Ruxolitinib in steroid-refractory acute graft-vs-host disease: Japanese subgroup analysis of the randomized REACH2 trial.

Acute graft-versus-host disease (aGvHD) is a major complication after allogeneic hematopoietic stem cell transplantation in Japan and other countries. Nearly one-third of patients do not respond to standard systemic steroid therapy and no standard second-line treatment has been established in Japan. We report efficacy and safety findings of ruxolitinib versus best available therapy (BAT) from a subgroup analysis of the international, phase 3 REACH2 study in Japanese patients with steroid-refractory aGvHD. The primary endpoint was overall response rate (ORR) at day 28. Overall, 9 patients received ruxolitinib and 21 received BAT. The ORR at day 28 (88.9% vs 52.4%) and durable ORR at day 56 (66.7% vs 28.6%) were higher with ruxolitinib versus BAT. The estimated cumulative incidence of loss of response at 6 months was 12.5% with ruxolitinib and 18.2% with BAT. The median failure-free survival was longer with ruxolitinib versus BAT (2.73 vs 1.25 months). The most common adverse events up to day 28 in the ruxolitinib and BAT groups were anemia (55.6% vs 19.0%) and thrombocytopenia (44.4% vs 4.8%, respectively). Ruxolitinib showed better efficacy outcomes and a consistent safety profile compared with BAT in the Japanese subgroup, and the findings were consistent with overall study results.

C16, a PKR inhibitor, suppresses cell proliferation by regulating the cell cycle via p21 in colorectal cancer.

Double-stranded RNA-activated protein kinase R (PKR) is highly expressed in colorectal cancer (CRC). However, the role of PKR in CRC remains unclear. The aim of this study was to clarify whether C16 (a PKR inhibitor) exhibits antitumor effects and to identify its target pathway in CRC. We evaluated the effects of C16 on CRC cell lines using the MTS assay. Enrichment analysis was performed to identify the target pathway of C16. The cell cycle was analyzed using flow cytometry. Finally, we used immunohistochemistry to examine human CRC specimens. C16 suppressed the proliferation of CRC cells. Gene Ontology (GO) analysis revealed that the cell cycle-related GO category was substantially enriched in CRC cells treated with C16. C16 treatment resulted in G1 arrest and increased p21 protein and mRNA expression. Moreover, p21 expression was associated with CRC development as observed using immunohistochemical analysis of human CRC tissues. C16 upregulates p21 expression in CRC cells to regulate cell cycle and suppress tumor growth. Thus, PKR inhibitors may serve as a new treatment option for patients with CRC.

Pretransplantation predictors of survival in nonremission acute myeloid leukemia treated with haploidentical transplantation using steroid-based GVHD prophylaxis.

Haploidentical hematopoietic cell transplantation (HCT) using glucocorticoids for acute graft-versus-host disease prophylaxis (GC-haplo) may become a curative treatment option for nonremission acute myeloid leukemia (AML). This retrospective study aimed to identify pre-HCT predictors of survival in a cohort of 97 nonremission AML treated with GC-haplo in Hyogo Medical University Hospital between 2010 and 2020. Relapse and primary induction failure included in 70 (72%) and 27 (28%) patients, respectively. Sixty-one patients (63%) had undergone previous HCT. Multivariate analysis revealed that ≤ 6 months' duration between first complete remission (CR1) and first relapse (Rel1) (CR1-Rel1 interval) (hazard ratio 2.11, 95% confidence interval [CI] 1.15-3.89, P = 0.016) and serum albumin before starting the conditioning treatment of ≤ 3.5 g/dL (hazard ratio 1.80, 95%CI 1.09-2.96, P = 0.022) as risk factors for overall survival. Among three groups categorized according to serum albumin and CR1-Rel1 interval, the best 3-year overall survival was observed in patients with albumin > 3.5 g/dL and CR1-Rel1 interval > 6 months or primary induction failure (50.2%, 95%CI 28.9%-68.3%, P < 0.001), revealing that survival could be predicted using albumin and past CR duration in patients with very high-risk AML not in remission before GC-haplo.

Long-term Use of Ibrutinib in Japanese Patients with Steroid Dependent/Refractory cGVHD: Final Analysis of Multicenter Study.

