Post-transplant-cyclophosphamide and short-term Everolimus as graft-versus-host-prophylaxis in patients with relapsed/refractory lymphoma and myeloma-Final results of the phase II OCTET-EVER trial

BACKGROUND

Conditioning regimens and the choice of immunosuppression have substantial impact on immune reconstitution after allogeneic hematopoietic stem cell transplantation (aHSCT). The pivotal mechanism to maintain remission is the induction of the graft-versus-tumor effect. Relapse as well as graft versus host disease remain common. Classic immunosuppressive strategies implementing calcineurin inhibitors (CNI) have significant toxicities, hamper the immune recovery, and reduce the anti-cancer immune response.

METHODS

We designed a phase II clinical trial for patients with relapsed and refractory lymphoid malignancies undergoing aHSCT using a CNI-free approach consisting of post-transplant cyclophosphamide (PTCy) and short-term Everolimus after reduced-intensity conditioning and matched peripheral blood stem cell transplantation. The results of the 19 planned patients are presented. Primary endpoint is the cumulative incidence and severity of acute GvHD.

RESULTS

Overall incidence of acute GvHD was 53% with no grade III or IV. Cumulative incidence of NRM at 1, 2, and 4 years was 11%, 11%, and 16%, respectively, with a median follow-up of 43 months. Cumulative incidence of relapse was 32%, 32%, and 42% at 1, 2, and 4 years after transplant, respectively. Four out of six early relapses were multiple myeloma patients. Overall survival was 79%, 74%, and 62% at 1, 2, and 4 years. GvHD-relapse-free-survival was 47% after 3 years.

CONCLUSIONS

Using PTCy and short-term Everolimus is safe with low rates of aGvHD and no severe aGvHD or cGvHD translating into a low rate of non-relapse mortality. Our results in this difficult to treat patient population are encouraging and warrant further studies.

Long-term remission in a patient with relapsed Richter's transformation treated with CD19-directed chimeric antigen-receptor T-cells after allogeneic stem cell transplantation

Patients with Richter's transformation of chronic lymphocytic leukemia (CLL) to diffuse large B-cell lymphoma (DLBCL-RT) face a dismal prognosis. A 51-year-old female patient diagnosed with CLL with deletion (17p) in 2009. CLL treatment included chemoimmunotherapy and targeted substances. DLBCL-RT was diagnosed in November 2016. After receiving an allogeneic hematopoietic stem cell transplantation, she relapsed in September 2019 and tisagenlecleucel was infused in December 2019. Cytokine release syndrome grade 2 was treated with two doses of tocilizumab and the patient was started on 140 mg ibrutinib in February 2020. Our patient remains in remission up to 4 years after CAR T-cell treatment.

Multiparametric Monitoring of Disease Progression in Contemporary Patients with Wild-Type Transthyretin Amyloid Cardiomyopathy Initiating Tafamidis Treatment

BACKGROUND

Recently, a disease modifying therapy has become available for transthyretin amyloid cardiomyopathy (ATTR-CM). A validated monitoring concept of treatment is lacking, but a current expert consensus recommends three clinical domains (clinical, biomarker and ECG/imaging) assessed by several measurable features to define disease progression.

METHODS

We retrospectively analyzed data of wild-type ATTR-CM patients initiating tafamidis therapy assessed within our local routine protocol at baseline and 6-months follow-up with respect to the frequency of values beyond the proposed thresholds defining disease progression. Additionally, associations of cardiac magnetic resonance (CMR) tomography with clinical domains were examined within a subgroup.

RESULTS

Sixty-two ATTR-CM patients were included (88.7% male, mean age 79 years). In total, 16.1% of patients had progress in the clinical and functional domain, 33.9% in the biomarker domain and 43.5% in the imaging/electrocardiography (ECG) domain, with the latter driven by deterioration of the diastolic dysfunction grade and global longitudinal strain. In total, 35.5% of patients showed progress in none, 35.5% in one, 29.0% in two and no patient in three domains, the latter indicating overall disease progression. A subgroup analysis of twenty-two patients with available baseline and follow-up CMR data revealed an increase in CMR-based extracellular volume by more than 5% in 18.2% of patients, with no significant correlation with progress in one of the clinical domains.

CONCLUSIONS

We provide first frequency estimates of the markers of disease progression according to a recent expert consensus statement, which might help refine the multiparametric monitoring concept in patients with ATTR-CM.

Clinical and Economic Burden Associated With Acute Graft-Versus-Host Disease After Allogeneic Hematopoietic Cell Transplantation in Germany

BACKGROUND

Acute graft-vs-host disease (aGVHD) is a serious complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT), yet there are limited data on the clinical and economic burden of aGVHD in Germany. This real-world study aimed to evaluate clinical and economic outcomes among patients in Germany with or without aGVHD after allo-HSCT.

METHODS

This retrospective cohort study used administrative claims extracted from the German statutory health insurance database. Eligible adult patients underwent allo-HSCT between 1 January 2009 and 31 December 2017 for any hematological malignancy. Clinical (severe infections and mortality) and economic (health care resource use [HCRU] and costs) outcomes were compared in "aGVHD" patients and "no GVHD" patients. Propensity score matching (1:1) was used to balance covariates between the aGVHD and no GVHD groups.

RESULTS

After propensity score matching, 95 aGVHD and 95 no GVHD patients were included in the analysis. The aGVHD group had significantly higher odds of mortality than the no GVHD group (odds ratio [OR] 2.2; 95% CI 1.2-4.0). Odds of severe infection were similar between the 2 groups (OR 1.7; 95% CI 0.9-3.3). Patients in the aGVHD group had significantly more overnight hospitalizations per patient-year (mean [SD]: 3.7 [3.0] and 2.7 [2.5], P = .029), and total direct costs were 1.6-fold higher than those in the no GVHD group.

CONCLUSION

Among patients who underwent allo-HSCT, aGVHD was associated with significantly higher mortality, HCRU, and costs, highlighting the need for effective prophylaxis and treatment options to prevent or reduce the incidence of aGVHD.

Torque teno virus-DNA load as individual cytomegalovirus risk assessment parameter upon allogeneic hematopoietic stem cell transplantation

BACKGROUND

Immune recovery following allogeneic hematopoietic stem cell transplantation (allo-HSCT) decisively influences the occurrence of opportunistic infections, one of the leading causes of death among this group of patients. Yet, today, there are no laboratory parameters mirroring immune function sufficiently. Torque teno virus (TTV) has already proven itself as a functional immune marker in other settings.

AIMS

In this analysis, we investigated whether monitoring of TTV-DNA load in whole blood is able to provide additional information on the capacity of the immune system to control cytomegalovirus (CMV) replication in allo-HSCT recipients.

METHODS

Whole blood samples from 59 patients were collected upon allo-HSCT (between Day -7 and +10), on Day +14, +21, +28, +56, +90, and +365 post-transplant. TTV-DNA loads and other relevant clinical information were correlated with the risk of CMV infections or reactivations, defined by evidence of viral replication in blood.

RESULTS

CMV serostatus of the recipient and a TTV load below 1000 copies/mL upon allo-HSCT were significantly associated with an increased incidence of CMV infection or reactivation.

CONCLUSIONS

Quantification of TTV load in the early phase of allo-HSCT procedure could provide additional information in order to identify patients at risk for CMV infection or reactivation.

