Graft-versus-host disease and impact on relapse in myelofibrosis undergoing hematopoietic stem cell transplantation.

Allogeneic hematopoietic stem cell transplantation (alloHSCT) remains the only curative treatment for myelofibrosis (MF). Relapse occurs in 10-30% and remains a major factor for dismal outcomes. Previous work suggested that graft-versus-host disease (GVHD) might be associated with risk of relapse. This study included 341 patients undergoing their first (n = 308) or second (n = 33) alloHSCT. Anti-T-lymphocyte or antithymocyte globulin was used for GVHD prophylaxis in almost all patients. Median time to neutrophile and platelet engraftment was 13 days and 19 days, respectively. The cumulative incidence of acute GVHD grade II-IV was 41% (median, 31 days; range, 7-112). Grade III-IV acute GVHD was observed in 22%. The cumulative incidence of chronic GVHD was 61%. Liver was affected in 23% of acute GVHD cases and 46% of chronic GVHD cases. Severe acute GVHD was associated with high non-relapse mortality. The development of acute GVHD grade II and moderate GVHD was an independent factor for reduced risk for relapse after transplantation without increased risk for non-relapse mortality, while especially acute GVHD grade IV was associated with high non-relapse mortality. Last, we identified that ongoing response to ruxolitinib, accelerated-phase MF at time of transplantation and splenectomy prior to transplantation were independent predictors for relapse.

Development and Validation of a Concise Objectifiable Risk Evaluation Score for Non-Relapse Mortality after Allogeneic Hematopoietic Stem Cell Transplantation.

We aimed to develop a concise objectifiable risk evaluation (CORE) tool for predicting non-relapse mortality (NRM) and overall survival (OS) after allogeneic hematopoietic stem cell transplantation (allo-HCT). A total of 1120 adult patients who had undergone allo-HCT at our center between 2013 and 2020 were divided into training, first, and second validation cohorts. Objectifiable, patient-related factors impacting NRM in univariate and multivariate analyses were: serum albumin, serum creatinine, serum C-reactive protein (CRP), heart function (LVEF), lung function (VC, FEV1), and patient age. Hazard ratios were assigned points (0-3) based on their impact on NRM and summed to the individual CORE HCT score. The CORE HCT score stratified patients into three distinct low-, intermediate-, and high-risk groups with two-year NRM rates of 9%, 22%, and 46%, respectively, and OS rates of 73%, 55%, and 35%, respectively (p < 0.001). These findings were confirmed in a first and a second recently treated validation cohort. Importantly, the CORE HCT score remained informative across various conditioning intensities, disease-specific subgroups, and donor types, but did not impact relapse incidence. A comparison of CORE HCT vs. HCT Comorbidity Index (HCT-CI) in the second validation cohort revealed better performance of the CORE HCT score with c-statistics for NRM and OS of 0.666 (SE 0.05, p = 0.001) and 0.675 (SE 0.039, p < 0.001) vs. 0.431 (SE 0.057, p = 0.223) and 0.535 (SE 0.042, p = 0.411), respectively. The CORE HCT score is a concise and objectifiable risk evaluation tool for adult patients undergoing allo-HCT for malignant disease. External multicenter validation is underway.

Allogeneic hematopoetic stem cell transplant for patients with refractory T-Cell lymphomas.

OBJECTIVE: Allogeneic stem cell transplantation (allo-SCT) may have a curative potential due to the graft versus lymphoma effect. In this study, we aimed to compare transplant outcomes between refractory-T-NHL (ref-NHL) and Chemosensitive-T-NHL (CS-T-NHL). MATERIALS AND METHODS: We retrospectively reviewed the records of 26 ref-NHL and 29 CS-T-NHL consecutive patients who underwent allo-SCT at our center and compared the transplant outcomes between the groups. RESULTS: All patients were heavily pretreated with 27% of patients relapsing post-auto-SCT and two patients in the ref-T-NHL post-allo-SCT. Patients were transplanted mainly from unrelated donors. There were no differences in leucocytes and platelet engraftment between the two groups. At 3 years, the relapse incidence was 34% in Ref-TNHL and 19% in CS-TNHL (p = .33), with non-relapse mortality rates of 28% and 22%, respectively (p = .52). Female patients and those with a previous auto-SCT had lower relapse incidence (p = .045, p = .003). The 3-year overall survival was 39% in Ref-TNHL and 56% in CS-TNHL (p = .15). Trends for improved progression-free survival (PFS) and graft-versus-host disease relapse-free survival (GRFS) were observed in the CS-TNHL group (PFS: 60% vs. 30%, p = .075; GRFS: 38% vs. 21%, p = .1). CONCLUSION: Acknowledging the retrospective nature of our study, our results indicate that allo-SCT has a curative potential in patients with T-NHL even in refractory status.

