Ruxolitinib-associated infections: A systematic review and meta-analysis

How I individualize selection of JAK inhibitors for patients with myelofibrosis

ABSTRACT

The advent of Janus kinase inhibitors (JAKis) inaugurated a novel era in the treatment of myelofibrosis (MF), a myeloproliferative neoplasm with heterogeneous clinical manifestations. Four JAKis have been approved for intermediate or high-risk MF, in the United States. Regulatory approval of the first JAK1/2 inhibitor, ruxolitinib, in 2011, transformed the landscape of MF by markedly controlling splenomegaly and constitutional symptoms, improving patients' quality of life, and prolonging survival. Fedratinib, the second approved JAKi, is preferred in the second-line setting. Ruxolitinib and fedratinib can cause myelosuppression and are recommended for patients with the myeloproliferative phenotype. The approval of 2 less-myelosuppressive JAKis, pacritinib and momelotinib, provided essential treatment options for patients with severe thrombocytopenia and anemia, respectively. Momelotinib and pacritinib are potent activin A receptor, type 1 inhibitors with consequent significant benefits for patients with anemia. Transfusion independence was achieved with momelotinib in patients who were severely anemic, and the association of transfusion independence with prolonged overall survival was demonstrated. Judicious treatment decisions regarding JAKis can be made with in-depth understanding of the pivotal clinical trials that evaluated JAKis and their therapeutic attributes and should be guided by the dominant clinical manifestations and the type/degree of cytopenia(s) (myeloproliferative/cytopenic phenotypes). This article reviews our clinical approach to treatment with JAKis and their sequencing in patients with MF by presenting 3 clinical vignettes.

SOHO State of the Art Updates and Next Questions | Choosing and Properly Using a JAK Inhibitor in Myelofibrosis

Myelofibrosis (MF) is a chronic myeloid neoplasm characterized by myeloproliferation, bone marrow fibrosis, splenomegaly, and constitutional symptoms related to pro-inflammatory cytokine signaling. Biologically, MF is characterized by constitutive activation of JAK-STAT signaling; accordingly, JAK inhibitors have been rationally developed to treat MF. Following the initial approval of ruxolitinib in 2011, three additional agents have been approved: fedratinib, pacritinib, and momelotinib. As these therapies are noncurative, allogeneic stem cell transplantation remains a key treatment modality and patients with MF who are deemed candidates should be referred to a transplant center. This potentially curative but toxic approach is typically reserved for patients with higher-risk disease, and JAK inhibitors are recommended in the pretransplant setting. JAK inhibitors have proven effective at managing splenomegaly and constitutional symptoms and should be started early in the disease course in patients presenting with these clinical manifestations; asymptomatic patients may initially be followed with close surveillance. Drug-related myelosuppression has been a challenge with initial JAK inhibitors, particularly in patients presenting with a cytopenic phenotype. However, newer agents, namely pacritinib and momelotinib, have proven more effective in this setting and are approved for patients with significant thrombocytopenia and anemia, respectively. Resistance or disease progression is clinically challenging and may be defined by several possible events, such as increasing splenomegaly or progression to accelerated or blast phase disease. However, with multiple JAK inhibitors now approved, sequencing of these agents appears poised to improve outcomes. Additionally, novel JAK inhibitors and JAK inhibitor-based combinations are in clinical development.

Real World Management of Cytopenias and Infections in Patients With Myelofibrosis Treated With Ruxolitinib

Introduction

Ruxolitinib was the first JAK2 inhibitor approved for the treatment of primary and secondary myelofibrosis. It is currently used worldwide as first-line therapy for advanced disease (intermediate-2 and high-risk) and is effective in polycythaemia vera (PV) and essential thrombocythaemia (ET), but not funded for this indication in many countries. Ruxolitinib has proven benefits with respect to symptom control, reduction in spleen size and prolongation of survival; however, it rarely induces a substantial reduction in allele burden and never provides a cure. Moreover, there are frequently encountered adverse effects and dosing issues that require careful management to optimise its therapeutic benefit.

Methods and Results

In this case-based review, we use seven informative common clinical scenarios to discuss appropriate investigation and management of cytopenias and infection issues.

Conclusions

We make recommendations based on 15 years of experience in using ruxolitinib and other JAK inhibitors for the treatment of myelofibrosis. We discuss when allogeneic haematopoietic stem cell transplantation (AHSCT) should be considered and some of the currently available alternative JAK inhibitors and trial options when AHSCT is not an option.

Malignant JAK-signaling: at the interface of inflammation and malignant transformation

The JAK pathway is central to mammalian cell communication, characterized by rapid responses, receptor versatility, and fine-tuned regulation. It involves Janus kinases (JAK1, JAK2, JAK3, TYK2), which are activated when natural ligands bind to receptors, leading to autophosphorylation and activation of STAT transcription factors [1, 2]. JAK-dependent signaling plays a pivotal role in coordinating cell communication networks across a broad spectrum of biological systems including development, immune responses, cell growth, and differentiation. JAKs are frequently mutated in the aging hematopoietic system [3, 4] and in hematopoietic cancers [5]. Thus, dysregulation of the pathway results in various diseases, including cancers and immune disorders. The binding of extracellular ligands to class I and II cytokine receptors initiates a critical signaling cascade through the activation of Janus kinases (JAKs). Upon ligand engagement, JAKs become activated and phosphorylate specific tyrosine residues on the receptor, creating docking sites for signal transducer and activator of transcription (STAT) proteins. Subsequent JAK-mediated phosphorylation of STATs enables their dimerization and nuclear translocation, where they function as transcription factors to modulate gene expression. Under physiological conditions, JAK-signaling is a tightly regulated mechanism that governs cellular responses to external cues, such as cytokines and growth factors, ensuring homeostasis and maintaining the functional integrity of tissues and organs. Highly defined regulation of JAK-signaling is essential for balancing cellular responses to inflammatory stimuli and growth signals, thus safeguarding tissue health. In contrast, dysregulated JAK-signaling results in chronic inflammation and unrestrained cellular proliferation associated with various diseases. Understanding the qualitative and quantitative differences at the interface of physiologic JAK-signaling and its aberrant activation in disease is crucial for the development of targeted therapies that precisely tune this pathway to target pathologic activation patterns while leaving homeostatic processes largely unaffected. Consequently, pharmaceutical research has targeted this pathway for drug development leading to the approval of several substances with different selectivity profiles towards individual JAKs. Yet, the precise impact of inhibitor selectivity and the complex interplay of different functional modules within normal and malignant cells remains incompletely understood. In this review, we summarize the current knowledge on JAK-signaling in health and disease and highlight recent advances and future directions in the field.

Selinexor plus ruxolitinib in JAK inhibitor treatment-naïve myelofibrosis: SENTRY Phase 3 study design

Selinexor is an investigational, selective oral XPO1 inhibitor that may inhibit myelofibrosis (MF)-relevant JAK/STAT and non-JAK/STAT pathways with potential synergy with ruxolitinib. SENTRY (XPORT-MF-034; NCT04562389) is a Phase 1/3 study evaluating safety and efficacy of selinexor plus ruxolitinib for treatment of patients with JAK inhibitor (JAKi) treatment-naïve MF. The Phase 1 open label portion of the study included a 3 + 3 dose escalation and dose expansion, with no dose limiting toxicities observed. Described here is the Phase 3 randomized, double-blind, placebo-controlled study designed to evaluate selinexor+ruxolitinib versus placebo+ruxolitinib in patients with JAKi treatment-naïve MF. Approximately 350 patients will be enrolled. Primary endpoints will evaluate spleen volume reduction ≥ 35% and absolute mean change in total symptom score from baseline to week 24.Clinical Trial Registration: NCT04562389 (ClinicalTrials.Gov).

Diagnosis and Treatment of Polycythemia Vera: A Review

Importance

Polycythemia vera (PV), a myeloproliferative neoplasm characterized by an increased red blood cell mass and increased risk of thrombosis, affects approximately 65 000 people in the US, with an annual incidence of 0.5 to 4.0 cases per 100 000 persons.

