Digital PCR Improves Sensitivity and Quantification in Monitoring CAR-T Cells in B Cell Lymphoma Patients.

Chimeric antigen receptor T cells (CAR-T) has emerged as a promising therapy, over 60% of patients fail to sustain a long-term response. The underlying factors that leads to the effectiveness of this therapy are not completely understood, CAR-T cell persistence and monitoring seems to be pivotal for ensuring a successful response. Various monitoring methods such as multiparametric flow cytometry (MFC) or quantitative PCR (qPCR) have been applied. Our objective is to develop digital PCR (dPCR) assays for detection and quantification of CAR-T cells, comparing them with MFC and qPCR. Samples taken at different follow-up times from 45 patients treated with CAR-T therapy were analyzed to assess the correlation between the different methodologies. dPCR presented a high correlation with MFC and qPCR (r = 0.97 and r = 0.87, respectively), while offering a higher sensitivity (0.01%) compared to MFC (0.1%) and qPCR (1%). dPCR emerged as an alternative and highly sensitivity method for monitoring CAR-T cell dynamics. This technique is well-suited for implementation in clinical practice as a complementary technique to MFC.

Impact of SCHOLAR-1 Criteria on Chimeric Antigen Receptor T Cell Therapy Efficacy in Aggressive B Lymphoma: A Real-World GELTAMO/GETH Study.

In the pre-chimeric antigen receptor T cell (CAR-T) therapy era, the SCHOLAR-1 study identified a group of patients with refractory aggressive B cell lymphoma (ABCL) with particularly poor prognoses. We recently published our real-world data from Spain, focused on this SCHOLAR-1 refractory group, and compared patients who underwent CAR-T therapy with the previous standard of care. In this study, we found that the efficacy of CAR-T therapy in refractory patients, in terms of progression-free survival (PFS) and overall survival (OS), was superior to that of the treatments available in the pre-CAR-T era. The main objective of these new analyses was to analyze treatment efficacy in terms of response rates and survival for patients with ABCL with or without the SCHOLAR-1 criteria. In addition, we analyzed the prognostic impact of each SCHOLAR-1 criterion independently. Our study aimed to assess the prognostic impact of SCHOLAR-1 criteria on ABCL patients treated with CAR-T therapy in Spain. This multicenter, retrospective, observational study. We included all adult patients treated with commercially available CAR-T cell products and diagnosed with ABCL different from primary mediastinal large B cell lymphoma between February 2019 and July 2022. Patients meeting any SCHOLAR-1 criteria (progressive disease as the best response to any line of therapy, stable disease as the best response to ≥4 cycles of first-line therapy or ≥2 cycles of later-line therapy, or relapse at <12 months after autologous stem cell transplantation [auto-SCT]) in the line of treatment before CAR-T therapy (SCHOLAR-1 group) were compared with those not meeting any of these criteria (non-SCHOLAR-1 group). To analyze the prognostic impact of individual SCHOLAR-1 criteria, all the patients who met any of the SCHOLAR-1 criteria at any time were included to assess whether these criteria have the same prognostic impact in the CAR-T era. In addition, patients were grouped according to whether they were refractory to the first line of treatment, refractory to the last line of treatment, or relapsed early after auto-SCT. The PFS and OS were calculated from the time of appearance of the SCHOLAR-1 refractoriness criteria. Of 329 patients treated with CAR-T (169 with axi-cel and 160 with tisa-cel), 52 were in the non-SCHOLAR-1 group and 277 were in the SCHOLAR-1 group. We found significantly better outcomes in the non-SCHOLAR-1 patients compared with the SCHOLAR-1 patients (median PFS of 12.2 and 3.3 months, respectively; P = .009). In addition, axi-cel showed better results in terms of efficacy than tisa-cel for both the non-SCHOLAR-1 group (hazard ratio [HR] for PFS, 2.7 [95% confidence interval (CI), 1.1 to 6.7; P = .028]; HR for OS, 7.1 [95% CI, 1.5 to 34.6; P = .015]) and SCHOLAR-1 group (HR for PFS, 1.8 [95% CI, 1.3 to 2.5; P < .001]; HR for OS, 1.8 [95% CI, 1.2 to 2.6; P = .002]), but also significantly more toxicity. Finally, separately analyzing the prognostic impact of each SCHOLAR-1 criterion revealed that refractoriness to the last line of treatment was the variable with the most significant impact on survival. In conclusion, SCHOLAR-1 refractoriness criteria notably influence the efficacy of CAR-T therapy. In our experience, axi-cel showed better efficacy than tisa-cel for both SCHOLAR-1 and non-SCHOLAR-1 patients. Refractoriness to the last line of treatment was the variable with the most significant impact on survival in the CAR-T therapy era.

