Phase I study of zoledronic acid combined with escalated doses of interleukine-2 for early in vivo generation of Vγ9Vδ2 T-cells after haploidentical stem cell transplant with posttransplant cyclophosphamide.

The presence of donor Vγ9Vδ2 T-cells after haploidentical hematopoietic stem cell transplant (h-HSCT) has been associated with improved disease-free survival. These cells kill tumor cells in a non-MHC restricted manner, do not induce graft-versus-host disease (GVHD), and can be generated by stimulation with zoledronic acid (ZA) in combination with interleukin-2 (IL-2). This monocentric phase I, open-label, dose-escalating study (ClinicalTrials.gov: NCT03862833) aimed at evaluating the safety and possibility to generate Vγ9Vδ2 T-cells early after h-HSCT. It applied a standard 3 + 3 protocol to determine the maximum tolerated dose (MTD) of increasing low-doses of IL-2 (5 days [d] per week, 4 weeks) in combination with a single dose of ZA, starting both the first Monday after d + 15 posttransplant. Vγ9Vδ2 T-cell monitoring was performed by multiparameter flow cytometry on blood samples and compared with a control cohort of h-HSCT recipients. Twenty-six patients were included between April 2019 and September 2022, 16 of whom being ultimately treated and seven being controls who received h-HSCT only. At the three dose levels tested, 1, 0, and 1 dose-limiting toxicities were observed. MTD was not reached. A significantly higher number of Vγ9Vδ2 T-cells was observed during IL-2 treatment compared with controls. In conclusion, early in vivo generation of Vγ9Vδ2 T-cells is feasible after h-HSCT by using a combination of ZA and repeated IL-2 infusions. This study paves the way to a future phase 2 study, with the hope to document lesser posttransplant relapse with this particular adaptive immunotherapy.

B Cell Aplasia Is the Most Powerful Predictive Marker for Poor Humoral Response after BNT162b2 mRNA SARS-CoV-2 Vaccination in Recipients of Allogeneic Hematopoietic Stem Cell Transplantation.

Little is known about the immune response to SARS-CoV-2 vaccination in recipients of allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, several studies have reported that adequate protection could be provided to this population. The purpose of this study was to evaluate which factors can predict the efficacy of SARS-CoV-2 vaccination in these specifically immunosuppressed patients. Specific anti-Spike (S) antibody responses were assessed in a cohort of 117 allo-HSCT recipients after 2 injections of BNT162b2 mRNA SARS-CoV-2 vaccine (V1 and V2). Factors considered liable to influence the antibody response and analyzed in this series were the interval between allo-HSCT and V1, donor source, recipient and donor age, current immunosuppressive/chemotherapy (I/C) treatment, and levels of CD4+and CD8+ T cells, B cells, and natural killer cells at the time of V1. Overall, the S-antibody response rate, evaluated at a median of 35 days after V2, was 82.9% for the entire cohort, with 71 patients (61%) reaching the highest titer. In univariate analysis, a lower pre-V1 median total lymphocyte count, lower CD4+ T cell and B cell counts, ongoing I/C treatment, and a haploidentical donor were characteristic of nonhumoral responders. However, multiparameter analysis showed that B cell aplasia was the sole factor predicting the absence of a specific immune response (odds ratio, 0.01; 95% confidence interval, 0.00 to 0.10; P < 10-3). Indeed, the rate of humoral response was 9.1% in patients with B cell aplasia versus 95.9% in patients with a B cell count >0 (P < 10-9). These results advocate for the administration of anti-SARS-CoV-2 vaccination in allo-HSCT recipients as early as peripheral B cell levels can be detected, and also suggest the need for close monitoring of B-cell reconstitution after Allo-HSCT.

Safety and immunogenicity of a first dose of SARS-CoV-2 mRNA vaccine in allogeneic hematopoietic stem-cells recipients.