Observations

Erythrocytosis (hemoglobin >16.5 mg/dL in men or >16.0 mg/dL in women) is a required diagnostic criterion, although thrombocytosis (53%) and leukocytosis (49%) are common. Patients may have pruritus (33%), erythromelalgia (5.3%), transient visual changes (14%), and splenomegaly (36%) with abdominal discomfort. More than 95% of patients have a JAK2 gene variant, which helps distinguish PV from secondary causes of erythrocytosis, such as tobacco smoking or sleep apnea. Among 7 cohorts (1545 individuals), the median survival from diagnosis was 14.1 to 27.6 years. Prior to or at the time of PV diagnosis, arterial thrombosis occurred in 16% of patients and 7% had venous thrombotic events, which could involve unusual sites, such as splanchnic veins. PV is also associated with an increased bleeding risk, especially in patients with acquired von Willebrand disease, which can occur with extreme thrombocytosis (platelet count, ≥1000 × 109/L). All patients with PV should receive therapeutic phlebotomy (goal hematocrit, <45%) and low-dose aspirin (if no contraindications). Patients who are at higher risk of thrombosis include those aged 60 years or older or with a prior thrombosis. These patients and those with persistent PV symptoms may benefit from cytoreductive therapy with hydroxyurea or interferon to lower thrombosis risk and decrease symptoms. Ruxolitinib is a Janus kinase inhibitor that can alleviate pruritus and decrease splenomegaly in patients who are intolerant of or resistant to hydroxyurea. About 12.7% of patients with PV develop myelofibrosis and 6.8% develop acute myeloid leukemia.

Conclusions and Relevance

PV is a myeloproliferative neoplasm characterized by erythrocytosis and is almost universally associated with a JAK2 gene variant. PV is associated with an increased risk of arterial and venous thrombosis, hemorrhage, myelofibrosis, and acute myeloid leukemia. To decrease the risk of thrombosis, all patients with PV should be treated with aspirin and therapeutic phlebotomy to maintain a hematocrit of less than 45%. Cytoreductive therapies, such as hydroxyurea or interferon, are recommended for patients at high risk of thrombosis.

Ten years of experience with ruxolitinib since approval for polycythemia vera: A review of clinical efficacy and safety

The oral Janus kinase (JAK) 1/JAK2 inhibitor ruxolitinib was approved by the US Food and Drug Administration in 2014 for treatment of patients with polycythemia vera (PV) who have an inadequate response to or intolerance of hydroxyurea (HU). PV is a chronic myeloproliferative neoplasm defined by primary absolute erythrocytosis, bone marrow hypercellularity, and JAK mutations such as JAK2V617F. Patients with PV experience burdensome symptoms and are at risk of thromboembolic events, in particular those with resistance to or intolerance of initial treatments such as HU. Other risks for patients with PV include progression of disease to more aggressive forms with worse prognoses, such as myelofibrosis or blast-phase myeloproliferative neoplasms. This review summarizes the efficacy and safety of ruxolitinib from key phase 2 and 3 trials (MAJIC-PV, RESPONSE, RESPONSE-2, RELIEF, and Ruxo-BEAT), large real-world studies, and a decade of postmarketing surveillance safety data. The authors focus on improved blood count control, rates of thromboembolic events, symptom improvement, and markers of disease modification such as reduction of JAK2V617F allele burden in patients treated with ruxolitinib. They also discuss the well-characterized safety profile of ruxolitinib regarding hematologic and other adverse events of interest. In the 10 years since its approval, ruxolitinib remains a safe and effective standard-of-care treatment for PV. As the treatment landscape for PV continues to evolve in the coming years, the efficacy and safety profiles of ruxolitinib suggest it will remain a preferred treatment as monotherapy and as a potential backbone of future combination regimens.

Evolution of treatment strategies for solid tumors with RET rearrangement in China and real-world treatment status of Non-small Cell Lung Cancer (NSCLC)

OBJECTIVE

The present study endeavors to furnish an exhaustive review of the research advancements on solid tumors harboring RET rearrangement within the Chinese context, particularly emphasizing the examination of real-world therapeutic strategies and clinical outcomes observed in individuals diagnosed with advanced non-small cell lung cancer (NSCLC). The review delves into a critical assessment of the therapeutic efficacy of targeted RET inhibitors, while also scrutinizing the diverse array of treatment modalities employed in the Chinese patient population.

METHODS

The study conducted a comprehensive review of the advancements made by Chinese scholars in the realm of RET driver genes. It delved into the analysis of the incidence of RET rearrangements in solid tumors, alongside an examination of the varied treatment paradigms and their current status within China. Utilizing the RECIST 1.1 criteria, the study evaluated the therapeutic efficacy achieved in RET-positive NSCLC patients undergoing diverse treatment modalities. Furthermore, treatment-related adverse events (TRAEs) were meticulously graded following the Common Terminology Criteria for Adverse Events (CTCAE).

RESULTS

A retrospective, multi-center, real-world analysis was conducted, encompassing 64 patients diagnosed with pathologically confirmed RET rearrangement advanced non-small cell lung cancer (NSCLC) between December 2015 and November 2023. Notably, KIF5B-RET emerged as the most prevalent RET fusion partner, accounting for 59.4% of cases. Therapeutic interventions among these patients included specific targeted inhibitors such as Pralsetinib (48.4%), chemotherapy (34.3%), multi-target inhibitors (15.6%), and one case (1.6%) involving immunotherapy combined with anti-angiogenic therapy. In terms of progression-free survival (PFS), Pralsetinib monotherapy demonstrated a median PFS of 16.03 months, outperforming chemotherapy (2.87 months; p < 0.0001), chemotherapy combined with anti-angiogenic therapy (6.90 months; p = 0.048), and multi-target inhibitors (2.50 months; p < 0.0001). Furthermore, the one-year and two-year overall survival (OS) rates for Pralsetinib monotherapy were 64.3% and 46.4%, respectively. Regarding safety, 71.0% of patients receiving Pralsetinib experienced at least one adverse event, with 45.2% classified as grade 3-4 in severity. Notably, no fatalities were attributed to adverse events. Common adverse events included hemoglobin reduction (35.5%) and neutropenia (32.3%), indicative of an overall favorable safety profile for Pralsetinib in this patient population.

CONCLUSION

This study encapsulates the research endeavors and treatment advancements of RET rearrangement solid tumors within the Chinese healthcare landscape, specifically highlighting the diverse real-world therapeutic approaches and their effectiveness in managing advanced RET rearrangement NSCLC among Chinese patients. Notably, targeted RET inhibitors like Pralsetinib have emerged as potent therapeutic agents, exhibiting remarkable efficacy and a manageable safety profile in this patient cohort. These findings underscore the potential of Pralsetinib and similar targeted therapies as novel treatment options for individuals with RET fusion-positive NSCLC.

Time to Rethink Bronchiolitis Obliterans Syndrome Following Lung or Hematopoietic Cell Transplantation in Pediatric Patients

Background: Similar in histological characteristics and clinical manifestations, bronchiolitis obliterans syndrome (BOS) can develop following lung transplantation (LTx) or hematopoietic cell transplantation (HCT). In contrast to lung transplantation, where BOS is restricted to the lung allograft, HCT-related systemic graft-versus-host disease (GVHD) is the root cause of BOS. Because lung function declines following HCT, diagnosis becomes more difficult. Given the lack of proven effective medicines, treatment is based on empirical evidence. Methods: Cross-disciplinary learning is crucial, and novel therapies are under investigation to improve survival and avoid LTx. Recent advances have focused on updating the understanding of the etiology, clinical features, and pathobiology of BOS. It emphasizes the significance of learning from experts in other transplant modalities, promoting cross-disciplinary knowledge. Results: Our treatment algorithms are derived from extensive research and expert clinical input. It is important to ensure that immunosuppression is optimized and that any other conditions or contributing factors are addressed, if possible. Clear treatment algorithms are provided for each condition, drawing from the published literature and consensus clinical opinion. There are several novel therapies currently being investigated, such as aerosolized liposomal cyclosporine, Janus kinase inhibitors, antifibrotic therapies, and B-cell-directed therapies. Conclusions: We urgently need innovative treatments that can greatly increase survival rates and eliminate the need for LTx or re-transplantation.

Efficacy and safety of ruxolitinib vs best available therapy for polycythemia vera: An updated systematic review and meta-analysis

Ruxolitinib, a JAK1/JAK2 inhibitor, has been shown to have lower thromboembolism rates compared to placebo in polycythemia vera (PV) patients. This meta-analysis evaluates ruxolitinib's efficacy and safety against best available therapy (BAT) in patients with PV and in hydroxyurea-resistant/intolerant PV patients. A comprehensive literature search was conducted up to November 2023. We compared ruxolitinib and BAT for efficacy and safety endpoints. Six studies involving 1061 patients were analyzed, with 620 on BAT and 441 on ruxolitinib. Ruxolitinib showed higher hematocrit control (p = 0.015) and treatment response (p = 0.04) compared to BAT. It also significantly improved Myeloproliferative Neoplasms-Symptom Assessment Form scores (MPN-SAF) (p < 0.01). Additionally, patients with PV treated with ruxolitinib had higher rates of nonmelanoma skin cancer (p < 0.01). In subgroup analyses focusing on patients resistant or intolerant to hydroxyurea, ruxolitinib maintained its efficacy, significantly improving treatment response (p < 0.01) and significant improvements in MPN-SAF (p = 0.02) score when compared to BAT. The safety profile was consistent with the overall analyses, showing significantly reduced thromboembolism rates (p = 0.04), increased rates of anemia (p = 0.01), and increased herpes zoster infections (p = 0.02). Ruxolitinib outperforms BAT in PV and patients with PV-resistant or intolerant to hydroxyurea, offering better hematocrit control and reducing symptomatic burden and thromboembolism risk. Yet, it is associated with higher rates of anemia, herpes infection, and skin cancer.

