Vemurafenib plus Rituximab in Refractory or Relapsed Hairy-Cell Leukemia.

BACKGROUND: Hairy-cell leukemia (HCL) is a CD20+ indolent B-cell cancer in which a BRAF V600E kinase-activating mutation plays a pathogenetic role. In clinical trials involving patients with refractory or relapsed HCL, the targeting of BRAF V600E with the oral BRAF inhibitor vemurafenib led to a response in 91% of the patients; 35% of the patients had a complete response. However, the median relapse-free survival was only 9 months after treatment was stopped. METHODS: In a phase 2, single-center, academic trial involving patients with refractory or relapsed HCL, we assessed the safety and efficacy of vemurafenib (960 mg, administered twice daily for 8 weeks) plus concurrent and sequential rituximab (375 mg per square meter of body-surface area, administered for 8 doses over a period of 18 weeks). The primary end point was a complete response at the end of planned treatment. RESULTS: Among the 30 enrolled patients with HCL, the median number of previous therapies was 3. A complete response was observed in 26 patients (87%) in the intention-to-treat population. All the patients who had HCL that had been refractory to chemotherapy (10 patients) or rituximab (5) and all those who had previously been treated with BRAF inhibitors (7) had a complete response. Thrombocytopenia resolved after a median of 2 weeks, and neutropenia after a median of 4 weeks. Of the 26 patients with a complete response, 17 (65%) were cleared of minimal residual disease (MRD). Progression-free survival among all 30 patients was 78% at a median follow-up of 37 months; relapse-free survival among the 26 patients with a response was 85% at a median follow-up of 34 months. In post hoc analyses, MRD negativity and no previous BRAF inhibitor treatment correlated with longer relapse-free survival. Toxic effects, mostly of grade 1 or 2, were those that had previously been noted for these agents. CONCLUSIONS: In this small study, a short, chemotherapy-free, nonmyelotoxic regimen of vemurafenib plus rituximab was associated with a durable complete response in most patients with refractory or relapsed HCL. (Funded by the European Research Council and others; HCL-PG03 EudraCT number, 2014-003046-27.).

Tagraxofusp in myeloid malignancies.

Tagraxofusp (or SL-401) is a recombinant molecule composed of human interleukin-3 that binds CD123 on neoplastic cells fused to a truncated diphtheria toxin (DT). Tagraxofusp's most significant success has come from studies involving patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN), an aggressive disease that is usually refractory to conventional chemotherapy. Tagraxofusp had an acceptable safety profile and high efficacy in early phase I/II studies on patients with BPDCN. Another phase II study confirmed the good response rates, resulting in Food and Drugs Administration and European Medicine Agency approval of tagraxofusp for the treatment of BPDCN. Considering its high efficacy and its manageable safety profile, tagraxofusp has been suddenly explored in other myeloid malignancies with high expression of cell surface CD123, both in monotherapy or combination strategies. The triplet tagraxofusp-azacytidine-venetoclax appears to be of particular interest among these combinations. Furthermore, combination strategies may be used to overcome tagraxofusp resistance. The downregulation of DPH1 (diphthamide biosynthesis 1), the enzyme responsible for the conversion of histidine 715 on eEF2 to diphthamide, which is then the direct target of ADP ribosylation DT, is typically associated with this resistance phenomenon. It has been discovered that azacitidine can reverse DHP1 expression and restore sensitivity to tagraxofusp. In conclusion, the success of tagraxofusp in BPDCN paved the way for its application even in other CD123-positive malignancies. Nowadays, several ongoing trials are exploring the use of tagraxofusp in different myeloid neoplasms. This review aims to summarize the actual role of tagraxofusp in BPDCN and other CD123-positive myeloid malignancies.

Teclistamab-cqyv in multiple myeloma.

