Outcomes of pregnancy in patients with chronic myeloid leukemia in the era of tyrosine kinase inhibitors.

BACKGROUND: Young female patients with chronic myeloid leukemia (CML) often face challenges becoming pregnant due to the teratogenicity of tyrosine kinase inhibitors (TKIs). METHODS: The authors conducted a nationwide survey of female patients with CML who experienced pregnancy between 2002 and 2020. RESULTS: Information for 70 pregnancies in 49 patients was obtained. There were three types of pregnancies: CML onset during pregnancy (n = 9), unplanned pregnancy mostly during treatment with a TKI (n = 25), and planned pregnancy during treatment-free remission (TFR) or treatment with interferon-alpha (IFN-α) (n = 36). The median duration from CML diagnosis to pregnancy in patients with planned pregnancy was significantly longer than that in patients with unplanned pregnancy (10.6 years vs. 4.1 years, p < .001). In 48 pregnancies that resulted in childbirth, TFR and treatment with IFN-α were chosen in 26 and 17 pregnancies, respectively. Sustained major or deeper molecular response was observed in 18 of 26 pregnancies with TFR. The patients who fulfilled the requirements for TKI therapy discontinuation by European LeukemiaNet recommendations achieved a TFR rate of 77% in pregnancy. Treatment with IFN-α might be effective for patients who are in complete cytogenetic response or deeper response (response rate, 76%). CONCLUSION: Pregnancy by TFR or treatment with IFN-α could be a safe and feasible way for patients with CML. However, a substantial duration of treatment with a TKI before conception may be needed for planned pregnancy. Planning and evaluation for pregnancy should be considered at the time of CML onset for female patients with childbearing potential.

Development and evaluation of a rapid one-step high sensitivity real-time quantitative PCR system for minor BCR-ABL (e1a2) test in Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL).

OBJECTIVE: Minimal residual disease assessment of BCR-ABL messenger ribonucleic acid levels is crucial in Philadelphia chromosome-positive acute lymphoblastic leukemia for prognosis and treatment planning. However, accurately quantifying minor BCR-ABL transcripts, which comprise 70% of Philadelphia chromosome-positive acute lymphoblastic leukemia cases, lacks a national-approved method. METHODS: We developed the "Otsuka" minor BCR-ABLmessenger ribonucleic acid assay kit with exceptional precision (0.00151%). Minor BCR-ABL messenger ribonucleic acid levels were analyzed in 175 adults, 36 children with acute lymphoblastic leukemia and 25 healthy individuals to evaluate the kit's performance. RESULTS: The "Otsuka" kit showed high concordance with a commonly used chimeric gene screening method, indicating reliable detection of positive cases. Quantitative results demonstrated a robust correlation with both a laboratory-developed test and a diagnostic research product. The "Otsuka" kit performs comparably or even surpass to conventional products, providing valuable insights into Philadelphia chromosome-positive acute lymphoblastic leukemia pathology. CONCLUSIONS: The 'Otsuka" minor BCR-ABL messenger ribonucleic acid assay kit exhibits excellent performance in quantifying minor BCR-ABL transcripts in Philadelphia chromosome-positive acute lymphoblastic leukemia patients. Our results align well with established screening methods and show a strong correlation with laboratory-developed tests and diagnostic research products. The "Otsuka" kit holds great promise as a valuable tool for understanding Philadelphia chromosome-positive acute lymphoblastic leukemia pathology and guiding effective treatment strategies.

Venetoclax plus low-dose cytarabine in patients with newly diagnosed acute myeloid leukemia ineligible for intensive chemotherapy: an expanded access study in Japan.