Rational use of immunoglobulins (IVIgs and SCIgs) in secondary antibody deficiencies

Immunoglobulins for intravenous use (IVIgs) and subcutaneous use (SCIgs) can prevent recurrent and severe infections in patients with secondary antibody deficiencies that are frequently linked to haematological/oncological malignancies as well as other clinical conditions and their respective treatments. Even so, as IVIgs and SCIgs are costly and their supply is limited, their clinical use must be optimised. The aim of this position paper is to provide structured practical guidance on the optimal use of IVIgs and SCIgs in secondary antibody deficiencies, particularly in haematological and oncological practice. The authors agree that the occurrence of severe infections is a prerequisite for the use of IVIgs. Serum IgG levels in general as well as IgG subclass levels can be additional indicators of whether a patient could benefit from IVIgs. Responsiveness to vaccines can help to identify immunodeficiency. Patients with chronic lymphocytic leukaemia or multiple myeloma who are receiving respective treatment, especially B-cell depletion therapy, but also some patients with autoimmune diseases are prone to antibody deficiencies and need IVIgs. For the optimal use of IVIgs and to maximise their potential benefit, the indication must be individually assessed for each patient. As a primary treatment goal, the authors define a sufficient prophylaxis of severe infections, which can be supported by normalising IgG levels. If the initiated treatment is insufficient or linked to intolerable adverse reactions, switching the product within the class of IVIgs or changing to a different batch of the same product can be considered. Pausing treatment can also be considered if there are no infections, which happens more frequently in summer, but treatment needs to be resumed once infections return. These structured recommendations for IVIg treatment in patients with secondary antibody deficiency may provide guidance for clinical practice and therefore help to allocate IVIgs to those who will benefit the most, without overusing valuable resources.

Applications of Biological Therapy for Latent Infections: Benefits and Risks

Biological therapies have revolutionized medical treatment by targeting the key mediators or receptors involved in inflammatory responses, thereby effectively suppressing inflammation and achieving beneficial outcomes. They are more advanced than conventional therapies using corticosteroids and immunosuppressants, offering effective solutions for autoimmune diseases, cancer, transplant rejection, and various infectious diseases, including coronavirus disease 2019. Although they exert low immunosuppressive effects, biological therapies can reactivate specific biological targets associated with infections. This review summarizes the currently available biological therapies and discusses their immunosuppressive mechanisms and clinical applications, highlighting the variations in the types and frequencies of infection recurrence induced by different biological agents. Additionally, this review describes the risk factors associated with various biological agents, thus aiding clinicians in selecting the most appropriate biological therapy.

Unusual cause of dyspnea in patient with Myelofibrosis: The Ruxolitinib lung

Although pulmonary complications are frequent in patients suffering from hematological diseases, secondary pulmonary alveolar proteinosis is a very rare complication of myelofibrosis. We describe the case of a 65-year-old male patient treated by Ruxolitinib for myelofibrosis who developed a secondary pulmonary alveolar proteinosis complicated by a Mycobacterium avium infection. We believe that this respiratory complication might be related to the myelofibrosis and to the initiation of the Ruxolitinib according to its temporal relationship. Pulmonologists should be aware that respiratory symptoms in myelofibrosis patients taking Ruxolitinib may be related to pulmonary alveolar proteinosis.

FRACTION: protocol of a phase II study of Fedratinib and Nivolumab combination in patients with myelofibrosis and resistance or suboptimal response to JAK-inhibitor treatment of the German MPN study group (GSG-MPN)

Development of Janus-kinase (JAK) inhibitors has revolutionized the therapeutic landscape for patients with myeloproliferative neoplasia (MPN). Following approval of the first JAK1/2-inhibitor Ruxolitinib, symptoms of this inflammatory disease, characterized by splenomegaly, release of inflammatory cytokines and appearance of thrombosis, could be effectively reduced for the first time. However, JAK-inhibitor treatment is limited in several aspects: 1) duration of response: 3 years after initiation of therapy more than 50% of patients have discontinued JAK-inhibitor treatment due to lack of efficacy or resistance; 2) reduction of disease burden: while effective in reducing inflammation and constitutional symptoms, JAK-inhibitors fail to reduce the malignant clone in the majority of patients and therefore lack long-term efficacy. Early clinical trials for patients with myelofibrosis (MF) have tried to address these issues for patients with suboptimal response to Ruxolitinib therapy while combination therapies with Fedratinib are rare. Recent reports provided first evidence on how the JAK2-V617F mutated myeloid cells may influence T-cell responses. JAK2-V617F promoted the synthesis of PD-L1 in MPN cells leading to limited anti-neoplastic T-cell responses, metabolic changes in T-cells and eventually JAK2-V617F-driven immune-escape of MPN cells. These findings may facilitate the use of immunotherapeutic approaches for JAK-mutated clones. Immune checkpoints refer to a variety of inhibitory pathways that are crucial for maintaining self-tolerance and modulating the duration and amplitude of physiological immune responses in peripheral tissues in order to minimize collateral tissue damage. The FRACTION study is a single arm, open label Phase II trial investigating the combination of Fedratinib with the PD-1 inhibitor Nivolumab in patients with myelofibrosis and suboptimal or lack of response to JAK-inhibitor therapy. Over a 12 months period the trial assesses longer term outcomes, particularly the effects on clinical outcomes, such as induction of clinical remissions, quality of life and improvement of anemia. No prospective clinical trial data exist for combinations of JAK- and immune-checkpoint-inhibitors in the planned MF study population and this study will provide new findings that may contribute to advancing the treatment landscape for MF patients with suboptimal responses and limited alternatives.

Biologics Versus JAK Inhibitors. Part II: Risk of Infections. A Narrative Review

INTRODUCTION

The risk of infections associated with biological drugs (BD) and Janus kinase inhibitors (JAKi) has been extensively explored in the literature. However, there is a dearth of studies that evaluate both pharmacological groups together and, furthermore, compare them. Here, we review the risk of infections associated with BD and JAKi used in dermatology.

METHODS

A narrative review was performed. All relevant articles evaluating the risk of infection and opportunistic infections with BD and JAKi between January 2010 and February 2024 were selected.

RESULTS

Overall, the incidence of infections, serious infections, and opportunistic infections associated with BD and JAKi is low, but higher than in the general population. JAKi approved for dermatological disorders (abrocitinib, baricitinib, deucravacitinib, upadacitinib, ritlecitinib, and topical ruxolitinib) have been shown to be safe, and present a low rate of infections. We found an elevated risk, especially with anti-tumor necrosis factor (anti-TNF) agents, rituximab, and JAKi (particularly tofacitinib at high doses). Specific associations with infections include tuberculosis and tuberculosis reactivation with anti-TNF agents and tocilizumab; candidiasis with anti-interleukin (IL) 17 agents; hepatitis B virus reactivation with rituximab, anti-TNF, and JAKi; and herpes simplex and herpes zoster infections with JAKi (especially tofacitinib and upadacitinib at high doses). The incidence of infections with ustekinumab and anti-IL-23 was very low. Anti-IL-1, nemolizumab, tralokinumab, and omalizumab were not associated with an increased risk of infections. Dupilumab could decrease the incidence of cutaneous infections.

CONCLUSIONS

Anti-TNF agents, rituximab, and JAKi (particularly tofacitinib) can increase the risk of infections. Close monitoring of patients undergoing these therapies is recommended. Prospective studies with long-term follow-up are needed to comparatively evaluate the risks of infection deriving from treatment with BD and JAKi.

Overview of infectious complications among CAR T- cell therapy recipients

Chimeric antigen receptor-modified T cell (CAR T-cell) therapy has revolutionized the management of hematological malignancies. In addition to impressive malignancy-related outcomes, CAR T-cell therapy has significant toxicity-related adverse events, including cytokine release syndrome (CRS), immune effector cell associated neurotoxicity syndrome (ICANS), immune effector cell-associated hematotoxicity (ICAHT), and opportunistic infections. Different CAR T-cell targets have different epidemiology and risk factors for infection, and these targets result in different long-term immunodeficiency states due to their distinct on-target and off- tumor effects. These effects are exacerbated by the use of multimodal immunosuppression in the management of CRS and ICANS. The most effective course of action for managing infectious complications involves determining screening, prophylactic, and monitoring strategies and understanding the role of immunoglobulin replacement and re-vaccination strategies. This involves considering the nature of prior immunomodulating therapies, underlying malignancy, the CAR T-cell target, and the development and management of related adverse events. In conclusion, we now have an increasing understanding of infection management for CAR T-cell recipients. As additional effector cells and CAR T-cell targets become available, infection management strategies will continue to evolve.

