. There were 4 deaths during induction, one from myocardial infarction, the other 3 from cardiac arrest, associated with bronchopneumonia and sepsis. During induction, 114 serious adverse events (SAEs) were reported in 72/252 patients, notable ones were thrombotic microangiopathy (2), grade 3 cardiac ischaemia (4), infection (16.3%, mainly lung), renal impairment (6), G3 hypertension (3), thromboembolism(2). Specific guidance for hypertension management was incorporated. 25% of patients are currently reported to have received a dose modification during induction. Full details of adverse events and dose intensity will be presented at the meeting. Conclusion: K56Cd is an effective induction regimen in NDMM patients, and has equivalent MRD negative rates in adverse and standard risk disease. The SAE profile is in keeping with published safety data with carfilzomib. Disclosures Yong: Sanofi: Speakers Bureau; Amgen: Research Funding, Speakers Bureau; Autolus: Consultancy; Janssen: Speakers Bureau; Takeda: Research Funding, Speakers Bureau. Popat:Celgene Corporation: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: travel, accommodations, expenses; Janssen: Honoraria, Other: travel support to meetings; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees; GSK: Consultancy, Honoraria; Takeda: Honoraria, Other: travel, accommodations, expenses. Ramasamy:Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; NAPP Pharmaceuticals Ltd.: Research Funding; Janssen-Cilag Ltd.: Research Funding; Oncopeptides and Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Membership on an entity's Board of Directors or advisory committees. Chapman:Takeda: Honoraria. Benjamin:Allogene: Research Funding; Gilead: Honoraria; Novartis: Honoraria; Pfizer: Research Funding; Amgen: Honoraria; Takeda: Honoraria; Servier: Research Funding; Eusapharm: Consultancy. Owen:Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Other: Travel/ meeting support. OffLabel Disclosure: Carfilzomib is used with cyclophosphamide as 1st line treatment for myeloma