BACKGROUND: In a Phase 3 international clinical trial (VIALE-C), venetoclax plus low-dose cytarabine improved the response rate and overall survival versus placebo plus low-dose cytarabine in patients with newly diagnosed acute myeloid leukemia who were ineligible for intensive chemotherapy. After the enrollment period of VIALE-C ended, we conducted an expanded access study to provide preapproval access to venetoclax in combination with low-dose cytarabine in Japan. METHODS: Previously, untreated patients with acute myeloid leukemia who were ineligible for intensive chemotherapy were enrolled according to the VIALE-C criteria. Patients received venetoclax (600 mg, Days 1-28, 4-day ramp-up in Cycle 1) in 28-day cycles and low-dose cytarabine (20 mg/m2, Days 1-10). All patients took tumor lysis syndrome prophylactic agents and hydration. Safety endpoints were assessed. RESULTS: Fourteen patients were enrolled in this study. The median age was 77.5 years (range = 61-84), with 78.6% over 75 years old. The most common grade ≥ 3 treatment-emergent adverse event was neutropenia (57.1%). Febrile neutropenia was the most frequent serious adverse event (21.4%). One patient developed treatment-related acute kidney injury, leading to discontinuation of treatment. Two patients died because of cardiac failure and disease progression that were judged not related to study treatment. No patients developed tumor lysis syndrome. CONCLUSIONS: The safety outcomes were similar to those in VIALE-C without new safety signals and were well managed with standard medical care. In clinical practice, more patients with severe background disease are expected, in comparison with in VIALE-C, suggesting that it is important to carefully manage and prevent adverse events.

Venetoclax plus azacitidine in Japanese patients with untreated acute myeloid leukemia ineligible for intensive chemotherapy.

BACKGROUND: The phase 3 VIALE-A trial (NCT02993523) reported that venetoclax-azacitidine significantly prolonged overall survival compared with placebo-azacitidine in patients with newly diagnosed acute myeloid leukemia ineligible for intensive chemotherapy. Herein, efficacy and safety of venetoclax-azacitidine are analyzed in the Japanese subgroup of VIALE-A patients. METHODS: Eligible Japanese patients were randomized 2:1 to venetoclax-azacitidine (N = 24) or placebo-azacitidine (N = 13). Primary endpoints for Japan were overall survival and complete response (CR) + CR with incomplete hematologic recovery (CRi). Venetoclax (target dose 400 mg) was given orally once daily. Azacitidine (75 mg/m2) was administered subcutaneously or intravenously on Days 1-7 of each 28-day cycle. RESULTS: Median follow-up was 16.3 months (range, 1.0-20.3). Median overall survival was not reached with venetoclax-azacitidine (hazard ratio 0.409 and 95% confidence interval: 0.151, 1.109); overall survival estimate was higher with venetoclax-azacitidine than placebo-azacitidine at 12 (67 and 46%) and 18 months (57 and 31%), respectively. CR and CRi rates were 67% with venetoclax-azacitidine and 15% with placebo-azacitidine. Most common any-grade adverse events were febrile neutropenia (79 and 39%), thrombocytopenia (54 and 77%), constipation (54 and 54%) and decreased appetite (54 and 38%) in the venetoclax-azacitidine and placebo-azacitidine arms, respectively. Only 1 patient in the venetoclax-azacitidine arm, and no patients in the placebo-azacitidine arm, had grade 4 febrile neutropenia that led to treatment discontinuation. CONCLUSIONS: This Japanese subgroup analysis of VIALE-A demonstrates comparable safety and efficacy outcomes compared with the global study and supports venetoclax-azacitidine as first-line standard-of-care for Japanese treatment-naive patients with acute myeloid leukemia who are ineligible for intensive chemotherapy.

Impact of the Clinical Trials Act on Noncommercial Clinical Research in Japan: An Interrupted Time-series Analysis.