TET2-STAT3-CXCL5 nexus promotes neutrophil lipid transfer to fuel lung adeno-to-squamous transition

Phenotypic plasticity is a rising cancer hallmark, and lung adeno-to-squamous transition (AST) triggered by LKB1 inactivation is significantly associated with drug resistance. Mechanistic insights into AST are urgently needed to identify therapeutic vulnerability in LKB1-deficient lung cancer. Here, we find that ten-eleven translocation (TET)-mediated DNA demethylation is elevated during AST in KrasLSL-G12D/+; Lkb1L/L (KL) mice, and knockout of individual Tet genes reveals that Tet2 is required for squamous transition. TET2 promotes neutrophil infiltration through STAT3-mediated CXCL5 expression. Targeting the STAT3-CXCL5 nexus effectively inhibits squamous transition through reducing neutrophil infiltration. Interestingly, tumor-infiltrating neutrophils are laden with triglycerides and can transfer the lipid to tumor cells to promote cell proliferation and squamous transition. Pharmacological inhibition of macropinocytosis dramatically inhibits neutrophil-to-cancer cell lipid transfer and blocks squamous transition. These data uncover an epigenetic mechanism orchestrating phenotypic plasticity through regulating immune microenvironment and metabolic communication, and identify therapeutic strategies to inhibit AST.

JAK inhibition enhances checkpoint blockade immunotherapy in patients with Hodgkin lymphoma

Unleashing antitumor T cell activity by checkpoint inhibitor immunotherapy is effective in cancer patients, but clinical responses are limited. Cytokine signaling through the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway correlates with checkpoint immunotherapy resistance. We report a phase I clinical trial of the JAK inhibitor ruxolitinib with anti-PD-1 antibody nivolumab in Hodgkin lymphoma patients relapsed or refractory following checkpoint inhibitor immunotherapy. The combination yielded a best overall response rate of 53% (10/19). Ruxolitinib significantly reduced neutrophil-to-lymphocyte ratios and percentages of myeloid suppressor cells but increased numbers of cytokine-producing T cells. Ruxolitinib rescued the function of exhausted T cells and enhanced the efficacy of immune checkpoint blockade in preclinical solid tumor and lymphoma models. This synergy was characterized by a switch from suppressive to immunostimulatory myeloid cells, which enhanced T cell division.

Second line extracorporeal photopheresis for cortico-resistant acute and chronic GVHD after allogeneic hematopoietic cell transplantation for hematological malignancies: Long-term results from a real-life study

BACKGROUND & OBJECTIVES

The primary objective of this observational study was to perform an exhaustive description concerning patients receiving extracorporeal photopheresis (ECP) as second line treatment after steroid resistance for either acute or chronic GVHD following allo-HCT, secondary objectives were to evaluate the efficacy and long-term outcomes.

STUDY DESIGN

A total of 106 patients were included, 65 (61%) males and 41 (39%) females with a median age at transplantation of 52 years (range: 20-67). ECP was initiated after transplantation either for acute GVHD [N = 25 (24%), 12 grade III and 13 grade IV] affecting skin alone (N = 5), gut alone (N = 12), gut and liver (N = 8), or chronic GVHD [N = 81 (76%), 15 (14%) limited and 66 (62%) extensive].

RESULTS

Among the 25 patients treated for acute GHVD, 67% were responders and among the 81 patients with chronic GVHD, 78% were responders. Patients with acute GVHD had a median OS of 6 months with a survival probability at 2 years of 35% [95%CI: 14-56]. Patients with chronic GVHD had a median OS of 72 months with a survival probability at 2 years of 68% [95%CI: 56-78]. There was a significant difference in terms of survival for patients responding to ECP compared to non-responders in both acute and chronic GVHD forms. Acute GVHD grade III-IV, negatively impacted on OS (HR=7.77, 95%CI: 1.7-34), p = 0.007 and on disease relapse HR= 5.88, 95%CI: 1.7-20, p = 0.005.

CONCLUSION

We demonstrated that ECP is an effective treatment for GVHD in a good proportion of patients with high overall response rate.

Ruxolitinib for the treatment of acute and chronic graft-versus-host disease in children: a systematic review and individual patient data meta-analysis

Steroid-refractory graft-versus-host disease (SR-GvHD) represents a major complication of pediatric allogenic hematopoietic stem cell transplantation. Ruxolitinib, a selective JAK 1-2 inhibitor, showed promising results in the treatment of SR-GvHD in adult trial, including patients >12 years old. This systematic review aims to evaluate ruxolitinib use for SR-GvHD in the pediatric population. Among the 12 studies included, ruxolitinib administration presented slight differences. Overall response rate (ORR) ranged from 45% to 100% in both acute and chronic GvHD. Complete response rates (CR) varied from 9% to 67% and from 0% to 28% in aGvHD and cGvHD, respectively. Individual-patient meta-analysis from 108 children under 12 years showed an ORR and CR for aGvHD of 74% and 56%, respectively, while in cGvHD ORR was 78% but with only 11% achieving CR. Treatment-related toxicities were observed in 20% of patients, including cytopenia, liver toxicity, and infections. Age, weight, graft source, previous lines of therapy, and dose did not significantly predict response, while a higher rate of toxicities was observed in aGvHD patients. In conclusion, ruxolitinib shows promising results in the treatment of SR-GvHD in children, including those under 12 years. Specific pediatric perspective trials are currently ongoing to definitely assess its efficacy and safety.

Updates on efficacy and safety janus kinase inhibitors in juvenile dermatomyositis

INTRODUCTION

Juvenile dermatomyositis (JDM) is a rare autoimmune disease most commonly with proximal weakness due to inflammation and characteristic skin rashes. Most patients have a chronic or polycyclic disease course on standard therapy so better treatments are needed. An interferon signature is well-established in key tissues of JDM. Janus kinase inhibitors (jakinibs), which can decrease IFN signaling, are therefore appealing as a targeted therapy.

AREAS COVERED

Herein is a review of the growing literature on JDM patients in jakinibs, including specifics of their jakinib exposure, summary of efficacy, disease features, and characteristics of patients treated, and safety parameters.

EXPERT OPINION

The vast majority of refractory JDM patients respond to jakinib therapy, though they have varied features, doses, and previous/concurrent medications, and data is largely retrospective. Jakinibs are an exciting and promising treatment in JDM. Evaluation with larger prospective controlled studies is needed to answer remaining questions about jakinibs in JDM regarding dosing, which JDM patients to treat with jakinibs, potential biomarkers to use, and how best to monitor safety risks in JDM.

Managing infectious challenges in the age of molecular-targeted therapies for adult hematological malignancies

Over the last decade, the therapeutic landscape for hematological malignancies (HMs) has witnessed a remarkable surge in the development of novel biological and small-molecule-targeted immunomodulatory agents. These therapies have drastically improved survival, but some come at the cost of increased risk of bacterial, viral, and/or fungal infections and on-target off-tumor immunological side effects. To mitigate such risks, physicians must be well informed about infectious complications and necessary preventive measures, such as screening, vaccinations, and antimicrobial prophylaxis. Furthermore, physicians should be vigilant about the noninfectious side effects of these agents that can mimic infections and understand their potential drug-drug interactions with antimicrobials. Strengthening and harmonizing the current surveillance and reporting system for drug-associated infections in real-world settings is essential to better ascertain the potential infections associated with these agents. In this review, we aimed to summarize the infection risks associated with novel agents used for specific HMs and outline recommended strategies for monitoring and prophylaxis.

Update of the guidelines for the pharmacological treatment of rheumatoid arthritis by the Mexican College of Rheumatology 2023

OBJECTIVE

To develop updated guidelines for the pharmacological management of rheumatoid arthritis (RA).

METHODS

A group of experts representative of different geographical regions and various medical services catering to the Mexican population with RA was formed. Questions based on Population, Intervention, Comparison, and Outcome (PICO) were developed, deemed clinically relevant. These questions were answered based on the results of a recent systematic literature review (SLR), and the evidence's validity was assessed using the GRADE system, considered a standard for these purposes. Subsequently, the expert group reached consensus on the direction and strength of recommendations through a multi-stage voting process.

