Disease-specific impact of anti-thymocyte globulin in allogeneic hematopoietic cell transplantation: a nationwide retrospective study on behalf of the JSTCT, transplant complications working group

The disease-specific impact of anti-thymocyte globulin (ATG) in allogeneic hematopoietic cell transplantation (allo-HCT) has not been determined. We retrospectively assessed the impact of ATG in allo-HCT using nationwide registry data from the Japan Society for Transplantation and Cellular Therapy. We included patients who received their first allo-HCT between 2007 and 2018 for acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), or malignant lymphoma (ML). In total, 8747 patients were included: 7635 patients did not receive ATG and 1112 patients received ATG as GVHD prophylaxis. The median follow-up period of surviving patients was 1457 days. There was no significant impact of pretransplant ATG on the OS or NRM rates in patients with ALL, AML, or ML. In patients with MDS, the probability of 3-year OS was 53.3% in the non-ATG group and 64.2% in the ATG group (P = 0.001). The cumulative incidence rates of relapse and NRM at 3 years were 14.2% and 30.3% (95% CI 27.2-33.3%), respectively, in the non-ATG group and 17.1% and 18.1% in the ATG group (P = 0.15 and P < 0.001). The same finding was observed in a propensity-score matched cohort. Our study suggests that the clinical benefit of ATG could vary among hematological diseases.

Risk and predictive factors for candidemia after allogeneic hematopoietic cell transplantation: JSTCT Transplant Complications Working Group

BACKGROUND

Although antifungal prophylaxis that covers Candida species is a standard of care in allogeneic hematopoietic cell transplantation (HCT), candidemia mainly caused by non-albicans Candida species still occurs and is associated with a high mortality rate.

OBJECTIVE

This study aimed to evaluate the risk factors for candidemia after allogeneic HCT. Particularly, we evaluated the impact of patient factors such as hematopoietic cell transplantation-specific comorbidity index (HCT-CI) and performance status (PS) in addition to well-recognized risk factors including donor type, delayed engraftment and graft-versus-host disease (GVHD).

STUDY DESIGN

By using data from a Japanese transplant registry database, we analyzed 26,236 pediatric and adult patients with hematological malignancies who underwent their first allogeneic HCT. The posttransplant period was divided into early (days 0-40), late (days 41-100) and very late (days 101-365) phases RESULTS: The 1-year cumulative incidence of candidemia was 1.8%. When we analyzed pretransplant factors, age ≥ 40 years (hazard ratio [HR] 1.85), male (HR 1.34), HCT-CI (HCT-CI 1-2, HR 1.56; HCT-CI ≥ 3, HR 2.21), PS ≥ 2 (HR 2.01), high-risk disease (HR 1.78) and donor type including HLA-mismatched related donor (MMRD) (HR 1.96), HLA-mismatched unrelated donor (HR 2.05) and cord blood (CB) (HR 2.85) were significantly associated with an increased incidence of candidemia. Focusing on the early phase (days 0-40), HCT-CI, PS, high-risk disease and CB transplantation together with engraftment and severe acute GVHD significantly affected the development of candidemia. In the late phase (days 41-100), higher HCT-CI, male, and donor type including MMRD, and CB were associated with the occurrence of candidemia together with acute GVHD and disease relapse. In the very late phase (days 101-365), HCT-CI ≥ 3 and high-risk disease significantly affected the occurrence of candidemia together with acute and chronic GVHD, and disease relapse.

CONCLUSIONS

In addition to well-recognized risk factors including donor type, engraftment and GVHD, patient factors such as HCT-CI and PS were associated with the development of candidemia, which suggests that severely ill patients with transplantation-associated complications are more likely to develop candidemia.

Anti-thymocyte globulin could potentially overcome an adverse effect of acute GVHD in matched-related PBSCT

BACKGROUND

Previous Japanese studies have shown that bone marrow transplantation (BMT) is associated with a better survival compared with peripheral blood stem cell transplantation (PBSCT) from matched related donors (MRDs). PBSCT recipients showed a higher incidence of severe graft-versus-host disease (GVHD) and non-relapse mortality (NRM) than BMT recipients. In recent years, the efficacy and safety of anti-thymocyte globulin (ATG) for PBSCT recipients has been reported from around the world.

OBJECTIVE

We aimed to compare BMT and PBSCT to identify current improvements and unmet needs among PBSCT recipients from MRDs. Moreover, we evaluated the impact of ATG administration on the outcomes for PBSCT recipients.