BACKGROUND: The number of new noncommercial clinical studies conducted in Japan declined within the first year of the implementation of the Clinical Trials Act (CTA) on April 1, 2018. This study aimed to examine the impact of the CTA's enforcement on the number of new noncommercial clinical studies registered in the Japanese Clinical Trial Registry. METHODS: An interrupted time-series design was used in the analysis, which was conducted from April 2015 to March 2019. We collected data for studies registered in the Clinical Trial Registry, managed by the University Hospital Medical Information Network. RESULTS: In total, 35,811 studies were registered; of these, 16,455 fulfilled the eligibility criteria. The difference in the trend of monthly number of new studies after CTA enforcement decreased significantly by 15.0 (95% confidence interval [CI], -18.7 to -11.3), and the level decreased by 40.8 (95% CI, -68.2 to -13.3) studies from the pre-enforcement to the post-enforcement period. Multigroup analyses indicated that the act exerted a significant effect on the trend of new clinical studies, particularly those with smaller sample sizes, interventional study designs, and nonprofit funding sponsors. CONCLUSIONS: The number of Japanese noncommercial clinical studies declined significantly following implementation of the CTA. It is necessary to establish a system to promote clinical studies in Japan while ensuring transparency and safety.

[Acute myeloid leukemia harboring NUP98::DDX10].

NUP98::DDX10 is a rare fusion gene associated with acute myeloid leukemia (AML), for which the prognosis and indication for allogeneic hematopoietic stem cell transplantation are unknown. A 48-year-old woman was diagnosed with AML harboring NUP98::DDX10. The results of quantitative RT-PCR of the fusion mRNA as a minimal residual disease (MRD) marker guided the treatment. In August 2019, the patient achieved hematological remission following standard remission induction therapy with idarubicin and cytarabine. After four cycles of consolidation therapies, MRD was detected, and she underwent allogeneic stem cell transplantation in May 2020. As MRD persisted in June, the immunosuppressant was stopped and three cycles of azacitidine were administered. Despite this, a hematological relapse occurred in January 2021 that was resistant to high-dose cytarabine and an investigational agent. She died as a result of the disease's progression. Thus, a second thought should be given to the timing of transplantation, the bridging, and the intervention for relapse after transplantation. The cases must be accumulated.

Venetoclax plus low-dose cytarabine in Japanese patients with untreated acute myeloid leukaemia ineligible for intensive chemotherapy.

BACKGROUND: In a multinational phase 3 trial (VIALE-C), venetoclax plus low-dose cytarabine prolonged overall survival vs placebo plus low-dose cytarabine in patients with newly diagnosed acute myeloid leukaemia ineligible for intensive chemotherapy, although it was not statistically significant. Herein, we assess the benefit of venetoclax plus low-dose cytarabine in the Japanese subgroup of VIALE-C patients (n = 27). METHODS: VIALE-C, a randomized (2:1), double-blind study (NCT03069352), enrolled untreated patients (≥18 years) with acute myeloid leukaemia. Patients received venetoclax (600 mg days 1-28, 4-day ramp-up in cycle 1) or placebo in 28-day cycles with low-dose cytarabine (20 mg/m2 days 1-10). The primary endpoint was median overall survival. RESULTS: In the Japanese subgroup, at a 6-month follow-up from the primary analysis, median overall survival for venetoclax (n = 18) and placebo (n = 9), plus low-dose cytarabine, was 4.7 and 8.1 months, respectively (hazard ratio, 0.928, 95% confidence intervals : 0.399, 2.156). The rate of complete remission plus complete remission with incomplete blood count recovery was higher with venetoclax plus low-dose cytarabine (44.4%) vs placebo plus low-dose cytarabine (11.1%). All patients experienced at least 1 adverse event. The most common grade ≥3 adverse events with venetoclax or placebo, plus low-dose cytarabine, were febrile neutropenia (50.0% vs 44.4%, respectively) and thrombocytopenia (27.8% vs 44.4%, respectively). Serious adverse events were reported in 50.0 and 33.3% of patients in the venetoclax and placebo, plus low-dose cytarabine arms, respectively; pneumonia was the most common (22.2% each). CONCLUSIONS: Limited survival benefit in the Japanese subgroup can be attributed to small patient numbers and to baseline imbalances observed between treatment arms, with more patients in the venetoclax plus low-dose cytarabine arm presenting poor prognostic factors. Venetoclax plus low-dose cytarabine was well tolerated in Japanese patients with acute myeloid leukaemia ineligible for intensive chemotherapy.