Long-Term Survivors after Failure of Chimeric Antigen Receptor T Cell Therapy for Large B Cell Lymphoma: A Role for Allogeneic Hematopoietic Cell Transplantation? A German Lymphoma Alliance and German Registry for Stem Cell Transplantation Analysis

The outcome of patients with large B cell lymphoma (LBCL) who relapse or progress after CD19-directed chimeric antigen receptor T cell therapy (CAR-T) administered as salvage therapy beyond the second treatment line is poor. However, a minority of patients become long-term survivors despite CAR-T failure. The German Lymphoma Alliance (GLA) has proposed a hierarchical management algorithm for CAR-T failure in LBCL, aimed at allogeneic hematopoietic cell transplantation (alloHCT) as definite therapy in eligible patients. The purpose of this study was to investigate characteristics, relapse patterns, and management strategies in long-term survivors after CAR-T failure, with a particular focus on the feasibility and outcome of alloHCT. This was a retrospective analysis of all evaluable patients with a relapse/progression event (REL) observed in a previously reported GLA sample between November 2018 and May 2021. REL occurred in 214 of 356 patients (60%) who underwent CAR-T for LBCL in the previous GLA study. An evaluable dataset was available for 143 of these 214 patients (67%). Twenty-six of 143 patients (18%) survived 12 months or longer from REL, 109 (76%) died within the first year after REL, and 8 (6%) were alive but had not reached the 12-month landmark. Long-term survivors had more favorable pre-CAR-T features, had a longer interval between CAR-T and REL, and had more often received a tumor biopsy after CAR-T failure, whereas the choice of the first salvage regimen had no impact. AlloHCT was feasible in 40 of 53 patients (75%) intended and resulted in a 12-month post-transplantation overall survival of 36% in those patients who underwent transplantation with sensitive or untreated REL. AlloHCT after CAR-T failure in LBCL is feasible and may be an important contributor to long-term survival, although selection bias must be taken into account. Thus, alloHCT should be considered as a reasonable treatment option for eligible patients in this setting. However, because the overall outlook after CAR-T failure remains poor, novel effective therapeutic approaches are needed, either to allow long-term disease control per se or to improve the preconditions for successful alloHCT.

Real-world data suggest effectiveness of the allogeneic mesenchymal stromal cells preparation MSC-FFM in ruxolitinib-refractory acute graft-versus-host disease

BACKGROUND

Patients with steroid-refractory acute graft-versus-host disease (aGvHD) not tolerating/responding to ruxolitinib (RR-aGvHD) have a dismal prognosis.

METHODS

We retrospectively assessed real-world outcomes of RR-aGvHD treated with the random-donor allogeneic MSC preparation MSC-FFM, available via Hospital Exemption in Germany. MSC-FFM is provided as frozen cell dispersion for administration as i.v. infusion immediately after thawing, at a recommended dose of 1-2 million MSCs/kg body weight in 4 once-weekly doses. 156 patients, 33 thereof children, received MSC-FFM; 5% had Grade II, 40% had Grade III, and 54% had Grade IV aGvHD. Median (range) number of prior therapies was 4 (1-10) in adults and 7 (2-11) in children.

RESULTS

The safety profile of MSC-FFM was consistent with previous reports for MSC therapies in general and MSC-FFM specifically. The overall response rate at Day 28 was 46% (95% confidence interval [CI] 36-55%) in adults and 64% (45-80%) in children; most responses were durable. Probability of overall survival at 6, 12 and 24 months was 47% (38-56%), 35% (27-44%) and 30% (22-39%) for adults, and 59% (40-74%), 42% (24-58%) and 35% (19-53%) for children, respectively (whole cohort: median OS 5.8 months).

CONCLUSION

A recent real-world analysis of outcomes for 64 adult RR-aGvHD patients not treated with MSCs reports survival of 20%, 16% and 10% beyond 6, 12 and 24 months, respectively (median 28 days). Our data thus suggest effectiveness of MSC-FFM in RR-aGvHD.

Azacitidine, lenalidomide and donor lymphocyte infusions for relapse of myelodysplastic syndrome, acute myeloid leukemia and chronic myelomonocytic leukemia after allogeneic transplant: the Azalena-Trial

Azacitidine (Aza) combined with donor lymphocyte infusions (DLI) is an established treatment for relapse of myeloid malignancies after allogeneic transplantation. Based on its immunomodulatory and anti-leukemic properties we considered Lenalidomide (Lena) to act synergistically with Aza/DLI to improve outcome. We, therefore, prospectively investigated tolerability and efficacy of this combination as first salvage therapy for adults with post-transplant relapse of acute myeloid leukemia, myelodysplastic syndromes and chronic myelomonocytic leukemia. Patients were scheduled for eight cycles Aza (75 mg/m2 day 1-7), Lena (2.5 or 5 mg, days 1-21) and up to three DLI with increasing T-cell dosages (0.5×106-1.5×107 cells/kg). Primary endpoint was safety, while secondary endpoints included response, graft-versus-host disease (GvHD) and overall survival (OS). Fifty patients with molecular (52%) or hematological (48%) relapse of myelodysplastic syndromes (n=24), acute myeloid leukemia (n=23) or chronic myelomonocytic leukemia (n=3) received a median of seven (range, 1-8) cycles including 14 patients with 2.5 mg and 36 with 5 mg Lena daily dosage. Concomitantly, 34 patients (68%) received at least one DLI. Overall response rate was 56% and 25 patients (50%) achieved complete remission being durable in 80%. Median OS was 21 months and 1-year OS rate 65% with no impact of type of or time to relapse and Lena dosages. Treatment was well tolerated indicated by febrile neutropenia being the only grade ≥3 non-hematologic adverse event in >10% of patients and modest acute (grade 2-4 24%) and chronic (moderate/severe 28%) GvHD incidences. In summary, Lena can be safely added to Aza/DLI without excess of GvHD and toxicity. Its significant anti-leukemic activity suggests that this combination is a novel salvage option for post-transplant relapse (clinicaltrials gov. Identifier: NCT02472691).

Mobilization and Hematopoietic Stem Cell Collection in Poor Mobilizing Patients with Lymphoma: Final Results of the German OPTIMOB Study

Introduction

Successful mobilization and collection of peripheral hematopoietic stem cells (HSCs) are necessary for lymphoma patients eligible for myeloablative chemotherapy with subsequent autologous stem cell transplantation (ASCT). Albeit G-CSF alone or combined with chemotherapy is well-established methods for HSC mobilization, up to 40% of the patients fail to mobilize (poor mobilizer, PM). Plerixafor (PLX) is commonly used in PM patients resulting in increased migration of HSCs into peripheral blood and thus improves the collection outcome.

Methods

The prospective, multicenter, open-label, non-interventional OPTIMOB study assessed mobilization and collection parameter of patients with lymphoma or multiple myeloma to get deep insights in the treatment of those patients in clinical routine focusing on PM patients. PM was defined as follows: (1) no achievement of ≥20 CD34+ progenitor cells/µL before first apheresis, (2) PLX administration at any time point during the observational period, (3) reduction of the initially planned CD34+ progenitor cell yield as necessity due to failed mobilization or HSC collection, and (4) no performance of apheresis due to low CD34+ progenitor level. Primary objective of the study was to assess mobilization success by the proportion of PM patients achieving >2 × 106 CD34+ progenitor cells/kg body weight on the first day of apheresis. Here, the data of the lymphoma cohort are presented.

Results

Out of 238 patients with lymphoma documented in the study, 32% were classified as PM. 87% of them received PLX. Demographic data revealed no obvious differences between PM and good mobilizing (GM) patients. All patients were treated highly individualized prior to mobilization. Majority of all PM patients were able to undergo apheresis (95%) and reached their individual requested CD34+ progenitor cell target (72%). 57% of the PM patients achieved >2.0 × 106 CD34+ progenitor cells/kg body weight on day 1 of apheresis and nearby 70% of them underwent ASCT. Median time to engraftment was similar in PM and GM patients of the lymphoma cohort.

Conclusions

Majority of PM patients with lymphoma were successfully mobilized and underwent ASCT. Most of them received PLX during the study.

Developing a supportive and palliative care intervention for patients with allogeneic stem cell transplantation: protocol of a multicentre mixed-methods study (allo-PaS)

INTRODUCTION

Although allogeneic stem cell transplantation (allo-SCT) is a curative treatment for many haematological malignancies, it is often associated with a high morbidity and mortality. Yet, little is known about the needs for supportive and palliative care among allo-SCT recipients. Moreover, targeted interventions that reduce symptom burden and suffering are still lacking. The present study aims to inform a supportive-palliative care intervention for patients with allo-SCT and their informal carers by exploring their experience and assessing their needs, especially their existential concerns, regarding four research topics: symptom burden and quality of life; coexistence of a chance for cure and a relevant risk of dying; change in goals of care; dying phase.