Multiple myeloma (MM) is an incurable neoplasm characterized by significant morbidity and mortality. Despite advances in treatment, MM patients eventually experienced a relapse of the disease. Penta-drug refractory patients continue to be the hard core of relapsed/refractory (RR) settings. Teclistamab-cqyv is a humanized IgG4 antibody and a bispecific BCMA-director CD3 T-cell engager. It recruits endogenous T cells, by targeting CD3 receptors expressed on their surface, resulting in their activation against BCMA, an antigen expressed by plasma cells. US Food and Drug Administration (FDA) and European Medicines Agency (EMA) have approved Teclistamab-cqyv in monotherapy for the treatment of RRMM patients who have received at least three prior therapies, including immunomodulatory drugs (IMiDs), proteasome inhibitors (PIs), and anti-CD38 monoclonal antibodies (MoAbs) and have demonstrated disease progression during the last therapy. Its effectiveness was demonstrated in a pivotal clinical trial where the overall response rate (ORR) reached 60%. Other clinical studies are currently ongoing to investigate the association of the bispecific antibody with novel drugs with encouraging preliminary results, especially in the setting of heavily pretreated patients. In this review, the authors will provide a comprehensive overview of the drug, including its mechanism of action, major clinical trials, and future perspectives.

Myelodysplastic syndromes del(5q): Pathogenesis and its therapeutic implications.

Myelodysplastic syndromes (MDS) encompass a heterogeneous set of acquired bone marrow neoplastic disorders characterized by ineffective hematopoiesis within one or more bone marrow lineages. Nearly half of MDS patients carry cytogenetic alterations, with del(5q) being the most prevalent. Since its first description, del(5q) was consistently correlated with a typical clinical phenotype marked by anemia, thrombocytosis, and a low risk of evolving into acute leukemia. Presently, the World Health Organization (WHO) classification of myeloid neoplasms recognizes a specific subtype of MDS known as "myelodysplastic neoplasm with low blast and isolated del(5q)" identified by the sole presence of 5q deletion or in combination with one other abnormality excluding -7/del(7q). Several studies have sought to unravel the biological processes triggered by del(5q) in the development of MDS, revealing the involvement of various genes localized in specific regions of chromosome 5 referred to as common deleted regions (CDR). This intricate biological landscape makes the MDS cells with del(5q) exceptionally sensitive to lenalidomide. Several studies have confirmed the efficacy of lenalidomide in this context. Regrettably, the response to lenalidomide is not conclusive, prompting ongoing research into biological mechanisms that drive patients toward leukemia and strategies to circumvent lenalidomide resistance and disease progression.

Myelodysplastic syndromes with ring sideroblasts.

Myelodysplastic syndromes (MDS) are acquired bone marrow malignant disorders characterized by ineffective hematopoiesis, resulting from a complex interaction between genetic and epigenetic mutations, alterations of the marrow microenvironment, and the immune system. In 2001, the World Health Organization (WHO) proposed a classification that integrates morphologic and genetic information, considering the MDS with ring sideroblasts (MDS-RS) as a distinct entity. Considering the strong association between MDS-RS and SF3B1 mutation and its importance in the development of MDS, the last WHO classification replaced the prior entity of MDS-RS with MDS with SF3B1 mutation. Several studies were performed to explore this genotype-phenotype correlation. Mutant SF3B1 protein deregulates the expression of genes implicated in developing hematopoietic stem and progenitor cells. Of paramount importance are PPOX and ABCB7 involved in iron metabolism. Another essential role in hemopoiesis is played by the transforming growth factor-beta (TGF-ß) receptor. This gene exerts its effects on SMAD pathways, regulating hematopoiesis through effects on balancing proliferation and apoptosis cell inactivity, differentiation, and migration. Luspatercept (ACE-536) is a soluble fusion protein that inhibits molecules in the TGF-ß superfamily. Since its structure resembles the TGF-ß family receptor, it catches TGF-ß superfamily ligands before binding to the receptor, resulting in reduced activation of SMAD signaling, thus enabling erythroid maturation. Luspatercept was investigated in the phase III trial MEDALIST, showing promising efficacy in treating anemia compared to placebo. Nowadays, further studies are needed to explore the real potential of luspatercept, investigating the biological features likely associated with treatment response, the potential use in combination treatments, and its role in the treatment of naïve MDS.

Iron chelation therapy.