[Acquired platelet dysfunction with severe bleeding tendency in triple-negative myelofibrosis].

A 50-year-old man demonstrated markedly increased number of white blood cells, anemia, severe splenomegaly, and bleeding tendency. Bone marrow analysis revealed remarkable hypercellularity; dysplasia in multilineage cells, including megakaryocytes; and fibrosis. He was eventually diagnosed with triple-negative myelofibrosis. A massive hematoma developed at the bone marrow biopsy site. A similar episode recurred after the second bone marrow biopsy. The von Willebrand factor and other coagulation factor activities were within normal ranges. Platelet aggregation analyses demonstrated highly impaired aggregation induced by ADP, collagen, and epinephrine. Treatment with hydroxyurea and ruxolitinib, a JAK inhibitor, was ineffective, and he eventually died on day 144 after hospitalization. Acquired platelet dysfunction uncommonly occurs in patients with myelodysplastic syndromes (MDS) and myeloproliferative neoplasms (MPN), without precise elucidation of the frequency and underlying mechanism. The onset of bleeding tendency in the current patient suggested that platelet dysfunction may be caused by somatic genetic events. Here, we discuss the mechanisms of acquired platelet dysfunction in MDS or MPN with a literature review.

Silent NK/T cell reactions to dasatinib during sustained deep molecular response before cessation are associated with longer treatment-free remission.

This study presents the final report of the multicenter, prospective tyrosine kinase inhibitor discontinuation study, D-STOP, after a 3-year follow-up of 54 patients with chronic CML who discontinued dasatinib after a sustained deep molecular response (DMR) for ≥2 years with dasatinib treatment. Estimated treatment-free remission (TFR) rates at 12 and 36 months were 63.0% [95% confidence interval (CI): 48.7-74.3] and 59.3% (95% CI: 45.0-71.0), respectively. CD3- CD56+ NK, CD16+ CD56+ NK, and CD57+ CD56+ NK large granular lymphocyte (NK-LGL), CD8+ CD4- cytotoxic T cell, and CD57+ CD3+ T-LGL cell numbers were relatively elevated throughout the 24-month consolidation only in failed patients who molecularly relapsed within 12 months. In successful patients, these subsets elevated transiently after 12 months, but returned to basal levels after 24-month consolidation. Therefore, smaller changes in NK/T, particularly the NK subset throughout consolidation, reflected higher TFR rates. TFR rates of those patients exhibiting elevation in CD3- CD56+ NK >376 cells/µL, CD16+ CD56+ NK > 241 cells/µL, or CD57+ CD56+ NK-LGL >242 cells/µL during consolidation compared with others were 26.7% (8.3%-49.6%) vs 78.3% (55.4%-90.3%), HR 0.032 (0.0027-0.38; P = .0064), 31.2% (11.4%-53.6%) vs 85.0% (60.4%-94.9%), HR 0.039 (0.0031-0.48; P = .011), or 36.8% (16.5%-57.5%) vs 77.3% (53.7%-89.8%), HR 0.21 (0.065-0.69; P = .010), respectively. Therefore, silent responses of T/NK subsets to dasatinib throughout consolidation were significant for longer TFR. Elevated NK/T, particularly NK lymphocytes responsive to dasatinib, may be immunologically insufficient to maintain TFR. Their decline, subsequently replaced by altered lymphocyte population with less response to dasatinib during sustained DMR, might be immunologically significant. (D-STOP, NCT01627132).

Correction to: Impact of oral voriconazole during chemotherapy for acute myeloid leukemia and myelodysplastic syndrome: a Japanese nationwide retrospective cohort study.

In the original publication, in Figure 1 the month range of DPC Database has been given incorrectly.

