A first-in-class inhibitor of HSP110 to potentiate XPO1-targeted therapy in primary mediastinal B-cell lymphoma and classical Hodgkin lymphoma.

BACKGROUND: Primary mediastinal B-cell lymphoma (PMBL) and classical Hodgkin lymphoma (cHL) are distinct hematological malignancies of B-cell origin that share many biological, molecular, and clinical characteristics. In particular, the JAK/STAT signaling pathway is a driver of tumor development due to multiple recurrent mutations, particularly in STAT6. Furthermore, the XPO1 gene that encodes exportin 1 (XPO1) shows a frequent point mutation (E571K) resulting in an altered export of hundreds of cargo proteins, which may impact the success of future therapies in PMBL and cHL. Therefore, targeted therapies have been envisioned for these signaling pathways and mutations. METHODS: To identify novel molecular targets that could overcome the treatment resistance that occurs in PMBL and cHL patients, we have explored the efficacy of a first-in-class HSP110 inhibitor (iHSP110-33) alone and in combination with selinexor, a XPO1 specific inhibitor, both in vitro and in vivo. RESULTS: We show that iHSP110-33 decreased the survival of several PMBL and cHL cell lines and the size of tumor xenografts. We demonstrate that HSP110 is a cargo of XPO1wt as well as of XPO1E571K. Using immunoprecipitation, proximity ligation, thermophoresis and kinase assays, we showed that HSP110 directly interacts with STAT6 and favors its phosphorylation. The combination of iHSP110-33 and selinexor induces a synergistic reduction of STAT6 phosphorylation and of lymphoma cell growth in vitro and in vivo. In biopsies from PMBL patients, we show a correlation between HSP110 and STAT6 phosphorylation levels. CONCLUSIONS: These findings suggest that HSP110 could be proposed as a novel target in PMBL and cHL therapy.

Haploidentical hematopoietic stem cell transplantation as a first-line treatment for paediatric severe aplastic anemia: a single-center research.

MRD-HSCT is the first-line therapy for children with SAA, while it is not easy to find a compatible donor due to the Chinese one-child policy. IST has a high recurrence rate, a risk of clonal transformation. Thus, Haplo-HSCT, as a first-line treatment, has gradually attracted clinicians' attention. To evaluate the efficacy of Haplo-HSCT in children with SAA, we performed a retrospective study (2006.06-2021.01) of 210 patients with AA who received HSCT or IST in Beijing Children's Hospital. The OS and FFS rates were analyzed to evaluate the efficacy of Haplo-HSCT and IST. We found that from 2006 to 2021, 3- and 5-year cumulative survival rates were both 85.3% in the first-line Haplo group, 98.1% and 96.8% in the first-line IST group, both 85.7% in the ATG group (P = 0.866), both 100% in the ATG + TPO group (P = 0.016), and 99.1% and 97.2% in the ATG + eltrombopag group (P = 0.056). 3- and 5-year cumulative FFS rates were both 85.3% in the first-line Haplo-HSCT group and 67.5% and 66.2% in the first-line IST group (P = 0.033). Therefore, we believe that Haplo-HSCT can be a first-line treatment for paediatric SAA.

[Efficacy and safety of eltrombopag in the treatment of primary immune thrombocytopenia: real-world data from a single medical center].