Expert Consensus: Main Risk Factors for Poor Prognosis in COVID-19 and the Implications for Targeted Measures against SARS-CoV-2.

The clinical evolution of patients infected with the Severe Acute Respiratory Coronavirus type 2 (SARS-CoV-2) depends on the complex interplay between viral and host factors. The evolution to less aggressive but better-transmitted viral variants, and the presence of immune memory responses in a growing number of vaccinated and/or virus-exposed individuals, has caused the pandemic to slowly wane in virulence. However, there are still patients with risk factors or comorbidities that put them at risk of poor outcomes in the event of having the coronavirus infectious disease 2019 (COVID-19). Among the different treatment options for patients with COVID-19, virus-targeted measures include antiviral drugs or monoclonal antibodies that may be provided in the early days of infection. The present expert consensus is based on a review of all the literature published between 1 July 2021 and 15 February 2022 that was carried out to establish the characteristics of patients, in terms of presence of risk factors or comorbidities, that may make them candidates for receiving any of the virus-targeted measures available in order to prevent a fatal outcome, such as severe disease or death. A total of 119 studies were included from the review of the literature and 159 were from the additional independent review carried out by the panelists a posteriori. Conditions found related to strong recommendation of the use of virus-targeted measures in the first days of COVID-19 were age above 80 years, or above 65 years with another risk factor; antineoplastic chemotherapy or active malignancy; HIV infection with CD4+ cell counts < 200/mm3; and treatment with anti-CD20 immunosuppressive drugs. There is also a strong recommendation against using the studied interventions in HIV-infected patients with a CD4+ nadir <200/mm3 or treatment with other immunosuppressants. Indications of therapies against SARS-CoV-2, regardless of vaccination status or history of infection, may still exist for some populations, even after COVID-19 has been declared to no longer be a global health emergency by the WHO.

Poor graft function after haploidentical stem cell transplantation with post-transplant cyclophosphamide.

This is a retrospective cohort study of consecutive adult patients who received a haploidentical-SCT (haplo-SCT) with post-transplant cyclophosphamide (PT-Cy) in a single centre. Poor graft function (PGF) was defined as the occurrence of either persistent neutropenia (ANC < 0.5 × 109/µL) with poor response to granulocyte colony-stimulating factors (G-CSF) and/or thrombocytopenia (platelets < 20 × 109/L) with transfusion dependence, with complete donor chimerism and without concurrent severe GVHD or underlying disease relapse, during the first 12 months after transplantation. Forty-four (27.5%) out of 161 patients were diagnosed with PGF. Previous CMV reactivation was significantly more frequent in patients with PGF (88.6% versus 73.5%, p = 0.04) and the number of reactivations was also higher in these patients. Besides, early CMV reactivations in the first 6 months post-SCT were also significantly more frequent among patients with PGF (88.6% versus 71.8% p = 0.025). Thirty-two percent of patients with PGF were treated with increasing doses of thrombopoietin-receptor agonists (TRA) and 7 patients were treated with a donor CD34 + selected boost. In total, 93.2% of patients reached adequate peripheral blood counts in a median time of 101 days (range 11-475) after diagnosis. PGF is a frequent complication after haplo-SCT with PT-Cy. CMV reactivation might be the most relevant factor associated to its development. Even when most patients recover peripheral counts with support therapy, there is a group of patients with persistent cytopenias who can effectively be treated with TRA and/or a boost of CD34 + selective cells.

Novel Candidate loci and Pathogenic Germline Variants Involved in Familial Hematological Malignancies Revealed by Whole-Exome Sequencing.

The familial occurrence of hematological malignancies has been underappreciated. Recent studies suggest that up to 15% of adults with myeloid neoplasms carry germline pathogenic variants in cancer-predisposing genes. This study aimed to identify the underlying germline predisposition variant in patients with a strong family or personal onco-hematological history using whole exome sequencing on sixteen uncharacterized individuals. It was carried out in two groups of patients, one with samples available from two affected relatives (Cohort A) and one with available samples from the index case (Cohort B). In Cohort A, six families were characterized. Two families shared variants in genes associated with DNA damage response and involved in cancer development (CHEK2 and RAD54L). Pathogenic or likely pathogenic germline variants were also found in novel candidate genes (NFATC2 and TC2N). In two families, any relevant pathogenic or likely pathogenic genomic variants were identified. In Cohort B, four additional index cases were analyzed. Three of them harbor clinically relevant variants in genes with a probable role in the development of inherited forms of hematological malignancies (GATA1, MSH4 and PRF1). Overall, whole exome sequencing is a useful approach to achieve a further characterization of these patients and their mutational spectra. Moreover, further investigations may help improve optimization for disease management of affected patients and their families.