Background: Chronic graft-versus-host disease (cGVHD) is a serious complication after allogeneic stem cell transplantation. Poor prognosis has been shown in patients with cGVHD after the failure of primary steroid-based treatments. A previous report demonstrated the efficacy and safety of ibrutinib in these patients, leading to the approval of ibrutinib for cGVHD in Japan. Here, we report the extended follow-up of patients in this study. Objectives: To evaluate the safety and efficacy of ibrutinib in Japanese patients with steroid-dependent or refractory cGVHD. Study Design: An open-label, single-arm, multicenter study of ibrutinib in Japanese patients with steroid-dependent or refractory cGVHD (NCT No.: NCT03474679; Clinical Registry No.: CR108443). Results: At the time of the final data cutoff, 7/19 (36.8%) patients completed the study treatment, and 12/19 (63.2%) patients discontinued ibrutinib. After a median follow-up of 31.11 months (range:1.9 to 38.6 months), the best overall response rate was 84.2% (16/19 patients; 95% CI:60.4%, 96.6%) in all treated populations, with a median time to response of 2.81 (range:1.0 to 27.6) months. Of 15 responders with ≥2 organs involved at baseline, seven (46.7%) had responses in multiple organs. An improvement in the organ response rate was observed for the skin, eye, mouth, and esophagus compared with that in a previous report. The rate of sustained response for ≥20 weeks, ≥32 weeks, and ≥44 weeks were 68.8%, 62.5%, and 50.0%, respectively for 16 responders. The median daily corticosteroid dose requirement tended to decrease over time for all treated analysis sets. Twelve of 19 patients (63.2%) reached a corticosteroid dose of <0.15 mg/kg/day for at least one week, and four (21.1%) discontinued corticosteroid treatment for at least 28 days during the study. The failure-free and overall survival rates at 30 months were 62.7% and 62.0%, respectively. The safety findings of this updated analysis were consistent with the safety profile observed at the time of the primary analysis and the known ibrutinib safety profile. Common grade ≥3 treatment-emergent adverse events (TEAEs) were pneumonia (6/19 [31.6%] patients), platelet count decreased, and cellulitis (3/19 [15.8%] patients each). After the primary analysis, no new TEAEs leading to death, treatment discontinuation, or dose reduction were reported, and no new patients reported major hemorrhage. Cardiac arrhythmia (Grade 2 atrial flutter) was reported in 1/19 (5.3%) patients. No new safety signs were observed despite prolonged ibrutinib exposure. Conclusions: The final results support previous conclusions, demonstrating a clinically meaningful response and acceptable safety profile of ibrutinib in Japanese patients with steroid-dependent or refractory cGVHD.

Association of High Mobility Group Box-Protein 1 and Platelet Microparticles in Patients After Hematopoietic Stem Cell Transplantation.

Thrombotic complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT) significantly impact transplant outcomes. We focused on high mobility group box-protein (HMGB)1, one causative agent of thrombotic lesions in allo-HSCT, and investigated its association with platelets. We statistically analyzed available data from 172 patients with hematopoietic malignancies receiving allo-HSCT. A significant enhancement of monocyte-chemotactant protein-1, HMGB1, and platelet-derived microparticle (PDMP) levels was observed at day 0 after transplantation as compared to pre-transplantation. Multivariate analysis of the association among HMGB1 and 16 factors on day 0 revealed a significant correlation of HMGB1 levels with thrombin-antithrombin complex, interleukin-6, and PDMPs. High mobility group box-protein 1-induced procoagulant platelet induction and PDMP generation were performed in vitro using healthy platelets. High mobility group box-protein 1-induced PDMP generation was suppressed by toll-like receptor inhibitors and recombinant thrombomodulin. These results suggest that HMGB1 contributes to platelet activation in patients after allo-HSCT and is associated with PDMP-related thrombotic complications.

Real-world data from yttrium-90 ibritumomab tiuxetan treatment of relapsed or refractory indolent B-cell non-Hodgkin's lymphoma: J3Zi Study.