This was a monocentric prospective study testing the efficacy and safety of a first injection of BNT162b2 (Pfizer-BioNTech) in 112 Allo-HSCT patients. Antibody response to SARS-CoV-2 spike protein receptor-binding domain was tested at the time of the second injection (Roche Elecsys). The study also included a non-randomized control arm of 26 healthy controls. This study shows that a first dose of SARS-CoV-2 messenger RNA vaccine is safe and provides a 55% rate of seroconversion in allotransplanted patients compared to 100% for the controls (p < 0.001). Factors influencing the absence of response in patients were recent transplantation (<2 years), lymphopenia (<1 × 109/L) and immunosuppressive treatment or chemotherapy at the time of vaccination.

A new cytokine-based dynamic stratification during induction is highly predictive of survivals in acute myeloid leukemia.

The aim of this study was to assess the potential impact of the kinetics of serum levels of seven cytokines during induction in acute myeloid leukemia (AML) patients. Indeed, the role of cytokines, in the pathophysiology and response to therapy of AML patients, remains under investigation. Here, we report on the impact of peripheral levels of two cytokines, the Fms-like tyrosine kinase 3 ligand (FL) and interleukin-6 (IL-6), evaluated during first-line intensive induction. A new risk stratification can be proposed, which supersedes the ELN 2017 classification to predict survivals in AML patients by examining the kinetic profile of these cytokines during the induction phase. It segregates three groups of, respectively, high-risk, characterized by a stagnation of low FL levels, intermediate risk, with dynamic increasing FL levels and high IL-6 at day 22, and favorable risk with increasing FL levels but low IL-6 at day 22.

Grade 2 acute GVHD is a factor of good prognosis in patients receiving peripheral blood stem cells haplo-transplant with post-transplant cyclophosphamide.

BACKGROUND: The impact of acute graft versus host disease (GVHD) on survivals for patients receiving a haploidentical allogeneic stem-cell transplant (Allo-SCT) with peripheral blood stem-cells (PBSC) complemented by post-transplant cyclophosphamide (PTCY) is ill-known. MATERIAL AND METHODS: This retrospective study included 131 patients who received a PBSC haplograft in order to precise the impact of acute GVHD on outcomes. There were 78 males and 53 females and the median age for the whole cohort was 59 years (range: 20-71). Thirty-five patients were allografted for a lymphoid disease and 96 for a myeloid malignancy, including 67 patients with acute myeloid leukemia (AML). RESULTS: The cumulative incidence (CI) of day 100 grade 2-4 and 3-4 acute GVHD was 43.4 + 4.6% and 16.7 + 3.4%, respectively. The 2-year CI of moderate/severe chronic GVHD was 10.1 + 2.8%. The only factor affecting the occurrence of GVHD was GVHD prophylaxis. Indeed, CI of day 100 grade 2-4 (but not grade 3-4) acute GVHD was significantly reduced when adding anti-thymoglobulin (ATG) to PTCY. However, in multivariate analysis, grade 2 acute GVHD was significantly associated with better disease-free (HR: 0.36; 95%CI: 0.19-0.69, p = .002) and overall (HR: 0.35; 95%CI: 0.1-0.70, p = .003) survivals. The same results were observed when considering only AML patients. CONCLUSION: Acute grade 2 GVHD is a factor of good prognosis after PBSC haplotransplant with PTCY. Further and larger studies are needed to clarify the complex question of GVHD prophylaxis in the setting of haplo-transplant, especially that of combining ATG and PTCY.

Autologous stem-cell collection following VTD or VRD induction therapy in multiple myeloma: a single-center experience.

Triplet-drug regimen bortezomib-thalidomide-dexamethasone (VTD) and bortezomib-lenalidomide-dexamethasone (VRD) are considered as standard of care induction prior autologous stem-cell transplantation (ASCT) in myeloma. In addition to improve response rate, induction therapy should preserve an adequate stem-cell collection. In the present retrospective study, we analyzed stem-cell collection in 325 newly diagnosed myeloma patients who received either VTD or VRD induction before ASCT. Stem-cell mobilization consisted of intravenous cyclophosphamide plus G-CSF. Plerixafor was administered preemptively to rescue mobilization. In comparison with VTD, VRD induction was associated with a more frequent use of plerixafor (19.3% versus 5.4%, p = 0.004) and with an increased number of apheresis to reach adequate collection (>2 apheresis required in 42.3% versus 30.2%, p = 0.05). Moreover, more patients experienced collection failure in the VRD group (6% versus 1.8%, p = 0.004). The median number of CD34-positive cells (×106/kg) was lower in the VRD group: 8.5 versus 9.3 (p = 0.05) in the VTD group. The vast majority of patients underwent ASCT (93% versus 98%, in VRD and VTD group, respectively). These data highlight the need of optimal stem-cell collection strategy, especially in the context of tandem transplantation and incorporation of anti-CD38 monoclonal antibody into induction.