Autologous-allogeneic versus autologous tandem stem cell transplantation and maintenance therapy with thalidomide for multiple myeloma patients less than 60 years of age: a prospective phase II study

The role of autologous-allogeneic tandem stem cell transplantation (alloTSCT) followed by maintenance as upfront treatment for multiple myeloma (MM) is controversial. Between 2008 and 2014 a total of 217 MM patients with a median age of 51 years were included by 20 German centers within an open-label, parallel-group, multi-center clinical trial to compare alloTSCT to auto tandem transplantation TSCT (autoTSCT) followed by a 2-year maintenance therapy with thalidomide (100 mg/d) in both arms with respect to relapse/progression-free survival (PFS) and other relevant outcomes. A total of 178 patients underwent second SCT (allo n = 132 and auto n = 46). PFS at 4 years after the second SCT was 47% (CI: 38-55%) for alloTSCT and 35% (CI: 21-49%) for autoTSCT (p = 0.26). This difference increased to 22% at 8 years (p = 0.10). The cumulative incidences of non-relapse mortality (NRM) and of relapse at 4 years were 13% (CI: 8-20%) and 2% (CI: 0.3-2%) (p = 0.044) and 40% (CI: 33-50%) and 63% (CI: 50-79%) for alloTSCT and autoTSCT (p = 0.04), respectively. The difference for relapse/progression increased to 33% (alloTSCT: 44%, autoTSCT: 77%) at a median follow-up of 82 months (p = 0.002). Four-year OS was 66% (CI: 57-73%) for alloTSCT and 66% (CI: 50-78%) for auto TSCT (p = 0.91) and 8-year OS was 52% and 50% (p = 0.87), respectively. AlloTSCT followed by thalidomide maintenance reduced the rate of recurrence or progression during a follow-up period of up to 10 years but failed to improve PFS significantly.

Use of ropeginterferon in inducing graft versus myelofibrosis effect in post-transplant myelofibrosis relapse.

Here, we describe a patient with post-transplant myelofibrosis with chronic graft-versus-host disease (GVHD), who showed successful molecular remission with ropeginterferon with 100% donor chimerism without any flare up of GVHD. He was initially diagnosed with polycythemia vera (PV) which progressed to myelofibrosis after 6 years. The MYSEC (Myelofibrosis Secondary to PV and ET-Prognostic Model) and MTSS (myelofibrosis transplant scoring system) scores were 13.1 and 4, respectively, and the patient was in intermediate risk group. He underwent an allogenic stem cell transplant; however, his disease gradually progressed and was administered two donor lymphocyte infusions with minimal response. A second allogeneic transplant was performed, which led to a persistent molecular remission for more than a decade, although he developed chronic skin graft-versus-host disease (GVHD). The JAK2 V617F levels started to increase 10 years post-transplant with ongoing chronic GVHD and a corresponding decrease in donor chimerism levels. He was administered ropeginterferon, which led to a decrease in JAK 2617F to undetectable levels. A graft versus myelofibrosis effect was attained with reversal to 100% donor chimerism, and he has since maintained a molecular remission with undetectable JAK 2617F levels. Chronic GVHD made him ineligible for donor lymphocyte infusions later. Thus, ropeginterferon was successful in inducing graft versus myelofibrosis effect, leading to a molecular response with no flare up of GVHD. The use of ropeginterferon needs to be further evaluated in larger cohorts of post-transplant myelofibrosis patients.

How I treat transplant-eligible patients with myelofibrosis.