Yttrium-90 ibritumomab tiuxetan (90YIT) is a radioimmunotherapy agent in which the radioisotope yttrium-90 is bound to ibritumomab via tiuxetan as a chelating agent, and is used for relapsed or refractory low-grade B-cell non-Hodgkin's lymphoma (rr-B-NHL). We conducted a joint study to evaluate the clinical outcome of 90YIT. The J3Zi study is composed of data from patients receiving 90YIT for rr-B-NHL from the top three institutions with 10 years of 90YIT treatment experience from October 2008 to May 2018 in Japan. The efficacy, prognostic factors and safety of 90YIT were retrospectively evaluated. Data from 316 patients were analyzed; the mean age was 64.6 years and the median number of prior treatments was 2. The median PFS was 3.0 years, the final OS rate was over 60%, and the median OS was not reached during the study period. Significant factors influencing PFS were sIL-2R ≤ 500 (U/mL) and no disease progression within 24 months of first treatment. Significant factors influencing OS were number of prior treatments ≤ 2 and sIL-2R ≤ 500 (U/mL). The PFS and OS rates were found to be significantly higher in the late half era (2013 to 2018) than in the early half era (2008 to 2013) during the study period. Prognosis following 90YIT treatment was improved in the late half era compared to the early half era. As treatment using 90YIT increased, administration of 90YIT shifted to the earlier treatment line. This may have contributed to the improvement of prognosis found in the late era. (UMIN000037105).

T-cell lymphoma, B-cell lymphoma, and myelodysplastic syndrome harboring common mutations: Trilineage tumorigenesis from a common founder clone.

A 64-year-old man with angioimmunoblastic T-cell lymphoma (AITL) subsequently developed diffuse large B-cell lymphoma (DLBCL) and myelodysplastic syndrome (MDS). Genomic profiling of AITL, DLBCL, and MDS samples revealed that the tumor cells from all samples shared common mutations in TET2 and DNMT3A. In addition, the IDH2 mutation was observed in AITL, and TP53 mutation was observed in DLBCL and MDS. These findings illustrate the clonal relationship between AITL and DLBCL in addition to AITL and MDS, with the latter being increasingly reported. The present findings strongly support the theory of multistep and multilineage tumorigenesis from a common founder clone.

Association between the pharmacokinetics of rabbit anti-thymocyte globulin and acute graft-versus-host disease in patients who received haploidentical hematopoietic stem cell transplantation.

Anti-thymocyte globulin (ATG) is an important prophylactic drug against acute graft-versus-host disease (aGVHD) after haploidentical hematopoietic stem cell transplantation (haplo-HSCT). This study analyzed the pharmacokinetics of rabbit ATG 2.5 mg/kg and its effect against aGVHD in 24 patients undergoing unmanipulated haplo-HSCT. All patients had hematological malignancies not in remission. The median absolute lymphocyte count (ALC) before rabbit ATG administration was 9.5/µL (range 0-41/µL). The grade ≥ II aGVHD group had a significantly lower median rabbit ATG concentration on days 0 (C0) and 7 (C7) and areas under the curve on days 0-7 (AUC0-7) and 0-32 (AUC0-32) than the grade 0-I aGVHD group. Among the four parameters, C0 was the most optimal for predicting aGVHD according to the receiver-operating characteristic (ROC) analysis (area under the ROC curve 0.893; 95% confidence interval 0.738-1.000). The high C0 (≥ 27.8 µg/mL) group had significantly lower cumulative incidence of grade ≥ II aGVHD on day 100 than the low C0 (< 27.8 µg/mL) group (13.8% vs. 88.9%, p < 0.001). In haplo-HSCT, the C0 of rabbit ATG is a good predictor of grade ≥ II aGVHD, even though ALC before rabbit ATG administration is not a predictor of aGVHD.

An Open-Label, Single-Arm, Multicenter Study of Ibrutinib in Japanese Patients With Steroid-dependent/Refractory Chronic Graft-Versus-Host Disease.