Association between gene polymorphisms in the cyclophosphamide metabolism pathway with complications after haploidentical hematopoietic stem cell transplantation.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative treatment for patients with hematologic malignances. Haploidentical HSCT (Haplo-HSCT) is an alternative option for patients who do not have an HLA-matched donor. The use of post-transplantation high dose cyclophosphamide (PT-Cy) is commonly employed for graft-versus-host disease (GVHD) prophylaxis in haplo-HSCT. Cyclophosphamide (Cy) is an alkylating agent with antineoplastic and immunosuppressive activity, whose bioactivation requires the activity of polymorphic enzymes in the liver to produce phosphoramide mustard, which is a DNA alkylating agent. To identify polymorphisms in the genes of Cy metabolism and correlate them with post-HSCT complications [GVHD, sinusoidal obstruction syndrome (SOS), hemorrhagic cystitis (HC) and transplant-related mortality (TRM)], we designed a custom next-generation sequencing panel with Cy metabolism enzymes. We analyzed 182 patients treated with haplo-HSCT with PT-Cy from 2007 to 2019, detecting 40 variants in 11 Cy metabolism genes. Polymorphisms in CYP2B6, a major enzyme involved in Cy activation, were associated with decreased activity of this enzyme and a higher risk of Graf-versus-host disease (GVHD). Variants in other activation enzymes (CYP2A6, CYP2C8, CYP2C9, CYP2C19) lead to decreased enzyme activity and were associated with GVHD. Polymorphisms in detoxification genes such as glutathione S-transferases decreased the ability to detoxify cyclophosphamide metabolites due to lower enzyme activity, which leads to increased amounts of toxic metabolites and the development of III-IV acute GVHD. GSMT1*0 a single nucleotide polymorphism previously recognized as a risk factor for SOS was associated with a higher risk of SOS. We conclude that polymorphisms of genes involved in the metabolism of cyclophosphamide in our series are associated with severe grades of GVHD and toxicities (SOS and TRM) after haplo-HSCT and could be used to improve the clinical management of transplanted patients.

FLT3-ITD Expression as a Potential Biomarker for the Assessment of Treatment Response in Patients with Acute Myeloid Leukemia.

FLT3-internal tandem duplication (ITD) analysis is not typically performed in cDNA samples and is not considered an appropriate marker for monitoring measurable residual disease (MRD). The aims of this study were to compare FLT3-ITD mutation analysis in DNA and cDNA samples at diagnosis and to demonstrate the usefulness of its expression measurement as an MRD marker after allogeneic stem cell transplantation (allo-HSCT) or FLT3 inhibitor (FLT3i) administration. A total of 46 DNA and cDNA diagnosis samples, 102 DNA and cDNA post-allo-HSCT samples from 34 patients and 37 cDNA samples from 7 patients with refractory/relapse AML treated with FLT3i were assessed for the FLT3-ITD mutation through fragment analysis. In terms of sensitivity, the analysis of cDNA was superior to that of DNA, quantifying higher allelic ratio values in most cases at diagnosis, and thus optimizing the detection of minor clones and prognostic classification. Regarding the last sample before post-HSCT relapse, cDNA analysis anticipated relapse in most cases, unlike DNA analyses. With regard to the post-FLT3i follow-up, FLT3-ITD expression was reduced after the first FLT3i cycle when the treatment was effective, whereas it was not reduced in refractory patients. FLT3-ITD expression could be a useful additional biomarker at diagnosis and for the assessment of MRD after allo-HSCT and FLT3i in AML.

Allogeneic CD34-selected stem cell boost as salvage treatment of life-threatening infection and severe cytopenias after CAR-T cell therapy.