Progression of disease within 2 years (POD24) is a clinically relevant endpoint to identify high-risk follicular lymphoma patients in real life.

Follicular lymphoma (FL) is an indolent non-Hodgkin's lymphoma with heterogeneous outcomes. Progression or relapse of FL within 2 years (so-called POD24) after diagnosis is associated with a poor outcome for patients treated with R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, prednisone) in clinical trials. POD24 needs further validation before it can be used as a relevant endpoint to assess treatment efficacy. In the present retrospective monocentric study, we investigated the predictive value of POD24 in a cohort of grade 1, 2, or 3a FL patients treated in our institution (Nantes Medical University, France) and registered in our local database. We investigated the nature of treatment lines, patients' outcomes, and the prognostic value of POD24. Between 2007 and 2016, 317 patients were included. After first-line therapy, 60 patients relapsed within 2 years (POD24-pos cohort), and 254 patients did not relapse within 2 years (PO24-neg cohort). Thirty-three patients died, and 34 patients had an aggressive transformation. The median follow-up is 59.9 months (1.6-395.5). The median PFS is 59.9 months. Overall survival (OS) at 1 year, 3 years, and 5 years is 98.4% [97.0-99.8], 95.1% [92.6-97.6], and 92.5% [89.3-95.9], respectively. The 5-year OS was statistically lower for POD24-pos patients (82% [71.9-93.5]) than for POD24-neg patients (93.3% [88.98-97.8]) (p = 10-5). In multivariate analyses, transformation was predictive of OS, and PS (≥ 1) was predictive of POD24. POD24 is predictive of a worse OS and may be recommended as a relevant endpoint in clinical trials and in real life in particular for patients with advanced disease.

Absence of influence of peripheral blood CD34+ and CD3+ graft cell counts on outcomes after reduced-intensity conditioning transplantation using post-transplant cyclophosphamide.

The influence of peripheral blood stem cell (PBSC) graft cell contents after transplant with post-transplant cyclophosphamide (PTCY) remains unclear. Here, we retrospectively report on a cohort of 77 adults who received a Baltimore-based reduced-intensity conditioning regimen either with fludarabine (n = 40) or clofarabine (n = 37) and PTCY. With a median follow-up of 29.2 months, [2-]year overall (OS), disease-free (DFS), and GVHD/relapse-free survival (GRFS) rates were 62.8%, 51%, and 36.7%, respectively. The incidence of grades [2-]4 acute GVHD was significantly higher in patients transplanted with a haplodonor (n = 56), at 57.1% vs 19% (p = 0.006). PBSC graft cell contents (CD45+, CD34+, and CD3+ cells) had no impact on any outcome. Considering immune reconstitution until 1 year, only monocytes were above the normal range (as early as day + 30) during the first year post-transplant. In multivariate analysis, an older donor (> 45 years) and a high/very high disease risk index were independently associated with lower OS. A higher monocyte count (> median) at day + 90 was also associated with better OS, DFS, and GRFS. Donor/recipient CMV status matching was independently associated with GRFS. In conclusion, our data support the fact that there is no need to manipulate the graft before infusion in the particular context of PBSC/PTCY Baltimore-based allotransplant.

The MYRACLE protocol study: a multicentric observational prospective cohort study of patients with multiple myeloma.