STUDY DESIGN

We retrospectively analyzed patients aged 16 years or older with acute leukemia, myelodysplastic syndrome, or chronic myeloid leukemia who received their first BMT or PBSCT from MRDs between 2009 and 2018 in Japan.

RESULTS

In total, 3599 transplantations were performed (BMT, 1218; PBSCT without ATG [PBSCT-ATG(-)], 2288; and PBSCT with ATG [PBSCT-ATG(+)], 93). The PBSCT-ATG(-) group had a higher NRM rate (hazard ratio [HR], 1.30; 95% confidence interval [CI], 1.08-1.57; p = 0.005) and lower overall survival (OS) rate (HR, 1.16; 95% CI, 1.04-1.30; p = 0.011) than the BMT group. Furthermore, the PBSCT-ATG(-) group had a higher incidence of grade III-IV, stage 2-4 gut, high-risk, and steroid-refractory acute GVHD than the BMT group. Acute GVHDs had a negative impact on NRM and OS rates. PBSCT-ATG(-) was also associated with a higher risk of chronic GVHD (HR: 1.89; 95% CI: 1.24-1.57; p < 0.001) and extensive chronic GVHD (HR: 1.44; 95% CI: 1.23-1.68; p < 0.001). The incidence of acute GVHD, chronic GVHD, and NRM and chronic GVHD-free relapse-free survival rates were comparable between the PBSCT-ATG(+) and BMT groups. The OS rate of patients with acute GVHD in the three donor groups was similar. Patients treated with reduced-intensity conditioning in the PBSCT-ATG(+) group had a higher relapse rate and lower OS rate than those in the BMT group.

CONCLUSIONS

In this Japanese cohort, standard calcineurin inhibitor-based GVHD prophylaxis was not sufficient for PBSCT recipients from MRDs because of the high incidence of severe acute GVHD. Moreover, prophylactic ATG was found to be a promising strategy against GVHD.

[Describing the Burdens on Patients and Healthcare Providers for Outpatient Chemotherapy-A Proceedings Paper]

Because the demand for outpatient chemotherapy has been increasing, the burdens on patients have recently become diversified, ranging from not only the physical burden due to hospital visits but also the psychological and financial burden due to the impact on employment. In addition, healthcare providers are currently facing a number of challenges in the management of outpatient chemotherapy, including labor shortages and equipment or system problems. On Tuesday, September 22,2020, an online meeting was held by the authors of this paper(moderator: Hiroko Bando)entitled" Describing the Burdens on Patients and Healthcare Providers for Outpatient Chemotherapy". This paper is the minutes of this conference and here we visualize the burdens on patients and healthcare providers and discuss the necessity of burden reduction or efficiency, measures to alleviate the burdens, and other topics.

Cytomegalovirus reactivation is associated with an increased risk of late-onset invasive aspergillosis independently of grade II-IV acute graft-versus-host disease in allogeneic hematopoietic stem cell transplantation: JSTCT Transplant Complications Working Group

There is a matter of debate about the clinical impact of cytomegalovirus (CMV) reactivation on the development of late-onset invasive aspergillosis (IA), which occurs 40 days or later after allogeneic hematopoietic stem cell transplantation (HSCT). Using a Japanese transplant registry database, we analyzed the risk factors for the development of late-onset IA in 21,015 patients who underwent their first allogeneic HSCT between 2006 and 2017. CMV reactivation was defined as the initiation of preemptive anti-CMV antiviral therapy. Overall, there were 582 cases of late-onset IA, which occurred at a median of 95 days after HSCT. The 2-year cumulative incidence was 3.4% (95% confidence interval (CI), 3.0-3.9) in patients with CMV reactivation within 40 days after HSCT and 2.5% (95% CI, 2.3-2.8) in those without it (P < 0.001). In a multivariate analysis, CMV reactivation as a time-dependent covariate was significantly associated with the development of late-onset IA (hazard ratio (HR) 1.40, P < 0.001), as well as grade II-IV acute GVHD, age > 50 and HCT-CI ≥ 3 in the entire cohort. If we focus on the subgroup without grade II-IV acute GVHD, which is generally an indication for systemic corticosteroid therapy (n = 12,622), CMV reactivation was still a significant factor for the development of late-onset IA (HR 1.37, P = 0.045) as well as age > 50 years, HCT-CI ≥ 3, and cord blood transplantation. In conclusion, CMV reactivation was associated with an increased risk of late-onset IA after allogeneic HSCT independently of acute GVHD. Close monitoring for late-onset IA is necessary for patients who develop CMV reactivation even without grade II-IV acute GVHD.