Objective: This study aimed at investigating the efficacy and safety of eltrombopag in the treatment of adult primary immune thrombocytopenia (ITP) and evaluated the factors influencing its efficacy and side effects. Methods: A total of 198 patients with adult ITP who were admitted to Tianjin Medical University General Hospital between January 2018 and March 2022 were retrospectively analyzed. The efficacy of each starting dose of eltrombopag was evaluated, and adverse events were analyzed. The factors influencing efficacy were investigated, including sex, age, adult ITP type, platelet antibodies, and combined drug treatments. Results: Of the 198 patients, 70 males and 128 females with a median age of 45 years (18-88 years) were included; 130 (65.7%) had newly diagnosed adult ITP, 25 (12.6%) had persistent adult ITP, and 43 (21.7%) had chronic adult ITP. The bleeding event scores at baseline were assessed; 84.3% had scores of<4 and 15.7% had scores of ≥4. The eltrombopag response rate (initial response) at 6 weeks was 78.8% (complete response [CR]: 49.0%; CR1: 14.6%; CR2: 15.2%). The median response time to eltrombopag was 7 (7, 14) days. The initial response rates to 25, 50, and 75 mg eltrombopag were 74.1%, 85.9%, and 60.0%, respectively (P=0.031). The initial response rate to the 50 mg dose was significantly higher than that of the 25-mg and 75-mg doses. Two patients received 100 mg as the starting dose, and their initial response was 0. Regarding dose adjustment, 70.7% of the patients remained on the starting dose, 8.6% underwent dose adjustment to 50 mg, and 6.1% underwent dose adjustment to 75 mg. Another two patients underwent dose adjustment to 100 mg. After dose adjustment, the persistent response rates were 83.6%, 85.3%, and 85.7% for the 25-, 50-, and 75-mg doses, respectively, with no significant difference. After dose adjustment, the sustained efficacy rate for the 100-mg dose (4 patients) was 100.0%. After 6 weeks of treatment with eltrombopag, the overall bleeding score of patients with ITP decreased. The number of patients with a score of ≥4 decreased to 0, the number of patients with a score of<4 decreased, and there was no significant change in the number of patients with a score of 1-2. The most common adverse event associated with eltrombopag was impaired liver function (7.7%). No thrombosis events or other adverse events were observed. ITP type and number of megakaryocytes significantly affected the initial response to eltrombopag. The initial response rates to eltrombopag for newly diagnosed adult ITP, persistent adult ITP, and chronic adult ITP were 85.3%, 56.0%, and 76.2%, respectively (P=0.003). For megakaryocytes, the initial response rates were 61.8%, 87.1%, and 84.3% (P=0.009) for the decreased, normal, and increased megakaryocyte groups, respectively. Conclusion: Eltrombopag, as a second-line or higher treatment for adult ITP, has a rapid onset of action and good safety. The initial response rate is significantly higher with a dose of 50 mg than with a dose of 25 mg. Patients with newly diagnosed ITP and those with normal or increased megakaryocyte numbers have a higher initial response rate to eltrombopag.

Eltrombopag can promote platelet implantation after allogeneic hematopoietic stem cell transplantation as safely and similarly to thrombopoietin.

Background: Eltrombopag has demonstrated efficacy in treating low platelet (PLT) levels, but it remains unclear whether eltrombopag can promote PLT engraftment after hematopoietic stem cell transplantation (HSCT). Methods: Forty-one HSCT patients received eltrombopag 50 mg/d from +1 day until PLT >50 × 109/L or 1 month after HSCT. Fifty-one patients in the same period received thrombopoietin (TPO) to promote PLT graft after HSCT and served as a control group. Results: A total of 51 patients who applied TPO during the same period were treated as a control. In the eltrombopag group, the median time to white blood cells (WBC) graft was 12 days (range, 10-17 days) and the PLT graft was 15 days (range, 10-30 days), whereas for the patients in the TPO group, the median time to WBC and PLT graft was 12 days (range, 9-23 days) and 15.5 days (range, 9-41 days), respectively. In the first month after HSCT, the median WBC count in the eltrombopag group was 4.41 × 109/L (range, 0.87-40.01 × 109/L) and the median PLT was 89x109/L (range, 30-401 × 109/L); the median WBC and PLT \counts in the TPO group were 4.65 × 109/L (range, 0.99-23.63 × 109/L) and 86 × 109/L (range, 5-512 × 109/L), respectively. Patients in the TPO or eltrombopag group did not experience serious side effects after drug administration, and the difference in side effects on liver and kidney function between the two groups was not statistically significant. Conclusion: Eltrombopag is safe and similarly promotes platelet engraftment to thrombopoietin after allogeneic HSCT.

XPO1 blockade with KPT-330 promotes apoptosis in cutaneous T-cell lymphoma by activating the p53-p21 and p27 pathways.