RESULTS

The updated guidelines for RA treatment stratify various therapeutic options, including different classes of DMARDs (conventional, biologicals, and JAK inhibitors), as well as NSAIDs, glucocorticoids, and analgesics. By consensus, it establishes the use of these in different subpopulations of interest among RA patients and addresses aspects related to vaccination, COVID-19, surgery, pregnancy and lactation, and others.

CONCLUSIONS

This update of the Mexican guidelines for the pharmacological treatment of RA provides reference points for evidence-based decision-making, recommending patient participation in joint decision-making to achieve the greatest benefit for our patients. It also establishes recommendations for managing a variety of relevant conditions affecting our patients.

Upadacitinib-Induced Hepatitis B Reactivation Leading to Liver Transplant

Hepatitis B virus (HBV) reactivation can occur with the use of immunosuppressive therapy used to treat autoimmune conditions, such as rheumatoid arthritis. Janus kinase inhibitors, such as upadacitinib, have been approved for the treatment of rheumatoid arthritis. This is the first case report of a patient who used upadacitinib without antiviral prophylaxis against HBV and developed HBV reactivation, leading to fulminant hepatic failure necessitating emergent liver transplantation.

Disseminated Histoplasmosis in a Patient with Myelofibrosis on Ruxolitinib: A Case Report and Review of the Literature on Ruxolitinib-Associated Invasive Fungal Infections

Ruxolitinib, a selective inhibitor of Janus kinases, is a standard treatment for intermediate/high-risk myelofibrosis (MF) but is associated with a predisposition to opportunistic infections, especially herpes zoster. However, the incidence and characteristics of invasive fungal infections (IFIs) in these patients remain uncertain. In this report, we present the case of a 59-year-old woman with MF who developed disseminated histoplasmosis after seven months of ruxolitinib use. The patient clinically improved after ten weeks of combined amphotericin B and azole therapy, and ruxolitinib was discontinued. Later, the patient received fedratinib, a relatively JAK2-selective inhibitor, without relapse of histoplasmosis. We also reviewed the literature on published cases of proven IFIs in patients with MF who received ruxolitinib. Including ours, we identified 28 such cases, most commonly due to Cryptococcus species (46%). IFIs were most commonly disseminated (39%), followed by localized lung (21%) infections. Although uncommon, a high index of suspicion for opportunistic IFIs is needed in patients receiving JAK inhibitors. Furthermore, the paucity of data regarding the optimal management of IFIs in patients treated with JAK inhibitors underscore the need for well-designed studies to evaluate the epidemiology, pathobiology, early diagnosis, and multimodal therapy of IFIs in patients with hematological malignancies receiving targeted therapies.

Serious infections in patients with VEXAS syndrome: data from the French VEXAS registry

INTRODUCTION

Vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome is an acquired autoinflammatory monogenic disease with a poor prognosis whose determinants are not well understood. We aimed to describe serious infectious complications and their potential risk factors.

METHODS

Retrospective multicentre study including patients with VEXAS syndrome from the French VEXAS Registry. Episodes of serious infections were described, and their risk factors were analysed using multivariable Cox proportional hazards models.

RESULTS

Seventy-four patients with 133 serious infections were included. The most common sites of infection were lung (59%), skin (10%) and urinary tract (9%). Microbiological confirmation was obtained in 76%: 52% bacterial, 30% viral, 15% fungal and 3% mycobacterial. Among the pulmonary infections, the main pathogens were SARS-CoV-2 (28%), Legionella pneumophila (21%) and Pneumocystis jirovecii (19%). Sixteen per cent of severe infections occurred without any immunosuppressive treatment and with a daily glucocorticoid dose ≤10 mg. In multivariate analysis, age >75 years (HR (95% CI) 1.81 (1.02 to 3.24)), p.Met41Val mutation (2.29 (1.10 to 5.10)) and arthralgia (2.14 (1.18 to 3.52)) were associated with the risk of serious infections. JAK inhibitors were most associated with serious infections (3.84 (1.89 to 7.81)) compared with biologics and azacitidine. After a median follow-up of 4.4 (2.5-7.7) years, 27 (36%) patients died, including 15 (56%) due to serious infections.

CONCLUSION

VEXAS syndrome is associated with a high incidence of serious infections, especially in older patients carrying the p.Met41Val mutation and treated with JAK inhibitors. The high frequency of atypical infections, especially in patients without treatment, may indicate an intrinsic immunodeficiency.

JAK Inhibitors in Cytokine Storm Syndromes

Cytokine storm syndromes (CSSs) comprise a group of severe and often fatal hyperinflammatory conditions driven by the overproduction of pro-inflammatory cytokines by activated cells of the immune system. Many of the CSS-associated cytokines mediate their downstream effects by signaling through the Janus kinases (JAKs) and signal transducers and activators of transcription (STATs). In addition, several of these cytokines are produced downstream of JAK/STAT pathway activation. Therefore, targeting JAK/STAT signaling using small molecule JAK inhibitors has become an increasingly appealing therapeutic option to dampen hyperinflammation in patients with CSSs. Application of JAK inhibitors in preclinical CSS models has shown improvements in multiple sequelae of hyperinflammation, and there is growing clinical evidence supporting the efficacy of JAK inhibition in patients with these conditions. Although generally well tolerated, JAK inhibitor use is not without potential for toxicity, especially in settings like CSSs where end-organ dysfunction is common. More prospective clinical trials incorporating JAK inhibitors, alone or in combination with other immunomodulatory therapies, are necessary to determine the optimal dosing, schedule, efficacy, and tolerability of these agents for patients experiencing CSSs.

ACVR1: A Novel Therapeutic Target to Treat Anemia in Myelofibrosis

Activin receptor type I (ACVR1) is a transmembrane kinase receptor belonging to bone morphogenic protein receptors (BMPs). ACVR1 plays an important role in hematopoiesis and anemia via the BMP6/ACVR1/SMAD pathway, which regulates expression of hepcidin, the master regulator of iron homeostasis. Elevated hepcidin levels are inversely associated with plasma iron levels, and chronic hepcidin expression leads to iron-restricted anemia. Anemia is one of the hallmarks of myelofibrosis (MF), a bone marrow (BM) malignancy characterized by BM scarring resulting in impaired hematopoiesis, splenomegaly, and systemic symptoms. Anemia and red blood cell transfusions negatively impact MF prognosis. Among the approved JAK inhibitors (ruxolitinib, fedratinib, momelotinib, and pacritinib) for MF, momelotinib and pacritinib are preferably used in cytopenic patients; both agents are potent ACVR1 inhibitors that suppress hepcidin expression via the BMP6/ACVR1/SMAD pathway and restore iron homeostasis/erythropoiesis. In September 2023, momelotinib was approved as a treatment for patients with MF and anemia. Zilurgisertib (ACVR1 inhibitor) and DISC-0974 (anti-hemojuvelin monoclonal antibody) are evaluated in early phase clinical trials in patients with MF and anemia. Luspatercept (ACVR2B ligand trap) is assessed in transfusion-dependent MF patients in a registrational phase 3 trial. Approved ACVR1 inhibitors and novel agents in development are poised to improve the outcomes of anemic MF patients.

Polycythemia Vera: Barriers to and Strategies for Optimal Management

Polycythemia vera (PV) is a subtype of myeloproliferative neoplasms characterized by impaired quality of life and severe complications. Despite the increasingly in-depth knowledge of this condition, it necessitates a multifaceted management approach to mitigate symptoms and prevent thrombotic and hemorrhagic events, ensuring prolonged survival. The therapeutic landscape has been revolutionized in recent years, where venesection and hydroxycarbamide associated with antiplatelet therapy have a central role and are now accompanied by other drugs, such as interferon and Janus kinase inhibitors. Ongoing research and advancements in targeted therapies hold promise for further enhancing the therapeutic choice for PV management.

Integrated Stress Response (ISR) Pathway: Unraveling Its Role in Cellular Senescence

Cellular senescence is a complex process characterized by irreversible cell cycle arrest. Senescent cells accumulate with age, promoting disease development, yet the absence of specific markers hampers the development of selective anti-senescence drugs. The integrated stress response (ISR), an evolutionarily highly conserved signaling network activated in response to stress, globally downregulates protein translation while initiating the translation of specific protein sets including transcription factors. We propose that ISR signaling plays a central role in controlling senescence, given that senescence is considered a form of cellular stress. Exploring the intricate relationship between the ISR pathway and cellular senescence, we emphasize its potential as a regulatory mechanism in senescence and cellular metabolism. The ISR emerges as a master regulator of cellular metabolism during stress, activating autophagy and the mitochondrial unfolded protein response, crucial for maintaining mitochondrial quality and efficiency. Our review comprehensively examines ISR molecular mechanisms, focusing on ATF4-interacting partners, ISR modulators, and their impact on senescence-related conditions. By shedding light on the intricate relationship between ISR and cellular senescence, we aim to inspire future research directions and advance the development of targeted anti-senescence therapies based on ISR modulation.

