Chronic Myeloid Leukemia in a Patient with Previous Idiopathic Thrombocytopenic Purpura: How to Manage Imatinib Together with Eltrombopag

The occurrence of chronic myeloid leukemia (CML), or other myeloproliferative diseases, after the development of idiopathic thrombocytopenic purpura (ITP) is very rare in the current medical literature. Considering the advances in ITP management, and the wide use of new drugs for ITP and CML, we report an unusual case with this association. Our case report focused on a 64-year-old man with long-standing ITP treated with eltrombopag, who developed hyperleukocytosis during follow-up; after specific laboratory exams, it was diagnosed as CML and he began treatment with imatinib. The treatment with eltrombopag was balanced with imatinib to stabilize his platelet count. Data on bcr-abl and JAK2 transcripts were collected and revealed an optimal response with the achievement of negativization of both molecular signatures. We could demonstrate that treatment with imatinib and eltrombopag was well tolerated and allowed complete molecular remission of CML to be achieved, as well as of ITP.

Daratumumab and venetoclax in combination with chemotherapy provide sustained molecular remission in relapsed/refractory CD19, CD20, and CD22 negative acute B lymphoblastic leukemia with KMT2A-AFF1 transcript

Relapsed/refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL) has a very poor prognosis with a median overall survival of four to nine months. Achieving a complete molecular response is most often required to obtain a sustained leukemia-free survival after allogeneic hematopoietic stem cell transplantation. Immunotherapies targeting CD19, CD20, or CD22 are very efficient in achieving this goal. However, in the absence of the expression of these immunotherapeutic targets by lymphoblasts, treatment options are extremely scarce. We report the successful treatment of a 26-year-old man who suffered R/R, CD19, CD20, and CD22 negative B-ALL targeting Bcl-2 and CD38 by combining venetoclax and daratumumab with chemotherapy.

Venetoclax-Ponatinib for T315I/Compound-Mutated Ph+Acute Lymphoblastic Leukemia

The outcome of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) have greatly improved in tyrosine kinase inhibitors (TKIs) era and is just moving to a chemo-free era using dasatinib and blinatumomab (Foà R, N Engl J Med. 2020; Ravandi F, Blood. 2019). However, the outcome of T315I/compound-mutated Ph+ ALL patients is dismal (Cortes JE, N Engl J Med. 2013), representing an unmet need. Recently, Scherr et al reported the curative potential of venetoclax-TKIs-dexamethasone in a BCR-ABL+ mouse model (Scherr M, Leukemia. 2019). Here, we firstly reported outcome of 19 T315I/compound-mutated relapsed/refractory （R/R）Ph+ ALL patients treated with venetoclax(100mg d1, 200mg d2, 400mg d3-28), ponatinib (45mg d1-28) and dexamethasone (0.15mg/kg d1-21,0.075mg/kg d22-28）(VPD regimen) (Figure 1A) between January 2020 and May 2021. They had already received a median of 3 lines of salvage therapy. After one cycle, 17 patients (89.5%) achieved CR/CRi [13 minimal residual disease (MRD)--negative by flow cytometry;11 major molecular remission (MMR);8 complete molecular remission (CMR)] (Figure 1B). Subsequently relapse occurred in 1/6 [allogeneic hematopoietic cell transplantation (allo-HSCT) group)] and 7/11 (VDP consolidation group). At a median follow-up of 259 days, the median EFS and OS of patients from the starting VPD treatment was 242 and 400 days. Adverse events of VPD regimen were listed in Figure 1C. Grade 3-4 neutropenia, anemia and thrombocytopenia occurred in 73.7%,36.8% and 52.6% patients. 5.3% and 16% patients have grade 3-4 rash and infection separately. No tumor lysis syndrome or death occurred. 7/19 patients were treated safety outpatient. Moreover, venetoclax had a strong synergistic effect with ponatinib and dexamethasone on inducing apoptosis of primary blast cells and BaF3 cells expressing p190 BCR/ABL with T315I-mutation in vitro, with a combination index of 0.019 when the suppressing rate is 0.05, while the effect was significant decreased when ponatinib was replaced by dasatinib (Figure 1D-F), a prominent change of mitochondrial membrane potential as well as the cleavage of PARP were also observed in triple-combination treatment group (Figure 1G-H). For T315I/compound-mutated Ph+ ALL, VPD regimen exhibited 89.5% CR/CRi rate, with deep molecular remission (57.9% MMR), while ponatinib alone showed 41% hematologic response (Cortes JE, N Engl J Med. 2013), which supported by the preclinical data suggesting TKIs and venetoclax are highly synergistic in BCR-ABL + cells in vitro (Scherr M, Leukemia. 2019). 7/11 and 1/6 patients subsequently relapsed in continuous VPD and allo-HSCT postremission treatment group separately, suggested bridging to allo-HSCT after remission is warranted. Moreover, novel compounds such as blinatumomab showed a preliminary efficacy (Couturier MA, Leuk Lymphoma. 2021). In summary, VPD regimen provides a novel treatment for T315I/compound-mutated R/R Ph+ALL under a complete oral and chemo-free model. A clinical trial also using similar VPD regimen for treatment of R/R Ph+ ALL is ongoing now (Short NJ, Am J Hematol. 2021). Figure 1 Figure 1. Disclosures No relevant conflicts of interest to declare.