Dysregulated nuclear-cytoplasmic trafficking has been shown to play a role in oncogenesis in several types of solid tumors and hematological malignancies. Exportin 1 (XPO1) is responsible for the nuclear export of several proteins and RNA species, mainly tumor suppressors. KPT-330, a small molecule inhibitor of XPO1, is approved for treating relapsed multiple myeloma and diffuse large B-cell lymphoma. Cutaneous T-cell lymphoma (CTCL) is an extranodal non-Hodgkin lymphoma with an adverse prognosis and limited treatment options in advanced stages. The effect of therapeutically targeting XPO1 with KPT-330 in CTCL has not been established. We report that XPO1 expression is upregulated in CTCL cells. KPT-330 reduces cell proliferation, induces G1 cell cycle arrest and apoptosis. RNA-sequencing was used to explore the underlying mechanisms. Genes associated with the cell cycle and the p53 pathway were significantly enriched with KPT-330 treatment. KPT-330 suppressed XPO1 expression, upregulated p53, p21WAF1/Cip1, and p27Kip1 and their nuclear localization, and downregulated anti-apoptotic protein (Survivin). The in vivo efficacy of KPT-330 was investigated using a bioluminescent xenograft mouse model of CTCL. KPT-330 blocked tumor growth and prolonged survival (p < 0.0002) compared to controls. These findings support investigating the use of KPT-330 and next-generation XPO1 inhibitors in CTCL.

Herombopag for the treatment of persistent thrombocytopenia following hematopoietic stem cell transplantation.

Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) stands as a pivotal treatment for hematologic malignancies, often considered the sole effective treatment option. A frequent complication following allo-HSCT is poor graft function (PGF), with one of its primary manifestations being persistent thrombocytopenia (PT), comprising prolonged isolated thrombocytopenia (PIT) and secondary failure of platelet recovery (SFPR). Conventional treatment methods have had poor efficacy and a high transplantation-associated mortality rate. In recent years, the efficacy of eltrombopag has been reported in the treatment of post-transplantation PT, and additional thrombopoietin receptor agonists (TPO-RA) have been developed. Herombopag is a next-generation TPO-RA which has strong proliferation-promoting effects on human TPO-R-expressing cells (32D-MPL) and hematopoietic progenitor cells in vitro. We reviewed eighteen patients with transplantation-associated thrombocytopenia who received herombopag when eltrombopag was ineffective or poorly tolerated and evaluated its efficacy including effects on survival. Herombopag was administered at a median time of 197 days post-transplantation. Six patients achieved complete response (CR), with a median time to CR of 56 days. Five patients achieved partial response (PR), and the median time to PR was 43 days. Seven patients were considered to have no response (NR). The overall response (OR) rate was 61.1%, and the cumulative incidence (CI) of OR was 90.2%. No patients developed herombopag-associated grade 3-4 toxicity. The median follow-up period was 6.5 months. Twelve patients survived and six patients died, with an overall survival rate of 66.7%. This is the first study to demonstrate the efficacy and safety of herombopag in transplantation-associated thrombocytopenia after failing eltrombopag, introducing a new approach in the treatment of PT following allo-HSCT.

Treatment of refractory/relapsed Diamond-Blackfan anaemia with eltrombopag.

Diamond-Blackfan anaemia (DBA) is a rare, inherited bone marrow failure syndrome with a ribosomal defect causing slowed globin chain production with normal haem synthesis, causing an overabundance of reactive iron/haem and erythroid-specific cellular toxicity. Eltrombopag, a non-peptide thrombopoietin receptor agonist, is a potent intracellular iron chelator and induced a robust durable response in an RPS19-mutated DBA patient on another trial. We hypothesized eltrombopag would improve RBC production in DBA patients. We conducted a single-centre, single-arm pilot study (NCT04269889) assessing safety and erythroid response of 6 months of daily, fixed-dose eltrombopag for DBA patients. Fifteen transfusion-dependent (every 3-5 weeks) patients (median age 18 [range 2-56]) were treated. One responder had sustained haemoglobin improvement and >50% reduction in RBC transfusion frequency. Of note, 7/15 (41%) patients required dose reductions or sustained discontinuation of eltrombopag due to asymptomatic thrombocytosis. Despite the low response rate, eltrombopag has now improved erythropoiesis in several patients with DBA with a favourable safety profile. Dosing restrictions due to thrombocytosis may cause insufficient iron chelation to decrease haem production and improve anaemia in most patients. Future work will focus on erythropoiesis dynamics in patients and use of haem synthesis inhibitors without an impact on other haematopoietic lineages.