Iron overload is a pathological condition resulting from a congenital impairment of its regulation, increased intestinal iron absorption secondary to bone marrow erythroid hyperplasia, or a chronic transfusional regimen. In normal conditions, intracellular and systemic mechanisms contribute to maintaining iron balance. When this complex homeostatic mechanism fails, an iron overload could be present. Detecting an iron overload is not easy. The gold standard remains the liver biopsy, even if it is invasive and dangerous. Identifying iron using noninvasive techniques allowed a better understanding of the rate of iron overload in different organs, with a low risk for the patient. Estimating serum ferritin (mg/L) is the easiest and, consequently, the most employed diagnostic tool for assessing body iron stores, even if it could be a not specific method. The most common hematological causes of iron overload are myelodysplastic syndromes, sickle cell disease, and thalassemia. In all of these conditions, three drugs have been approved for the treatment of iron overload: deferiprone, deferoxamine, and deferasirox. These chelators have been demonstrated to help lower tissue iron levels and prevent iron overload complications, improving event-free survival (EFS). Nowadays, the decision to start chelation and which chelator to choose remains the joint decision of the clinician and patient.

Disappearance of Bone Marrow Fibrosis in a Patient with Chronic Myeloid Leukemia Treated with Dasatinib.

We report a case of a chronic myeloid leukemia patient showing progressive bone marrow fibrosis and anemia during imatinib therapy. Given the loss of major molecular response, we switched treatment to dasatinib 100 mg daily, observing a reduction in BCR-ABL transcript, a significant improvement of anemia, and a gradual disappearance of fibrosis. After 7 years of dasatinib therapy the patient maintains a complete cytogenetic response and a deep molecular response; the last bone biopsy confirmed the absence of fibrosis.

Momelotinib in myelofibrosis.

INTRODUCTION: Myelofibrosis (MF) is a hematologic disease characterized by bone marrow fibrosis, cytopenias, splenomegaly, and constitutional symptoms. Recent years have seen the emergence of novel therapeutic agents, notably ruxolitinib and fedratinib, which target the Janus kinases (JAK) pathway. However, their myelosuppressive effect coupled with the persistence, and even worsening anemia remains a significant challenge, leading usually to treatment discontinuation. AREAS COVERED: This review focuses on Momelotinib (MMB), a unique JAK inhibitor that has shown promise in MF treatment, particularly in improving anemia. MMB inhibits type 1 kinase activin A receptor or activin receptor-like kinase-2 (ACVR1/ALK2), with consequent rebalancing of the SMAD pathways and reduced transcription of hepcidin. Moreover, it seems that MMB could reduce the serum levels of several inflammatory cytokines responsible for anemia. Clinical trials have demonstrated MMB's efficacy in reducing spleen size, alleviating symptoms, and improving anemia, with a favorable safety profile compared to other JAK inhibitors, both in treatment-naïve and in pre-treated patients. EXPERT OPINION: Due to its mechanism of action, MMB represents a valuable therapeutic option in MF, addressing the clinical challenge of anemia and potentially improving outcomes for patients with hematologic malignancies. Ongoing research explores MMB's potential in acute myeloid leukemia and combination therapies.

Selinexor in multiple myeloma.

INTRODUCTION: Selinexor, an XPO1 inhibitor, has emerged as a promising therapeutic option in the challenging landscape of relapsed/refractory multiple myeloma (RRMM). AREAS COVERED: This article provides a review of selinexor, with a focus on available clinical studies involving MM patients and its safety profile. Clinical trials, such as STORM and BOSTON, have demonstrated its efficacy, particularly in combination regimens, showcasing notable overall response rates (ORR) and prolonged median progressionfree survival (mPFS). Selinexor's versatility is evident across various combinations, including carfilzomibdexamethasone (XKd), lenalidomidedexamethasone (XRd), and pomalidomidedexamethasone (XPd), with efficacy observed even in tripleclass refractory and highrisk patient populations. However, challenges, including resistance mechanisms and adverse events, necessitate careful management. Realworld evidence also underscores selinexor's effectiveness in RRMM, though dose adjustments and supportive measures remain crucial. Ongoing trials are exploring selinexor in diverse combinations and settings, including pomalidomidenaïve patients and postautologous stem cell transplant (ASCT) maintenance. EXPERT OPINION: The evolving landscape of selinexor's role in the sequencing of treatment for RRMM, its potential in highrisk patients, including those with extramedullary disease, as revealed in the most recent international meetings, and ongoing investigations signal a dynamic era in myeloma therapeutics. Selinexor emerges as a pivotal component in multidrug strategies and innovative combinations.