METHODS AND ANALYSIS

This is a descriptive mixed-methods study in progress with a convergent parallel design. Data on the four research topics will be collected and analysed separately in three steps: (1) qualitative semi-structured interviews among 20 patients, 20 informal carers and 12 healthcare providers (HCPs) and focus groups among 12-24 HCPs; (2) a quantitative cross-sectional survey with validated questionnaires and self-developed questions among 100 patients, 100 informal carers and 50 HCPs; (3) a retrospective case analysis of all deceased patients who underwent an allo-SCT between 2010 and 2019, with collection of quantitative and qualitative data. The qualitative and quantitative data sets will be finally merged for comparison and interpretation. Results will serve to develop a supportive-palliative care intervention.

ETHICS AND DISSEMINATION

The Ethics Commission of the Faculty of Medicine of the University of Cologne approved this study (20-1370_2). The study results will be published in peer-review journals, be presented at congresses and will be translated into clinical practice through the development of the palliative-supportive care intervention.

TRIAL REGISTRATION NUMBER

DRKS00027290 (German Clinical Trials Register).

Inferior Outcomes of EU Versus US Patients Treated With CD19 CAR-T for Relapsed/Refractory Large B-cell Lymphoma: Association With Differences in Tumor Burden, Systemic Inflammation, Bridging Therapy Utilization, and CAR-T Product Use

Real-world evidence suggests a trend toward inferior survival of patients receiving CD19 chimeric antigen receptor (CAR) T-cell therapy in Europe (EU) and with tisagenlecleucel. The underlying logistic, patient- and disease-related reasons for these discrepancies remain poorly understood. In this multicenter retrospective observational study, we studied the patient-individual journey from CAR-T indication to infusion, baseline features, and survival outcomes in 374 patients treated with tisagenlecleucel (tisa-cel) or axicabtagene-ciloleucel (axi-cel) in EU and the United States (US). Compared with US patients, EU patients had prolonged indication-to-infusion intervals (66 versus 50 d; P < 0.001) and more commonly received intermediary therapies (holding and/or bridging therapy, 94% in EU versus 74% in US; P < 0.001). Baseline lactate dehydrogenase (LDH) (median 321 versus 271 U/L; P = 0.02) and ferritin levels (675 versus 425 ng/mL; P = 0.004) were significantly elevated in the EU cohort. Overall, we observed inferior survival in EU patients (median progression-free survival [PFS] 3.1 versus 9.2 months in US; P < 0.001) and with tisa-cel (3.2 versus 9.2 months with axi-cel; P < 0.001). On multivariate Lasso modeling, nonresponse to bridging, elevated ferritin, and increased C-reactive protein represented independent risks for treatment failure. Weighing these variables into a patient-individual risk balancer (high risk [HR] balancer), we found higher levels in EU versus US and tisa-cel versus axi-cel cohorts. Notably, superior PFS with axi-cel was exclusively evident in patients at low risk for progression (according to the HR balancer), but not in high-risk patients. These data demonstrate that inferior survival outcomes in EU patients are associated with longer time-to-infusion intervals, higher tumor burden/LDH levels, increased systemic inflammatory markers, and CAR-T product use.

Health Economic Aspects of Platelet Concentrates: Comparing Cost and Reimbursement of Pathogen Inactivated and Conventional Platelet Concentrates in a German Comprehensive Cancer Center

INTRODUCTION

Pathogen inactivation (PI) utilizing amotosalen and UVA light (INTERCEPT® Blood System) is a well-established method for the production of safer platelet concentrates (PCs). While many studies describe clinical and logistical benefits of PI, the implications and potential challenges from a hospital management perspective have not yet been analyzed - health economic analyses considering reimbursement of PI are lacking. The objective of this analysis was to examine the real-life inpatient treatment costs from a hospital perspective and to assess the economic impact of PI-PC versus conventional PC (CONV-PC) administration in Germany.

METHODS

Real-life cost data for inpatient cancer cases from 2020 of the University Hospital Cologne were identified by operating and procedure codes. The German diagnosis-related groups, extra fees, case mix index (CMI), length of stay (LOS), and average resource consumption of PC were evaluated from a micro-management perspective. The potential economic impact of implementing PI-treated PCs was modeled retrospectively.

RESULTS

In total, 951 inpatient cases were analyzed (CMI [median 4.7-9.9], LOS [median 26 days], number of cases in intensive care units [38%]). The median DRG fee was between EUR 13,800 and EUR 26,400. According to our model, the use of PI-PC compared to CONV-PC would result in savings between EUR 184 and EUR 306 per case.

CONCLUSION

From a hospital management perspective, oncological cases requiring PC transfusion are associated with a high CMI (reimbursement per DRG flat fee) and moderate costs with sufficient add-on payment for PI on a case level. Investment and process costs for PI implementation can be analyzed for site-specific scenarios.

Characterization and outcome of post-transplant lymphoproliferative disorders within a collaborative study

Background

Post-transplant lymphoproliferative disorders (PTLD) are heterogeneous lymphoid disorders ranging from indolent polyclonal proliferations to aggressive lymphomas that can arise after solid organ transplantation (SOT) and allogeneic hematopoietic transplantation (allo-HSCT).

Methods

In this multi-center retrospective study, we compare patient characteristics, therapies, and outcomes of PTLD after allo-HSCT and SOT. Twenty-five patients (15 after allo-HSCT and 10 after SOT) were identified who developed PTLD between 2008 and 2022.

Results

Median age (57 years; range, 29-74 years) and baseline characteristics were comparable between the two groups (allo-HSCT vs SOT), but median onset of PTLD was markedly shorter after allo-HSCT (2 months vs. 99 months, P<0.001). Treatment regimens were heterogeneous, with reduction of immunosuppression in combination with rituximab being the most common first-line treatment strategy in both cohorts (allo-HSCT: 66%; SOT: 80%). The overall response rate was lower in the allo-HSCT (67%) as compared to the SOT group (100%). Consequently, the overall survival (OS) trended towards a worse outcome for the allo-HSCT group (1-year OS: 54% vs. 78%; P=0.58). We identified PTLD onset ≤150 days in the allo-HSCT (P=0.046) and ECOG >2 in the SOT group (P=0.03) as prognostic factors for lower OS.

Conclusion

PTLD cases present heterogeneously and pose unique challenges after both types of allogeneic transplantation.

Motixafortide and G-CSF to mobilize hematopoietic stem cells for autologous transplantation in multiple myeloma: a randomized phase 3 trial

Autologous hematopoietic stem cell transplantation (ASCT) improves survival in multiple myeloma (MM). However, many individuals are unable to collect optimal CD34+ hematopoietic stem and progenitor cell (HSPC) numbers with granulocyte colony-stimulating factor (G-CSF) mobilization. Motixafortide is a novel cyclic-peptide CXCR4 inhibitor with extended in vivo activity. The GENESIS trial was a prospective, phase 3, double-blind, placebo-controlled, multicenter study with the objective of assessing the superiority of motixafortide + G-CSF over placebo + G-CSF to mobilize HSPCs for ASCT in MM. The primary endpoint was the proportion of patients collecting ≥6 × 106 CD34+ cells kg-1 within two apheresis procedures; the secondary endpoint was to achieve this goal in one apheresis. A total of 122 adult patients with MM undergoing ASCT were enrolled at 18 sites across five countries and randomized (2:1) to motixafortide + G-CSF or placebo + G-CSF for HSPC mobilization. Motixafortide + G-CSF enabled 92.5% to successfully meet the primary endpoint versus 26.2% with placebo + G-CSF (odds ratio (OR) 53.3, 95% confidence interval (CI) 14.12-201.33, P < 0.0001). Motixafortide + G-CSF also enabled 88.8% to meet the secondary endpoint versus 9.5% with placebo + G-CSF (OR 118.0, 95% CI 25.36-549.35, P < 0.0001). Motixafortide + G-CSF was safe and well tolerated, with the most common treatment-emergent adverse events observed being transient, grade 1/2 injection site reactions (pain, 50%; erythema, 27.5%; pruritis, 21.3%). In conclusion, motixafortide + G-CSF mobilized significantly greater CD34+ HSPC numbers within two apheresis procedures versus placebo + G-CSF while preferentially mobilizing increased numbers of immunophenotypically and transcriptionally primitive HSPCs. Trial Registration: ClinicalTrials.gov , NCT03246529.