Intravenous itraconazole compared with liposomal amphotericin B as empirical antifungal therapy in patients with neutropaenia and persistent fever.

BACKGROUND: Fungal infections are a major complication of neutropaenia following chemotherapy. Their early diagnosis is difficult, and empirical antifungal treatment is widely used, and uses of less toxic drugs that reduce breakthrough infection are required. OBJECTIVE: We conducted a multicentre, open-label, randomised, non-inferiority trial to compare the safety and efficacy of intravenous itraconazole (ivITCZ) and liposomal amphotericin B (LAmB) as empirical antifungal therapy in patients with haematological malignancies with neutropaenia and persistent fever. METHODS: Patients with haematological malignancies who developed fever refractory to broad-spectrum antibacterial agents under neutropaenia conditions were enrolled. Patients were randomised for treatment with LAmB (3.0 mg/kg/d) or ivITCZ (induction: 400 mg/d, maintenance: 200 mg/d). RESULTS: Observed overall favourable response rates of 17/52 (32.7%) and 18/50 (36.0%) in the LAmB and ivITCZ groups, with a model-based estimate of a 4% difference (90% CI, -12% to 20%), did not fulfil the statistical non-inferiority criterion. In the LAmB group, there were two cases of breakthrough infection and five cases of probable invasive fungal disease, whereas in the itraconazole group, neither breakthrough infection nor probable invasive fungal disease occurred. Patients in the ivITCZ group had significantly fewer grade 3-4 hypokalaemia-related events than LAmB group patients (P < .01). The overall incidence of adverse events tended to be lower in the ivITCZ group (P = .07). CONCLUSION: ivITCZ showed similar efficacy and safety as LAmB as empirical antifungal therapy in haematological malignancy patients with febrile neutropaenia, although the small sample size and various limitations prevented demonstration of its non-inferiority.

Efficacy and Safety of a Weekly Cyclophosphamide-Bortezomib-Dexamethasone Regimen as Induction Therapy Prior to Autologous Stem Cell Transplantation in Japanese Patients with Newly Diagnosed Multiple Myeloma: A Phase 2 Multicenter Trial.

We assessed the efficacy and safety of weekly cyclophosphamide-bortezomib-dexamethasone (CBD) induction prior to autologous stem cell transplantation (ASCT) in newly diagnosed Japanese patients with multiple myeloma (MM). This regimen consisted of four 28-day cycles of once-weekly oral cyclophosphamide (300 mg/m2), subcutaneous bortezomib (1.3 mg/m2), and oral dexamethasone (40 mg). Responding patients underwent stem cell collection followed by ASCT. The primary endpoint was the postinduction rate of achieving a near complete response (nCR) or better. Among the 38 enrolled patients, a complete response (CR), an nCR, a very good partial response (VGPR), and a partial response (PR) were achieved in 10.5, 2.6, 23.7, and 36.8% of cases, respectively. A grade 4 hematological adverse event (AE) was observed in 1 patient. Grade 3-4 infection, including febrile neutropenia, was observed in 4 patients (10.5%). Although 2 patients dropped out due to AE, 94.7% of the patients completed the induction phase. However, because of a poor response to induction chemotherapy (

Impact of oral voriconazole during chemotherapy for acute myeloid leukemia and myelodysplastic syndrome: a Japanese nationwide retrospective cohort study.