The potential of triplet combination therapies for patients with FLT3-ITD -mutated acute myeloid leukemia.

INTRODUCTION: Acute myeloid leukemia (AML) encompasses a heterogeneous group of aggressive myeloid malignancies, where FMS-like tyrosine kinase 3 (FLT3) mutations are prevalent, accounting for approximately 25-30% of adult patients. The presence of this mutation is related to a dismal prognosis and high relapse rates. In the lasts years many FLT3 inhibitors have been developed. AREAS COVERED: This review provides a comprehensive overview of FLT3mut AML, summarizing the state of art of current treatment and available data about combination strategies including an FLT3 inhibitor. EXPERT OPINION: In addition, the review discusses the emergence of drug resistance and the need for a nuanced approaches in treating patients who are ineligible for or resistant to intensive chemotherapy. Specifically, it explores the historical context of FLT3 inhibitors (FLT3Is) and their impact on treatment outcomes, emphasizing the pivotal role of midostaurin, as well as gilteritinib and quizartinib, and providing detailed insights into ongoing trials exploring the safety and efficacy of novel triplet combinations involving FLT3Is in different AML settings.

Investigational CXCR4 inhibitors in early phase development for the treatment of hematological malignancies.

INTRODUCTION: CXCR4/CXCL12 axis regulates cell proliferation, survival, and differentiation, as well as the homing and mobilization of hematopoietic stem cells (HSCs) from bone marrow niches to the peripheral blood. Furthermore, CXCR4 and CXCL12 are key mediators of cross-talk between hematological malignancies and their microenvironments. CXCR4 overexpression drives disease progression, boosts tumor cell survival, and promotes chemoresistance, leading to poor prognosis. AREAS COVERED: In light of these discoveries, scientific investigations, and clinical trials have underscored the therapeutic promise found in small-molecule antagonists like plerixafor, peptides/peptidomimetics, such as BKT140, monoclonal antibodies like PF-06747143 and ulocuplumab, as well as microRNAs. Their efficacy is evident in reducing tumor burden, inducing apoptosis and sensitizing malignant cells to conventional chemotherapies. This overview delves into the pathogenic role of the CXC4/CXCL12 axis in hematological neoplasms and examines the clinical application of key CXCR4 antagonists. EXPERT OPINION: The information collectively emphasizes the potential of CXCR4 antagonists as a therapeutic strategy for hematologic malignancies, showcasing advancements in preclinical and clinical studies. As these therapeutic strategies progress through clinical trials, their potential to reshape the prognosis of hematologic malignancies will become increasingly apparent.

Glasdegib for the treatment of acute myeloid leukemia.

INTRODUCTION: Over the last few years, substantial progress has been made in the management of acute myeloid leukemia (AML). The first changes in the management of AML date back to last 2000s with the advent of hypometilant agents, later with Bcl2 inhibitor venetoclax, and Fms-like tyrosine kinase 3 (FLT3) inhibitors (midostaurin and gilteritinib), and more recently with IDH1/2 inhibitors (ivosidenib and enasidenib) and the hedgehog (HH) pathway inhibitor glasdegib. AREAS COVERED: Glasdegid, formerly PF-04449913 or PF-913, acts as a smoothened (SMO) inhibitor and has been recently approved in combination with low-dose cytarabine (LDAC) by FDA and EMA for the treatment of naïve AML patients unfit for intensive chemotherapy.Several studies have explored the efficacy and safety of glasdegib, as a single agent or in combination with other drugs, in both the setting of relapsed/refractory and naïve AML patients, confirming its efficacy in controlling disease and safety profile. EXPERT OPINION: All these trials suggest that glasdegib seems to be an ideal partner for both classic chemotherapy and biological treatments (such as therapy with FLT3 inhibitors). Further studies are needed to better understand which patients are more likely to respond to glasdegib.

Ivosidenib in acute myeloid leukemia.