Chronic graft-versus-host disease (cGVHD) is a serious complication after allogeneic stem cell transplantation. There are no well-established treatment options for cGVHD after primary steroid-based treatment. Ibrutinib showed clinical benefit with an acceptable safety profile in steroid-dependent/refractory cGVHD patients in a Phase 1b/2 study (PCYC-1129-CA, NCT02195869), with which it was approved in the United States for adult cGVHD patients after failure of ≥1 systemic treatments. This open-label, single-arm, multicenter study was conducted to evaluate the efficacy, safety, pharmacokinetics, and pharmacodynamics of ibrutinib in Japanese patients ≥12 years of age with steroid-dependent/refractory cGVHD (NCT03474679). Patients were assessed on the basis of the National Institutes of Health (NIH) Consensus Development Project Criteria for Clinical Trials in cGVHD (2014). All patients received ibrutinib at a dose of 420 mg orally once daily, with a dose reduction to 280 mg/d on the concomitant use of voriconazole. Nineteen patients, including 1 adolescent, were enrolled and treated with ibrutinib in the study. At the time of clinical data cutoff (when the last patient completed the efficacy assessment at week 37), 10 of 19 patients (52.6%) remained on treatment whereas 9 of 19 patients (47.4%) had discontinued ibrutinib. The median duration of ibrutinib treatment was 9.63 (range 0.6 to 16.7+) months. The best overall response rate was 73.7%, and the rate of sustained response for ≥20 weeks was 71.4% for the responders (52.6% of all patients). Responses were seen across all the involved organs for cGVHD. Median daily corticosteroid dose requirement decreased by 0.06 mg/kg/d from baseline to week 36, whereas an improvement in the Lee cGVHD Symptom Scale score was observed in 42.1% of patients. The most common treatment-emergent adverse events (TEAEs) were pneumonia and stomatitis (36.8% each), upper respiratory tract infection (31.6%), cellulitis and platelet count decreased (26.3% each), and nausea (21.1%). Furthermore, 11 of 19 patients (57.9%) were reported with ≥1 treatment-emergent serious adverse events; the most common being pneumonia (26.3%) and cellulitis (15.8%). In total, 4 of 19 patients (21.1%) died during the study, of which 3 of 19 patients (15.8%) had TEAEs leading to death whereas 1 patient died of peritonitis, which occurred >30 days after the last dose of ibrutinib. Treatment-emergent adverse events leading to ibrutinib discontinuation were reported in 3 of 19 patients (15.8%). Ibrutinib was rapidly absorbed with a median time to reach maximum plasma concentration (tmax) of ~4.0 hours. Steady-state exposures were ~3.0- and ~1.4-fold higher for the patients receiving fluconazole (n = 8) and voriconazole (n = 4) with ibrutinib, respectively, as compared with patients not receiving CYP3A inhibitors (n = 7). Mean Bruton's tyrosine kinase occupancy was 88.1% at 4 hours after dose on day 1, and occupancy levels were maintained throughout the assessment period, regardless of the ibrutinib daily dose. Ibrutinib showed a clinically meaningful response and an acceptable safety profile in Japanese patients with steroid-dependent/refractory cGVHD; the safety profile was consistent with the known safety profile of ibrutinib in adults and with that seen in cGVHD patients receiving concomitant steroid treatment. Overall, the results were generally consistent with findings observed in the PCYC-1129-CA study.

Feasibility of six cycles of lenalidomide-based triplet induction before stem cell collection for newly diagnosed transplant-eligible multiple myeloma.

OBJECTIVES: Achieving a deep response with induction therapy has a major impact on outcomes following autologous stem cell transplantation. Although longer and intensified induction therapy may provide better disease control, longer exposure to lenalidomide negatively affects stem cell yield. We examined the feasibility of 6 cycles of lenalidomide-based triplet induction therapy before stem cell collection in transplant-eligible multiple myeloma patients. METHODS: In this prospective study, patients received a combination of bortezomib, lenalidomide, and dexamethasone for 6 cycles. For patients who did not achieve a deep response after 3 cycles, bortezomib was substituted with carfilzomib for the last 2 cycles (5th and 6th courses). RESULTS: Although only half of the patients achieved a deep response after 3 cycles, all but 1 patient achieved a very good partial response (n = 4) or complete response (n = 5) after completing 6 cycles. Among 9 patients who received cyclophosphamide-based stem cell mobilization, 1 patient required a second mobilization that was successfully performed using plerixafor. After autologous transplantation, 7 patients showed complete response, including 5 with minimal residual disease-negative status. CONCLUSION: This study demonstrates that 6 cycles of lenalidomide-based induction therapy before stem cell collection are a feasible and promising approach for transplant-eligible newly diagnosed multiple myeloma patients.The study is registered at UMIN Clinical Trials Registry as UMIN000026936.Trial registration: UMIN Japan identifier: UMIN000026936.