The differential effect of disease status at allogeneic hematopoietic cell transplantation on outcomes in acute myeloid and lymphoblastic leukemia

This study aimed to compare the effect of disease status at the time of allogeneic hematopoietic cell transplantation (HCT) on post-transplant outcomes between acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL). Japanese nationwide registry data for 6901 patients with AML and 2469 patients with ALL were analyzed. In this study, 2850 (41%), 937 (14%), 62 (1%), and 3052 (44%) AML patients and 1751 (71%), 265 (11%), 23 (1%), and 430 (17%) ALL patients underwent transplantation in first complete remission (CR1), second CR (CR2), third or subsequent CR (CR3 +), and non-CR, respectively. The probabilities of overall survival at 5 years for patients transplanted in CR1, CR2, CR3 + , and non-CR were 58%, 61%, 41%, and 26% for AML patients and 67%, 45%, 20%, and 21% for ALL patients, respectively. Multivariate analyses revealed that the risks of relapse and overall mortality were similar for AML patients transplanted in CR1 and CR2 (P = 0.672 and P = 0.703), whereas they were higher for ALL patients transplanted in CR2 than for those transplanted in CR1 (P < 0.001 for both). The risks of relapse and overall mortality for those transplanted in CR3 + and non-CR increased in a stepwise manner for both diseases, with the relevance being stronger for ALL than for AML patients. These results suggest a significant difference in the effect of disease status at HCT on post-transplant outcomes in AML and ALL. Further investigation to incorporate measurable residual disease data is warranted.

Difference in outcomes following allogeneic hematopoietic cell transplantation for patients with acute myeloid leukemia and myelodysplastic syndromes

To evaluate whether outcomes following allogeneic hematopoietic cell transplantation differ according to disease type, a three-way comparison for patients with de novo acute myeloid leukemia (AML) (n = 3318), AML evolving from myelodysplastic syndromes (MDS) (n = 208), and MDS with excess blasts (MDS-EB) (n = 994) was performed. The 5-year probabilities of overall survival (OS) for de novo AML, AML evolving from MDS, and MDS-EB were 60%, 42%, and 41% (p < 0.001), respectively. Multivariate analysis revealed that, compared to de novo AML, AML evolving from MDS was associated with a higher risk of NRM (p = 0.030) and MDS-EB with a higher risk of relapse (p < 0.001), both leading to lower OS (p = 0.010 and p < 0.001, respectively). These findings demonstrate inter-disease differences in post-transplant outcomes and highlight the needs to reduce NRM for AML evolving from MDS and to reduce relapse for MDS-EB.

Residual disease is a strong prognostic marker in patients with acute lymphoblastic leukaemia with chemotherapy-refractory or relapsed disease prior to allogeneic stem cell transplantation

Allogeneic haematopoietic stem cell transplantation (allo-HSCT) is one of the curative treatment options for acute lymphoblastic leukaemia (ALL). However, the outcomes in patients transplanted without complete remission (non-CR) have not yet been fully reported, and detailed analyses are required to identify subgroups in which optimal prognosis is expected and to optimize pre-transplant therapeutic strategies. Hence, we performed a multicentred retrospective cohort study including a total of 663 adult ALL patients transplanted at non-CR status; the median bone marrow (BM) blast counts at HSCT was 13·2%, and 203 patients (30·6%) were treated at primary induction failure status. The overall survival (OS) was 31·1% at two years, and the multivariate analyses identified five prognostic risk factors, including older age (≥50 years), increased BM blasts (≥10%), poor performance status, high haematopoietic cell transplantation (HCT)-comorbidity index, and relapsed disease status, among which BM blast was the most significantly related. A predictive scoring system composed of these risk factors clearly stratified OS (15·6-59·5% at two years). In conclusion, this is the first large-scale study to analyze the correlation of patient characteristics with post-transplant prognosis in ALL transplanted at non-CR status. The importance of blast control before HSCT should be focused on for better patient prognosis.