BACKGROUND: A variable incidence of profound cytopenia has been described in patients receiving chimeric antigen receptor T-cell (CAR-T) therapy for relapsed or refractory (R/R) B-cell acute lymphoblastic leukemia (ALL). This complication leads to severe infection in some cases, especially those who present additional risk factors including prior hematopoietic stem cell transplantation (HSCT). STUDY DESIGN AND METHODS: We report a case of breakthrough invasive fungal infection in a patient with prolonged neutropenia after CAR-T cell therapy administered for relapsed B-cell ALL after allogeneic haploidentical HSCT. RESULTS: After disease progression was discarded, therapy with antifungal agents, G-CSF and thrombopoietin analogue was started. However, no sign of haematological recovery or infection improvement was observed. A fresh mobilized selected CD34-stem cell boost from her haploidentical transplant donor was infused without further conditioning. Within 15 days of mobilized CD34-boost administration the patient showed complete resolution of both the aplasia and fungal infection. DISCUSSION: This case illustrates as proof-of-concept the efficacy and safety of selected CD34-stem cell boost from prior donor as salvage treatment of prolonged cytopenias after CAR-T cell therapy.

Immune Checkpoint Inhibitors in Acute Myeloid Leukemia: A Meta-Analysis.

Background: Experience with immune checkpoint inhibitors (ICIs) in the treatment of acute myeloid leukemia (AML) is still limited and based on early clinical trials, with no reported randomized clinical data. In this study, we reviewed the available evidence on the use of ICIs, either in monotherapy or in combination with other treatments, in different AML settings, including newly diagnosed AML, relapsed or refractory (R/R) AML and maintenance treatment after allogeneic-HSCT (allo-HSCT). Materials and Methods: A systematic literature review was conducted using PubMed electronic database as primary source to identify the studies involving immune checkpoint inhibitors in first-line and R/R AML. We recorded Overall Response (ORR), Complete Response (CR) and Complete Response with incomplete count recovery (CRi) rates, overall survival (OS) and immune-related adverse events ≥ grade 3 (irAEs). Hereafter, we analyzed the overall profile of these ICIs by performing a meta-analysis of the reported outcomes. Results: A total of 13 studies were identified where ICI was used in patients with AML. ORR across these studies was 42% (IC95%, 31% - 54%) and CR/CRi was 33% (IC95%, 22%-45%). Efficacy was also assessed considering the AML setting (first-line vs. relapsed/refractory) and results pointed to higher response rates in first-line, compared to R/R. Mean overall survival was 8.9 months [median 8 months, (IC95%, 3.9 - 15.5)]. Differences between first line and R/R settings were observed, since average overall survival in first line was 12.0 months, duplicating the OS in R/R which was 7.3 months. Additionally, the most specific adverse events (AEs) of these therapies are immune-related adverse events (irAEs), derived from their inflammatory effects. Grade ≥3 irAEs rate was low and similar among studies [12% (95%CI 8% - 16%)]. Conclusion: ICIs in combination with intensive chemotherapy, hypomethylating agents or other targeted therapies are gaining interest in the management of hematological malignancies such as AML. However, results obtained from clinical trials are modest and limited by both, the type of design and the clinical trial phase. Hopefully, the prospective study of these therapies in late-stage development could help to identify patients who may benefit from ICI therapy.

Mobile Apps for Hematological Conditions: Review and Content Analysis Using the Mobile App Rating Scale.

BACKGROUND: Hematological conditions are prevalent disorders that are associated with significant comorbidities and have a major impact on patient care. Concerning new tools for the care of these patients, the number of health apps aimed at hematological patients is growing. Currently, there are no quality analyses or classifications of apps for patients diagnosed with hematological conditions. OBJECTIVE: The aim of this study is to analyze the characteristics and quality of apps designed for patients diagnosed with hematological conditions by using the Mobile App Rating Scale (MARS). METHODS: We performed an observational, cross-sectional descriptive study of all smartphone apps for patients diagnosed with hematological conditions. A search was conducted in March 2021 using the following terms: anemia, blood cancer, blood disorder, hematological cancer, hematological malignancy, hematological tumor, hematology, hemophilia, hemorrhage, lymphoma, leukemia, multiple myeloma, thalassemia, thrombocytopenia, and thrombosis. The apps identified were downloaded and evaluated by 2 independent researchers. General characteristics were registered, and quality was analyzed using MARS scores. Interrater reliability was measured by using the Cohen κ coefficient. RESULTS: We identified 2100 apps in the initial search, and 4.19% (88/2100) of apps met the inclusion criteria and were analyzed. Of the 88 apps, 61% (54/88) were available on Android, 30% (26/88) were available on iOS, and 9% (8/88) were available on both platforms. Moreover, 7% (6/88) required payment, and 49% (43/88) were updated in the last year. Only 26% (23/88) of the apps were developed with the participation of health professionals. Most apps were informative (60/88, 68%), followed by preventive (23/88, 26%) and diagnostic (5/88, 6%). Most of the apps were intended for patients with anemia (23/88, 26%). The mean MARS score for the overall quality of the 88 apps was 3.03 (SD 1.14), ranging from 1.19 (lowest-rated app) to 4.86 (highest-rated app). Only 47% (41/88) of the apps obtained a MARS score of over 3 points (acceptable quality). Functionality was the best-rated section, followed by aesthetics, engagement, information, and app subjective quality. The five apps with the highest MARS score were the following: Multiple Myeloma Manager, Hodgkin Lymphoma Manager, Focus On Lymphoma, ALL Manager, and CLL Manager. The analysis by operating system, developer, and cost revealed statistically significant differences in MARS scores (P<.001, P<.001, and P=.049, respectively). The interrater agreement between the 2 reviewers was substantial (k=0.78). CONCLUSIONS: There is great heterogeneity in the quality of apps for patients with hematological conditions. More than half of the apps do not meet acceptable criteria for quality and content. Most of them only provide information about the pathology, lacking interactivity and personalization options. The participation of health professionals in the development of these apps is low, although it is narrowly related to better quality.