Understanding complex disease-related mechanisms: Rational therapies for Diamond-Blackfan anaemia.

The rich history surrounding Diamond-Blackfan anaemia (DBA), originally described in 1938 as congenital hypoplastic anaemia2 reflects the evolution of paediatric haematology. In their paper, the authors1 present the results of a clinical trial using the thrombopoietin-mimetic agent eltrombopag to treat red cell failure in DBA. A low response rate belies the importance of this work. Commentary on: Duncan et al. Treatment of refractory/relapsed Diamond-Blackfan anaemia with eltrombopag. Br J Haematol 2024;204:2077-2085.

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.

Selinexor for the treatment of patients with relapsed or refractory multiple myeloma.

OBJECTIVE: Multiple myeloma cells resist standard therapies due to overexpression of the transport protein, exportin 1. Selinexor is a novel drug that targets the Exportin 1 protein in these cells. DATA SOURCE: A comprehensive search was done, and data showing the efficacy and safety of selinexor in relapsed/refractory multiple myeloma was collected using PubMed, Google Scholar, and clincialtrials.gov. DATA SUMMARY: Results from the clinical trials STORM, BOSTON, and STOMP were included. Parts I and II of the STORM trial revealed a progression-free survival (PFS) of 4.7 and 3.7 months, a median duration of response of 6.2 and 4.4 months, and an overall survival of 7.3 and 8.4 months, respectively. BOSTON trial's SVd arm (selinexor, bortezomib, and dexamethasone) had a median follow-up period of 13.2 months and an mPFS of 13.93 months. The Vd arm (bortezomib and dexamethasone) had a median follow-up duration of 16.5 months and an mPFS of 9.46 months. The STOMP trial is still active and has limited data available. The SKd arm (selinexor, carfilzomib, and dexamethasone) reported an overall response rate of 66.7% in patients with triple refractory multiple myeloma, and 82% in patients with high-risk cytogenetics. The SPd arm (selinexor, pomalidomide, and dexamethasone) shows an overall response rate of 54.30% in pomalidomide naïve-nonrefractory, 35.70% in pomalidomide refractory and 60% in those dosed at RP2D. SRd arm (selinexor, lenalidomide, and dexamethasone) shows an overall response rate of 91.7% in lenalidomide naïve and 12.5% in lenalidomide refractory patients. SVd (selinexor, bortezomib, and dexamethasone) arm reported an overall response rate of 63% in all patients while the SDd arm (selinexor, daratumumab, and dexamethasone) showed an overall response rate of 73%. CONCLUSION: To improve the outcome of patients with relapsed/refractory multiple myeloma, it is critical to develop new therapies, assess potential therapeutic synergies, and overcome drug resistance by determining the efficacy of multiple myeloma therapies across multiple disease subgroups.

Eltrombopag treatment in thrombocytopenia following hematopoietic stem cell transplantation: A multicenter real-world experience.