Despite the approval of Janus kinase inhibitors and novel agents for patients with myelofibrosis (MF), disease-modifying responses remain limited, and hematopoietic stem cell transplantation (HSCT) remains the only potentially curative treatment option. The number of HSCTs for MF continues to increase worldwide, but its inherent therapy-related morbidity and mortality limit its use for many patients. Furthermore, patients with MF often present at an older age, with cytopenia, splenomegaly, and severe bone marrow fibrosis, posing challenges in managing them throughout the HSCT procedure. Although implementation of molecular analyses enabled improved understanding of disease mechanisms and subsequently sparked development of novel drugs with promising activity, prospective trials in the HSCT setting are often lacking, making an evidence-based decision process particularly difficult. To illustrate how we approach patients with MF with respect to HSCT, we present 3 different clinical scenarios to capture relevant aspects that influence our decision making regarding indication for, or against, HSCT. We describe how we perform HSCT according to different risk categories and, furthermore, discuss our up-to-date approach to reduce transplant-related complications. Last, we show how to harness graft-versus-MF effects, particularly in the posttransplant period to achieve the best possible outcomes for patients.

Donor Lymphocyte Infusion and Molecular Monitoring for Relapsed Myelofibrosis After Hematopoietic Cell Transplantation.

Hematopoietic cell transplantation (HCT) is a curative approach for myelofibrosis patients, but relapse is a major cause of treatment failure. We investigated the effect of donor lymphocyte infusion (DLI) in 37 patients with molecular (n = 17) or hematological relapse (n = 20) after HCT. Patients received median of 2 (range, 1-5) cumulative DLI (total of 91 infusions). Median starting dose was 1 × 106 cells/kg, escalated by half-log ≥6 weeks if no response nor graft-versus-host disease (GvHD) occurred. Median time to first DLI was 40 weeks for molecular relapse versus 145 weeks for hematological relapse. Overall molecular complete response (mCR) at any time was 73% (n = 27) and was significantly higher for initial molecular relapse (88%) versus hematological relapse (60%; P = 0.05). The 6-year overall survival was 77% versus 32% (P = 0.03). Acute GvHD 2-4 occurred in 22% and half of the patients achieved mCR without any GvHD. All patients who relapsed from mCR achieved after first DLI could be salvaged with subsequent DLI, showing long-term survival. No second HCT was needed for molecular relapse versus 6 for hematological relapse. This comprehensive and largest study to date suggests molecular monitoring together with DLI as standard of care and a crucial approach to achieve excellent outcomes in relapsed myelofibrosis.

Rapid development of cefiderocol resistance in a carbapenem-resistant Pseudomonas aeruginosa isolate associated with mutations in the pyoverdine biosynthesis pathway.

Here we report the in vivo development of cefiderocol resistance within 11 days after therapy initiation in a critically ill patient with bloodstream infection, infection of peri-anal fistula, and pneumonia caused by a VIM-2 harbouring, carbapenem-resistant Pseudomonas aeruginosa. Compared to a cefiderocol-naïve P. aeruginosa blood culture isolate, agar diffusion susceptibility testing found a reduced cefiderocol inhibition zone diameter in a P. aeruginosa recovered from peri-anal abscess tissue cultures after initiation of cefiderocol therapy. Subsequent whole-genome sequencing suggested that both isolates were of clonal origin. Comparison of genomes found an accumulation of missense mutations within pvdP, pvdE, pvdJ, and pvdD (i.e. genes associated with biosynthesis of pyoverdine), the main siderophore produced by P. aeruginosa. Quantification of pyoverdine production under iron-depleted conditions showed a significantly (P = 0.0003) higher pyoverdine production by the cefiderocol-resistant isolate. While pyoverdine quantity alone appears not to be decisive for cefiderocol resistance, the reported case highlights the potentially rapid emergence of cefiderocol resistance in P. aeruginosa and points towards a potential involvement of iron up-take systems in this process.

Spleen volume and length determined by computed tomography impact outcome after allogeneic stem cell transplantation for myelofibrosis.

Splenomegaly is a hallmark of myelofibrosis (MF), and reports on the impact of spleen size on the outcome of allo-HSCT have been conflicting, possibly due to differences in methods of assessment. We retrospectively analysed the impact of spleen volume and length measured by computed tomography on allo-HSCT outcome in 93 patients, 74% of whom had prior ruxolitinib treatment. Median spleen volume and length were 1.58 dm3 and 20 cm, respectively. We found a strong correlation between spleen volume and length (Pearson's r = 0.95, p < 0.001), Spearman (rho = 0.96, p < 0.001). After a median follow-up of 41.7 months, 5-year overall and disease-free survival were 66% and 59%, respectively. Spleen size did not impact overall survival or non-relapse mortality. Larger spleen volume and length as continuous variables were associated with slower platelet and leucocyte engraftment and a higher risk of disease relapse in univariate and multivariate analyses. Spleen length measured precisely by imaging is a good surrogate for spleen volume. In the era of JAK inhibitors, larger spleen size reflects advanced disease in MF and is associated with an increased risk of relapse but has no impact on non-relapse mortality and overall survival after allo-HSCT.