TT52CAR19: Phase 1 Trial of CRISPR/Cas9 Edited Allogeneic CAR19 T Cells for Paediatric Relapsed/Refractory B-ALL

Background 'Off-the-shelf' CAR T cell therapies are being investigated as alternatives to autologous CAR therapy, and can be generated using genome editing from allogeneic donors. Strategies to address HLA barriers include disruption of T cell receptor expression to prevent GVHD and removal of cell surface HLA expression to obviate host mediated rejection, as well as removal of CD52 to create a survival advantage in the presence of Alemtuzumab. In this study, lentiviral mediated CAR19 expression is linked to CRISPR editing through the incorporation of CRISPR guide RNA sequences within the vector 3'Long terminal repeat (LTR). The trial is in progress using pre-manufactured batches of TT52CAR19 T cells. Investigational medicinal product (IMP) Three allogeneic non-HLA matched donor derived CAR19 T cell banks were manufactured from steady state apheresis harvests from registry volunteer donors, using a semi-automated process under compliant conditions. Cells were activated with anti-CD3/CD28 (Transact) reagent and transduced with a lentiviral vector, TT52CAR19, and dual guide sgRNA cassettes targeting the T cell receptor alpha chain (TRAC) and CD52 loci. Next electroporation of Cas9 mRNA elicited transient genome editing, and automated magnetic bead depletion removed remaining TCRαβ+ T cells (mean 0.7%) and enriched CAR19+ T cells (mean 92.8%). Cells were cryopreserved in aliquots suitable for dose-banding and subjected to release testing, including flow cytometry, quantification of copy number (mean 3.83) and exclusion of replication competent lentivirus. Potency of each bank was confirmed in human:murine chimera experiments. Trial sponsorship & approvals The study is open at a single site and is sponsored by Great Ormond Street Hospital NHS trust and is supported by the Medical Research Council and National Institute for Health Research. Clinical trial authorisation was awarded by the MHRA after expert review, and ethical approval including gene therapy advisory committee (GTAC) review, and health research authority (HRA) approval. The study is open label, single arm and non-randomised. Study aims and Objectives The study aims to establish the safety and feasibility of TT52CAR19 for the induction of molecular remission in children with relapsed /refractory CD19-positive B-cell acute lymphoblastic leukaemia (B-ALL) within 28 days, ahead of planned allogeneic haematopoietic stem cell transplantation (allo-SCT). Assessments include time to remission, duration of remission, disease-free survival and overall survival. Expansion, persistence and elimination of TT52CAR19 cells and tracking of immune recovery after allo-SCT is monitored. Recording of complications and toxicities, including possible genotoxic side effects from CRISPR/Cas9 modification provides safety profile information. Eligibility, infusion and outcomes The study plans to treat 10 children aged between 6 months and < 18 years with CD19+ B-ALL quantified at >10 -4 in marrow (by flow or PCR) who are ineligible for autologous therapy. To date 2/4 children screened were found eligible and proceeded to lymphodepletion comprising Fludarabine, Cyclophosphamide and Alemtuzumab followed by a single infusion of 0.8-2.0x10 6 CAR19 T cells and a maximum of 5x10 4/kg TCRαβ T cells. In both cases, there was no GVHD or CRS >grade 1 and recovery of neutrophil counts by d28. Molecular remission was achieved in one child, where TT52CAR19 cells persistence was tracked by chimerism and copy number until further conditioning and allo-SCT. This child remains in remission >6 months later. Conclusions Feasibility of pre-manufacturing off-the-shelf CRISPR/Cas9 edited CAR19 T cells is demonstrated and the trial has provided first in human safety data and preliminary indications of potent anti-leukaemic activity in one of two subjects dosed. Disclosures Qasim: Autolus: Current equity holder in publicly-traded company; Novartis: Honoraria; Servier: Research Funding; Tessa: Membership on an entity's Board of Directors or advisory committees.

Risk-adapted combined therapy with arsenic trioxide and all-trans-retinoic acid for de novo acute promyelocytic leuкaemia