INTRODUCTION: Thrombocytopenia is among the most common complications following hematopoietic stem cell transplantation and is associated with increased mortality and morbidity with no standard treatment yet. In this multicenter and retrospective study, we aim to present our multi-center experience of Eltrombopag treatment in patients with isolated thrombocytopenia following HSCT. MATERIAL-METHOD: A total of 73 patients from 5 centers who underwent autologous or allogeneic stem cell transplantation, had no primary disease relapse, all of whom had neutrophil engraftment, complete chimerism, and who were diagnosed with Prolonged Isolated Thrombocytopenia (PIT) or Secondary Failure Of Platelet Recovery (SFPR) were included in the study. The patients were initiated on Eltrombopag at a dose of 50-150 mg. Complete response was defined as a platelet count >50×109/L for 7 consecutive days with no transfusion support. RESULTS: A total of 50.3% of the patients underwent Autologous and 49.7% Allogeneic Stem Cell Transplantation, 54.8% were diagnosed with PIT, and 45.2% were diagnosed with SFPR, and the treatment with 50-150 mg/day Eltrombopag was initiated on the median day +42. Complete response was achieved in 71.2% of these patients on the median day 23 of the treatment. No significant effects of the initial dose (50-150 mg/day) were detected in the Complete Response in the multivariate analysis on response. An insufficient number of Megakaryocytes in the bone marrow before Eltrombopag treatment was determined as an independent risk factor in determining the response (OR 3.57, 95% CI 1.21-10.55). The overall survival of the patients who did not respond to Eltrombopag was found to be significantly worse than that of patients who responded (p=0.022, HR:2.74, 95% CI 1.12-6.54). CONCLUSION: As a result of the present study, Eltrombopag treatment was found to be effective and safe in thrombocytopenia that develops following hematopoietic stem cell transplantation. It was concluded that its use may be more effective in patients with sufficient bone marrow megakaryocytes before the treatment and an initial dose of 50 mg/day may be appropriate in terms of cost, effectiveness, and toxicity. Large-scale randomized and controlled prospective studies are needed to determine the roles of Eltrombopag treatment in patients with post-transplant PIT and SFPR.

Treatment patterns and outcomes among adults with immune thrombocytopenia receiving pharmaceutical second-line therapies: a retrospective cohort study using administrative claims data.

OBJECTIVES: To describe and compare real-world treatment patterns and clinical outcomes among individuals with immune thrombocytopenia (ITP) receiving second-line therapies (rituximab, romiplostim, or eltrombopag). METHODS: A retrospective cohort study was conducted using a large administrative claims database (January 2013-May 2020) among continuously enrolled patients ≥18 years prescribed second-line ITP therapies. The index date was the date of the first claim of the study medications. Treatment patterns and outcomes were measured during the 12-month follow-up period. Inverse probability of treatment weighting (IPTW) was used to balance covariates across treatment groups. Multivariable logistic regression was used to compare treatment patterns and bleeding risk outcomes. RESULTS: A total of 695 patients were included (rituximab, N = 285; romiplostim, N = 212; eltrombopag, N = 198). After IPTW, all baseline covariates were balanced. Compared to eltrombopag, patients in the rituximab cohort were 57% more likely to receive other ITP therapies (systematic corticosteroids or third-line therapies) during the follow-up period (odds ratio [OR] = 1.571, p = .030). There was no significant difference in the odds of receiving a different second-line therapy or experiencing a bleeding-related episode among three groups (p > .050). Patients in the romiplostim cohort were 69% more likely to receive rescue therapy compared to those in the rituximab cohort (OR = 1.688, p = .025). CONCLUSION: Patients with ITP receiving rituximab were more likely to need other ITP therapies but did not experience higher risk of bleeding compared to those receiving eltrombopag or romiplostim. Benefits, risks, cost-effectiveness, and patient preference should all be considered in optimizing second-line therapy for ITP.

The problem of immune thrombocytopenia refractory to both eltrombopag and romiplostim.

Immune thrombocytopenia refractory to multiple thrombopoietin receptor agonists remains a challenging clinical problem. This commentary discusses and contextualizes the recent report on this entity from Moulis and colleagues, and how to move forward with these patients. Commentary on: Moulis et al. Difficult-to-treat primary immune thrombocytopenia in adults: Prevalence and burden. Results from the CARMEN-France Registry. Br J Haematol 2024;204:1476-1482.

Anamorelin Induced Acute Hyperglycemia in a Patient with Advanced Pancreatic Cancer and Diabetes: A Case Report.