Hemophagocytic lymphohistiocytosis/macrophage activation syndrome (HLH/MAS) following treatment with tisagenlecleucel.

Chimeric antigen receptor (CAR) T cell-related HLH/MAS is an unusual manifestation of severe cytokine release syndrome (CRS) with poor prognosis and a challenging diagnosis. The establishment of specific diagnosis criteria is essential, and the combination of several techniques for CAR T-cell follow-up, allows a more precise management of this complication.

Implementation of a hospital-at-home (HAH) unit for hematological patients during the COVID-19 pandemic: safety and feasibility.

BACKGROUND: "Hospital-at-home" (HAH) programs have been shown to optimize resource utilization, shorten hospitalization and prevent nosocomial infection. METHODS: We retrospectively analysed data regarding implementation of an HAH unit for caring patients with hematological malignancies in our center, during the COVID-19 pandemic. RESULTS: Between January and November 2020, 105 patients were treated in the HAH unit for a total of 204 episodes. Nine patients with multiple myeloma (MM) received autologous HSCT (auto-HSCT). Three patients with acute myeloid leukemia (AML) received consolidation therapy, 32 patients underwent clinical and analytical monitoring, 20 were transplant recipients early discharged (5 auto-HSCT and 15 allo-HSCT) and 2 had received CART cells therapy. Azacitidine, bortezomib and carfilzomib were administered at home to 54 patients with AML, myelodysplastic syndrome (MDS) or MM. A median of 17 (IQR 13-19) days of admission per patient and a total of 239 visits to the Hematology day-care hospital were avoided. Overall, 28 patients (14% of all episodes) needed admission to the hospital, 4 of them due to COVID-19. CONCLUSIONS: Implementation of a Hematology HAH unit was feasible and safe, and provided thorough advanced care to a high-risk population. Advanced care-at-home strategies can be crucial during times of COVID-19 to minimize treatment interruptions and reduce the risk of cross-infections.

Frequency, Clinical Characteristics and Outcome of Adults With Acute Lymphoblastic Leukemia and COVID 19 Infection in the First vs. Second Pandemic Wave in Spain.

BACKGROUND AND OBJECTIVE: SARS-CoV-2 infection has bimodal distribution in Europe with a first wave in March to June 2020 and a second in September 2020 to February 2021. We compared the frequency, clinical characteristics and outcomes of adults with acute lymphoblastic leukemia (ALL) and infection in the first vs. second pandemic waves in Spain. PATIENTS AND METHODS: In this prospective study the characteristics of ALL and COVID-19 infection, comorbidities, treatment and outcome in the two periods were compared. The study ended when vaccination against SARS-CoV-2 was implemented in Spain. RESULTS: Twenty eight patients were collected in the first wave and 24 in the second. The median age was 46.5 years (range 20-83). Patients from the first wave had a trend to more severe ALL (higher frequency of patients under induction or submitted to transplantation or under immunosuppressive therapy). No significant differences were observed in need for oxygen support, intensive care unit (ICU) requirement, days in ICU and time to COVID-19 infection recovery. Seventeen patients (33%) died, with death attributed to COVID infection in 15 (29%), without significant differences in the 100 day overall survival (OS) probabilities in the two waves (68% ± 17% vs. 56% ± 30%). The only prognostic factor for OS identified by was the presence of comorbidities at COVID-19 infection (HR: 5.358 [95% CI: 1.875- 15.313]). CONCLUSION: The frequency and mortality of COVID-19 infection were high in adults with ALL, without changes over time, providing evidence in favor of vaccination priority for these patients.

