International Journal of Hematology最新文献

Ropeginterferon alfa-2b (ropegIFN), a new-generation interferon-based agent, has been approved in Japan for patients with polycythemia vera (PV) who are ineligible for or respond inadequately to conventional treatment. However, long-term outcomes with ropegIFN in Japanese patients have not been reported. This extension of a phase 2 study of ropegIFN in Japanese patients with PV aimed to determine its long-term safety/efficacy, and changes over time in JAK2 V617F allele burden. Here, we report data from the phase 2 study and subsequent extension over a period of 36 months. The primary endpoint was the complete hematologic response (CHR) maintenance rate without phlebotomy (hematocrit value < 45% without phlebotomy during the previous 12 weeks, platelet count ≤ 400 × 10⁹/L, and white blood cell count ≤ 10 × 10⁹/L). The CHR maintenance rates were 8/27 (29.6%), 18/27 (66.7%), and 22/27 (81.5%) at 12, 24, and 36 months, respectively. No thrombotic or hemorrhagic events occurred. The median allele burden change from baseline was - 74.8% at 36 months. All patients experienced adverse events; 25/27 (92.6%) experienced adverse drug reactions (ADRs), but no serious ADRs or deaths occurred. This interim analysis demonstrated the safety and efficacy of ropegIFN over 36 months in Japanese patients with PV.

Ruxolitinib, a Janus kinase (JAK1-JAK2) inhibitor, has demonstrated safety and efficacy in patients with graft-versus-host disease (GvHD). This phase 3 randomized trial (REACH3) evaluated the efficacy and the safety of ruxolitinib 10 mg twice daily compared with investigator-selected best available therapy (BAT) in a subgroup of Japanese patients (n = 37) with steroid-refractory or dependent (SR/D) chronic GvHD. At data cut-off, treatment was ongoing in 17 patients and discontinued in 20. The overall response rate (complete or partial) at week 24 was greater with ruxolitinib than BAT (50% vs. 20%; odds ratio, 4.13 [95% CI, 0.90-18.9]). The best overall response rate (complete or partial response at any time point up to week 24) was higher with ruxolitinib than BAT (68.2% vs. 46.7%; odds ratio, 2.69 [95% CI, 0.66-10.9]). Ruxolitinib led to longer median failure-free survival than BAT (18.6 months vs. 3.7 months; hazard ratio, 0.34; [95% CI, 0.14-0.85]). The most common grade ≥ 3 adverse events up to week 24 were anemia (ruxolitinib: 22.7%; BAT: 6.7%) and pneumonia (22.7% and 20.0%, respectively). Ruxolitinib showed a higher response rate and improvement in failure-free survival in Japanese patients with SR/D chronic GvHD, with a safety profile consistent with the overall study population.

Idiopathic thrombocytopenic purpura (ITP), an autoimmune hematologic disorder characterized by severe platelet count reduction, can be treated with romiplostim. However, post-marketing safety and effectiveness data for romiplostim in Japan are scarce. This prospective, observational, post-marketing Specified Use-Results Survey evaluated the real-world safety and effectiveness of romiplostim for 2 years. All patients treated with romiplostim during the survey period were eligible. Of the 1622 patients in the safety analysis set, 94.08% (1526/1622) had chronic ITP. The mean single dose of romiplostim was stable after 12 weeks and remained < 6 μg/kg in approximately 70% of patients until 104 weeks. Within 2 years, 14.92% of patients discontinued romiplostim because of adverse events, while 6.47% discontinued because of suspected adverse drug reactions. In contrast, 14.00% of patients discontinued romiplostim because of symptom improvement. Before romiplostim initiation, platelet count was < 2.0 × 10⁴/µL in 60.54% of patients, and the mean platelet count was 2.84 ± 5.76 × 10⁴/µL. Platelet count was 9.19 ± 13.01 × 10⁴/µL after 4 weeks, and remained between 10.34 ± 10.72 and 12.38 ± 12.63 × 10⁴/µL from 8 to 104 weeks of treatment. No specific concerns were revealed regarding the safety and effectiveness of romiplostim in chronic ITP; the findings demonstrated a favorable risk-benefit balance for romiplostim in this population. Trial registration: UMIN000047864 ( www.umin.ac.jp/ctr ).