INTRODUCTION: Traditional treatment strategies for acute myeloid leukemia (AML) have primarily relied on standard chemotherapy regimens for four decades. Indeed, the landscape of AML therapy has evolved substantially in recent years, mainly due to the introduction of hypomethylating agents and small molecules.Bcl2 inhibitor venetoclax, Fms-like tyrosine kinase 3 (FLT3) inhibitors such as midostaurin and gilteritinib, and isocitrate dehydrogenases 1 and 2 (IDH1 and IDH2) inhibitors ivosidenib and enasidenib, as well as hedgehog (HH) pathway inhibitor glasdegib represented a significant step forward in AML therapeutic armamentarium. Smoothened (SMO) inhibitor in combination with low-dose cytarabine marks a recent milestone. AREAS COVERED: Ivosidenib, the first-in-class, selective, allosteric IDH1R132 inhibitor, showed the capability to induce in vitro differentiation of primary mIDH1 AML blasts. Clinical data highlighted its exceptional safety profile, as a standalone therapy and in combination strategy. Additionally, comprehensive studies consistently demonstrated its effectiveness, both in monotherapy and in association with chemotherapy. EXPERT OPINION: The identified ivosidenib's strengths, including its remarkable safety record and ability to yield positive therapeutic outcomes, position it as an ideal partner for both classic chemotherapy and biological treatments, i.e. hypometilant agents and/or venetoclax. Further studies are warranted to explore strategies for overcoming the occurrence of ivosidenib resistance.

Safety and efficacy of caplacizumab in a case of thrombotic thrombocytopenic purpura in the postpartum period.

Thrombotic thrombocytopenic purpura (TTP) is a rare and life-threatening disease for which pregnancy and the postpartum period represent risk factors. Here, we present the case of a 39-year-old woman at the 31st week of gestation, who presented with cutaneous haemorrhagic symptoms. The complete blood count showed anaemia, thrombocytopenia, increase in haemolysis indices and undetectable ADAMTS13 activity. Acquired TTP was diagnosed, and she started daily plasma exchange (PEX) and methylprednisolone. After 5 days, an emergency caesarean section was performed with success because of pathologic cardiotocographic findings. After 7 days of PEX, the patient showed an initial laboratoristic improvement; unfortunately, 3 days later, she had a recurrence of disease and started daily PEX, caplacizumab and steroid, obtaining a haematological improvement. No literature data about caplacizumab use in pregnant or breastfeeding patients are available. In the present study, we describe that caplacizumab in the postpartum period could be well tolerated and effective.

Safe and Effective Administration of Caplacizumab in COVID-19-Associated Thrombotic Thrombocytopenic Purpura.

Thrombotic thrombocytopenic purpura (TTP) is a potentially life-threatening, rare acute thrombotic microangiopathy (TMA), caused by a severe ADAMTS13 deficiency. As the COVID-19 pandemic rapidly spread around the globe, much data about the pathogenicity of this virus were published. Soon after the detection of the first cases of COVID-19, it was clear that there was a wide range of COVID coagulopathy manifestations, such as deep venous thrombosis, pulmonary thromboembolism, and thrombotic microangiopathies. In the literature, little data have been reported about the association between TTP and COVID-19, and the treatment of COVID-19-associated TTP is still under debate. Here we present the case of a 46-year-old woman who developed a COVID-associated TTP, successfully treated with plasma exchange (PEX), steroids, and caplacizumab.

Eltrombopag treatment for severe immune thrombocytopenia during pregnancy: a case report.

Primary immune thrombocytopenia (ITP) is an autoimmune disorder characterized by isolated thrombocytopenia (platelet count <100 × 109/l) in the absence of other causes or disorders associated. The incidence of ITP in pregnancy is one to two cases per 1000 gestations. ITP could be diagnosed before or during pregnancy; sometimes a relapse of a previously diagnosed ITP can occur. Intravenous immune globulins (IVIg) and corticosteroids are the standard frontline therapy because of their well known safety profile either for the mother or for the neonate. Treatments for refractory patients are limited by potential fetal risk. We report the case of a patient with ITP along pregnancy, refractory to corticosteroids and IVIg, successfully treated with, the thrombopoietin receptor agonist (TPO-RA) eltrombopag. Patient received this compound for almost the whole pregnancy and in particular for the whole first trimester, without any complication for the mother and the neonate. Although transient administration of TPO-RAs in pregnancy seems to be well tolerated, their use during the whole gestation is still controversial; this is the reason of the description of this case, which did not show any complications, and thus it could add useful information on this field.