CMV-IgG pre-allogeneic hematopoietic stem cell transplantation and the risk for CMV reactivation and mortality

Cytomegalovirus (CMV) represents one of the most common infectious complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Currently, a common diagnostic test used to stratify the risk for CMV infection in allo-HSCT recipients is the qualitative CMV serology of donor and recipient. A positive serostatus of the recipient is the most important risk factor for CMV reactivation and associated with reduced overall survival post-transplantation (TX). Direct and indirect effects of CMV are involved in the poorer survival outcome. The present study investigated if the quantitative interpretation of anti-CMV IgG before allo-HSCT might serve as a novel parameter for the identification of patients at risk for CMV reactivation and worse outcome post-TX. For this purpose, a cohort of 440 allo-HSCT recipients over a period of 10 years was retrospectively analyzed. Our findings indicated that patients with high CMV IgG pre-allo-HSCT had a higher risk to develop CMV reactivation, including clinically relevant infections, and a worse prognosis 36 months post-allo-HSCT as compared to recipients with low CMV IgG values. In the letermovir (LMV) era, this group of patients might benefit from a closer CMV monitoring, and hence, earlier intervention if needed, especially after discontinuation of prophylaxis.

LONG-TERM FOLLOW-UP OF ASYMMETRIC BILATERAL DIFFUSE UVEAL MELANOCYTIC PROLIFERATION IN A PATIENT WITH METASTASIZED UROTHELIAL CARCINOMA

PURPOSE

To report a case of bilateral diffuse uveal melanocytic proliferation over 30 months follow-up.

METHODS

Multimodal imaging including ultra-wide-field color fundus photography, blue light fundus autofluorescence, swept-source optical coherence tomography, fluorescein angiography, and indocyanine green angiography.

RESULTS

A 49-year-old woman presented with decreased vision 2 months after bladder cancer surgery. Exudative retinal detachment and leopard spot pattern chorioretinopathy were observed in the right eye. Chemotherapy and cystectomy were initiated. Progressive bilateral vision loss occurred with melanocytic proliferation, choroidal thickening, subretinal fibrosis, fluid extravasation, rapid development of mature cataract, multiple iris cysts, and rubeosis, despite plasmapheresis and IV immunoglobulins. After cataract surgery, massive fibrin reaction resulted in a ciliolenticular block. One year later, positron emission tomography-computed tomography revealed absence of metastases. At Month 23, choroidal thickness increased in line with tumor progression. Palliative systemic therapy was initiated. Secondary macular neovascularization was treated with intravitreal antivascular endothelial growth factor injections. Visual acuity was light perception in the right eye and 20/200 in the left eye at last follow-up.

CONCLUSION

Bilateral diffuse uveal melanocytic proliferation results in progressive melanocyte proliferation and exudation, leading to severe visual loss. In our case, visual acuity was preserved at a low level in one eye under continuous systemic treatment. Systemic corticosteroids are recommended for cataract surgery in the setting of bilateral diffuse uveal melanocytic proliferation to prevent massive fibrin reaction. Intravitreal antivascular endothelial growth factor injections may be indicated if secondary macular neovascularization develops.

Characteristics and outcomes of patients undergoing high-dose chemotherapy and autologous stem cell transplantation admitted to the intensive care unit: a single-center retrospective analysis

High-dose chemotherapy and autologous stem cell transplantation (ASCT) can be associated with adverse events necessitating treatment on the intensive care unit (ICU). Data focusing on patients admitted to the ICU during hospitalization for high-dose chemotherapy and ASCT are scarce. We thus conducted a single-center retrospective analysis comprising 79 individuals who had high-dose chemotherapy and ASCT between 2014 and 2020 and were admitted to the ICU between the initiation of conditioning therapy and day 30 after ASCT. The median age was 57 years (range: 20-82 years); 38% of patients were female. B-cell non-Hodgkin lymphoma (34%) and plasma cell disorders (28%) were the most common indications for high-dose chemotherapy and ASCT. Sepsis represented the major cause for ICU admission (68%). Twenty-nine percent of patients required mechanical ventilation (MV), 5% had renal replacement therapy, and 44% needed vasopressors. The ICU, hospital, 90-day, and 1-year survival rates were 77.2%, 77.2%, 72.2%, and 60.3%, respectively. Stable disease or disease progression prior to the initiation of high-dose chemotherapy (p = 0.0028) and MV (p < 0.0001) were associated with an impaired survival. A total of 36 patients died during observation. The most frequent causes of death were the underlying malignancy (44%) and sepsis (39%). Taken together, the present analysis indicates a favorable overall outcome for patients admitted to the ICU during hospitalization for high-dose chemotherapy and ASCT. Thus, this patient group should not be denied admission and treatment on the ICU.

Mocravimod, a Selective Sphingosine-1-Phosphate Receptor Modulator, in Allogeneic Hematopoietic Stem Cell Transplantation for Malignancy

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) remains the sole curative option for patients with acute myelogenous leukemia. Outcomes are limited by leukemia relapse, graft-versus-host disease (GVHD), and abnormal immune reconstitution. Mocravimod (KRP203) is an oral sphingosine-1-phosphate receptor (S1PR) modulator that blocks the signal required by T cells to egress from lymph nodes and other lymphoid organs. Mocravimod retains T cell effector function, a main differentiator to immunosuppressants. In preclinical models, mocravimod improves survival by maintaining graft-versus-leukemia (GVL) activity while reducing GVHD. In patients undergoing allo-HSCT for hematological malignancies, mocravimod is postulated to prevent GVHD by redistributing allogeneic donor T cells to lymphoid tissues while allowing a sufficient GVL effect in the lymphoid, where malignant cells usually reside. The primary objective of this study was to assess the safety and tolerability of mocravimod in patients undergoing allo-HSCT for hematologic malignancies. Secondary objectives were to determine the pharmacokinetic profiles of mocravimod and its active metabolite mocravimod-phosphate in this patient group, as well as to assess GVHD-free, relapse free survival at 6 months after the last treatment. In this 2-part, single- and 2-arm randomized, open-label trial, we evaluated the safety, tolerability, and pharmacokinetics of mocravimod in allo-HSCT recipients (ClinicalTrials.gov identifier NCT01830010). Patients received either 1 mg or 3 mg mocravimod per day on top of standard of care GVHD prophylaxis with either cyclosporine A/methotrexate or tacrolimus/methotrexate. We found that mocravimod can be safely added to standard treatment regimens in patients with hematologic malignancies requiring allo-HSCT. Mocravimod resulted in a significant reduction of circulating lymphocyte numbers and had no negative impact on engraftment and transplantation outcomes. Our results indicate that mocravimod is safe and support a larger study to investigate its efficacy in a homogeneous acute myelogenous leukemia patient population undergoing allo-HSCT.

Salvage High-dose Melphalan With Autologous Stem cell Transplantation as Bridge to Consolidation Therapy for Chemoresistant Aggressive B-cell Lymphoma

BACKGROUND

Patients suffering from refractory aggressive B-cell lymphoma not responding to salvage chemotherapy have a dismal prognosis. CAR T-cells or allogeneic stem cell transplantation (SCT) are potentially curative approaches. However, obtaining a remission, and lowering tumor burden before consolidation seems crucial for long-term efficacy of both treatment modalities.

MATERIALS AND METHODS

In this retrospective analysis, we reviewed patients with chemoresistant aggressive B-cell lymphoma, defined as being refractory or progressive to at least second line salvage chemotherapy including the regimen immediately preceding autologous stem cell transplantation (ASCT), treated at 2 tertiary centers, who were eligible for intensive treatment using single agent high-dose (HD) melphalan to obtain a remission before consolidating therapy.