Silent inactivation (SI) of L-asparaginase (ASP) is a phenomenon by which a neutralizing antibody for ASP (AAA) decreases ASP activity (ASA) in patients without a clinical allergy to ASP. Acute lymphoblastic leukemia (ALL) has a poor prognosis in patients with SI. Therefore, measurement of ASA levels, not AAA levels, is needed to identify patients with SI. We herein report the results of the prospective clinical trial ALL-ASP19, the first study in Japan to measure ASA and AAA to identify patients with SI. A total of 110 newly diagnosed ALL patients were enrolled, and ASA levels were measured three times during ALL treatment. Besides the 12 patients who discontinued the study, 32 were excluded due to inappropriate frequency and timing of ASA measurements and inappropriate ASP dosing. The remaining 66 patients were analyzed, and 3 patients with SI (4.5%) were identified. The incidence of SI is lower in Japan than in other countries. AAA was detected in all patients with SI, but four of the seven patients with AAA did not develop SI. Clinical characteristics did not significantly differ between patients with and without SI. Therefore, ASA levels must be measured to identify patients receiving insufficient ASP treatment.

Diffuse large B cell lymphoma (DLBCL) and follicular lymphoma (FL) represent the two major subtypes of mature B cell lymphoma. A deeper understanding of tumor biology, as well as molecular classification characterized by targetable gene alterations, and the introduction of novel treatment options, including targeted drugs (e.g., antibody-drug conjugates and small molecules [e.g., Bruton tyrosine kinase inhibitor]) and immune therapies (e.g., chimeric antigen receptor [CAR] T cell therapy and bispecific antibody [BsAb]), has changed the treatment paradigms for DLBCL and FL. In clinical practice, however, treatment regimens are determined mainly based on prior treatment history, duration of response after previous treatment, patient age, and patient frailty because there have been few randomized trials to inform treatment selection for patients with relapsed or refractory disease and because there is no single prognostic index that guides suitable treatment for each patient. In this review, we summarize the treatment options for DLBCL and FL and discuss the treatment strategies for these two subtypes. We also discuss future perspectives for the treatment of these subtypes.

The Japan Children's Cancer Group Relapsed Acute Lymphoblastic Leukemia (ALL) Committee conducted a prospective observational study (ALL-R14) to explore promising reinduction therapy regimens for relapsed ALL to investigate in future trials. In Japan, clofarabine- and bortezomib-based regimens were of interest since they were newly introduced for ALL in the study period (2015-2018). Seventy-five pediatric patients were enrolled in total. The 2-year event-free/overall survival rates in patients with first (n = 59) or second (n = 11) relapse were 40.1% (95% confidence interval [CI]: 25.5-52.3%)/66.3% (95% CI 52.3-77.0%) and 34.1% (95% CI 9.1-61.6%)/62.3% (95% CI 27.7-84.0%), respectively. Clofarabine- or bortezomib-based regimens were used only in patients with high-risk disease. The first reinduction therapy used in the 41 patients with early or multiple relapsed B-cell precursor ALL was clofarabine in 7 patients and bortezomib in 9 patients. The odds ratio for reinduction failure risk with a clofarabine- or bortezomib-based regimen compared with other regimens was 9.0 (95% CI 0.9-86.4, P = 0.057) or 1.9 (95% CI 0.4-8.7, P = 0.42), respectively. Thus, clofarabine- or bortezomib-based regimens had no obvious advantage as reinduction therapy for relapsed ALL in children.

Mutation profiling by next-generation sequencing (NGS) has facilitated understanding of the molecular pathogenesis of acute myeloid leukemia (AML), and has been incorporated into the new disease classification (International Consensus Classification; ICC) and risk classification (European LeukemiaNet [ELN] 2022; ELN2022). We compared disease subtypes between the previous disease classification (4th edition of the WHO classification; WHO-4) and the ICC in 91 patients with AML diagnosed at our institution. We also compared disease risk classifications using the previous risk classification (ELN2017) and the ELN2022. Targeted sequencing of bone marrow samples was conducted at Kyoto University. We found that entities under AML with recurrent genetic abnormalities were well-established, with almost no change from the WHO-4 to the ICC. In contrast, 16.7% of cases of AML, not otherwise specified in the WHO-4 were reclassified into AML with mutated TP53, and 36.7% were reclassified into AML with myelodysplasia-related gene mutations or cytogenetic abnormalities per the ICC. Meanwhile, the ELN2017 and ELN2022 showed no difference in concordance indexes in multivariate Cox regression analysis for progression-free and overall survival. The superiority of the ELN2022 over the ELN2017 could not be confirmed in our single-center retrospective study, and further investigation including multicenter prospective studies is needed.