Therapeutic approaches for newly diagnosed multiple myeloma patients in the era of novel drugs.

The treatment of newly diagnosed multiple myeloma (MM) has evolved rapidly over recent years. The availability of new effective drugs with novel mechanisms of action, such as thalidomide, lenalidomide and bortezomib in the last decade, has resulted in a new scenario expected to impact favorably on the outcome of patients with MM. The introduction of new drugs in the treatment of patients eligible for autologous stem cell transplantation (ASCT) has allowed for a significant increase of complete response rate with a positive impact on progression-free survival. In patients not eligible for ASCT, randomized trials have shown that both thalidomide and bortezomib when combined with melphalan and prednisone (MP) are superior to MP and are now considered the standard of care. Ongoing trials are assessing whether MP plus lenalidomide or the combination of lenalidomide plus dexamethasone should be considered an attractive treatment option, while additional studies are needed to determine the role of routine maintenance or consolidation therapy with these new drugs. This new therapeutic armamentarium in light of adequate prophylaxis and supportive care allows clinicians to greatly improve the survival perspectives for both young and elderly patients. In this review, we report updated data for the front-line therapy of MM, examining the role of new drugs either when administered as induction therapy before ASCT in younger patients or when combined with alkylating agents for the treatment of older patients. The most relevant articles on therapy of MM published from November 1982 to January 2010 (selected through PubMed), and recent meeting abstracts were used as sources for this review.

Long-Term Remission Achieved by Ponatinib and Donor Lymphocytes Infusion in a Ph+ Acute Lymphoblastic Leukemia Patient in Molecular Relapse After Allogenic Stem Cell Transplant and Dasatinib: A Case Report.

Currently, the prognosis of Ph+ acute lymphoblastic leukemia (Ph+ ALL) patients relapsing after an allogenic hematopoietic stem cell transplantation (allo-SCT) remains poor, with few therapeutic options available. Here we present the case of a 32 years old patient with dasatinib-resistant post-transplant molecular relapse of ALL, who received, as second-line therapy, the combination of ponatinib and donor lymphocyte infusion (DLI). The therapy was safe and the patient achieved a sustained minimal residual disease negative disease, still ongoing after 22 months, which was accompanied by several changes in the immune populations distribution within the bone marrow (i.e., the increase in the CD8/CD4 lymphocytes ratio). Our report provides evidence of the efficacy of the third generation TKI inhibitor ponatinib in combination with DLI as second line therapy for Ph+ ALL relapsing after an allo-SCT.

Definition of progression risk based on combinations of cellular and molecular markers in patients with Binet stage A chronic lymphocytic leukaemia.

IGHV mutational status and ZAP-70 or CD38 expression correlate with clinical course in B-cell chronic lymphocytic leukaemia (CLL). The three markers may be discordant in the single case and there is no consensus on their combined use in clinical practise. This multicenter study investigated this issue. Two-hundred and sixty-two Binet stage A patients were studied for the three markers. Sixty patients were profiled with HG-U133A gene expression chips. Disease progression was determined by time from diagnosis to treatment (TTT). The probability of being treatment-free at 3 years was significantly shorter in patients with unmutated IGHV genes (IGHVunmut 66% vs. 93%, chi square of log-rank = 30, P < 0.0001), ZAP-70 positive (ZAP-70pos 73% vs. 96%, chi square of log-rank = 8.2, P = 0.004) or CD38-positive cells (CD38pos 68% vs. 91%, chi square of log-rank = 21, P < 0.0001). Cox multivariate regression analysis showed that the three markers had an independent predictive value for TTT of similar power. A prognostic system based on presence of none (low-risk), one (intermediate-risk) or two or three (high-risk) markers was generated. Based on such criteria, 56%, 23% and 21% of cases were clustered in low (HR = 1), intermediate [HR = 2.8, 95% confidence interval (CI) 2.4-5.8] and high-risk group (HR = 8.0, 95% CI 3.9-16.2). Specific transcriptional patterns were significantly associated with risk groups.