Outcomes and prognostic factors of adults with refractory or relapsed T-cell acute lymphoblastic leukemia included in measurable residual disease-oriented trials.

Despite high complete remission (CR) rates with frontline therapy, relapses are frequent in adults with T-cell acute lymphoblastic leukemia (T-ALL) with limited salvage options. We analyzed the outcomes and prognostic factors for CR to salvage therapy and overall survival (OS) of patients with R/R T-ALL included in two prospective measurable residual disease-oriented trials. Seventy-five patients (70 relapsed, 5 refractory) were identified. Relapses occurred in bone marrow, isolated or combined in 50 patients, and in the central nervous system (CNS; isolated or combined) in 20. Second CR was attained in 30/75 patients (40%). Treatment with FLAG-Ida and isolated CNS relapse were independently associated with a higher CR rate after first salvage therapy. The median OS was 6.2 (95% confidence interval [CI], 3.9-8.6) months, with a 4-year OS probability of 18% (95% CI, 9%-27%). No differences in survival were observed according to the treatment with hematopoietic stem cell transplantation in patients in CR after first salvage therapy. Multivariable analysis showed a ≥12-month interval between first CR and relapse, CR after first salvage therapy and isolated CNS relapse as favorable prognostic factors for OS with hazard ratios (HR) (95% CI) of 1.931 (1.109-3.362), 2.958 (1.640-5.334), and 2.976 (1.157-7.655), respectively. This study confirms the poor outcomes of adults with R/R T-ALL among whom FLAG-Ida was the best of the rescue therapies evaluated. Late relapse, CR after first rescue therapy and isolated CNS relapse showed prognostic impact on survival. More effective rescue therapies are needed in adults with R/R T-ALL.

Clinical Utility of the Detection of the Loss of the Mismatched HLA in Relapsed Hematological Patients After Haploidentical Stem Cell Transplantation With High-Dose Cyclophosphamide.

Haploidentical hematopoietic stem cell transplantation (Haplo-HSCT) with high-dose cyclophosphamide (PTCy) has resulted in a low incidence of graft-vs.-host disease (GVHD), graft failure, and non-relapse mortality. However, post-transplantation relapse remains a common cause of treatment failure in high-risk patients. Unraveling the mechanisms of relapse is therefore crucial for designing effective relapse treatment strategies. One of these mechanisms is the loss of the mismatched HLA on the recipient's leukemic cells. To study the incidence and clinical relevance of this phenomenon, we analyzed 181 patients treated with Haplo-HSCT with PTCy (2007-2019), of which 37 relapsed patients after transplantation. According to the kit employed for HLA-loss analysis, among 22 relapsed patients, we identified HLA loss at relapse in 6 of the 22 patients (27%) studied. Based on the results obtained, the genomic loss of HLA was more common in females than males (66 vs. 33%) and HLA-loss relapses occurred later than classical relapses (345 vs. 166 days). Moreover, the patients with HLA-loss had a greater presence of active disease at the time of transplantation and had undergone a larger number of treatment lines than the group with classical relapses (66 vs. 43% and 66 vs. 18%, respectively). Four of these relapses were studied retrospectively, while two were studied prospectively, the results of which could be considered for patient management. Additionally, two relapsed patients analyzed retrospectively had myeloid neoplasms. One patient had not undergone any treatment, and three had undergone donor lymphocyte infusions (DLIs) and chemotherapy. All presented severe GVHD and disease progression. In contrast, the two patients studied prospectively had a lymphoid neoplasm and were not treated with DLIs. One of them was treated with chemotherapy but died from disease progression, and the other patient underwent a second Haplo-HSCT from a different donor and is still alive. We can conclude that the detection of HLA-loss at the onset of relapse after Haplo-HSCT with PTCy could help in clinical practice to select appropriate rescue treatment, thereby avoiding the use of DLIs or a second transplantation from the same donor.

Defibrotide in hematopoietic stem cell transplantation: A multicenter survey study of the Spanish Hematopoietic Stem Cell Transplantation Group (GETH).