Differential Effect of Graft-versus-Host Disease on Survival in Acute Leukemia according to Donor Type

PURPOSE

The anti-leukemic activity of allogeneic hematopoietic cell transplantation (HCT) depends on both the intensity of conditioning regimen and the strength of the graft-versus-leukemia (GVL) effect. However, it is unclear whether the sensitivity of the GVL effects differs between donor type and graft source.

EXPERIMENTAL DESIGN

We retrospectively evaluated the effect of acute and chronic graft-versus-host disease (GVHD) on transplant outcomes for adults with acute leukemia (n = 6,548) between 2007 and 2017 using a Japanese database. In all analyses, we separately evaluated three distinct cohorts based on donor type [(8/8 allele-matched sibling donor, 8/8 allele-matched unrelated donor, and unrelated single-cord blood (UCB)].

RESULTS

The multivariate analysis, in which the development of GVHD was treated as a time-dependent covariate, showed a reductive effect of grade I-II acute GVHD on treatment failure (defined as 1-leukemia-free survival; P < 0.001), overall mortality (OM; P < 0.001), relapse (P < 0.001), and non-relapse mortality (NRM; P < 0.001) in patients receiving from UCB. A reductive effect of limited chronic GVHD on treatment failure (P < 0.001), OM (P < 0.001), and NRM (P < 0.001) was also shown in patients receiving from UCB. However, these effects were not always shown in patients receiving from other donors. The beneficial effects of mild acute and chronic GVHD after UCB transplantation on treatment failure were noted relatively in subgroups of patients with acute myelogenous leukemia and a non-remission status.

CONCLUSIONS

These data suggested that the development of mild GVHD could improve survival after UCB transplantation for acute leukemia.

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 (t_max) 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.

Single Cord Blood Transplantation Versus Unmanipulated Haploidentical Transplantation for Adults with Acute Myeloid Leukemia in Complete Remission

Allogeneic hematopoietic cell transplantation (HCT) is a potentially curative post-remission therapy for adult patients with acute myeloid leukemia (AML) in complete remission (CR). The availability of alternative human leukocyte antigen (HLA)-mismatched donors, such as cord blood and haploidentical related donors, could allow patients to receive allogeneic HCT who are without an HLA-matched sibling or unrelated donor. The use of these alternative donors is preferable for patients with advanced disease due to the rapid availability. However, comparative data for cord blood transplantation (CBT) and haploidentical related donor transplantation (haplo-HCT) are limited for adult patients with AML in CR. We sought to compare overall survival (OS); leukemia-free survival (LFS); graft-versus-host disease (GVHD)-free, relapse-free survival (GRFS); and chronic GVHD-free, relapse-free survival (CRFS) between single-unit CBT (SCBT) and haplo-HCT recipients for adult patients with intermediate- or poor-risk AML in CR. We retrospectively analyzed and compared the results of allogeneic hematopoietic cell transplantation in 1313 adult patients with intermediate- or poor-risk AML in CR who received either SCBT (n = 1102) or unmanipulated haplo-HCT (n = 211) between 2007 and 2018 in Japan. Among the whole cohort, the cumulative incidences of neutrophil and platelet recovery were significantly lower in SCBT recipients compared with those in haplo-HCT recipients (P < .001 for neutrophil, P < .001 for platelet). SCBT was significantly associated with a higher incidence of grade II to IV acute GVHD and lower incidence of extensive chronic GVHD compared to haplo-HCT (P = .013 for grades II to IV acute GVHD; P = .006 for extensive chronic GVHD). Haplo-HCT recipients developed a higher incidence of cytomegalovirus (CMV) antigenemia compared to SCBT recipients (P = .004). In the multivariate analysis, there were no significant differences for grades III or IV acute GVHD (hazard ratio [HR], 1.17; 95% confidence interval [CI], .88 to 1.57; P = .26), relapse incidence (HR, 1.09; 95% CI, .76 to 1.58; P = .61), non-relapse mortality (HR, .83; 95% CI, .58 to 1.18; P = .32), OS (HR, .92; 95% CI, .70 to 1.20; P = .56), LFS (HR, .94; 95% CI, .73 to 1.21; P = .67), GRFS (HR, 1.12; 95% CI, .90 to 1.40; P = .27), or CRFS (HR, 1.15; 95% CI, .92 to 1.44; P = .19) between the two donor types. In the propensity score matching analysis, which identified 180 patients in each cohort, there were no significant differences in transplant outcomes between the two donor types, except for delayed neutrophil (P < .001) and platelet recovery (P < .001) and a higher incidence of grades II to IV acute GVHD (P = .052) in SCBT. SCBT and unmanipulated haplo-HCT had similar survival outcomes for adult patients with AML in CR despite the lower hematopoietic recovery and higher grade II to IV acute GVHD in SCBT recipients and the higher CMV antigenemia in haplo-HCT recipients.