Elevation of Early Plasma Biomarkers in Patients with Clinical Risk Factors Predicts Increased Nonrelapse Mortality after Allogeneic Hematopoietic Stem Cell Transplantation.

Early prediction of nonrelapse mortality (NRM) in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) based on the results of laboratory tests is challenging. Thus, there is a need to evaluate biomarkers for prediction of NRM, a major problem that offsets the advantages of allo-HSCT. We tested the validity and efficacy of 2 plasma biomarkers, ST2 and Reg3α, based on the Mount Sinai Acute GVHD International Consortium (MAGIC) algorithm, for early prediction of NRM in Japanese patients who underwent allo-HSCT. We conducted a multicenter retrospective study to analyze the clinical data of 112 patients with hematopoietic malignancies who underwent allo-HSCT. Patient blood samples on day 7 after allo-HSCT were obtained from 6 hospitals. The plasma concentrations of ST2 and Reg3α were used to calculate a 6-month NRM risk score. Based on the scores determined in this study, we identified 64 low-risk patients and 48 high-risk patients for the 6-month NRM. The cumulative incidence of 6-month NRM was 29.2% in the high-risk group and 10.9% in the low-risk group (P < .05). The cumulative incidence of relapse mortality was similar in the high-risk and low-risk patients. The biomarker score was predictive in patients with an unrelated donor, an HLA-mismatched donor, high/very high Disease Risk Index, and Hematopoietic Cell Transplantation Comorbidity Index ≥1. Multivariate analysis identified high biomarker probability as a significant predictor of NRM. The MAGIC algorithm based on blood samples obtained at 7 days after allo-HSCT can identify individuals at high risk for NRM among patients with clinical risk factors for NRM in a Japanese cohort.

A multicenter phase II study of intrabone single-unit cord blood transplantation without antithymocyte globulin.

To overcome the delayed or failed engraftment after unrelated cord blood transplantation (CBT), we conducted a multicenter phase II study of intrabone single-unit CBT without antithymocyte globulin (ATG) for adult patients with hematological malignancies (UMIN-CTR, UMIN000020997). Sixty-four patients received an intrabone injection of unwashed (n = 61) or washed (n = 3) cord blood after local anesthesia. All injection-related adverse events were mild and resolved spontaneously. Sixty-two patients were evaluable for the efficacy of intrabone CBT of serological HLA-A, -B, and -DR ≥ 4/6 matched cord blood with a median number of 2.57 × 107/kg cryopreserved total nucleated cells. The probability of survival with neutrophil engraftment on day 28 was 77.4% (95% confidence interval, 67.0-85.8%), which exceeded the threshold value. The cumulative incidences of neutrophils ≥ 0.5 × 109/L on day 60 was 80.6% (68.2-88.6%), with a median time to recovery of 21 days after transplantation. The cumulative incidences of platelets ≥ 20 × 109/L and platelets ≥ 50 × 109/L on day 100 were 75.8% (62.6-84.9%) and 72.6% (59.4-82.1%), respectively, with median time to platelets ≥ 20 × 109/L and platelets ≥ 50 × 109/L of 38 and 45 days after transplantation, respectively. The cumulative incidences of grade II-IV and III-IV acute graft-versus-host disease were 29.0% and 6.5%, respectively. All responded to steroid therapy, and secondary treatments were not required. The present study suggests the efficacy of intrabone single-unit CBT without ATG in terms of early engraftment and controllable acute graft-versus-host disease.

Allogeneic hematopoietic stem cell transplantation from a 2-HLA-haplotype-mismatched family donor for posttransplant relapse: a prospective phase I/II study.