Introduction. Non-chemotherapy for acute promyelocytic leukaemia (APL) with a combination of all-trans-retinoic acid (ATRA) and arsenic trioxide (ATO) provides for a high patient survival rate at lesser toxicity as effectively or superior to standard chemotherapy programmes.Aim — assessment of the ATO–ATRA risk-adapted exposure protocol in management of de novo acute promyelocytic leucaemia.Materials and methods. A prospective study included 51 primary APL patients aged 18–76 years. The program included remission induction (ATO 0.15 mg/kg intravenously, ATRA 45 mg/m2 orally) for 30–60 days in a low-risk (until remission) and 60 days — in a high-risk cohort that had idarubicin therapy added on days 2 and 4. Remission consolidation was attained with four (low-risk) or five (high-risk) courses. Minimal residual disease was monitored with real-time PCR at all phases.Results. The high-risk cohort was assigned 15 (29.4 %), the low-risk cohort — 36 (70.6 %) patients. Therapy induction till APL morphological remission was performed in 48/51 (94 %) patients. Molecular APL remission was achieved in 47 (92 %) patients, 100 % in the low-risk and 80 % in high-risk cohort. Early mortality was 6 % (n = 3), death in remission — 2 % (n = 1). Differentiation syndrome (DS) occurred in 16 (31.7 %) patients, more frequently in the high-risk vs. low-risk cohort (53.3 % and 22.2 %, respectively, p = 0.05; odds ratio 4.0 [1.1–14.4]). DS developed on days 1–20 (3 days median) of therapy. DS risk factors: a high-risk status, haemorrhagic syndrome and infection at the disease onset. A median follow-up time in survivors was 12.9 months (2.5–34.3), a six-month overall survival — 92 % (95 % CI: 85–100 %). A six-month overall survival was 100 and 73 % in the low- and high-risk cohorts, respectively (95 % CI: 54–100 %, p = 0.001). APL relapse not registered, 47 (92 %) patients survived and achieved the first molecular remission.Conclusion. A differentiated risk-adapted approach to APL therapy with cytostatic treatment added in high-risk patients only provided for a 100 % molecular remission and relapse-free survival. Therapy failures (early mortality and death in remission) affected high-risk patients due to a severe individual condition at the time of APL diagnosis.

Case report: MPN-eo with balanced rearrangement of MPRIP-PDGFRB t(5;17)(q32;p11), responding to low dose imatinib

We present a young patient with a rare eosinophilic myeloproliferative neoplasm MPN-eo with a balanced rearrangement of MPRIP-PDGFRB t(5;17)(q32;p11). This fusion gene was reported in only one other case in 2015. A personalized molecular test was developed with the diagnostic material of the patient. Our patient is in complete cytogenetic and molecular remission under low dose imatinib, two years after treatment initiation.

Molecular remission at T cell level in patients with rheumatoid arthritis

While numerous disease-modifying anti-rheumatic drugs (DMARDs) have brought about a dramatic paradigm shift in the management of rheumatoid arthritis (RA), unmet needs remain, such as the small proportion of patients who achieve drug-free status. The aim of this study was to explore key molecules for remission at the T cell level, which are known to be deeply involved in RA pathogenesis, and investigate the disease course of patients who achieved molecular remission (MR). We enrolled a total of 46 patients with RA and 10 healthy controls (HCs). We performed gene expression profiling and selected remission signature genes in CD4+ T cells and CD8+ T cells from patients with RA using machine learning methods. In addition, we investigated the benefits of achieving MR on disease control. We identified 9 and 23 genes that were associated with clinical remission in CD4+ and CD8+ T cells, respectively. Principal component analysis (PCA) demonstrated that their expression profiling was similar to those in HCs. For the remission signature genes in CD4+ T cells, the PCA result was reproduced using a validation cohort, indicating the robustness of these genes. A trend toward better disease control was observed during 12 months of follow-up in patients treated with tocilizumab in deep MR compared with those in non-deep MR, although the difference was not significant. The current study will promote our understanding of the molecular mechanisms necessary to achieve deep remission during the management of RA.

Indeterminate and oncogenic potential: CHIP vs CHOP mutations in AML with NPM1 alteration

In AML patients, recurrent mutations were shown to persist in remission, however, only some have a prognostic value and persistent mutations might therefore reflect a re-established premalignant state or truly active disease causing relapse. We aimed to dissect the nature of co-mutations in NPM1 mutated AML where the detection of NPM1 transcripts allows highly specific and sensitive detection of complete molecular remission (CMR). We analysed 150 consecutive patients who achieved CMR following intensive treatment by next generation sequencing on paired samples at diagnosis, CMR and relapse (38/150 patients). Patients with persistence or the acquisition of non-DTA (DNMT3A, TET2, ASXL1) mutations at CMR (23/150 patients, 15%) have a significantly worse prognosis (EFS HR = 2.7, p = 0.003; OS HR = 3.6, p = 0.012). Based on clonal evolution analysis of diagnostic, CMR and relapse samples, we redefine pre-malignant mutations and include IDH1, IDH2 and SRSF2 with the DTA genes in this newly defined group. Only the persistence or acquisition of CHOP-like (clonal hematopoiesis of oncogenic potential) mutations was significantly associated with an inferior outcome (EFS HR = 4.5, p = 0.0002; OS HR = 5.5, p = 0.002). Moreover, the detection of CHOP-like mutations at relapse was detrimental (HR = 4.5, p = 0.01). We confirmed these findings in a second independent whole genome sequencing cohort.

Complete hematological and major molecular response through treatment with ultra-low dose Interferon alpha 2 in polycythemia vera: a case report

Early treatment of polycythemia vera with ultra-low-dose interferon-α 2a is well tolerated and results in complete hematologic and major molecular remission and a strong reduction of all symptoms, especially pruritus and fatigue.