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.

Comparison of Transplantation Outcomes after Foscarnet and Ganciclovir Administration as First-Line Anti-Cytomegalovirus Preemptive Therapy

Ganciclovir (GCV) and foscarnet (FCN) are effective anti-cytomegalovirus (CMV) preemptive therapies; however, the impact of the 2 agents on various clinical outcomes of allogeneic hematopoietic stem cell transplantation (HSCT) remains unclear. We retrospectively analyzed data on 532 patients undergoing allogeneic HSCT from unrelated donors and administered FCN (n = 86) or GCV (n = 446) as first-line anti-CMV preemptive therapy. Overall survival, relapse, and nonrelapse mortality (NRM) did not differ between the FCN and GCV groups, whereas the GCV group had a higher risk of chronic graft-versus-host disease (cGVHD) (hazard ratio [HR], 2.38; 95% confidence interval [CI], 1.28 to 4.39; P = .006) and extensive cGVHD (HR, 3.94; 95% CI, 1.43 to 10.9; P = .008). All 13 patients with cGVHD in the FCN group survived. Switching to the other agent was done mainly due to hematologic adverse events in the GCV group and mainly due to insufficient efficacy in the FCN group. The incidence of end-organ CMV disease was similar in the 2 groups. Selection of FCN or GCV as first-line preemptive anti-CMV therapy did not affect survival, relapse, or NRM. Physicians can select either of the agents, depending on the clinical situation; however, the selection may influence the cGVHD-related clinical course in HSCT recipients.

Efficacy and safety of romiplostim in refractory aplastic anaemia: a Phase II/III, multicentre, open-label study

A previous dose-finding study has suggested that romiplostim is effective in patients with refractory aplastic anaemia (AA) and 10 µg/kg once weekly was recommended as a starting dose. In this Phase II/III, multicentre, open-label study, romiplostim was administered subcutaneously at a fixed dose of 10 µg/kg once weekly for 4 weeks (weeks 1-4) followed by weekly doses (5, 10, 15 and 20 µg/kg) titrated by platelet response for up to 52 weeks (weeks 5-52). A total of 31 patients with AA who were refractory to immunosuppressive therapy (IST) and thrombocytopenia (platelet count of ≤30 × 10⁹ /l) were enrolled. The primary efficacy endpoint of the proportion of patients achieving any haematological (platelet, neutrophil and erythrocyte) response at week 27 was 84% [95% confidence interval (CI) 66-95%]. Trilineage response was 39% (95% CI 22-58%) at week 53. The most common treatment-related adverse events (AEs) were headache and muscle spasms (each 13%). All AEs were mild or moderate except for three patients with Grade 3 hepatic AEs; no AEs necessitated romiplostim discontinuation. Two patients developed cytogenetic abnormalities, of whom one returned to normal karyotype at last follow-up. High-dose romiplostim is effective and well tolerated in the treatment of patients with AA refractory to IST.

The impacts of BCR-ABL1 mutations in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia who underwent allogeneic hematopoietic cell transplantation

The prognostic impacts of BCR-ABL1 fusion gene mutations in Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL) remain unknown. Using data from a nationwide Japanese registry, we have evaluated the prognostic impact of BCR-ABL1 mutations prior to the first allogeneic hematopoietic cell transplantation (HCT). The cohort included 289 patients with a median of 48 years of age (range: 16-70). Point mutations were detected in 110 patients. Of these, 90 (82%) harbored T315I mutations, while 20 had other mutations. With a median follow-up period of 29 months (range: 1-125), outcomes after 2 years were worse with mutations than without (overall survival [OS]: 34% vs 68%, p < 0.001; relapse rate [RR]: 48% vs 18%, p < 0.001), particularly with the presence of the T315I mutation (OS: 29% vs 68%, p < 0.001; RR: 54% vs 18%, p < 0.001). OS was significantly worse in the T315I group even among the cohort with hematological (p < 0.001) or molecular complete remission (p = 0.025) as compared to the no mutation group. Multivariate analysis determined the prognostic impact of the T315I mutation (OS: hazard ratio [HR] = 2.19, 95% confidence interval [CI]: 1.5-3.3, p < 0.001; RR: HR = 2.51, 95% CI: 1.5-4.2, p < 0.001). This study is the first to report on the prognostic significance of BCR-ABL1 mutations in Ph + ALL.