BACKGROUND: Defibrotide is approved in European Union for the treatment of severe sinusoidal obstruction syndrome (SOS) after HSCT. However, it has also been used for SOS prophylaxis, moderate SOS and in other complications such as transplant-associated thrombotic microangiopathy (TAM). The objective of this study was to evaluate current uses, effectiveness and safety of defibrotide in patients with HSCT. METHODS: This multicenter, retrospective study included patients treated with defibrotide for any indication at 28 HSCT centers of the Grupo Español de Trasplante Hematopoyetico (GETH) including the pediatric subgroup Grupo Español de Trasplante de Medula en Niños (GETMON). RESULTS: Three hundred and eighty eight patients treated with defibrotide between January 2011 and December 2018 were included. 253 patients were children, and 135 patients were adults. In total, 332 transplants were allogeneic, and the remainder were autologous. Main indications for defibrotide use were severe/very severe SOS in 173 patients, SOS prophylaxis in 135 patients, moderate SOS in 41 patients, TAM in six patients and suspected SOS in 33 patients. Overall survival (OS) at day +100 in the SOS prophylaxis group was 89% (95% CI, 87%-91%). In the group of patients with moderate and severe/very severe SOS, the OS at day +100 was 80% (95% CI, 74%-86%) and 62% (95% CI, 59%-65%), respectively (P = .0015). With a longer follow-up, median of 2 years (4 months-7 years), OS was 63% (95% CI, 59%-67%) in the SOS prophylaxis patients. OS for patients with moderate and severe/very severe SOS groups was 53% (95% CI, 47%-61%) and 26% (95% CI, 22%-30%), respectively (P = .006). 191 patients died, and SOS was the main cause of death in 23 patients (12%). CONCLUSIONS: Defibrotide has an acceptable safety profile with an improved response in severe/very severe SOS compared with historical controls, mainly in pediatric patients. Use of defibrotide for prophylaxis may improve prognosis of patients at high risk of complications due to endothelial damage such as those who receive a second transplant. SOS has an important impact on the HSCT long-term survival, as can be concluded from our study.

Tocilizumab as salvage treatment of refractory pulmonary acute graft-versus-host disease.

INTRODUCTION: Acute graft-versus-host disease GVHD (aGVHD) is the main complication during the first months after bone transplantation. Steroid therapy is clearly the upfront established treatment for aGVHD. However, there are patients with partial response to steroid treatment and steroid-refractory cases. For those patients, a vast number of therapeutic options have emerged, although the evidence is scarce. CASE REPORT: We report the use of tocilizumab as salvage treatment in a patient with corticosteroid refractory pulmonary aGVHD that was admitted to the critical care unit for respiratory support measures. MANAGEMENT & OUTCOME: We decided to use tocilizumab as rescue treatment, after failure of corticosteroid treatment, standard treatment with broad-spectrum antibiotics and etanercept. The patient showed a remarkable clinical improvement two days after first infusion and a total resolution of the symptomatology with normalization of the spirometry tests after 4 weeks of the administration of tocilizumab. DISCUSSION: To the authors' knowledge, this is the first case that describes the effective and safe use of tocilizumab as a rescue treatment in a patient with steroid-refractory pulmonary aGVHD. It showed a rapid onset of action and a favorable safety profile, which could make it an interesting option for the treatment of this potentially fatal complication.

Post-transplant cyclophosphamide for GVHD prophylaxis compared to ATG-based prophylaxis in unrelated donor transplantation.

Post-transplant cyclophosphamide (PTCY) effectively prevents graft-versus-host disease after unmanipulated HLA-haploidentical HSCT. The use of PTCY in the unrelated donor HSCT setting is less explored. We conducted a retrospective study of 132 consecutive patients undergoing a matched or 9/10 mismatched unrelated donor HSCT in 4 centers in Spain, 60 with anti-thymocyte globulin (ATG)-based prophylaxis combined with MTX-CsA, and 72 using a PTCY-based regimen. Peripheral blood stem cells were used as graft in most patients (111 patients, 84%); mMUD donors were balanced between groups. Cumulative incidences of grades II-IV and III-IV acute GVHD at 100 days were lower in the PTCy group (46% vs. 67%, p = 0.008; 3% vs. 34%, p = 0.003), without statistically significant differences in the 2-year cumulative incidence of chronic moderate-severe GVHD. At 2 years, no significant differences were observed in overall survival, event-free survival, cumulative incidence of relapse, and non-relapse mortality. GVHD was the most frequent cause of NRM in the ATG group. No differences were observed between groups in the composite endpoint of GVHD-free and relapse-free survival. In this study, PTCy combined with additional immunosuppression after MUD/mMUD HSCT showed a reduction of aGVHD rate with safety results comparable to those obtained with the ATG-based prophylaxis.