BACKGROUND: The prevention of invasive fungal infections is important in patients with acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) receiving cytoreductive chemotherapy. However, the role of oral voriconazole (VRCZ) in such patients has not been established. This study aimed to investigate the effectiveness of oral VRCZ compared to that of first-generation azoles prescribed within 7 days after the onset of chemotherapy in adult patients with AML/MDS using the Japanese administrative database. METHODS: This nationwide retrospective cohort study was conducted using the Diagnosis Procedure Combination/Per-Diem Payment System. The primary outcome was the proportion of patients who switched to intravenous antifungal agents. Analyses using the instrumental variable method were performed to address unmeasured confounding. RESULTS: In total, data on 5517 inpatients from 142 hospitals were analyzed. An oral VRCZ prescription was significantly associated with a reduction in the proportion of patients switching to intravenous antifungal agents compared to first-generation azole prescription (21.0% (95% confidence interval [CI] - 33.4 to - 8.6)). The impact of oral VRCZ in reducing the proportion of patients switching to intravenous antifungal agents was stronger in patients aged < 65 years than in those aged ≥ 65 years (- 40.6%, 95% CI - 63.2 to - 17.9; - 21.9%, 95% CI - 35.8 to - 8.1, respectively) and in patients prescribed oral azole within 3 days from the onset of chemotherapy than in those prescribed the same later (- 32.9%, 95% CI - 46.7 to - 19.2; - 9.0%, 95% CI - 33.7 to 15.7, respectively). CONCLUSION: Oral VRCZ administration may benefit adult patients with AML/MDS undergoing chemotherapy.

Feasibility of the imatinib stop study in the Japanese clinical setting: delightedly overcome CML expert stop TKI trial (DOMEST Trial).

BACKGROUND: Treatment-free remission (TFR), the ability to maintain a molecular response (MR), occurs in approximately 50% of patients with chronic myelogenous leukemia (CML) treated with tyrosine kinase inhibitors (TKIs). METHODS: A multicenter phase 2 trial (Delightedly Overcome CML Expert Stop TKI Trial: DOMEST Trial) was conducted to test the safety and efficacy of discontinuing imatinib. Patients with CML with a sustained MR of 4.0 or MR4.0-equivalent for at least 2 years and confirmed MR4.0 at the beginning of the study were enrolled. In the TFR phase, the international scale (IS) was regularly monitored by IS-PCR testing. Molecular recurrence was defined as the loss of MR4.0. Recurrent patients were immediately treated with dasatinib or other TKIs including imatinib. RESULTS: Of 110 enrolled patients, 99 were evaluable. The median time from diagnosis to discontinuation of imatinib was 103 months, and the median duration of imatinib therapy was 100 months. Molecular recurrence-free survival rates were 69.6%, 68.6% and 64.3% at 6, 12, and 24 months, respectively. After discontinuation of imatinib therapy, 26 patients showed molecular recurrence, and 25 re-achieved deep MR after dasatinib treatment. Molecular response MR4.0 was achieved in 23 patients within 6 months and 25 patients within 12 months. Multivariate analysis revealed that a longer time from diagnosis to discontinuation of imatinib therapy (p = 0.0002) and long duration of imatinib therapy (p = 0.0029) predicted a favorable prognosis. CONCLUSIONS: This DOMEST Trial showed the feasibility of TKI discontinuation in a Japanese clinical setting.

[Successful Treatment of T-Cell Prolymphocytic Leukemia with Alemtuzumab].

T-cell prolymphocytic leukemia(T-PLL)is a highly aggressive hematopoietic malignancy with poor prognosis and is extremely rare in Japan. Since T-PLL cells usually express high levels of CD52, the anti-CD52 monoclonal antibody alemtuzumab is expected to exhibit an antitumor effect via its antibody-dependent cell cytotoxicity(ADCC)and complement-dependent cytotoxicity(CDC). However, the therapeutic efficiency of alemtuzumab for T-PLL has not been established in Japan. Furthermore, only a few patients have completed the treatment schedule because of adverse events. Here, we report a 64-yearold woman with multiple comorbidities who was successfully treated with alemtuzumab.

Dasatinib cessation after deep molecular response exceeding 2 years and natural killer cell transition during dasatinib consolidation.