Updated Comparison of 7/8 HLA Allele-Matched Unrelated Bone Marrow Transplantation and Single-Unit Umbilical Cord Blood Transplantation as Alternative Donors in Adults with Acute Leukemia

The outcomes of 7/8 allele-matched unrelated bone marrow transplantation (7/8 UBMT) and umbilical cord blood transplantation (UCBT) have been improving. We retrospectively analyzed adults with acute leukemia who underwent their first 7/8 UBMT or UCBT in Japan. Between January 2008 and December 2017, a total of 4150 patients were recorded, including 488 who underwent 7/8 UBMT and 3662 who underwent UCBT. Only 32 patients with 7/8 UBMT had graft-versus-host-disease (GVHD) high-risk HLA mismatched pairs. Overall survival at 3 years was 54% for 7/8 the UBMT group and 46% for the UCBT group, a nonsignificant difference in multivariate analysis (hazard ratio [HR], 1.01; 95% confidence interval [CI], .88 to 1.17; P = .89). The 7/8 UBMT and UCBT groups showed a similar nonrelapse mortality rate (HR, 1.16; 95% CI, .96 to 1.45; P = .16) and relapse rate (HR, .85; 95% CI, .71 to 1.02; P = .08). However, the UCBT group had a lower risk of grade II-IV acute GVHD (HR, .76; 95% CI, .65 to .88; P < .001) and chronic GVHD (HR, .77; 95% CI, .66- .91; P = .002) compared with the 7/8 UBMT group. In stratified analyses combining disease risk with conditioning intensity, 7/8 UBMT showed superior overall survival to UCBT in standard risk and myeloablative conditioning (HR, .72; 95% CI, .56 to .93; P = .014). Both 7/8 UBMT and UCBT are appropriate alternative donor procedures. The stem cell source can be selected on the basis of disease risk, patient tolerability, or concerns regarding GVHD.

Ultra-high sensitivity HBsAg assay can diagnose HBV reactivation following rituximab-based therapy in patients with lymphoma

BACKGROUND & AIMS

HBV reactivation is a risk in patients receiving anti-CD20 antibodies for the treatment of lymphoma. The purpose of this post hoc analysis was to evaluate the efficacy of an ultra-high sensitivity HBsAg assay to guide preemptive antiviral treatment in patients with lymphoma and resolved HBV infections using prospectively stored samples from an HBV DNA monitoring study.

METHODS

HBV reactivation (defined as HBV DNA levels of ≥11 IU/ml) was confirmed in 22 of 252 patients. A conventional HBsAg assay (ARCHITECT, cut-off value: 0.05 IU/ml) and an ultra-high sensitivity HBsAg assay employing a semi-automated immune complex transfer chemiluminescence enzyme technique (ICT-CLEIA, cut-off value: 0.0005 IU/ml) were performed at baseline, at confirmed HBV reactivation and monitored after HBV reactivation.

RESULTS

Baseline HBsAg was detected using ICT-CLEIA in 4 patients; in all of whom precore mutants with high replication capacity were reactivated. Of the 6 patients with HBV DNA detected below the level of quantification at baseline, 5 showed HBV reactivation and 3 of the 5 had precore mutations. Sensitivity for detection by ARCHITECT and ICT-CLEIA HBsAg assays at HBV reactivation or the next sampling after HBV reactivation was 18.2% (4 of 22) and 77.3% (17 of 22), respectively. Of the 5 patients undetectable by ICT-CLEIA, HBV reactivation resolved spontaneously in 2 patients. All 6 patients reactivated with precore mutations including preS deletion could be diagnosed by ICT-CLEIA HBsAg assay at an early stage of HBV reactivation. Multivariate analysis showed that an anti-HBs titer of less than 10 mIU/ml, HBV DNA detected but below the level of quantification, and HBsAg detected by ICT-CLEIA at baseline were independent risk factors for HBV reactivation (adjusted hazard ratios, 15.4, 31.2 and 8.7, respectively; p <0.05).