Impact of TP53 on outcome of patients with myelofibrosis undergoing hematopoietic stem cell transplantation.

TP53 mutations (TP53MTs) have been associated with poor outcomes in various hematologic malignancies, but no data exist regarding its role in patients with myelofibrosis undergoing hematopoietic stem cell transplantation (HSCT). Here, we took advantage of a large international multicenter cohort to evaluate the role of TP53MT in this setting. Among 349 included patients, 49 (13%) had detectable TP53MT, of whom 30 showed a multihit configuration. Median variant allele frequency was 20.3%. Cytogenetic risk was favorable (71%), unfavorable (23%), and very high (6%), with complex karyotype present in 36 patients (10%). Median survival of patients with TP53MT was 1.5 vs 13.5 years for those with wild-type TP53 (TP53WT; P < .001). Outcome was driven by multihit TP53MT constellation (P < .001), showing 6-year survival of 56% for individuals with single-hit vs 25% for those with multihit TP53MT vs 64% for those with TP53WT. Outcome was independent of current transplantation-specific risk factors and conditioning intensity. Similarly, cumulative incidence of relapse was 17% for single-hit vs 52% for multihit vs 21% for TP53WT. Ten patients with TP53MT (20%) presented as leukemic transformation vs only 7 (2%) in the TP53WT group (P < .001). Out of the 10 patients with TP53MT, 8 showed multihit constellation. Median time to leukemic transformation was shorter for multihit and single-hit TP53MT (0.7 and 0.5 years, respectively) vs 2.5 years for TP53WT. In summary, multihit TP53MT represents a very high-risk group in patients with myelofibrosis who are undergoing HSCT, whereas single-hit TP53MT alone showed similar outcome to patients with nonmutated TP53, informing prognostication for survival and relapse together with current transplantation-specific tools.

Iron Chelation with Deferasirox Suppresses the Appearance of Labile Plasma Iron During Conditioning Chemotherapy Prior to Allogeneic Stem Cell Transplantation.

During conditioning chemotherapy prior to allogeneic haematopoietic stem cell transplantation (HSCT), non-transferrin-bound iron and its chelatable form, labile plasma iron (LPI), regularly appear in the blood of patients at high levels of transferrin saturation (TfS). As these free iron species potentially favor infection and mediate transplantation-associated toxicities, chelation therapy could be an approach to improve outcome after transplantation. However, data addressing iron chelation in the immediate peritransplantation period are sparse. In this study, we investigated the influence of iron chelation with deferasirox during conditioning chemotherapy on the appearance of LPI, the incidence of infection and toxicities, and the tolerability of this treatment in the peritransplantation period. We conducted this single-center prospective observational study in 25 adults with iron overload (serum ferritin >1000 µg/L) undergoing allogeneic HSCT after myeloablative busulfan-based conditioning chemotherapy. Patients received iron chelation with deferasirox (14 mg/kg) from the start of conditioning until day 3 post-transplantation. Iron parameters, including LPI, were obtained at the chelator's trough level daily until day 0 and then on days 4, 7, and 14. Data on infection (bacteremia or invasive fungal disease) and toxicity, as well as the tolerability of deferasirox, were collected until the end of the follow-up period on day 28. Data were analyzed descriptively. TfS levels exceeded 70% in median on 6 days (range, 4 to 10 days) and in 63.6% (range, 36.4% to 90.9%) of the samples per patient, although in 19 of 25 patients (76%), no elevated LPI values were detected during the intake of deferasirox despite high TfS levels. Only 6 patients (24%) showed mildly increased LPI values (≤0.5 units) during the intake of deferasirox, 3 of whom had presented with elevated LPI values before the start of conditioning. Deferasirox was well tolerated, and no aggravation of toxicities was observed. Infection occurred in 5 patients (20%), including 3 of the 6 patients with elevated LPI values despite chelation therapy. In the present study, we demonstrate that iron chelation with deferasirox safely suppresses the appearance of LPI and might decrease the incidence of infection, whereas the impact on transplantation-associated toxicities remains to be elucidated.