Tyrosine kinase inhibitors (TKI) improve the prognosis of patients with chronic myelogenous leukemia (CML) by inducing substantial deep molecular responses (DMR); some patients have successfully discontinued TKI therapy after maintaining DMR for ≥1 year. In this cessation study, we investigated the optimal conditions for dasatinib discontinuation in patients who maintained DMR for ≥2 years. This study included 54 patients with CML who were enrolled in a D-STOP multicenter prospective trial, had achieved DMR, and had discontinued dasatinib after 2-year consolidation. Peripheral lymphocyte profiles were analyzed by flow cytometry. The estimated 12-month treatment-free survival (TFS) was 62.9% (95% confidence interval: 48.5%-74.2%). During dasatinib consolidation, the percentage of total lymphocytes and numbers of CD3- CD56+ natural killer (NK) cells, CD16+ CD56+ NK cells and CD56+ CD57+ NK-large granular lymphocytes (LGL) were significantly higher in patients with molecular relapse after discontinuation but remained unchanged in patients without molecular relapse for >7 months. At the end of consolidation, patients whose total lymphocytes comprised <41% CD3- CD56+ NK cells, <35% CD16+ CD56+ NK cells, or <27% CD56+ CD57+ NK-LGL cells had higher TFS relative to other patients (77% vs 18%; P < .0008; 76% vs 10%; P < .0001; 84% vs 46%; P = .0059, respectively). The increase in the number of these NK cells occurred only during dasatinib consolidation. In patients with DMR, dasatinib discontinuation after 2-year consolidation can lead to high TFS. This outcome depends significantly on a smaller increase in NK cells during dasatinib consolidation.

Dasatinib rapidly induces deep molecular response in chronic-phase chronic myeloid leukemia patients who achieved major molecular response with detectable levels of BCR-ABL1 transcripts by imatinib therapy.

BACKGROUND: With the introduction of imatinib, a first-generation tyrosine kinase inhibitor (TKI) to inhibit BCR-ABL1 kinase, the outcome of chronic-phase chronic myeloid leukemia (CP-CML) has improved dramatically. However, only a small proportion of CP-CML patients subsequently achieve a deep molecular response (DMR) with imatinib. Dasatinib, a second-generation TKI, is more potent than imatinib in the inhibition of BCR-ABL1 tyrosine kinase in vitro and more effective in CP-CML patients who do not achieve an optimal response with imatinib treatment. METHODS: In the present study, we attempted to investigate whether switching the treatment from imatinib to dasatinib can induce DMR in 16 CP-CML patients treated with imatinib for at least two years who achieved a major molecular response (MMR) with detectable levels of BCR-ABL1 transcripts. RESULTS: The rates of achievement of DMR at 1, 3, 6 and 12 months after switching to dasatinib treatment in the 16 patients were 44% (7/16), 56% (9/16), 63% (10/16) and 75% (12/16), respectively. The cumulative rate of achieving DMR at 12 months from initiation of dasatinib therapy was 93.8% (15/16). The proportion of natural killer cells and cytotoxic T cells in peripheral lymphocytes increased after switching to dasatinib. In contrast, the proportion of regulatory T cells decreased during treatment. The safety profile of dasatinib was consistent with previous studies. CONCLUSION: Switching to dasatinib would be a therapeutic option for CP-CML patients who achieved MMR but not DMR by imatinib, especially for patients who wish to discontinue TKI therapy.

Haploidentical transplantation using post-transplant high-dose cyclophosphamide for adult T-cell lymphoma after mogamulizumab treatment.