CONCLUSIONS

A novel ICT-CLEIA HBsAg assay is an alternative method to diagnose HBV reactivation.

CLINICAL TRIAL NUMBER

UMIN000001299.

LAY SUMMARY

Hepatitis B virus can be reactivated in lymphoma patients receiving anti-CD20 antibodies such as rituximab. Currently, reactivation requires the monitoring of HBV DNA, but monitoring of the surface antigen (HBsAg) could provide a relatively inexpensive, quick and easy alternative. We assessed the performance of an ultra-high sensitivity HBsAg assay and showed that it could be effective for the diagnosis and monitoring of HBV reactivation.

Allogeneic hematopoietic stem cell transplantation at the first remission for younger adults with FLT3-internal tandem duplication AML: The JALSG AML209-FLT3-SCT study

In this phase II multicenter study (JALSG AML209-FLT3-SCT), we aimed to prospectively elucidate the role of allogeneic hematopoietic stem cell transplantation (allo-HSCT) at first complete remission (CR1) for FLT3-internal tandem duplication (ITD)-positive AML. Newly diagnosed de novo AML patients with FLT3-ITD were enrolled at the achievement of CR1 and received allo-HSCT as soon as possible after the first consolidation therapy. Mutations of 57 genes in AML cells at diagnosis were also analyzed. Among 48 eligible patients with a median age of 38.5 (17-49) years, 36 (75%) received allo-HSCT at a median of 108 days after CR1. The median follow-up was 1726 days. The primary end-point, 3-year disease-free survival (DFS) based on an intent to treat analysis, was 43.8% (95% confidence interval [CI], 30%-57%), suggesting the efficacy of this treatment because the lower limit of the 95% CI exceeded the threshold response rate of 20%. The 3-year overall survival, post-transplant DFS, and non-relapse mortality rates were 54.2% (95% CI, 39%-67%), 58.3% (95% CI, 41%-72%), and 25.0% (95% CI, 12%-40%), respectively. The median ITD allelic ratio (AR) was 0.344 (0.006-4.099). Neither FLT3-ITD AR nor cooccurring genetic alterations was associated with a poor DFS. This prospective study indicated the efficacy and safety of allo-HSCT for FLT3-ITD AML patients in CR1. This study was registered at: www.umin.ac.jp/ctr/ as #UMIN000003433.

Favorable Effect of Cytomegalovirus Reactivation on Outcomes in Cord Blood Transplant and Its Differences Among Disease Risk or Type

The effects of cytomegalovirus (CMV) reactivation on cord blood transplant (CBT) are unclear. We assessed the effect of CMV reactivation in adult single-unit CBT without in vivo T cell depletion. Of 3147 eligible cases, 2052 were acute myeloid leukemia (AML), 643 acute lymphoblastic leukemia (ALL), and 452 myelodysplastic syndrome (MDS). CMV reactivation up to 100 days after CBT was associated with better overall survival (OS) compared with no reactivation cases (57.3% versus 52.6% at 3 years after CBT), whereas nonrelapse mortality (NRM) was increased in ALL (16.2% versus 8.9%) and standard disease risk (17.1% versus 10.6%, P = .014) by CMV reactivation. On multivariate analysis, CMV reactivation had favorable effects on relapse in MDS (hazard ratio [HR], .55; P = .044) and high disease risk (HR, .77; P = .047). In NRM, only standard-risk cases showed adverse effects of CMV reactivation (HR, 1.56; P = .026). OS was significantly improved with CMV reactivation in a subgroup of patients with AML (HR, .84; P = .044), MDS (HR, .68; P = .048), and high disease risk (HR, .81; P = .013). This favorable effect of CMV reactivation on OS in AML and high disease risk cases was maintained even after considering the effect of grades II to IV acute graft-versus-host disease. Thus, CMV reactivation might have beneficial or adverse effects on relapse, NRM, and OS, depending on the disease type or disease risk.