RESULTS

We identified 36 patients that received single agent HD melphalan and ASCT as remission induction followed by CAR T-cells or allogeneic stem cell transplantation (SCT). Thirteen of the evaluable patients (39.4%) achieved a partial remission and 9 patients (27.73%) a complete remission, resulting in an overall response rate (ORR) of 66.7%. High remission rates were seen across all subgroups including patients with primary refractory lymphoma (ORR 58.3%), uncontrolled disease and high tumor burden as indicated by increased LDH levels (ORR 66.7% for patients with elevated LDH above 2 times upper limit of norm). 22 patients proceeded to allogeneic SCT and 5 to CAR T-cell therapy. Treatment related mortality of ASCT was 5.5% (2 patients, both due to infections). Two-year overall survival of all patients was 15.8%, primarily due to a high non-relapse mortality (45.5%) of allogeneic SCT patients treated with myeloablative conditioning chemotherapy.

CONCLUSION

Single agent HD melphalan produces high remission rates in patients with chemoresistant, uncontrolled aggressive B-cell lymphoma and provides a window of opportunity for consolidation therapy.

MICROABSTRACT

Patient with refractory/relapsed aggressive B-cell lymphoma after salvage therapy are an unmet medical need because of their very poor prognosis. In our retrospective analysis of 36 patients we showed that single agent high-dose melphalan can achieve high response rates (ORR 66.7%) even in uncontrolled disease enabling consolidation therapy e.g. with allogeneic stem cell transplantation or CAR T-cell therapy.

High mortality of COVID-19 early after allogeneic stem cell transplantation – a retrospective multicenter analysis on behalf of the German Cooperative Transplant Study Group

Recipients of allogeneic stem cell transplantation (alloSCT) are at high risk for contracting infectious diseases with high morbidity and mortality. Coronavirus disease 2019 (COVID-19) is a viral respiratory disease that can lead to severe pneumonia and acute respiratory distress syndrome, with a potentially fatal outcome. In this retrospective study conducted on behalf of the German Cooperative Transplant Study Group, we aimed to analyze risk factors, disease course, and outcomes of COVID-19 in patients who underwent alloSCT. AlloSCT recipients who became infected with SARS-CoV-2 at German and Austrian transplant centers between February 2020 and July 2021 were included. Classification of COVID-19 severity into mild, moderate-severe, or critical disease and division of the course of the pandemic into 4 phases were done according to the German Robert Koch Institute. The main endpoint was overall mortality at the end of follow-up. We further analyzed the need for treatment in an intensive care unit (ICU) and the severity of disease. Risk factors were evaluated using univariate and multivariate analyses, and survival analysis was performed using Kaplan-Meier method. The study cohort comprised 130 patients from 14 transplant centers, with a median age at diagnosis of COVID-19 of 59 years (range, 20 to 81 years) and a median interval between alloSCT and COVID-19 of 787 days (range, 19 to 8138 days). The most common underlying diseases were acute myeloid leukemia (45.4%) and lymphoma (10.8%). The majority of patients (84.9%) were infected in the later phases of the pandemic; 20.8% had moderate-severe disease, 12.3% had critical disease, and 19.2% were treated in an ICU. After a median follow-up of 127 days, overall mortality was 16.2%, 52.0% among patients treated in an ICU. Risk factors for mortality in multivariate analysis were active disease (odds ratio [OR], 4.46), infection with SARS-CoV-2 ≤365 days after alloSCT (OR, 5.60), age >60 years (OR, 5.39), and ongoing immunosuppression with cyclosporine (OR, 8.55). Risk factors for developing moderate-severe or critical disease were concurrent immunosuppression (OR, 4.06) and age >40 years (OR, 4.08). Patients after alloSCT exhibit a substantially increased mortality risk after COVID-19 infection compared with the normal population, without considerable improvement over the course of the pandemic. Risk factors include age, early infection post-alloSCT, and active immunosuppression. Further studies are needed to improve prevention and treatment in this high-risk patient group.

Combined Therapy with Intravenous Immunoglobulins, Letermovir and (Val-)Ganciclovir in Complicated Courses of CMV-Infection in Transplant Recipients

The treatment options for cytomegalovirus (CMV) infections in immunosuppressed patients are limited, mainly consisting of (val-)ganciclovir (VGC/GCV) as the first-line treatment. We report on three transplant recipients, one stem cell transplant (allo-HSCT) patient and two kidney transplant (KTx) recipients, with prolonged CMV viremia treated with a combined therapy based on letermovir (LMV), CMV-specific intravenous immunoglobulins (IVIg), and VGC/GCV, which led to the sustained control of CMV viremia in all patients.

Polatuzumab vedotin as a salvage and bridging treatment in relapsed or refractory large B-cell lymphomas

The antibody-drug conjugate polatuzumab vedotin (pola) has recently been approved in combination with bendamustine and rituximab (pola-BR) for patients with refractory or relapsed (r/r) large B-cell lymphoma (LBCL). To investigate the efficacy of pola-BR in a real-world setting, we retrospectively analyzed 105 patients with LBCL who were treated in 26 German centers under the national compassionate use program. Fifty-four patients received pola as a salvage treatment and 51 patients were treated with pola with the intention to bridge to chimeric antigen receptor (CAR) T-cell therapy (n = 41) or allogeneic hematopoietic cell transplantation (n = 10). Notably, patients in the salvage and bridging cohort had received a median of 3 prior treatment lines. In the salvage cohort, the best overall response rate was 48.1%. The 6-month progression-free survival and overall survival (OS) was 27.7% and 49.6%, respectively. In the bridging cohort, 51.2% of patients could be successfully bridged with pola to the intended CAR T-cell therapy. The combination of pola bridging and successful CAR T-cell therapy resulted in a 6-month OS of 77.9% calculated from pola initiation. Pola vedotin-rituximab without a chemotherapy backbone demonstrated encouraging overall response rates up to 40%, highlighting both an appropriate alternative for patients unsuitable for chemotherapy and a new treatment option for bridging before leukapheresis in patients intended for CAR T-cell therapy. Furthermore, 7 of 12 patients with previous failure of CAR T-cell therapy responded to a pola-containing regimen. These findings suggest that pola may serve as effective salvage and bridging treatment of r/r LBCL patients.

Selective ABO immunoadsorption in hematopoietic stem cell transplantation with major ABO incompatibility

OBJECTIVE

ABO mismatch between donor and recipient occurs in 40% of allogeneic hematopoietic stem cell transplantations (HCT). Different strategies have been described to reduce isohemagglutinins (IHA) before HCT. We describe the effect of selective ABO immunoadsorption (ABO IA) on erythrocyte transfusion rate and the development of post-transplant pure red cell aplasia (ptPRCA).

METHODS

63 patients with major ABO incompatibility were retrospectively analyzed. Nine patients with major ABO incompatibility and high-IHA titer were treated by ABO IA before HCT. We analyzed the need for transfusion and the occurrence of ptPRCA. We compared the outcome with patients treated by other methods to reduce IHA.

RESULTS

In all nine patients treated by ABO IA, IHA decreased in a median four times. PtPRCA occurred in one patient. The median number of transfusions was 8 (range: 0-36) between d0 and d100. In 25 patients with high-IHA titer without treatment or treated by other methods to reduce IHA, the need for transfusions was comparable. No difference in the incidence of ptPRCA was observed.

CONCLUSIONS

Selective ABO IA is a feasible, safe, and effective method to reduce IHA before HCT in major ABO incompatibility. No effect on transfusion rate or ptPRCA compared to other strategies could be observed.

Detection of systemic immunosuppressants in autologous serum eye drops (ASED) in patients with severe chronic ocular graft versus host disease

PURPOSE

Chronic graft versus host disease is a major consequence after allogeneic stem cell transplantation (allo-SCT) and has great impact on patients' morbidity and mortality. Besides the skin, liver, and intestines, the eyes are most commonly affected, manifesting as severe ocular surface disease. Treatment protocols include topical steroids, cyclosporine, tacrolimus, and ASED. Since these patients often receive systemic immunosuppressant therapy from their oncologists, a topical re-administration of these drugs via ASED with potentially beneficial or harmful effects is possible. The purpose of the study was to determine whether and to which extent systemic immunosuppressants are detectable in ASED.