Understanding and treatment of cutaneous graft-versus-host-disease

The skin is the outermost mechanical barrier where dynamic immune reactions take place and is the most commonly affected site in both acute and chronic graft-versus-host disease (GVHD). If not properly treated, pain and pruritis resulting from cutaneous GVHD can increase the risk of secondary infection due to erosions, ulcerations, and damage of underlying tissues. Furthermore, resulting disfiguration can cause distress and significantly impact patients' quality of life. Thus, a deeper understanding of skin-specific findings of GVHD is needed. This review will highlight some promising results of recent pre-clinical studies on the pathophysiology of skin GVHD and summarize the diagnostic and staging/grading procedures according to the clinical manifestations of skin GVHD. In addition, we will summarize outcomes of various GVHD treatments, including skin-specific response rates.

Management of classical Philadelphia chromosome-negative myeloproliferative neoplasms in Asia: consensus of the Asian Myeloid Working Group

Myeloproliferative neoplasms (MPN) are a heterogeneous group of clonal hematopoietic stem cell disorders characterized clinically by the proliferation of one or more hematopoietic lineage(s). The classical Philadelphia-chromosome (Ph)-negative MPNs include polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). The Asian Myeloid Working Group (AMWG) comprises representatives from fifteen Asian centers experienced in the management of MPN. This consensus from the AMWG aims to review the current evidence in the risk stratification and treatment of Ph-negative MPN, to identify management gaps for future improvement, and to offer pragmatic approaches for treatment commensurate with different levels of resources, drug availabilities and reimbursement policies in its constituent regions. The management of MPN should be patient-specific and based on accurate diagnostic and prognostic tools. In patients with PV, ET and early/prefibrotic PMF, symptoms and risk stratification will guide the need for early cytoreduction. In younger patients requiring cytoreduction and in those experiencing resistance or intolerance to hydroxyurea, recombinant interferon-α preparations (pegylated interferon-α 2A or ropeginterferon-α 2b) should be considered. In myelofibrosis, continuous risk assessment and symptom burden assessment are essential in guiding treatment selection. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) in MF should always be based on accurate risk stratification for disease-risk and post-HSCT outcome. Management of classical Ph-negative MPN entails accurate diagnosis, cytogenetic and molecular evaluation, risk stratification, and treatment strategies that are outcome-oriented (curative, disease modification, improvement of quality-of-life).

Risk of hepatitis B reactivation in patients with myeloproliferative neoplasms treated with ruxolitinib

Classical Philadelphia-negative myeloproliferative neoplasms (MPNs), i.e., polycythemia vera, essential thrombocythemia, and primary/secondary myelofibrosis, are clonal disorders of the hematopoietic stem cell in which an uncontrolled proliferation of terminally differentiated myeloid cells occurs. MPNs are characterized by mutations in driver genes, the JAK2V617F point mutation being the most commonly detected genetic alteration in these hematological malignancies. Thus, JAK inhibition has emerged as a potential therapeutic strategy in MPNs, with ruxolitinib being the first JAK inhibitor developed, approved, and prescribed in the management of these blood cancers. However, the use of ruxolitinib has been associated with a potential risk of infection, including opportunistic infections and reactivation of hepatitis B. Here, we briefly describe the association between ruxolitinib treatment in MPNs and hepatitis B reactivation.

Current therapies for classic myeloproliferative neoplasms: A focus on pathophysiology and supportive care

PURPOSE

This article concisely evaluates current therapies that have received regulatory approval for the treatment of classic myeloproliferative neoplasms (MPNs). Pertinent pathophysiology and supportive care are discussed. Emerging therapies are also briefly described.

SUMMARY

MPNs are a heterogeneous group of diseases characterized by acquired abnormalities of hematopoietic stem cells (HSCs), resulting in the generation of transformed myeloid progenitor cells that overproduce mature and immature cells within the myeloid lineage. Mutations in JAK2 and other driver oncogenes are central to the genetic variability of these diseases. Cytoreductive therapies such as hydroxyurea, anagrelide, interferon, and therapeutic phlebotomy aim to lower the risk of thrombotic events without exposing patients to an increased risk of leukemic transformation. However, no comparisons can be made between these therapies, as reduction of thrombotic risk has not been used as an endpoint. On the other hand, Janus kinase (JAK) inhibitors such as ruxolitinib, fedratinib, pacritinib, and momelotinib (an investigational agent at the time of writing) directly target the constitutively activated JAK-signal transducer and activator of transcription (JAK-STAT) pathway of HSCs in the bone marrow. Mutations of genes in the JAK-STAT signaling pathway provide a unifying understanding of MPNs, spur therapeutic innovations, and represent opportunities for pharmacists to optimize mitigation strategies for both disease-related and treatment-related adverse effects.

CONCLUSION

Treatment options for MPNs span a wide range of disease mechanisms. The growth of targeted therapies holds promise for expanding the treatment arsenal for these rare, yet complex diseases and creates opportunities to optimize supportive care for affected patients.

Alopecia Areata: Current Treatments and New Directions

Alopecia areata is an autoimmune hair loss disease that is non-scarring and is characterized by chronic inflammation at the hair follicle level. Clinically, patients' presentation varies from patchy, circumscribed scalp involvement to total body and scalp hair loss. Current management is guided by the degree of scalp and body involvement, with topical and intralesional steroid injections as primarily first-line for mild cases and broad immunosuppressants as the mainstay for more severe cases. Until recently, the limited number of blinded, randomized, placebo-controlled clinical trials for this disease had made establishing an evidence-based treatment paradigm challenging. However, growing insights into the pathogenesis of alopecia areata through blood and tissue analysis of human lesions have identified several promising targets for therapy. T-helper (Th) 1/interferon skewing has traditionally been described as the driver of disease; however, recent investigations suggest activation of additional immune mediators, including the Th2 pathway, interleukin (IL)-9, IL-23, and IL-32, as contributors to alopecia areata pathogenesis. The landscape of alopecia areata treatment has the potential to be transformed, as several novel targeted drugs are currently undergoing clinical trials. Given the recent US FDA approval of baricitinib and ritlecitinib, Janus kinase (JAK) inhibitors are a promising drug class for treating severe alopecia areata cases. This article will review the efficacy, safety, and tolerability of current treatments for alopecia areata, and will provide an overview of the emerging therapies that are leading the revolution in the management of this challenging disease.

Role of interleukin 6 and its soluble receptor on the diffusion barrier dysfunction of alveolar tissue

During respiratory infection, barrier dysfunction in alveolar tissue can result from "cytokine storm" caused by overly reactive immune response. Particularly, interleukin 6 (IL-6) is implicated as a key biomarker of cytokine storm responsible for and further progression to pulmonary edema. In this study, alveolar-like tissue was reconstructed in a microfluidic device with: (1) human microvascular lung endothelial cells (HULEC-5a) cultured under flow-induced shear stress and (2) human epithelial cells (Calu-3) cultured at air-liquid interface. The effects of IL-6 and the soluble form of its receptor (sIL-6R) on the permeability, electrical resistance, and morphology of the endothelial and epithelial layers were evaluated. The diffusion barrier properties of both the endothelial and epithelial layers were significantly degraded only when IL-6 treatment was combined with sIL-6R. As suggested by recent review and clinical studies, our results provide unequivocal evidence that the barrier dysfunction occurs through trans-signaling in which IL-6 and sIL-6R form a complex and then bind to the surface of endothelial and epithelial cells, but not by classical signaling in which IL-6 binds to membrane-expressed IL-6 receptor. This finding suggests that the role of both IL-6 and sIL-6R should be considered as important biomarkers in developing strategies for treating cytokine storm.

AIPSS-MF machine learning prognostic score validation in a cohort of myelofibrosis patients treated with ruxolitinib

BACKGROUND

In myelofibrosis (MF), new model scores are continuously proposed to improve the ability to better identify patients with the worst outcomes. In this context, the Artificial Intelligence Prognostic Scoring System for Myelofibrosis (AIPSS-MF), and the Response to Ruxolitinib after 6 months (RR6) during the ruxolitinib (RUX) treatment, could play a pivotal role in stratifying these patients.

AIMS

We aimed to validate AIPSS-MF in patients with MF who started RUX treatment, compared to the standard prognostic scores at the diagnosis and the RR6 scores after 6 months of treatment.