Prospective evaluation of alternative donor from unrelated donor and cord blood in adult acute leukemia and myelodysplastic syndrome

A prospectively registered observational study was conducted to assess the significance of allogeneic hematopoietic stem cell transplantation from highly HLA-matched unrelated donors (UD) and cord blood (CB) on outcomes in adult acute leukemia (AL) and myelodysplastic syndrome (MDS). Between 2007 and 2015, 231 transplant-eligible patients were registered for a phase 2 study of alternative donor transplantation. After registration, a sufficient time period was given to find appropriate UD. Patients received CB transplantation (CBT) if an appropriate UD was unavailable. In total, 119 patients received CBT (106 AL and 13 MDS) and 91 patients received UD transplantation (UDT) (86 AL and 5 MDS). The median age was 39 years in both groups. The primary objective was overall survival (OS); secondary objectives included cumulative incidences of non-relapse mortality (NRM) and relapse, and disease-free survival. Diagnosis, disease status at transplantation, refined disease risk index, and hematopoietic cell transplant-specific comorbidity index did not differ between UDT and CBT. In multivariate analyses, graft source was not a significant risk factor for all objectives. In adjusted analyses, UDT and CBT showed similar OS, NRM, and relapse in this prospective study. CB can be a comparable alternative stem cell source to UD by achieving a timely transplant.

Late mortality and causes of death among long-term survivors after autologous hematopoietic stem cell transplantation

By evaluating risks of late mortality and causes of death among long-term survivors after autologous hematopoietic stem cell transplantation (HSCT) in Japan, we clarified what we should focus on during follow-up to reduce them. The study cohort included 6,780 patients who had survived for ≥2 years after the first autologous HSCT performed from 1974 to 2012 for hematological diseases. With a median follow-up of 6.0 years among survivors, overall survival probabilities at 5 and 10 years after HSCT were 92% and 83%, respectively. Eight hundred thirty deaths occurred: 451, recurrent primary diseases; 87, subsequent solid cancers; 57, subsequent hematological malignancies; 55, infections; 41, respiratory diseases; 19, cardiovascular diseases; 15, liver diseases; 10, neurological diseases; and 7, kidney/genitourinary diseases (Except small numbers of other causes and missing). According to the log-rank test, the risk of overall mortality was remarkably increased among HSCT recipients compared with the that in the general Japanese population (observed/expected ratio [O/E]=5.4; 95% confidence interval [CI], 5.0-5.8). The risks of cause-specific mortality increased with infection (O/E=6.8; 95% CI, 5.1-8.8), subsequent solid cancers (O/E=1.4; 95% CI, 1.1-1.7), subsequent hematological malignancies (O/E=14.3; 95% CI, 10.8-18.5), kidney/genitourinary diseases (O/E=3.4; 95% CI, 1.4-7.1), respiratory disease (O/E=9.0; 95% CI, 6.5-1.2), and liver diseases (O/E=2.6; 95% CI, 1.4-4.2). Long-term survivors after autologous HSCT are at an increased risk of death due to secondary cancers, infections, and any organ diseases as well as recurrence compared to the general population. When monitoring these patients in the outpatient clinic, it is important for physicians to predict a change in the patient's condition and to start treatment earlier.

Allogeneic hematopoietic stem cell transplantation for adult patients with B-cell acute lymphoblastic leukemia harboring t(1;19)(q23;p13.3); comparison with normal karyotype

There are few reports on allogeneic hematopoietic stem cell transplantation (allo-HSCT) for adult B-cell acute lymphoblastic leukemia (B-ALL) harboring t(1;19)(q23;p13.3). We used nationwide registry data of Japan for 2003-2016 to evaluate transplant outcomes and clarified prognostic factors among adult allo-HSCT recipients with B-ALL harboring t(1;19)(q23;p13.3) (n = 125). Compared with cytogenetically normal (CN) B-ALL patients (n = 1057), their 3-year overall survival (OS) rates were comparable (55.4% for t(1;19) and 54.4% for CN; P = 0.76). Considering only patients in first complete hematological remission (CR1), the 3-year OS rates remained comparable (70.5% for t(1;19) and 67.8% for CN; P = 0.86). For t(1;19) patients in CR1, minimal residual disease (MRD) at transplantation was associated with relatively worse outcomes. The 3-year OS rates were 43.6% for patients with MRD and 77.4% for those without it (P = 0.016). The 3-year relapse rates were 54.5% for patients with MRD and 12.8% for those without it (P < 0.001). Multivariate analyses revealed that MRD at transplantation was a significant risk factor for OS and relapse. In the high-intensity chemotherapy era, t(1;19)(q23;p13.3) did not have a poorer posttransplant prognosis than the normal karyotype. However, even for patients in CR1, MRD at transplantation was associated with comparatively worse OS and higher relapse rates.