METHODS

A total of 34 samples of ASED from 16 patients with hemato-oncological malignancies after allo-SCT were collected during the manufacturing process and screened for levels of cyclosporine, mycophenolic acid, everolimus, and tacrolimus via liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The study followed the tenets of the Declaration of Helsinki and informed consent was obtained from the subjects after explanation of the nature and possible consequences of the study.

RESULTS

Cyclosporine was found in 18 ASED samples in concentrations ranging from 6.5-105.0 ng/ml (32.0 ± 22.8 ng/ml, mean ± SD). The concentration range of mycophenolic acid in 19 samples was 0.04-25.0 mg/l (4.0 ± 5.4 mg/l, mean ± SD). Everolimus and tacrolimus concentrations were well below the respective limits of quantification (< 0.6 and < 0.5 ng/ml) of the established LC-MS/MS method in all samples.

CONCLUSIONS

Our study suggests that orally administered cyclosporine and mycophenolic acid for the treatment of systemic GvHD, but not everolimus and tacrolimus, are distinctly detectable in ASED in relevant concentrations. It is highly likely that these agents affect topical therapy of ocular GvHD. However, the extent of this effect needs to be evaluated in further studies.

Restriction of HIV-1 Escape by a Highly Broad and Potent Neutralizing Antibody

Broadly neutralizing antibodies (bNAbs) represent a promising approach to prevent and treat HIV-1 infection. However, viral escape through mutation of the HIV-1 envelope glycoprotein (Env) limits clinical applications. Here we describe 1-18, a new V_H1-46-encoded CD4 binding site (CD4bs) bNAb with outstanding breadth (97%) and potency (GeoMean IC₅₀ = 0.048 μg/mL). Notably, 1-18 is not susceptible to typical CD4bs escape mutations and effectively overcomes HIV-1 resistance to other CD4bs bNAbs. Moreover, mutational antigenic profiling uncovered restricted pathways of HIV-1 escape. Of most promise for therapeutic use, even 1-18 alone fully suppressed viremia in HIV-1-infected humanized mice without selecting for resistant viral variants. A 2.5-Å cryo-EM structure of a 1-18-BG505_SOSIP.664 Env complex revealed that these characteristics are likely facilitated by a heavy-chain insertion and increased inter-protomer contacts. The ability of 1-18 to effectively restrict HIV-1 escape pathways provides a new option to successfully prevent and treat HIV-1 infection.

Bridging antifungal prophylaxis with 50 mg or 100 mg micafungin in allogeneic stem cell transplantation: A retrospective analysis

OBJECTIVE

Fluconazole or posaconazole is a standard of care in antifungal prophylaxis for patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). However, many patients need to interrupt standard prophylaxis due to intolerability, drug-drug interactions, or toxicity. Micafungin has come to prominence for these patients. However, the optimal biological dose of micafungin stays unclear.

METHODS

We retrospectively evaluated the efficacy of micafungin as antifungal prophylaxis in HSCT patients. Micafungin was applied as bridging in patients who were not eligible to receive oral posaconazole. Micafungin was either given at a dose of 100 mg or 50 mg SID.

RESULTS

A total of 173 patients received micafungin prophylaxis, 62 in the 100 mg and 111 in the 50 mg dose group. The incidence of probable or proven breakthrough IFDs during the observation period was one in the 100 mg and one in the 50 mg group. Fungal-free survival after 100 days was 98% and 99% (P = .842), and overall survival after 365 days was 60% and 63% (P = .8) respectively. In both groups, micafungin was well tolerated with no grade 3 or 4 toxicities.

CONCLUSION

In this retrospective analysis, which was not powered to detect non-inferiority, micafungin is effective and complements posaconazole as fungal prophylaxis in HSCT.

224. Epidemiology of Bloodstream infections in a Cohort of Allogeneic Hematopoietic Stem Cell Transplant Patients from 2009 to 2018

Background

Due to severe immunosuppression, patients undergoing allogeneic hematopoietic stem cell transplantation (aSCT) are at increased risk of infection and especially bloodstream infections (BSI) remain a major cause of death. Knowledge of the specific epidemiology of pathogens and resistances is of utmost importance to optimize antimicrobial treatment strategies.

Methods

Based on the Cologne Cohort of Neutropenic Patients (CoCoNut) database, we conducted a retrospective analysis of blood cultures collected within 100 days following transplantation of patients undergoing aSCT between January 2009 and December 2018 at the University Hospital of Cologne, Germany. Contamination of coagulase-negative Staphylococci (CoNS) isolates (single positive isolate within 5 days) was considered within the analysis.

Results

In total, 843 aSCT patients were available for analysis (484/843 [57%] male). The median age was 53 (interquartile range [IQR] 43–62) years, predominant underlying diseases were acute myeloid leukemia (47%, 397/843), lymphoma (14%, 117/843), and acute lymphoblastic leukemia (11%, 89/843). Median inpatient stay was 39 (IQR 34–50) days, while 67/843 (8%) patients died. Antibacterial prophylaxis was administered in 289/843 (34%) and antifungal prophylaxis in 738/843 (88%) patients. BSI was diagnosed in 233/843 (28%) patients. In total, 5,489 pairs of blood cultures were taken (median 4 per patient, IQR 2–8), while a pathogen could only be detected in 922/5,489 (17%). Most frequent pathogens were CoNS (259/922, 28%), Enterococcus spp. (219/922, 24%), E. coli (132/922, 14%), Klebsiella spp. (44/922, 5%), P. aeruginosa (39/922, 4%), S. aureus (37/922, 4%), and Candida spp. (42/922, 5%). Polymicrobial infection was detected in 58/922 (6%) cases. Within Enterococci isolates, 24/219 (11%) were VRE. None of the Klebsiella, but 9/132 (7%) of E. coli isolates were ESBL positive. In 4/37 (11%) cases S. aureus isolates were MRSA.

Conclusion

Patients in the early phase after aSCT are at high risk of BSI with a predominantly gram-positive spectrum. Empirical antimicrobial treatment must consider pathogen epidemiology and resistance patterns while waiting for blood culture results.

Disclosures

All authors: No reported disclosures.

2474. The 10 Years Scientific Contribution of the Cologne Cohort of Neutropenic Patients (CoCoNut) for Evaluating Treatment and Outcome of Healthcare-associated Infections

Background

Healthcare-associated infections (HAIs) are a leading cause for morbidity and mortality in neutropenic patients.

Methods

The Cologne Cohort of Neutropenic Patients (CoCoNut) is an ongoing, prospective, longitudinal cohort, collecting inpatient data for analysis of epidemiology, risk factors, and outcome of neutropenic patients (at least one day of absolute neutrophil count < 500/µL) at risk for HAIs. The CoCoNut contains comprehensive data, i.e. patient characteristics, medication, chemotherapy, clinical data (e.g., diarrhea, body temperature), as well as laboratory, microbiological, virologic, and radiological results. The purpose of this cohort is to improve the knowledge on HAIs and management of anti-infective prophylaxis and therapy.

Results

To date, the CoCoNut includes 8,176 inpatient stays from 3,354 neutropenic patients treated at the hematology/oncology department of the University Hospital of Cologne between January 2009 and December 2018. Hodgkin and Non-Hodgkin lymphoma (32%), acute leukemia (28%), and chronic leukemia (10%) were the predominant underlying diseases; comprising 843/8,176 (10%) inpatient stays with allogenic stem cell transplantation. The overall number of neutropenic days and fever days (body temperature ≥ 38 °C) was 56,824 and 25,347, respectively. Blood stream infections (occurrence of fever and positive blood culture) occurred in 1,283/8,176 (16%) inpatient stays, and the overall mortality rate was 9% (n = 716/8,176). By now, 17 peer-reviewed articles analyzing epidemiology, treatment, and outcome of HAIs were published based on data from the CoCoNut.