BACKGROUND: Despite recent advances in the treatment of multiple myeloma, the disease constantly relapses and is still considered as incurable. The current knowledge about the biological mechanisms underlying resistance to the different class of drugs in multiple myeloma remains poor. The primary objective of the MYRACLE (Myeloma Resistance And Clonal Evolution) cohort, a multicenter prospective cohort of patients with multiple myeloma, is to address this limitation. We here describe the study background, design and methods used for this cohort. METHODS/DESIGN: All patients (> 18 year old) diagnosed with de novo or relapsed multiple myeloma and treated in two hematology department from west of France are included in the MYRACLE cohort. Patients provide a signed informed to be included in the study. All subjects are followed until refusal to participate in the study or death. The MYRACLE cohort prospectively collects data on socio-economic status, medical status, imaging, prognosis factors, MM therapies and associated events (resistance, safety issues). Patients also complete standardized quality of life questionnaires. In addition, bone marrow samples will be collected at time of diagnosis and relapses to perform biomarkers analysis and functional assays exploring mechanisms underlying drug resistance. DISCUSSION: The "real-life" MYRACLE cohort offers the opportunity to prospectively collect epidemiological, medical, QoL and biological data from MM patients during the course of the disease (at time of diagnosis and subsequent relapses). At mid-tem, this integrative cohort will be unique at producing a large variety of data that can be used to conceive the most effective personalized therapy for MM patients. Additionally, the MYRACLE cohort will allow integrating the medical care of MM patients in a health and pharmacoeconomic perspective.

Influence of Donor Type (Sibling versus Matched Unrelated Donor versus Haploidentical Donor) on Outcomes after Clofarabine-Based Reduced-Intensity Conditioning Allograft for Myeloid Malignancies.

Clofarabine-based reduced-intensity conditioning (RIC) regimens are well-established schedules for allograft in patients with myeloid malignancies. A retrospective study was conducted including all adults allografted in our department with such a regimen and disease with the aim to assess whether or not the donor type (matched sibling [MSD], matched unrelated [MUD], or haploidentical [haplo]) impacted outcomes. Between October 2009 and February 2018, 118 patients met the inclusion criteria. Thirty-six, 55, and 27 patients received a graft from an MSD, MUD, or haplo donor, respectively. Peripheral blood stem cells (PBSCs) were the source of graft for all patients. The median age of the entire cohort was 62 years (range, 20 to 73), and the median follow-up was 31 months (range, 4.5 to 106). All patients engrafted except 1 haplo recipient. Neutrophils (>.5 × 109/L) and platelets (50 × 109/L) recoveries were significantly delayed in the haplo group (P = .0003 and P < .0001) compared with MSD and MUD. Acute grades II to IV or III to IV graft-versus-host disease (GVHD) incidences were similar between the 3 groups as well as the incidence of moderate or severe chronic GVHD. Also, similar 2-year overall survival (OS; 64.7% versus 73.9% versus 60.2%, P = .39), disease-free survival (DFS; 57.7% versus 70.9% versus and 53.6%, P = .1), and GVHD relapse-free survival (37.9% versus 54.3% versus 38.9%, P = .23) were observed between MSD versus MUD versus haplo groups. The same was true when considering only acute myeloid leukemia (AML) cases. In multivariate analysis the type of donor remained independent of outcomes in this series, whereas myelodysplastic syndrome (versus AML), high disease risk index, and older donor (≥50 years) were associated with lower OS and DFS. These data suggest that haplo donors are an acceptable alternative for patients receiving a clofarabine-based RIC PBSC allograft for myeloid malignancies who lack an MSD or a MUD.

FLT3 ligand plasma levels have no impact on outcomes after allotransplant in acute leukemia.

OBJECTIVE: This study was designed to assess the impact on outcomes of early soluble Fms-like tyrosine kinase 3 ligand concentrations (sFLc) in patients receiving an allogeneic hematopoietic stem cell transplantation (allo-HSCT) for acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). METHODS: This was a prospective monocentric study including all allo-HSCT patients included in the previous FLAM/FLAL study (Peterlin et al., 2019). Blood samples collected before the start of conditioning then post-transplant were frozen, stored and tested by ELISA. The parameters considered were hematopoietic recoveries, Leukemia Free Survival and Overall Survival, acute and chronic GVHD, grade 3 or 4 acute and/or extensive chronic GVHD-free and relapse-free survival (GRFS). RESULTS: Forty-one patients were included, a total of 179 samples were assayed for sFLc. There was no impact of sFLc levels (<=median vs> median) on acute and chronic GVHD incidences, LFS, OS nor GRFS. CONCLUSION: At variance with induction results for AML (Peterlin et al., 2019) endogenous sFLc do not appear to be a prognostic marker at the time of or after allo-HSCT. Even though the results are negatives, this is, to the best of our knowledge, the only prospective series specifically addressing the question of sFLc impact after allo-HSCT in acute leukemias.