METHODS AND RESULTS

At diagnosis, the AIPSS-MF performs better than the widely used IPSS for primary myelofibrosis (C-index 0.636 vs. 0.596) and MYSEC-PM for secondary (C-index 0.616 vs. 0.593). During RUX treatment, we confirmed the leading role of RR6 in predicting an inadequate response by these patients to JAKi therapy compared to AIPSS-MF (0.682 vs. 0.571).

CONCLUSION

The new AIPSS-MF prognostic score confirms that it can adequately stratify this subgroup of patients already at diagnosis better than standard models, laying the foundations for new prognostic models developed tailored to the patient based on artificial intelligence.

EBV-Gastritis Preceded the Development of Nasopharyngeal EBV (+) Diffuse Large B Cell Lymphoma in a Patient With Ruxolitinib-Induced Immunosuppression

Epstein-Barr virus (EBV) is acquired early in life as asymptomatic or symptomatic infectious mononucleosis (IM) and remains latent in a few B cells in most individuals. Pathologic EBV-reactivation affects immunosuppressed individuals and manifests as IM-like syndromes, polyclonal lymphoproliferative disorders, EBV-related lymphomas, and carcinomas. EBV-associated gastritis is an underrecognized and very rarely reported entity. We report a case of a 65-year-old woman with ruxolitinib-treated polycythemia vera, who developed EBV viremia and EBV gastritis. The patient improved after the ruxolitinib dose reduction and administration of antiviral therapy. A few months after discontinuation of the antiviral therapy the gastric symptoms recurred, numerous gastric ulcers were identified, and a nasopharyngeal mass was detected. A biopsy of the nasopharynx showed an EBV (+) diffuse large B cell lymphoma. Ruxolitinib was discontinued and the patient was started on rituximab monotherapy with a resolution of symptoms and pathologic improvement. Our case supports earlier reports of an association of ruxolitinib therapy with EBV complications. An early diagnosis of EBV gastritis in immunocompromised patients is important since the gastric infection may precede or co-exist with a developing EBV-associated malignancy. Our case and existing literature suggest that EBV gastritis in symptomatic patients with iatrogenic immunosuppression requires discontinuation of immunosuppressive therapy if feasible, treatment with antivirals, and close surveillance for possible evolving/concurrent EBV (+) malignancy.

A Journey Through JAK Inhibitors for the Treatment of Myeloproliferative Diseases

PURPOSE OF REVIEW

Chronic myeloproliferative neoplasms (MPN) represent a group of diseases characterised by constitutive activation of the JAK/STAT pathway in a clonal myeloid precursor. The therapeutic approach aims to treat the symptom burden (headache, itching, debilitation), splenomegaly, slow down the fibrotic proliferation in the bone marrow and reduce the risk of thrombosis/bleeding whilst avoiding leukaemic transformation.

RECENT FINDINGS

In recent years, the advent of JAK inhibitors (JAKi) has significantly broadened treatment options for these patients. In myelofibrosis, symptom control and splenomegaly reduction can improve quality of life with improved overall survival, not impacting progression into acute leukaemia. Several JAKi are available and used worldwide, and combination approaches are now being explored. In this chapter, we review the approved JAKi, highlighting its strengths, exploring potential guidelines in choosing which one to use and reasoning towards future perspectives, where the combinations of therapies seem to promise the best results.

The role of IFN-γ-signalling in response to immune checkpoint blockade therapy

Treatment with immune checkpoint inhibitors, widely known as immune checkpoint blockade therapy (ICBT), is now the fourth pillar in cancer treatment, offering the chance of durable remission for patients with advanced disease. However, ICBT fails to induce objective responses in most cancer patients with still others progressing after an initial response. It is necessary, therefore, to elucidate the primary and acquired resistance mechanisms to ICBT to improve its efficacy. Here, we highlight the paradoxical role of the cytokine interferon-γ (IFN-γ) in ICBT response: on the one hand induction of IFN-γ signalling in the tumour microenvironment correlates with good ICBT response as it drives the cellular immune responses required for tumour destruction; nonetheless, IFN-γ signalling is implicated in ICBT acquired resistance. We address the negative feedback and immunoregulatory effects of IFN-γ signalling that promote immune evasion and resistance to ICBT and discuss how these can be targeted pharmacologically to restore sensitivity or circumvent resistance.

Next-Generation JAK2 Inhibitors for the Treatment of Myeloproliferative Neoplasms: Lessons from Structure-Based Drug Discovery Approaches

Selective inhibitors of Janus kinase (JAK) 2 have been in demand since the discovery of the JAK2 V617F mutation present in patients with myeloproliferative neoplasms (MPN); however, the structural basis of V617F oncogenicity has only recently been elucidated. New structural studies reveal a role for other JAK2 domains, beyond the kinase domain, that contribute to pathogenic signaling. Here we evaluate the structure-based approaches that led to recently-approved type I JAK2 inhibitors (fedratinib and pacritinib), as well as type II (BBT594 and CHZ868) and pseudokinase inhibitors under development (JNJ7706621). With full-length JAK homodimeric structures now available, superior selective and mutation-specific JAK2 inhibitors are foreseeable.

SIGNIFICANCE

The JAK inhibitors currently used for the treatment of MPNs are effective for symptom management but not for disease eradication, primarily because they are not strongly selective for the mutant clone. The rise of computational and structure-based drug discovery approaches together with the knowledge of full-length JAK dimer complexes provides a unique opportunity to develop better targeted therapies for a range of conditions driven by pathologic JAK2 signaling.

The pharmacotherapeutic management of patients with myelofibrosis: looking beyond JAK inhibitors

INTRODUCTION

The approach to myelofibrosis (MF) has been revolutionized in recent years, overcoming the traditional therapies, often not very effective. Janus kinase inhibitors (JAKi - from ruxolitinib up to momelotinib) were the first class of drugs with considerable results.

AREAS COVERED

Ongoing, new molecules are being tested that promise to give hope even to those patients not eligible for bone marrow transplants who become intolerant or are refractory to JAKi, for which therapeutic hopes are currently limited. Telomerase, murine double minute 2 (MDM2), phosphatidylinositol 3-kinase δ (PI3Kδ), BCL-2/xL, and bromodomain and extra-terminal motif (BET) inhibitors are the drugs with promising results in clinical trials and close to closure with consequent placing on the market, finally allowing JAK to look beyond. The novelty of the MF field was searched in the PubMed database, and the recently completed/ongoing trials are extrapolated from the ClinicalTrial website.

EXPERT OPINION

From this point of view, the use of new molecules widely described in this review, probably in association with JAKi, will represent the future treatment of choice in MF, leaving, in any case, the potential new approaches actually in an early stage of development, such as the use of immunotherapy in targeting CALR, which is coming soon.

Recent progress of JAK inhibitors for hematological disorders

JAK inhibitors are important therapeutic options for hematological disorders, especially myeloproliferative neoplasms. Ruxolitinib, the first JAK inhibitor approved for clinical use, improves splenomegaly and ameliorates constitutional symptoms in both myelofibrosis and polycythemia vera patients. Ruxolitinib is also useful for controlling hematocrit levels in polycythemia vera patients who were inadequately controlled by conventional therapies. Furthermore, pretransplantation use of ruxolitinib may improve the outcome of allo-hematopoietic stem cell transplantation in myelofibrosis. In contrast to these clinical merits, evidence of the disease-modifying action of ruxolitinib, i.e., reduction of malignant clones or improvement of bone marrow pathological findings, is limited, and many myelofibrosis patients discontinued ruxolitinib due to adverse events or disease progression. To overcome these limitations of ruxolitinib, several new types of JAK inhibitors have been developed. Among them, fedratinib was proven to provide clinical merits even in patients who were resistant or intolerant to ruxolitinib. Pacritinib and momelotinib have shown merits for myelofibrosis patients with thrombocytopenia or anemia, respectively. In addition to treatment for myeloproliferative neoplasms, recent studies have demonstrated that JAK inhibitors are novel and attractive therapeutic options for corticosteroid-refractory acute as well as chronic graft versus host disease.

Current application status and structure-activity relationship of selective and non-selective JAK inhibitors in diseases

JAK kinase includes four family members: JAK1, JAK2, JAK3, and TYK2. It forms the JAK-STAT pathway with signal transmitters and activators of subscription (STAT). This pathway is one of the main mechanisms by which many cytokine receptors transduce intracellular signals, it is associated with the occurrence of various immune, inflammatory, and tumor diseases. JAK inhibitors block the signal transduction of the JAK-STAT pathway by targeting JAK kinase. Based on whether they target multiple subtypes of JAK kinase, JAK inhibitors are categorized into pan-JAK inhibitors and selective JAK inhibitors. Compared with pan JAK inhibitors, selective JAK inhibitors are associated with a specific member, thus more targeted in therapy, with improved efficacy and reduced side effects. Currently, a number of JAK inhibitors have been approval for disease treatment. This review summarized the current application status of JAK inhibitors that have been marketed, advances of JAK inhibitors currently in phase Ш clinical trials, and the structure-activity relationship of them, with an intention to provide references for the development of novel JAK inhibitors.