Conclusion

Data extracted from the CoCoNut underlines the important role of evaluating innovative treatment strategies. Considering the remaining high infection rate for HAIs of neutropenic patients, the growing development of antimicrobial drug resistance, and the existing powerful methods for data processing (e.g., artificial intelligence), we will continue to utilizing and expanding the CoCoNut in the future.

Disclosures

All authors: No reported disclosures.

Sequential therapy for patients with primary refractory acute myeloid leukemia: a historical prospective analysis of the German and Israeli experience

Primary refractory acute myeloid leukemia (AML) is associated with a dismal prognosis. The FLAMSA-reduced intensity conditioning protocol (total body irradiation or treosulfan-based) has been described as an effective approach in patients with refractory leukemia undergoing allogeneic hematopoietic cell transplantation. A modified protocol (without amsacrine) has also recently been used. We retrospectively analyzed the transplantation characteristics and outcomes of all consecutive patients between the years 2003 and 2017 (n=51) diagnosed with primary refractory AML who underwent transplantation at the University of Cologne and the Tel Aviv Medical Center. Median age was 54 years and median follow up was 37 months. Median time to neutrophil and platelet engraftment was 13 (range, 8-19) and 13 (range, 7-30) days, respectively. None of the patients had primary graft failure. Incidences of grade 2-4 and grade 3-4 acute graft-versus-host disease (GvHD), overall and moderate-severe chronic GvHD were 50% (95%CI: 41-67%), 12% (95%CI: 3-25%), 61% (95%CI: 47-72%), and 42% (95%CI: 34-51%), respectively. Anti-thymocyte globulin administration was associated with lower incidence of acute GvHD (HR: 0.327; P=0.02). Non-relapse mortality at three months and three years were 6% and 16%, respectively. Relapse incidences were 6% and 29%, respectively. Overall survival rates at three months, three and five years were 90%, 61%, and 53%, respectively. Chronic GvHD disease was associated with a decreased mortality rate (HR: 0.397; P=0.045). We conclude that sequential therapy in patients with primary refractory acute myeloid leukemia is safe and provides a remarkable anti-leukemic effect with durable survival and should be considered for every patient with primary refractory disease.

Automated Manufacturing of Potent CD20-Directed Chimeric Antigen Receptor T Cells for Clinical Use

The clinical success of gene-engineered T cells expressing a chimeric antigen receptor (CAR), as manifested in several clinical trials for the treatment of B cell malignancies, warrants the development of a simple and robust manufacturing procedure capable of reducing to a minimum the challenges associated with its complexity. Conventional protocols comprise many open handling steps, are labor intensive, and are difficult to upscale for large numbers of patients. Furthermore, extensive training of personnel is required to avoid operator variations. An automated current Good Manufacturing Practice-compliant process has therefore been developed for the generation of gene-engineered T cells. Upon installation of the closed, single-use tubing set on the CliniMACS Prodigy™, sterile welding of the starting cell product, and sterile connection of the required reagents, T cells are magnetically enriched, stimulated, transduced using lentiviral vectors, expanded, and formulated. Starting from healthy donor (HD) or lymphoma or melanoma patient material (PM), the robustness and reproducibility of the manufacturing of anti-CD20 specific CAR T cells were verified. Independent of the starting material, operator, or device, the process consistently yielded a therapeutic dose of highly viable CAR T cells. Interestingly, the formulated product obtained with PM was comparable to that of HD with respect to cell composition, phenotype, and function, even though the starting material differed significantly. Potent antitumor reactivity of the produced anti-CD20 CAR T cells was shown in vitro as well as in vivo. In summary, the automated T cell transduction process meets the requirements for clinical manufacturing that the authors intend to use in two separate clinical trials for the treatment of melanoma and B cell lymphoma.

Sorafenib promotes graft-versus-leukemia activity in mice and humans through IL-15 production in FLT3-ITD-mutant leukemia cells

Individuals with acute myeloid leukemia (AML) harboring an internal tandem duplication (ITD) in the gene encoding Fms-related tyrosine kinase 3 (FLT3) who relapse after allogeneic hematopoietic cell transplantation (allo-HCT) have a 1-year survival rate below 20%. We observed that sorafenib, a multitargeted tyrosine kinase inhibitor, increased IL-15 production by FLT3-ITD+ leukemia cells. This synergized with the allogeneic CD8+ T cell response, leading to long-term survival in six mouse models of FLT3-ITD+ AML. Sorafenib-related IL-15 production caused an increase in CD8+CD107a+IFN-γ+ T cells with features of longevity (high levels of Bcl-2 and reduced PD-1 levels), which eradicated leukemia in secondary recipients. Mechanistically, sorafenib reduced expression of the transcription factor ATF4, thereby blocking negative regulation of interferon regulatory factor 7 (IRF7) activation, which enhanced IL-15 transcription. Both IRF7 knockdown and ATF4 overexpression in leukemia cells antagonized sorafenib-induced IL-15 production in vitro. Human FLT3-ITD+ AML cells obtained from sorafenib responders following sorafenib therapy showed increased levels of IL-15, phosphorylated IRF7, and a transcriptionally active IRF7 chromatin state. The mitochondrial spare respiratory capacity and glycolytic capacity of CD8+ T cells increased upon sorafenib treatment in sorafenib responders but not in nonresponders. Our findings indicate that the synergism of T cells and sorafenib is mediated via reduced ATF4 expression, causing activation of the IRF7-IL-15 axis in leukemia cells and thereby leading to metabolic reprogramming of leukemia-reactive T cells in humans. Therefore, sorafenib treatment has the potential to contribute to an immune-mediated cure of FLT3-ITD-mutant AML relapse, an otherwise fatal complication after allo-HCT.

Impact of choice, timing, sequence and combination of broad-spectrum antibiotics on the outcome of allogeneic haematopoietic stem cell transplantation

Recent data link the incidence of intestinal GvHD (iGvHD) after allogeneic haematopoietic stem cell transplantation (aSCT) to exposure with piperacillin-tazobactam or imipenem-cilastatin. To assess relevance of timing, duration, sequence and combination of antibiotic treatment in this setting, we applied a time-dependent model to our aSCT cohort. Patients from the prospective Cologne Cohort of Neutropenic Patients (CoCoNut) undergoing aSCT from January 2007 to April 2013 were included into a time-dependent multivariate Cox proportional hazards regression model with backward-stepwise selection. In 399 eligible patients, cumulative antibiotic exposure (hazard ratio (HR) 2.46; 95% confidence interval (95% CI) 1.59-3.81; P<0.001) and exposure to sequential treatment with penicillin derivatives and carbapenems (HR 6.22, 95% CI 1.27-30.31), but not to the individual classes, were associated with iGvHD at day 100. Glycopeptides were assessed as a risk factor (HR 3.73, 95% CI 1.51-9.19), but not considered independent, since their use was dependent on previous exposure to penicillin derivatives and carbapenems. Patients with iGvHD presented with increased non-relapse mortality at day 365 (HR 3.51; 95% CI 2.10-5.89; P<0.001). We identified sequential exposure to penicillin derivatives and carbapenems as well as overall exposure to antibiotics as independent risk factors for iGVHD. Confirmation of these findings in larger, prospective cohorts is necessary.

Dynamics of Torque Teno virus viremia could predict risk of complications after allogeneic hematopoietic stem cell transplantation

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is an established treatment option for several hematological diseases. However, the first year post-transplantation is often complicated by infections and graft-versus-host disease (GVHD). Improvements in immunological monitoring could reduce such post-transplant complications. Torque Teno virus (TTV), a chronically persisting DNA virus, is reported to be a marker for immune function in immunocompromised patients. In the present study, the TTV kinetics were analyzed to investigate the potential role of TTV viremia as immune-competence read-out after allo-HSCT. Twenty-three monocentric allo-HSCT recipients were retrospectively tested for TTV-DNA in whole blood at given day post-transplant. Dynamics of TTV viremia was analyzed with respect to episodes of non-TTV viral reactivations (CMV, EBV, and BKPyV), acute GVHD, and recovery of immune cells. Recipients affected by persisting viral infections and/or GVHD during the first 100 days after allo-HSCT showed a significantly higher median TTV load at day +30 than patients with a less complicated clinical course (p = 0.005). This was also associated with a total lymphocyte count <5.5E+08 cells/L in this high-risk group (p = 0.039). These findings suggest that TTV could represent an additional parameter to identify patients at higher risk for complications in the first 100 days following allo-HSCT. Prospective studies, including the monitoring of lymphocyte subsets, are required to define the potential use of TTV in immunological monitoring after allo-HSCT.