HLA haploidentical hematopoietic stem cell transplantation (HSCT), i.e., HSCT from a 1-HLA-haplotype-mismatched family donor, has been successfully performed even as a second transplantation for posttransplant relapse. Is the haploidentical the limit of HLA mismatches in HSCT? In order to explore the possibility of HLA-mismatched HSCT from family donors beyond haploidentical relatives, we conducted a prospective phase I/II study of 2-HLA-haplotype-mismatched HSCT (2-haplo-mismatch HSCT). We enrolled 30 patients with posttransplant relapse (acute myeloid leukemia: 18, acute lymphoblastic leukemia: 11, non-Hodgkin lymphoma: 1). 2-haplo-mismatch HSCT was performed as the second to sixth transplantations. The donors were siblings (n = 12), cousins (n = 16), and second cousins (n = 2). The conditioning regimen consisted of fludarabine, cytarabine, melphalan, low-dose anti-thymocyte globulin, and 3 Gy of total body irradiation. Graft-versus-host disease (GVHD) prophylaxis consisted of tacrolimus, methylprednisolone, and mycophenolate mofetil. All patients achieved neutrophil engraftment, except for a case of early death. The cumulative incidences of grades II-IV and III-IV acute GVHD were 36.7% and 16.7%, respectively. The overall survival at 1 year, relapse, and non-relapse mortality rates was 30.1%, 38.9%, and 44.3%, respectively. Considering the poor prognosis of posttransplant relapse, 2-haplo-mismatch HSCT can be an alternative option in a second or third transplantation.

Hematopoietic stem cell transplantation for diffuse large B-cell lymphoma having 8q24/MYC rearrangement in Japan.

The prognosis of diffuse large B-cell lymphoma (DLBCL) having MYC rearrangement (MYC-R), including double hit lymphoma (DHL), is poor by standard immunochemotherapy. To evaluate the significance of hematopoietic stem cell transplantation (SCT) for DLBCL with MYC-R, we retrospectively analyzed Japanese SCT registry data. In total, 54 patients with DLBCL with MYC-R were identified from 4336 registered adult DLBCL patients. Detailed clinical and cytogenetic information was obtained for 48 patients. The median age at diagnosis of the 48 patients was 54.5 (range 21-67) years. Twenty-six (54%) patients had MYC-R only (single hit), and 22 (46%) had MYC-R and BCL2, and/or BCL6 rearrangement (double/triple hit). In 12 patients who received auto-SCT during the first complete response (CR), both the 2-year overall survival (OS) and progression-free survival (PFS) rates were 75.0% (95% confidence interval [CI], 40.8%-91.2%). In 20 patients who received auto-SCT after relapsed or refractory state, the 2-year OS and PFS rates were 68.2% (95% CI, 41.9%-84.5%) and 59.6% (95% CI, 35.1%-77.4%), respectively. In 17 patients who received allo-SCT, only 4 patients underwent SCT in CR. The 2-year OS and PFS rates were 29.4% (95% CI, 10.7%-51.1%) and 17.6% (95% CI, 4.3%-38.3%), respectively. The rate of non-relapse mortality at 1 year was 41.2% (95% CI, 17.1%-64.0%) in this group. The outcomes of single hit and double or triple hit were not different. These findings suggest that auto-SCT may be effective for MYC-R DLBCL, including DHL patients of chemosensitive relapsed or refractory state. Since most patients received allo-SCT not in CR, the outcome of allo-SCT was unsatisfactory due to high non-relapse mortality and early relapse. To clarify the role of allo-SCT for MYC-R DLBCL, further accumulation of patients is necessary.

Treatment-free remission after first-line dasatinib discontinuation in patients with chronic myeloid leukaemia (first-line DADI trial): a single-arm, multicentre, phase 2 trial.