Anamorelin (ANAM) is a novel ghrelin receptor agonist for the treatment of cancer cachexia. In clinical trials of ANAM, glucose metabolism disorders as adverse effects were relatively frequent, however, when and how they occur remains unclear. Moreover, the safety in patients with pancreatic cancer and/or diabetes has not been clarified because most previous studies focused on patients with non-small cell lung cancer and had excluded patients with poorly controlled diabetes. Herein, a 66-year-old man with advanced pancreatic cancer and diabetes was administered ANAM, and acute hyperglycemia was developed and could be monitored by the self-monitoring of blood glucose (SMBG). Increasing the insulin dose failed to control hyperglycemia adequately, but the hyperglycemia ameliorated quickly after ANAM discontinuation. The continuous glucose monitoring (CGM) revealed that the sensor glucose levels had remained in the high range throughout the day during ANAM administration despite using 1.5 times more insulin. Our report is one of the few that describe the details of ANAM-induced hyperglycemia and provides important information for the safe and effective use of ANAM.

Dual Inhibition of CDK4/6 and XPO1 Induces Senescence With Acquired Vulnerability to CRBN-Based PROTAC Drugs.

BACKGROUND & AIMS: Despite the increasing number of treatment options available for liver cancer, only a small proportion of patients achieve long-term clinical benefits. Here, we aim to develop new therapeutic approaches for liver cancer. METHODS: A compound screen was conducted to identify inhibitors that could synergistically induce senescence when combined with cyclin-dependent kinase (CDK) 4/6 inhibitor. The combination effects of CDK4/6 inhibitor and exportin 1 (XPO1) inhibitor on cellular senescence were investigated in a panel of human liver cancer cell lines and multiple liver cancer models. A senolytic drug screen was performed to identify drugs that selectively killed senescent liver cancer cells. RESULTS: The combination of CDK4/6 inhibitor and XPO1 inhibitor synergistically induces senescence of liver cancer cells in vitro and in vivo. The XPO1 inhibitor acts by causing accumulation of RB1 in the nucleus, leading to decreased E2F signaling and promoting senescence induction by the CDK4/6 inhibitor. Through a senolytic drug screen, cereblon (CRBN)-based proteolysis targeting chimera (PROTAC) ARV-825 was identified as an agent that can selectively kill senescent liver cancer cells. Up-regulation of CRBN was a vulnerability of senescent liver cancer cells, making them sensitive to CRBN-based PROTAC drugs. Mechanistically, we find that ubiquitin specific peptidase 2 (USP2) directly interacts with CRBN, leading to the deubiquitination and stabilization of CRBN in senescent liver cancer cells. CONCLUSIONS: Our study demonstrates a striking synergy in senescence induction of liver cancer cells through the combination of CDK4/6 inhibitor and XPO1 inhibitor. These findings also shed light on the molecular processes underlying the vulnerability of senescent liver cancer cells to CRBN-based PROTAC therapy.

Impact of a Best Practices Program in Patients with Relapsed/Refractory Multiple Myeloma Receiving Selinexor.

Best practice (BP) in cancer care consists of a multifaceted approach comprising individualized treatment plans, evidence-based medicine, the optimal use of supportive care and patient education. We investigated the impact of a BP program in patients with relapsed/refractory multiple myeloma (RRMM) receiving selinexor. Features of the BP program that were specific to selinexor were initiating selinexor at doses ≤80 mg once weekly and the upfront use of standardized antiemetics. Study endpoints included time to treatment failure (TTF), duration of therapy, dose limiting toxicities and overall survival. Comparative analysis on TTF and duration of therapy was conducted using a log-rank test and multivariate Cox proportional hazard regression. Over the ensuing 12-month post-BP period, 41 patients received selinexor-based therapy compared to 68 patients who received selinexor-based therapy pre-BP implementation. Patients treated in the post-BP period had reductions in TTF (hazard ratio [HR] = 0.50; 95% CI: 0.27 to 0.92). Patients in the pre-BP period were four times more likely to stop therapy than those in the post-period (odds ratio [OR] = 4.0, 95% CI: 1.75 to 9.3). The findings suggest a BP program tailored to selinexor could increase the time to treatment failure, increase treatment duration and lower the incidence of drug limiting toxicities.