Momelotinib long-term safety and survival in myelofibrosis: integrated analysis of phase 3 randomized controlled trials

Momelotinib is the first inhibitor of Janus kinase 1 (JAK1) and JAK2 shown to also inhibit activin A receptor type 1 (ACVR1), a key regulator of iron homeostasis, and has demonstrated improvements in splenomegaly, constitutional symptoms, and anemia in myelofibrosis (MF). This long-term analysis pooled data from 3 randomized phase 3 studies of momelotinib (MOMENTUM, SIMPLIFY-1, and SIMPLIFY-2), representing MF disease from early (JAK inhibitor-naive) to late (JAK inhibitor-experienced) stages. Patients in the control arms (danazol in MOMENTUM, ruxolitinib in SIMPLIFY-1, and best available therapy in SIMPLIFY-2) could cross over to receive momelotinib at the end of the 24-week randomized period, and all patients could continue momelotinib treatment after the completion of these studies via an extended access protocol (XAP). Across these studies, 725 patients with MF received momelotinib; 12% remained on therapy for ≥5 years, with a median treatment exposure of 11.3 months (range, 0.1-90.4 months). The most common nonhematologic treatment-emergent adverse event (AE) occurring in ≥20% of patients was diarrhea (any grade, 27% and grade ≥3, 3%). Any-grade thrombocytopenia, anemia, and neutropenia occurred in 25%, 23%, and 7% of patients, respectively. The most common reason for momelotinib discontinuation was thrombocytopenia (4% discontinuation rate). The incidence of AEs of clinical importance (eg, infections, malignant transformation, peripheral neuropathy, and hemorrhage) did not increase over time. This analysis of one of the largest randomized trial databases for a JAK inhibitor to date in MF demonstrated a consistent safety profile of momelotinib without long-term or cumulative toxicity. These trials were registered at www.clinicaltrials.gov as: MOMENTUM (#NCT04173494), SIMPLIFY-1 (#NCT01969838), SIMPLIFY-2 (#NCT02101268), and XAP (#NCT03441113).

Vaccinations in hematological patients in the era of target therapies: Lesson learnt from SARS-CoV-2

Novel targeting agents for hematologic diseases often exert on- or off-target immunomodulatory effects, possibly impacting on response to anti-SARS-CoV-2 vaccinations and other vaccines. Agents that primarily affect B cells, particularly anti-CD20 monoclonal antibodies (MoAbs), Bruton tyrosine kinase inhibitors, and anti-CD19 chimeric antigen T-cells, have the strongest impact on seroconversion. JAK2, BCL-2 inhibitors and hypomethylating agents may hamper immunity but show a less prominent effect on humoral response to vaccines. Conversely, vaccine efficacy seems not impaired by anti-myeloma agents such as proteasome inhibitors and immunomodulatory agents, although lower seroconversion rates are observed with anti-CD38 and anti-BCMA MoAbs. Complement inhibitors for complement-mediated hematologic diseases and immunosuppressants used in aplastic anemia do not generally affect seroconversion rate, but the extent of the immune response is reduced under steroids or anti-thymocyte globulin. Vaccination is recommended prior to treatment or as far as possible from anti-CD20 MoAb (at least 6 months). No clearcut indications for interrupting continuous treatment emerged, and booster doses significantly improved seroconversion. Cellular immune response appeared preserved in several settings.

A review of prophylactic regimens to prevent invasive fungal infections in hematology patients undergoing chemotherapy or stem cell transplantation

INTRODUCTION

The recent introduction of targeted therapies, including monoclonal antibodies, tyrosine-kinase inhibitors, and immunotherapies has improved the cure rate of hematologic patients. The implication of personalized treatment on primary antifungal prophylaxis will be discussed.

AREAS COVERED

We reviewed the literature for clinical trials reporting the rate of invasive fungal infections during targeted and cellular therapies and stem cell transplant, and the most recent international guidelines for primary antifungal prophylaxis.

EXPERT OPINION

As the use of personalized therapies is growing, the risk of invasive fungal infection has emerged in various clinical settings. Therefore, it is possible that the use of mold-active antifungal prophylaxis would spread in the next years and the risk of breakthrough infections would increase. The introduction of new antifungal agents in the clinical armamentarium is expected to reduce clinical unmet needs concerning the management of primary antifungal prophylaxis and improve outcome of patients.

An unusual presentation of Pseudomonas citronellolis bacteraemia and Campylobacter gastroenteritis infection in a human - a case report and literature review

Introduction

Pseudomonas citronellolis is an unusual pathogen in humans and has not been extensively described in the scientific literature. Herein, we present a case of bacteremia and septic shock due to Pseudomonas citronellolis following Campylobacter species gastroenteritis in a patient with immunosuppression.

Case Presentation

An 80-year-old man with myeloproliferative disorder on ruxolitinib presented with several days of worsening abdominal pain, which rapidly developed into septic shock with multi-organ failure and explosive diarrhea. Gram-negative bacilli observed on Gram staining of his blood culture broth were later identified as Pseudomonas citronellolis and Bacteroides thetaiotaomicron . Repeated abdominal imaging revealed no evidence of intestinal perforation or megacolon. In addition, stool PCR was positive for Campylobacter species. His clinical course improved after 14 days of meropenem with complete resolution of his symptoms and organ failure.

Conclusion

P. citronellolis is a rare infection in humans. We postulate that Janus Associated Kinase (JAK) inhibition in myeloproliferative disorders heightened this patient's risk of bacterial translocation and severe illness in the setting of Campylobacter gastroenteritis. P. citronellolis may be identified more frequently as a pathogen in humans as more advanced diagnostic technologies become increasingly available in clinical microbiology.

Ruxolitinib Treatment During Myelofibrosis Leads to Cutaneous Mycobacterium marinum Infection: A Case Report

Mycobacterium marinum is an atypical bacterium, and skin infections caused by it are relatively rare, usually occurring in workers engaged in seafood processing and housewives who clean and prepare fish for consumption. The infection often occurs after the skin is punctured by fish scales, spines, etc. The JAK/STAT signaling pathway is closely related to the human immune response to infections. Therefore, JAK inhibitors may induce and exacerbate various infections in clinical practice. This article reports a case of mycobacterium marinum skin infection in the left upper limb of a female patient with chronic idiopathic myelofibrosis during treatment with ruxolitinib. The patient denied being punctured or scratched by fish scales or spines. Clinical manifestations included multiple infiltrative erythemas and subcutaneous nodules in the thumb and forearm. Histopathological examination showed infiltration of mixed acute and chronic inflammatory cells in the subcutaneous tissue. The diagnosis was ultimately confirmed by NGS sequencing. The patient was cured after taking moxifloxacin and clarithromycin for 10 months. Infection is a common adverse reaction of JAK inhibitors, but no literature has reported on mycobacterium marinum skin infections occurring during JAK inhibitor treatment, which is relatively rare. As the clinical application of JAK inhibitors becomes more widespread, the skin infections they cause may present in various forms and require the attention of clinicians.

Risk of Infections Secondary to the Use of Targeted Therapies in Hematological Malignancies

Concurrent infections in hematological malignancies (HM) are major contributors to adverse clinical outcomes, including prolonged hospitalization and reduced life expectancy. Individuals diagnosed with HM are particularly susceptible to infectious pathogens due to immunosuppression, which can either be inherent to the hematological disorder or induced by specific therapeutic strategies. Over the years, the treatment paradigm for HM has witnessed a tremendous shift, from broad-spectrum treatment approaches to more specific targeted therapies. At present, the therapeutic landscape of HM is constantly evolving due to the advent of novel targeted therapies and the enhanced utilization of these agents for treatment purposes. By initiating unique molecular pathways, these agents hinder the proliferation of malignant cells, consequently affecting innate and adaptive immunity, which increases the risk of infectious complications. Due to the complexity of novel targeted therapies and their associated risks of infection, it often becomes a daunting task for physicians to maintain updated knowledge in their clinical practice. The situation is further aggravated by the fact that most of the initial clinical trials on targeted therapies provide inadequate information to determine the associated risk of infection. In such a scenario, a cumulative body of evidence is paramount in guiding clinicians regarding the infectious complications that can arise following targeted therapies. In this review, I summarize the recent knowledge on infectious complications arising in the context of targeted therapies for HM.