Regulatory B10 cells display an altered homoeostasis in acute graft-versus-host disease

OBJECTIVE

The role of B cells and the subgroup of IL-10 producing B cells, known to have a regulatory function, in patients following a haematopoietic stem cell transplant (alloSCT) has not been clearly understood to date.

METHODS

We prospectively recruited 95 patients following an alloSCT and studied the B-cell reconstitution on days 30, 90 and 150. Regulatory B10 cells could be analysed in 22 consecutively recruited patients on day 30 post-transplant.

RESULTS

The total B-cell percentages in transplant recipients (median 0.33; range 0.01-5.9) were significantly reduced than the controls (P = 0.0001) and constituted predominantly of transitional CD24^high CD38^high B cells. Regulatory B10 cells could be analysed in 22 consecutively recruited patients on day 30 post-transplant. The percentages of B10 cells (median 1.35; 0.0-4.5) were significantly reduced in the transplant recipients in comparison with the control cohort (P < 0.0001). Interestingly, the percentages of B10 cells in patients with acute GvHD (median 1.7; 0.33-4.5) were significantly higher than those without GvHD (median 0.7; 0-1.9) (P = 0.0003).

CONCLUSION

This is the first report demonstrating B10 cells in stem cell transplant recipients in the early post-alloSCT (30 d) period. Our data suggest a possible role for B10 cells in the pathophysiology of acute GvHD. Further longitudinal studies are warranted to understand the implications of our findings.

Treatment of severe chronic ocular graft-versus-host disease using 100% autologous serum eye drops from a sealed manufacturing system: a retrospective cohort study

BACKGROUND/AIMS

To analyse patients with chronic ocular graft-versus-host disease (GvHD) under treatment with 100% autologous serum eye drops from a sealed manufacturing system.

METHODS

17 patients with chronic ocular GvHD received 100% autologous serum eye drops from single use vials manufactured in a sealed system. Retrospective analysis included visual acuity, corneal staining, frequency of artificial tears, ocular symptoms by means of a questionnaire and information on subjective side effects and cost compensation.

RESULTS

Data of prior to autologous serum eye drops therapy and at a 6-month follow-up were obtained. They demonstrated a significant increase in visual acuity (logMAR oculus dexter/right eye (OD) 0.5±0.32 to 0.4±0.3; oculus sinister/left eye (OS) 0.6±0.35 to 0.3±0.35; p=0.177/0.003) and significant improvement in corneal staining (Oxford grading scheme: OD from 3±1.03 to 2±1.43, OS from 4±1.0 to 2±1.09, p=0.004/0.001) and ocular symptoms (ocular surface disease index: 88±20.59 to 63±22.77; p=0.02). Frequency of artificial tears was reduced and no side effects were reported. Patient satisfaction was 100%, and cost compensation by health insurance reached 80%.

CONCLUSIONS

100% autologous serum eye drops using a sealed manufacturing system were efficient in improving the ocular surface, patient symptoms and visual acuity without side effects. It seems to be safe to use 100% autologous serum despite earlier suspicions regarding immune complex accumulations and exacerbation of ocular surface inflammation. The potential effects of serum levels of systemic immunosuppressives through readministration onto the ocular surface need to be elucidated.

Immunological effects in patients with steroid-refractory graft-versus-host disease following treatment with basiliximab, a CD25 monoclonal antibody

Steroid-refractory graft-versus-host disease (GvHD) is a complication following an allogeneic stem cell transplantation with limited therapeutic options. Studies have shown a response in up to 80% of patients with this condition after treatment with the CD25 monoclonal antibody, basiliximab. Despite the good responses to treatment, around 50% of the patients experience recurrence of their GvHD symptoms 4-6 wk following cessation of therapy. The in vivo changes in the following treatment with this antibody have not been elucidated so far. We treated 14 patients with severe steroid-refractory GvHD with basiliximab weekly for 4 wk and monitored the changes in the T-, B-, NK- and dendritic cell subsets over this time period. The overall response to treatment was 92% (13/14) with 50% (7/14) achieving a complete response. Fifty four percentage (7/13) of the patients who responded showed recurrence of their GvHD symptoms. Contrary to expectations, our observations showed a significant depletion of the regulatory T-cell subset following treatment. Our findings suggest that the undesirable depletion of the regulatory T cells along with the CD25(+) acute inflammatory cells might be responsible for the high incidence of GvHD recurrence in this cohort of patients.

Nonmyeloablative allogeneic stem cell transplantation for chronic lymphocytic leukaemia offers the possibility of disease control with minimal morbidity and mortality--a single institution experience

Allogeneic stem cell transplantation is a treatment option for patients with poor risk CLL. We conducted a retrospective analysis of all CLL patients allografted at our institution, the University Hospital of Cologne, Germany. Data was collected on 40 patients from 2004 to 2012. The mean age was 54, and the majority were male (75 %). On average, the patients were diagnosed 6 years (range 2-12) prior to transplant with an average of 4 years (range 1-8) from time of first-line therapy to transplant. The remission states at the time of transplant were complete remission (CR) (n = 4), stable disease (n = 10), partial remission (n = 20) and progressive disease (n = 6). Only reduced intensity conditioning regimens were employed. The average CD34(+) cell dose was 4.16 × 10(6)/kg. Neutrophil engraftment was seen by day +17 (range 10-23) post-transplant, and 88 % achieved 95-100 % donor chimerism by day 100. Overall survival, progression-free survival and non-relapse mortality at 2 years post-transplant were 65, 52.5 and 27.5 %, respectively. A total of 51 % of patients were found to be minimal residual disease (MRD)-negative at 1 year post-transplant. Our single-centre experience confirms the valuable role of allogeneic stem cell transplantation (allo-SCT) in the treatment of poor risk CLL patients with promising long-term survival and acceptable transplant-related mortality. The advent of newer therapeutic agents should not hinder the consideration of allo-SCT for this patient cohort as it remains the only curative option for these patients.

Ruxolitinib in corticosteroid-refractory graft-versus-host disease after allogeneic stem cell transplantation: a multicenter survey

Despite major improvements in allogeneic hematopoietic cell transplantation over the past decades, corticosteroid-refractory (SR) acute (a) and chronic (c) graft-versus-host disease (GVHD) cause high mortality. Preclinical evidence indicates the potent anti-inflammatory properties of the JAK1/2 inhibitor ruxolitinib. In this retrospective survey, 19 stem cell transplant centers in Europe and the United States reported outcome data from 95 patients who had received ruxolitinib as salvage therapy for SR-GVHD. Patients were classified as having SR-aGVHD (n=54, all grades III or IV) or SR-cGVHD (n=41, all moderate or severe). The median number of previous GVHD-therapies was 3 for both SR-aGVHD (1-7) and SR-cGVHD (1-10). The overall response rate was 81.5% (44/54) in SR-aGVHD including 25 complete responses (46.3%), while for SR-cGVHD the ORR was 85.4% (35/41). Of those patients responding to ruxolitinib, the rate of GVHD-relapse was 6.8% (3/44) and 5.7% (2/35) for SR-aGVHD and SR-cGVHD, respectively. The 6-month-survival was 79% (67.3-90.7%, 95% confidence interval (CI)) and 97.4% (92.3-100%, 95% CI) for SR-aGVHD and SR-cGVHD, respectively. Cytopenia and cytomegalovirus-reactivation were observed during ruxolitinib treatment in both SR-aGVHD (30/54, 55.6% and 18/54, 33.3%) and SR-cGVHD (7/41, 17.1% and 6/41, 14.6%) patients. Ruxolitinib may constitute a promising new treatment option for SR-aGVHD and SR-cGVHD that should be validated in a prospective trial.