Face validity of the Kids' ITP Tools (KIT) in the era of thrombopoietin receptor agonists.

The Kids' ITP Tools (KIT) is a questionnaire to assess quality of life of children with immune thrombocytopenia (ITP). The aim of this study was to update this previously validated tool to align with changes in clinical practice, specifically, treatment with thrombopoietin receptor agonists (TPO-RAs). Children aged 1-18 with ITP and/or their families were recruited to participate in interviews to review the KIT. Twenty-six interviews were conducted. Based on interview data from children and families, current guidelines, and expert opinion, five changes were made to the KIT in order to improve its face validity.

Long-term eltrombopag in children with chronic immune thrombocytopenia: A single-centre extended real-life observational study in China.

We have previously confirmed the efficacy and safety of eltrombopag (ELT) in children with chronic immune thrombocytopenia (cITP). However, data on both long-term exposure and early use of TPO-RAs are lacking, so further 'field-practice' evidence on treatment is required. Here, we report the long-term follow-up results (between September 2018 and June 2023) of our previous study. The main objective of this study was to retrospectively review our large institutional experience with ITP patients previously enrolled in our paediatric cITP study. We had more than 3 years of follow-up by June 2023 for treatment patterns and outcomes. A total of 65 patients (28 males) were enrolled, with a median age at ELT initiation of 6.34 (range 1.65, 14.13) years and a follow-up of 47.07 (36.00, 57.00) months, with 40.36 (10.53, 56.83) months of ELT therapy at the time of analysis. In total, 29.23% (19/65) of patients discontinued ELT due to stable response, and 18.46% (12/65) of patients switched to other ITP therapies due to loss of response (LOR) after 19.13 (14.53, 26.37) months. Of the 19 patients who discontinued ELT due to a stable response, 24.62% (16/65) achieved a 12 m sustained response off-treatment (SRoT); the last recorded platelet count ranged from 56 to 166 × 109 /L (median 107 × 109/L); and 4.62% (3/65) patients relapsed at 5, 6 and 9 months after discontinuation. Of the 12 patients who LOR to ELT after 19.13 (14.53, 26.37) months of therapy, four switched to avatrombopag, three switched to hetrombopag, two switched to traditional Chinese medicine (TCM), one underwent splenectomy and two received additional prednisolone under ELT treatment. Thirty-four patients who tapered and maintained a durable response. The patients with LOR and the patients with tapering were compared; the platelet count at the start of ELT is lower, and the time to response is longer in the patients with LOR. The platelet count at the start of ELT and the time to response may be the predictive factors for LOR during ELT treatment. We report more than 3 years of long-term clinical data on children with cITP using ELT. These data do not raise any new safety concerns regarding the long-term use of ELT in children with cITP.

XPO1-Mediated mRNA Export of Genome Maintenance Regulators Drives Chemotherapy Resistance in Aggressive Lymphoma.

Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoid malignancy and displays vast genetic and transcriptomic heterogeneity. Current treatment guidelines recommend first-line chemoimmunotherapy consisting of an anthracycline backbone, which produces cure rates of approximately 65%. However, the remaining patients will face relapsed or refractory disease, which, even in the era of chimeric antigen receptor T cells, is difficult to treat. In this issue of Cancer Research, Marullo and colleagues investigate the biological underpinnings of the tumor-suppressive activity of the newly approved XPO1 inhibitor selinexor in the treatment of lymphoma. In a translational effort covering genomic and biochemical approaches, combined with in vivo validation experiments and a phase I clinical trial, they demonstrate that upon DNA damage, XPO1 selectively exports transcripts encoding proteins involved in genome maintenance via the RNA-binding proteins THOC4 and eIF4E. Pharmacologic interception of this export process enhances chemosensitivity in various lymphoma models, and combined selinexor plus chemoimmunotherapy displays a favorable toxicity profile and early evidence of efficacy in patients. See related article by Marullo et al., p. 101.