Previously, we reported the efficacy and safety of tazemetostat in Japanese patients with relapsed/refractory follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) harboring the EZH2 mutation in a multicenter, open-label, phase II study. Here, we present a follow-up analysis of tazemetostat at a long-term median follow-up of 35.0 months. Twenty patients were enrolled: 17 in the FL cohort and three in the DLBCL cohort. In the FL cohort, the objective response rate was 70.6%, consistent with the primary analysis, and the median progression-free survival (PFS) was not reached. The 24-month and 36-month PFS rates were 72.1% (95% confidence interval [CI] 41.5%-88.6%) and 64.1% (95% CI 33.7%-83.4%), respectively. The median duration of treatment was 30.2 months. After the primary analysis at a median follow-up of 12.9 months, grade 1-2 urinary tract infection, peripheral motor neuropathy, and hypogammaglobulinemia newly emerged, but the incidence of adverse events (AEs) did not increase notably during this follow-up period. No unexpected grade ≥ 3 treatment-related AEs were reported. Long-term oral monotherapy with tazemetostat showed favorable efficacy and safety profiles, indicating that it may be a useful third-line or later treatment option for patients with relapsed/refractory FL harboring the EZH2 mutation. Trial registration: ClinicalTrials.gov: NCT03456726.

Venetoclax was approved for relapsed/refractory chronic lymphocytic leukemia (R/R CLL) and small lymphocytic leukemia (SLL) in Japan in September 2019; however, clinical data in Japanese patients are limited. This all-case post-marketing surveillance assessed efficacy and safety in Japanese patients with R/R CLL/SLL who started venetoclax treatment between November 2019 and August 2020. Overall, the safety and efficacy analysis sets included 129 and 114 patients, respectively. The overall response rate (ORR) was 57.0%; ORRs were higher in patients with versus without concomitant rituximab (65.4% vs. 54.7%), and in patients with 1 versus ≥ 2 prior lines of therapies (72.5% vs. 44.4%). Adverse events (AEs) were reported in 66.7% of patients (86/129); the most common AEs were neutrophil count decreased (22.5%), white blood cell count decreased (7.8%), and tumor lysis syndrome (TLS; 6.2%). AEs of special interest (TLS, myelosuppression, and infection) were manageable in clinical practice in Japan. Venetoclax is efficacious and safe for R/R CLL/SLL patients in the real-world setting in Japan. ClinicalTrials.gov ID: NCT04198415.

Acute lymphoblastic leukemia (ALL) relapsed after allogeneic hematopoietic cell transplantation (allo-HCT) has a catastrophic prognosis. Blinatumomab, a CD3/CD19-directed bispecific T cell engager, is reportedly effective for advanced B-cell ALL (B-ALL), even after allo-HCT. However, the efficacy of blinatumomab in extramedullary relapse (EMR) is controversial. Donor lymphocyte infusion (DLI) is another immunological treatment worth considering for ALL relapsed after allo-HCT. We report the case of a 56-year-old woman with B-ALL. Allo-HCT was performed during the second complete remission (CR). Thirteen months after allo-HCT, isolated EMR (iEMR) of B-ALL developed without bone marrow lesions. A third CR was achieved with 2 cycles of blinatumomab. An additional four cycles each of blinatumomab and DLI were then administered. The patient did not develop graft-versus-host disease and has confirmed 2-year treatment-free remission without a second allo-HCT. Therefore, blinatumomab was considered an effective salvage therapy for iEMR of B-ALL after allo-HCT, because iEMR could have a lower tumor burden than that seen in systemic relapse, and low tumor burden was a prognostic factor for response to blinatumomab. Furthermore, immunological consolidation therapies could only provoke graft-versus-leukemia effects if the imbalanced effector/target ratio was restored and the tumor burden was lowered through immunosurveillance.