A 53-year-old man diagnosed with adult T-cell lymphoma (ATL) was treated with mLSG15 chemotherapy and achieved a first complete remission. Subsequently, a liver tumor emerged that was pathologically diagnosed as ATL (first relapse). A second remission was achieved after local irradiation and four cycles of mogamulizumab treatment. The patient received peripheral blood stem cell transplantation (HSCT) from a one haplotype HLA-mismatched daughter after total body irradiation and the administration of fludarabine as a myeloablative conditioning regimen, followed by post-transplant cyclophosphamide. While subsequent acute graft-versus-host disease (GVHD) was never more than Grade I, severe chronic GVHD (cGVHD) developed in the oral cavity and skin that was resistant to escalated doses of cyclosporine and prednisolone. The patient subsequently had a second relapse of ATL as a subcutaneous mass and eventually died of disease progression. Mogamulizumab is a humanized monoclonal IgG that targets CC chemokine receptor 4 (CCR4) and is a key treatment option for relapsed ATL. It reportedly increases the risk of acute GVHD after HSCT due to the depletion of CCR4-positive regulatory T-cells; however, information on its impact on cGVHD is unavailable. Here, we discuss the potential risks and benefits of mogamulizumab, particularly in a haploidentical donor setting during a HSCT for ATL.

Shorter halving time of BCR-ABL1 transcripts is a novel predictor for achievement of molecular responses in newly diagnosed chronic-phase chronic myeloid leukemia treated with dasatinib: Results of the D-first study of Kanto CML study group.

To investigate the factors that affect molecular responses on dasatinib treatment in patients with chronic-phase chronic myeloid leukemia (CML-CP), we performed a clinical trial named the "D-First study." Fifty-two patients with newly diagnosed CML-CP were enrolled in this study and received 100 mg dasatinib once daily. A deep molecular response (DMR) was defined as <50 copies/µg RNA of BCR-ABL1 transcript value corrected by GAPDH, which ensures <0.01% of BCR-ABL1 transcript value according to International Scale (BCR-ABL1(IS)). The halving time for BCR-ABL1 transcripts was calculated using transcript levels before dasatinib treatment, transcript levels after 3 months of treatment, and the treatment time between these two points. In terms of molecular response, 38 of 51 (75%) patients reached major molecular response (MMR) by 12 months, and the rate of DMR by 18 months was 59% (30/51). While both BCR-ABL1 transcript levels before treatment and a shorter halving time of BCR-ABL1 transcripts (≤14 days) were significant factors affecting achievement of MMR by 12 months, the Sokal score at diagnosis was not associated with MMR. Importantly, the halving time was the only factor that predicted achievement of DMR by 18 months. We showed that patients with CML-CP treated with dasatinib can be stratified according to the early treatment response as determined by the halving time of BCR-ABL1 transcripts. These data emphasize the significance of the early response from dasatinib treatment in achieving a DMR. (ClinicalTrials.gov; NCT01464411).

Early cytotoxic lymphocyte expansion contributes to a deep molecular response to dasatinib in patients with newly diagnosed chronic myeloid leukemia in the chronic phase: results of the D-first study.

Dasatinib is one of the key treatment options for chronic myeloid leukemia (CML) patients. Increase in lymphocyte counts has been known to be predictive of a good treatment response under dasatinib treatment as a second line therapy. However, clinical significance of lymphocyte dynamics in the upfront setting has yet to be clarified. To investigate the significance of lymphocyte dynamics in newly diagnosed chronic phase (CP)-CML, patient data of D-First study (ClinicalTrials.gov NCT01464411) were analyzed. Fifty-two CML-CP patients enrolled to this study were treated with dasatinib (100 mg day(-1) ) and all were followed-up for 18 months. The incidence of lymphocyosis was observed in 14 (27%), but it was not associated with deep molecular response achievement. However, natural killer (NK) cell or cytotoxic T lymphocyte (CTL) counts at 1 month were significantly higher in patients with deep molecular response (DMR) by 18 months compared to those without DMR. When the patients were divided into two groups according to those calculated thresholds by receiver operating characteristic curve (407/µL for NK cells and 347/µL for CTLs), the cumulative DMR rates by 18 months were significantly better in higher value group compared to lower value group. In contrast, regulatory T cell counts were significantly lower at 12 and 15 months in patients achieved DMR. These results suggest the presence of dual effects of dasatinib on immune system through the cytotoxic lymphocytes activation and Treg deregulation in different periods in newly diagnosed CML-CP.