BACKGROUND: A previous dasatinib discontinuation (DADI) trial showed that 31 (49%) of 63 patients with chronic-phase chronic myeloid leukaemia who were treated with second-line or subsequent dasatinib could discontinue the drug safely. However, the safety and efficacy of discontinuing first-line dasatinib remains unclear. In this trial (the first-line DADI trial) we aimed to assess molecular relapse-free survival at 6 months after discontinuation of dasatinib in patients with chronic myeloid leukaemia who had been treated with first-line dasatinib and had maintained deep molecular response for at least 1 year. METHODS: The first-line DADI trial was a single-arm, multicentre, phase 2 trial done at 23 hospitals in Japan. Patients with newly diagnosed chronic-phase chronic myeloid leukaemia without hepatosplenomegaly and extramedullary mass, who received at least 24-month dasatinib treatment and had a sustained deep molecular response (defined as BCR-ABL1/ABL1 international scale ≤0·0069% in at least four successive samples spanning a 12 month period) were enrolled. Other eligibility criteria were an age of 15 years or older, an Eastern Cooperative Oncology Group performance status score of 0-2, and no primary organ dysfunction. The primary outcome was molecular relapse-free survival (also known as treatment-free remission) after discontinuation of dasatinib at 6 months and was analysed in all patients who completed the 12-month consolidation phase. Safety was assessed in all patients who received treatment. This study closed early due to accrual and is registered with the UMIN Clinical Trials Registry (UMIN000011099). FINDINGS: Between Sept 20, 2013 and July 12, 2016, 68 patients who had a deep molecular response after receiving first-line dasatinib for at least 24 months were enrolled and assigned to the consolidation phase. Nine patients were excluded during the consolidation phase and one patient was excluded after study completion because of meeting exclusion criteria. 58 patients discontinued dasatinib and were assessed. 32 (55%) of 58 patients had treatment-free remission at 6 months after dasatinib discontinuation, and median follow-up was 23·3 months (IQR 11·7-31·0). Treatment-free remission at 6 months was 55·2% (95% CI 43·7-69·6). No non-haematological adverse events worse than grade 2 occurred before dasatinib discontinuation. The most common haematological adverse event was anaemia (14 [21%] of 68 treated patients); three (4%) of 68 treated patients had grade 3 neutropenia and one (1%) had grade 4 lymphopenia. INTERPRETATION: Our findings suggest that dasatinib could be safely discontinued after first-line treatment in patients with chronic myeloid leukaemia who had received at least 36 months of therapy and sustained deep molecular response; however, further confirmation in larger trials is needed. FUNDING: Epidemiological and Clinical Research Information Network.

Predictive value of interim FDG-PET/CT findings in patients with diffuse large B-cell lymphoma treated with R-CHOP.

Objectives: To examine the prognostic value of interim 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) findings after 2-4 cycles of rituximab, plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) in patients with diffuse large B-cell lymphoma (DLBCL) receiving standardized treatment. Results: After a median 3.36 years (range 0.33 to 9.14 years), 24 of the 80 patients had documented relapse. In Interim-PET findings, 2-year PFS was significantly shorter for PET-positive as compared with PET-negative patients (50.0% vs. 86.4%; p = 0.0012). In End-PET findings, 2-year PFS was significantly shorter for PET-positive as compared with PET-negative patients (25.0% vs. 84.7%; p < 0.0001). The positive predictive value (PPV) and negative predictive value (NPV) of Interim-PET for predicting relapse or disease progression were 57.1% and 75.8%, respectively, while those for End-PET were 75.0% and 75.0%, respectively. Methods: Eighty DLBCL patients treated with first-line 6-8 R-CHOP courses regardless of interim imaging findings were enrolled. Each underwent FDG-PET/CT scanning at staging, and again during (Interim-PET) and at the end of (End-PET) therapy. PET positivity or negativity at Interim-PET and End-PET as related to progression-free survival (PFS) was examined using Kaplan-Meier analysis. Conclusion: Mid-treatment FDG-PET/CT findings may be useful for determining disease status in patients with DLBCL undergoing induction R-CHOP chemotherapy, though are not recommended for treatment decisions as part of routine clinical practice.

Safety and efficacy of amnion-derived mesenchymal stem cells (AM01) in patients with steroid-refractory acute graft-versus-host disease after allogeneic haematopoietic stem cell transplantation: a study protocol for a phase I/II Japanese trial.

INTRODUCTION: Regenerative medicine and cell therapies have been gaining much attention among clinicians. Therapeutic infusion of mesenchymal stromal cells (MSCs) is now a leading investigational strategy for the treatment of acute graft-versus-host disease (aGVHD). Bone marrow MSCs are approved for manufacture and marketing as a cell therapy for aGVHD. Our non-clinical studies confirmed that human amnion-derived MSCs had immunomodulatory activity equal to or higher than that of human bone marrow MSCs. This study will aim to evaluate the safety and efficacy of amnion-derived MSCs (AM01) in patients with steroid-refractory aGVHD. METHODS AND ANALYSIS: This study will be a multicentre, single-arm, open-label trial (an interventional study). This clinical trial will begin with a low-dose group, and when safety has been confirmed in at least three cases in the low-dose group, treatment will begin for the high-dose group, for which the safety will also be verified. The primary endpoint is to assess the safety of intravenous infusion therapy of AM01 within 24 hours after intravenous infusion of AM01. The secondary endpoint is to explore the efficacy of intravenous infusion therapy with AM01. ETHICS AND DISSEMINATION: The institutional review boards of all participating hospitals approved this study protocol (latest V3.3.0, 3 August 2018). Final data will be publicly announced. A report releasing the study results will be submitted for publication to an appropriate peer-reviewed journal. TRIAL REGISTRATION NUMBER: UMIN000029945.