Individualized busulfan dosing improves outcomes compared to fixed-dose administration in pre-transplant minimal residual disease-positive acute myeloid leukemia patients with intermediate-risk undergoing allogeneic stem cell transplantation in CR.

Pre-transplant minimal residual disease (MRD) impacts negatively on post-transplant relapse risk in acute myeloid leukemia (AML). Therapeutic drug monitoring by calculating area under the curve (AUC) was developed to optimize busulfan (Bu) exposure. Here, we compared post-transplant outcomes after individualized versus fixed busulfan dosage in intermediate-risk AML who achieved CR prior to allograft focusing on pre-transplant flow-MRD. Eighty-seven patients (median, 56 years) with intermediate-risk AML and pre-transplant flow-MRD ("different from normal") were included. Thirty-two patients received individualized busulfan; 54 fixed dosages. Individualized dosage was adjusted in 25/32 patients: increased, n = 18/25 (72%); decreased: n = 7/25 (28%). After median follow-up of 27 months, we observed lower 3-year relapses (6%, 2%-19% vs. 35%, 23%-49% p = 0.02), improved 3-year leukemia-free survival (LFS) (78%, 54%-91% vs. 55%, 40%-70% p = 0.009) and - overall survival (OS) (82%, 60%-93% vs. 69%, 54%-81% p = 0.05) after individualized compared to fixed Bu. Non-relapsed mortality (NRM) and acute graft versus host disease (GvHD) were not different. In multivariate analysis, fixed Bu showed unfavorable impact on OS (hazard ratio [HR] 4.6, p = 0.044), LFS (HR 3.6, p = 0.018) and relapses (HR 3.6, p = 0.033). Fixed Bu also had unfavorable impact on LFS (3.6, 1.1-12.6, p = 0.041) in pre-transplant MRD-positive patients. Individualized, AUC-based, busulfan is associated with lower relapses in intermediate-risk AML patients allografted in CR and may overcome pre-transplant MRD-positivity.

Molecular monitoring of T-cell kinetics and migration in severe neurotoxicity after real-world CD19-specific chimeric antigen receptor T cell therapy.

CD19-specific chimeric antigen receptor (CD19-CAR) T-cell therapies mediate durable responses in late-stage B-cell malignancies, but can be complicated by a potentially severe immune effector cell-associated neurotoxicity syndrome (ICANS). Despite broad efforts, the precise mechanisms of ICANS are not entirely known, and resistance to current ICANSdirected therapies (especially corticosteroids) has been observed. Recent data suggest that inflammatory cytokines and/or targeting of cerebral CD19-expressing pericytes can disrupt the blood-brain barrier and facilitate influx of immune cells, including CAR T cells. However, specific tools for CD19-CAR T-cell analysis within often minute samples of cerebrospinal fluid (CSF) are not broadly available. Here, we applied our recently developed digital polymerase chain reaction assays to monitor CD19-CAR T-cell kinetics in CSF and blood in real-world patients with neurotoxicity. Consistently, we observed a CAR T-cell enrichment within CSF in ICANS patients with further progressive accumulation despite intense corticosteroid- containing immuno-chemotherapies in a subset of patients with prolonged and therapy-resistant grade 3-4 neurotoxicity. We used next-generation T-cell receptor-b sequencing to assess the repertoire of treatment-refractory cells. Longitudinal analysis revealed a profound skewing of the T-cell receptor repertoire, which at least partly reflected selective expansion of infused T-cell clones. Interestingly, a major fraction of eventually dominating hyperexpanded T-cell clones were of non-CAR T-cell derivation. These findings hint to a role of therapy-refractory T-cell clones in severe ICANS development and prompt future systematic research to determine if CAR T cells may serve as 'door openers' and to further characterize both CAR-positive and non-CAR T cells to interrogate the transcriptional signature of these possibly pathologic T cells.

High Molecular and Cytogenetic Risk in Myelofibrosis Does Not Benefit From Higher Intensity Conditioning Before Hematopoietic Cell Transplantation: An International Collaborative Analysis.