Pomalidomide, cyclophosphamide, and dexamethasone for relapsed/refractory multiple myeloma patients in a real-life setting: a single-center retrospective study.

Pomalidomide dexamethasone is a standard of care for relapsed multiple myeloma (MM) patients who received at least two prior lines of therapy, including both lenalidomide and proteasome inhibitors (PI). We report here a real-life single-center series of 49 consecutive patients with relapsed and refractory MM treated with the triplet pomalidomide cyclophosphamide dexamethasone (PCD) combination. The median of prior lines of therapy was 3 and all patients were previously exposed to proteasome inhibitors and lenalidomide. The overall response rate was 76%, including 27% very good partial response or better. With a median follow-up of 16 months, the median progression-free survival (PFS) was 7.3 months and the median overall survival was not reached. Regarding safety, most frequent toxicity was hematologic, including 37% grade 3-4 cytopenias. Nine patients (18%) discontinued therapy due to adverse event. Our study confirms that PCD combination is feasible and results in favorable response rate and PFS in comparison with pomalidomide dexamethasone alone.

Single-agent daratumumab in very advanced relapsed and refractory multiple myeloma patients: a real-life single-center retrospective study.

The anti-CD38 monoclonal antibody daratumumab is approved as a single agent for the treatment of patients with relapsed and refractory multiple myeloma (RRMM) who have received at least three prior lines of therapy, including a proteasome inhibitor (PI) and an immunomodulatory agent (IMID), or who are double refractory to a PI and an IMID. To date, no real-life data on the efficacy and tolerance of daratumumab in this setting are available. We report here the results of a single-center series of 41 RRMM patients treated with single-agent daratumumab outside clinical trials. Patients received a median number of 4 prior therapies. All patients were previously exposed to PI and IMID and all patients were refractory to the last line of therapy. Most patients presented with high-risk characteristics, including 24% adverse cytogenetics (del17p/t(4,14)), 31% extramedullary disease and 12% circulating plasmacytosis at time of daratumumab therapy. The overall response rate was 24%, including 5% very good partial response or better. After a median follow-up of 6.5 months, all patients experienced disease relapse. The median progression-free survival was 1.9 months. At the time of disease progression, 44% of patients did not receive subsequent therapy. The median overall survival was 6.5 months. No new safety signal was identified. These real-life results revealed modest efficacy of single-agent daratumumab in advanced patients with RRMM in comparison with data from clinical trials.

Deauville Scores 4 or 5 Assessed by Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Early Post-Allotransplant Is Highly Predictive of Relapse in Lymphoma Patients.

The impact of early fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET-CT) status on survival after allogeneic transplantation for lymphoma is poorly reported. This retrospective study included all adult Hodgkin lymphoma (HL) or non-Hodgkin lymphoma(NHL) patients (>18 years old) who benefited from FDG PET-CT before (within 1 month) and/or early (+3 months and within +6 to 9 months) after allogeneic stem cell transplantation in our institution between 2005 and 2015 and who were still without documented progression or relapse at the time of the FDG PET-CT. All FDG PET-CT were reviewed by a nuclear medicine expert in hematology and restaged according to the Deauville scale. FDG-PET CT was considered positive when the uptake was higher than liver background (Deauville score ≥ 4). The primary objective was to study the impact of pre- and post-transplant FDG PET-CT on lymphoma-free survival (LFS) and overall survival (OS). Inclusion criteria were fulfilled for 103 patients (69 men; median age, 51.6 years old; range, 22 to 67). Diagnoses were high-grade NHL (n = 47), low-grade NHL (n = 6), T cell lymphoma (n = 34), and HL (n = 16). More than half of the patients were in complete remission at the time of transplant (n = 56). A reduced-intensity conditioning regimen was applied in most cases (n = 90). With a median follow-up of 49.5 months (range, 6 to 140.5) for alive patients, median 3-year OS and LFS were, respectively, 81% (range, 71% to 87%) and 65% (range, 54% to 74%) for the entire cohort. In multivariate analysis, positive FDG PET-CT at 3 months was the strongest independent factor significantly associated with poorer LFS (hazard ratio, 9.22; 95% confidence interval, 1.88 to 645.2; P = .006). FDG PET-CT positivity at 3 months appears to be highly predictive of LFS in patients after allogeneic transplantation and may help to guide strategies to prevent relapse. These results need to be validated prospectively.