Transjugular Intrahepatic Portosystemic Shunt for Very Severe Veno-Occlusive Disease/Sinusoidal Obstruction Syndrome (VOD/SOS) after Unmanipulated Haploidentical Hematopoietic Stem Cell Transplantation with Post-transplantation Cyclophosphamide.

Hepatic veno-occlusive disease or sinusoidal obstruction syndrome (VOD/SOS) is a threatening complication after both autologous and allogeneic hematopoietic stem cell transplantation (HSCT), with high mortality rates despite early medical treatment, including the use of defibrotide (DF). We retrospectively analyzed 185 unmanipulated haploidentical (haplo-) HSCT with post-transplantation cyclophosphamide as graft-versus-host disease prophylaxis performed consecutively between 2011 and June 2019 in a single center. Seventeen patients (9.2%) were diagnosed with VOD/SOS. Based on revised European Society for Blood and Marrow Transplantation severity criteria, the VOD/SOS cases were classified as mild in 2 patients (11.7%), moderate in 2 (11.7%), severe in 2 (11.7%), and very severe in 11 (64.9%). Thirteen patients (76%) were treated with DF, including all patients with severe or very severe VOD/SOS, except 1 patient with CNS hemorrhage. Sixteen patients (94%) were alive at day +100 after HSCT. Seven patients (41%) with very severe VOD/SOS were treated with transjugular intrahepatic portosystemic shunt (TIPS) owing to rapid clinical or analytical deterioration or refractory hepatorenal syndrome despite medical treatment, including DF. TIPS insertion was performed at a median time since VOD/SOS diagnosis of 4 days (range, 1 to 28 days) without technical complications in any case. The median hepatic venous pressure gradient before and after TIPS treatment was 24 mmHg (range, 14 to 29 mmHg) and 7 mmHg (range, 2 to 11 mmHg), respectively, with a median drop of 16 mmHg (range, 9 to 19 mmHg). Following TIPS insertion, all patients showed clinical improvement with hepatomegaly, ascites, and renal failure resolution, and all showed analytical improvement with reduced alanine aminotransferase (ALT), creatinine, and international normalized ratio values, except for patient 2, whose indication for TIPS was refractory hepatorenal syndrome with a normal ALT level. The 6 patients who had initiated DF before TIPS insertion completed 21 days of treatment. All patients met the criteria for complete remission (CR) at a median of 8 days after TIPS insertion (range, 2 to 82 days). The 100-day overall survival was 100%. For patients with rapid progressive VOD/SOS, early TIPS insertion allowed completion of DF therapy. The use of TIPS together with DF resulted in CR and no associated complications with no VOD/SOS-associated mortality despite high severity. In our experience, timely and individualized use of TIPS significantly improves outcomes of very severe VOD/SOS after haplo-HSCT. Therefore, TIPS should be promptly considered in rapidly progressive cases.

Drug-to-drug interactions of tyrosine kinase inhibitors in chronic myeloid leukemia patients. Is it a real problem?

With tyrosine kinase inhibitors (TKI), chronic myeloid leukemia (CML) patients are achieving similar rates of survival to the general population and some treatment aspects such as adherence and drug-to-drug interactions (DDI) are becoming increasingly important. Our aim was to investigate the frequency and real clinical consequences of DDI between TKI and concurrent medications in CML. We performed a retrospective multicenter study including 105 patients receiving 134 TKI treatments. Sixty-three patients (60%) had at least one potential DDI. The mean number of concomitant medications was 4.8 (0-19). The mean number of DDI by TKI treatment was 1.2 (0-8); it increased with the number of concomitant medications and age in a significant manner. A total of 159 DDI were detected, involving 55 different drugs. The most common drug classes involved were proton pump inhibitors, statins, and antidepressants. A DDI-related clinical effect (toxicity and/or lack of efficacy) was suspected during the common course of patient follow-up in only five patients (4.7%). This number increased to 20% when data were centrally reviewed. Most of the adverse events (AE) attributed to DDIs were mild. The most common were diarrhea, vomiting, edema, cramps, and transaminitis. Nilotinib and dasatinib showed a tendency towards a higher risk of DDI compared with imatinib. There were no significant differences in AE frequency or in treatment response between patients with or without DDI. Due to their frequency, and their potential to cause clinically relevant effects, DDI are an important aspect of CML management.