There is no direct evidence to recommend specific conditioning intensities in myelofibrosis undergoing allogeneic hematopoietic cell transplantation, especially in the molecular era. We aimed to compare outcomes of reduced intensity (RIC) or myeloablative conditioning (MAC) transplantation in myelofibrosis with molecular information. The study included 645 genetically annotated patients (with at least driver mutation status available), of whom 414 received RIC and 231 patients received MAC. The median follow-up time from transplantation was 6.0 years for RIC and 9.4 years for MAC. The 6-year overall survival rates for RIC and MAC were 63% (95% confidence interval [CI], 58%-68%) and 59% (95% CI, 52%-66%; P = 0.34) and progression-free survival was 52% (95% CI, 47%-57%) and 52% (95% CI, 45%-59%; P = 0.64). The 2-year cumulative incidence of nonrelapse mortality was 26% (95% CI, 21%-31%) for RIC and 29% (95% CI, 23%-34%) for MAC (P = 0.51). In terms of progression/relapse, the 2-year cumulative incidence was 10% (95% CI, 5%-19%) for RIC and 9% (95% CI, 4%-14%) for MAC (P = 0.46). Higher intensity conditioning did not seem to improve outcomes for higher-risk disease, according to mutational, cytogenetic, and clinical profile. In contrast, patients with reduced performance status, matched unrelated donors, and ASXL1 mutations appeared to benefit from RIC in terms of overall survival.

Retrospective analysis of three induction chemotherapy regimens in acute myeloid leukemia including CPX-351, cytarabine/daunorubicin with and without the addition of cladribine.

Recently new treatments for acute myeloid leukemia (AML) emerged, including regimens like CPX-351 and cladribine with cytarabine and daunorubicin (DA + C), demonstrating improved survival in patient subsets. This retrospective analysis is comparing the outcome of 124 patients treated with cytarabine and daunorubicin (DA; n = 54), CPX-351 (n = 26) and DA + C (n = 44). Complete response rate following one cycle of therapy was increased in DA + C (62%) compared to CPX-351 (42%) and DA (50%). CPX-351 demonstrated a significant increased survival post allogenic stem cell transplantation against DA (hazard ratio (HR): 4.9; 95% confidence interval (95%CI): 1.1-21, p = 0.03). Median survival was reached for DA (5.6 years) but not for DA + C or CPX-351. Subgroup analysis showed that AML with myelodysplasia-related changes and therapy-related AML treated with CPX-351 had increased survival compared to DA (HR: 5.2; 95%CI: 1.2-22; p = 0.03). Our findings point twoards a CPX-351 superiority. However, the use of DA + C should be further evaluated in comparative studies.

Impact of Anti-T-lymphocyte globulin dosing on GVHD and Immune reconstitution in matched unrelated myeloablative peripheral blood stem cell transplantation.

Data on the influence of different Anti-lymphocyte globulin (ATLG) doses on graft versus host disease (GVHD) incidence and immune reconstitution in matched unrelated (MUD) allogeneic Stem cell transplantation (allo-SCT) is limited. This retrospective study conducted at the University Medical-Center Hamburg compares GVHD and Immune reconstitution after myeloablative MUD (HLA 10/10) PBSC allogeneic stem cell transplant between 30 mg/Kg (n = 73) and 60 mg/Kg (n = 216) ATLG. Detailed phenotypes of T, B natural killer (NK), natural killer T (NKT) cells were analyzed by multicolor flow at day 30, 100, and 180 posttransplant. Neutrophil and platelet engraftments were significantly delayed in the 60 mg/kg group with a higher Cumulative incidence of Infections (67% vs 75% p = 0.049) and EBV (21% vs 41% p = 0.049) reactivation at day 100 in this group. In the 30 mg/kg group, we observed a faster reconstitution of naïve-B cells (p < 0.0001) and γδ T cells (p = 0.045) at day+30 and a faster naïve helper T-cell (p = 0.046), NK-cells (p = 0.035), and naïve B-cell reconstitution (p = 0.009) at day+180. There were no significant differences in aGVHD, cGVHD, NRM, RI, PFS, and OS between the groups. The choice of ATLG dose has significant impact on IR but not on GVHD after MUD-allo-SCT. Higher doses are associated with delayed engraftment and increased infections.