Early evaluation of tumor response to 90Y-ibritumomab radioimmunotherapy in relapsed/refractory B cell non-Hodgkin lymphoma: what is the optimal timing for FDG-PET/CT?

PURPOSE: To determine the earliest optimal timing for assessment of early response following radioimmunotherapy in non-Hodgkin lymphoma patients using FDG-PET/CT. METHODS: FDG-PET/CT was performed prior to treatment (PET1), at 2 (PET2) weeks, and at 6 (PET3) weeks after 90Y-ibritumomab radioimmunotherapy in 55 patients. Response was evaluated based on the Deauville 5-point scale and Lugano criteria as well as semiquantitative analysis and compared with progression-free survival (PFS). RESULTS: PET 2 showed complete metabolic response (CMR), partial metabolic response (PMR), stable metabolic disease (SMD), and progressive metabolic disease (PMD) in 33, 13, 6, and 3 patients, respectively, while PET 3 in 41, 8, 3, and 3 patients, respectively. Mean SUVmax of 168 target lesions decreased over time (PET1, 2, 3; 5.58 ± 2.58, 1.87 ± 1.78, 1.75 ± 2.25, respectively). Progression or recurrence after a median of 12.6 months (range 2.6-72.0 months) was seen in 44 patients. Patients with CMR or metabolic response (CMR + PMR) on PET2 showed significantly longer PFS as compared to those who did not (p = 0.00028 and p = 0.029, respectively). A similar significant difference was observed based on PET3 (p = 0.00013 and p = 0.017, respectively). The same trend was observed when analyzing only the subgroup of patients with follicular lymphoma (N = 43/55) (p < 0.0001). CONCLUSION: Use of FDG-PET/CT findings with Lugano criteria for assessing early response to radioimmunotherapy after 6 weeks allowed for accurate evaluation and prognostic stratification, though scanning after 2 weeks was too soon to precisely evaluate response. KEY POINTS: • The optimal timing of FDG-PET/CT to obtain a suitable tool for assessment of response after 90 Y-ibritumomab radioimmunotherapy of lymphoma has not yet been defined. • Assessment after 6 weeks by FDG-PET/CT using the Lugano criteria accurately evaluates treatment response and prognosis. • FDG-PET/CT performed 2 weeks after radioimmunotherapy is too early as it significantly misses objective responses.

Low incidence of HHV-6 reactivation in haploidentical hematopoietic stem cell transplantation with corticosteroid as graft-vs-host disease prophylaxis compared with cord blood transplantation.

BACKGROUND: Human leukocyte antigen (HLA) mismatch and the administration of immunosuppressive agents are considered risks for human herpesvirus 6 (HHV-6) reactivation after stem cell transplantation (SCT). However, the incidence of HHV-6 reactivation in HLA-mismatched related SCT remains unknown. METHODS: We monitored plasma HHV-6 DNA loads weekly using real-time quantitative polymerase chain reaction for 5 weeks after SCT and compared serum IL-6 levels in HLA-mismatched SCT groups. RESULTS: Compared with detection in all 11 umbilical cord blood transplantation (CBT) patients (100%), plasma HHV-6 DNA was detected in only 3 of 42 haplo-SCT patients (7.1%) despite the use of methylprednisolone and antithymocyte globulin as graft-vs-host disease prophylaxis and a reduced-intensity conditioning regimen, respectively. Correspondingly, serum IL-6 levels in haplo-SCT patients were significantly lower than those in CBT patients. No HHV-6-associated encephalitis developed in either groups. CONCLUSIONS: Neither HLA disparity nor the use of methylprednisolone and antithymocyte globulin were risk factors for HHV-6 reactivation in our haplo-SCT patients. Rather than increasing risk, the administration of immunosuppressive agents potentially prevented HHV-6 reactivation after haplo-SCT by suppressing IL-6 production.