p53 regulates CD46 expression and measles virus infection in myeloma cells.

In this study, we assessed the sensitivity of myeloma cells to the oncolytic measles virus (MV) in relation to p53 using 37 cell lines and 23 primary samples. We showed that infection and cell death were correlated with CD46 expression, which was associated with TP53 status; TP53 abn cell lines highly expressed CD46 and were preferentially infected by MV when compared with the TP53 wt cell lines (P = .046 and P = .045, respectively). Infection of myeloma cells was fully dependent on CD46 expression in both cell lines and primary cells. In the TP53 wt cell lines, but not the TP53 abn cell lines, activation of the p53 pathway with nutlin3a inhibited both CD46 expression and MV infection, while TP53 silencing reciprocally increased CD46 expression and MV infection. We showed using a p53 chromatin immunoprecipitation assay and microRNA assessment that CD46 gene expression was directly and indirectly regulated by p53. Primary myeloma cells overexpressed CD46 as compared with normal cells and were highly infected and killed by MV. CD46 expression and MV infection were inhibited by nutlin3a in primary p53-competent myeloma cells, but not in p53-deficient myeloma cells, and the latter were highly sensitive to MV infection. In summary, myeloma cells were highly sensitive to MV and infection inhibition by the p53 pathway was abrogated in p53-deficient myeloma cells. These results argue for an MV-based clinical trial for patients with p53 deficiency.

Clofarabine-based reduced intensity conditioning regimen with peripheral blood stem cell graft and post-transplant cyclophosphamide in adults with myeloid malignancies.

BACKGROUND: The Baltimore reduced-intensity conditioning (RIC) regimen using high-dose post-transplant cyclophosphamide (PTCY) is considered as a standard of care for haploidentical allogeneic stem cell transplantation (allo-SCT). However, it is associated with relatively low survivals and high incidence of relapse, especially when considering myeloid malignancies. RESULTS: This retrospective study included 36 adults (males n = 18; median age: 60.5 years old; haplodonors n = 27; matched donors n = 8) with myeloid malignancies transplanted between March 2014 and March 2017 at the University Hospital of Nantes. Very encouraging results were observed with a 18-month overall survival (OS), disease-free survival (DFS) and relapse incidence (RI) of 72% ± 7.5%, 63.8 ± 8%, and 25 ± 6% respectively, and a GVHD relapse-free survival (GRFS) of 52.6 ± 8%. In univariate analysis, there were no differences regarding 18-month survivals between patients allografted: i) for acute myeloid leukemia vs myelodysplastic syndrome (OS 70 ± 11% vs 69.2 ± 13%, p = 0.3; DFS 64.7 ± 11% vs 61.5 ± 13%, p = 0.65), or ii) with haplo-identical vs other donors (OS: 66.2 ± 9% vs 88.8 ± 10.4%, p = 0.16; DFS 59 ± 9.5% vs 77.8%, p = 0.6). CONCLUSION: The "Clo-Baltimore regimen" is safe and feasible and provides good survivals for patients with myeloid malignancies and haplo-donors. METHODS: Here, we report a variant of the Baltimore regimen, where 1) fludarabine was replaced by clofarabine, 2) bone marrow was replaced by peripheral blood stem cells, and 3) tacrolimus was replaced by cyclosporine, in a "Clo-Baltimore regimen".