Midostaurin reduces relapse in FLT3-mutant acute myeloid leukemia: the Alliance CALGB 10603/RATIFY trial

The prospective randomized, placebo-controlled CALGB 10603/RATIFY trial (Alliance) demonstrated a statistically significant overall survival benefit from the addition of midostaurin to standard frontline chemotherapy in a genotypically-defined subgroup of 717 patients with FLT3-mutant acute myeloid leukemia (AML). The risk of death was reduced by 22% on the midostaurin-containing arm. In this post hoc analysis, we analyzed the cumulative incidence of relapse (CIR) on this study and also evaluated the impact of 12 4-week cycles of maintenance therapy. CIR analyses treated relapses and AML deaths as events, deaths from other causes as competing risks, and survivors in remission were censored. CIR was improved on the midostaurin arm (HR = 0.71 (95% CI, 0.54-0.93); p = 0.01), both overall and within European LeukemiaNet 2017 risk classification subsets when post-transplant events were considered in the analysis as events. However, when transplantation was considered as a competing risk, there was overall no significant difference between the risks of relapse on the two randomized arms. Patients still in remission after consolidation with high-dose cytarabine entered the maintenance phase, continuing with either midostaurin or placebo. Analyses were inconclusive in quantifying the impact of the maintenance phase on the overall outcome. In summary, midostaurin reduces the CIR.

One and a half million hematopoietic stem cell transplants: continuous and differential improvement in worldwide access with the use of non-identical family donors

The Worldwide Network of Blood and Marrow Transplantation (WBMT) pursues the mission of promoting hematopoietic cell transplantation (HCT) for instance by evaluating activities through member societies, national registries and individual centers. In 2016, 82,718 first HCTs were reported from 1662 HCT teams in 86 of the 195 World Health Organization member states representing a global increase of 6.2% in autologous and 7.0% in allogeneic HCT and bringing the total to 1,298,897 procedures. Assuming a frequency of 84,000/year, 1.5 million HCTs had been performed by 2019 from 1957. Slightly more autologous (53.5%) than allogeneic and more related (53.6%) than unrelated HCTs were reported. A remarkable increase was noted in haploidentical related HCT for leukemias and lymphoproliferative diseases, but even more in non-malignant diseases. Transplant rates (TR; HCT/10 million population) varied according to region reaching 560.8 in North America, 438.5 in Europe, 76.7 in Latin America, 53.6 in South East Asia/Western Pacific (SEA/WPR) and 27.8 in African/East Mediterranean (AFR/EMR). Interestingly, haploidentical TR amounted to 32% in SEA/WPR and 26% in Latin America, but only 14% in Europe and EMR and 4.9% in North America of all allogeneic HCT. HCT team density (teams/10 million population) was highest in Europe (7.7) followed by North America (6.0), SEA/WPR (1.9), Latin America (1.6) and AFR/EMR (0.4). HCTs are increasing steadily worldwide with narrowing gaps between regions and greater increase in allogeneic compared to autologous activity. While related HCT is rising, largely due to increase in haploidentical HCT, unrelated is plateauing and cord blood in decline.

One and a half million hematopoietic stem cell transplants: continuous and differential improvement in worldwide access with the use of non-identical family donors

The Worldwide Network of Blood and Marrow Transplantation (WBMT) pursues the mission of promoting hematopoietic cell transplantation (HCT) for instance by evaluating activities through member societies, national registries and individual centers. In 2016, 82,718 first HCT were reported by 1,662 HCT teams in 86 of the 195 World Health Organization member states representing a global increase of 6.2% in autologous HCT and 7.0% in allogeneic HCT and bringing the total to 1,298,897 procedures. Assuming a frequency of 84,000/year, 1.5 million HCT were performed by 2019 since 1957. Slightly more autologous (53.5%) than allogeneic and more related (53.6%) than unrelated HCT were reported. A remarkable increase was noted in haploidentical related HCT for leukemias and lymphoproliferative diseases, but even more in non-malignant diseases. Transplant rates (TR; HCT/10 million population) varied according to region reaching 560.8 in North America, 438.5 in Europe, 76.7 in Latin America, 53.6 in South East Asia/Western Pacific (SEA/WPR) and 27.8 in African/East Mediterranean (AFR/EMR). Interestingly, haploidentical TR amounted to 32% in SEA/WPR and 26% in Latin America, but only 14% in Europe and EMR and 4.9% in North America of all allogeneic HCT. HCT team density (teams/10 million population) was highest in Europe (7.7) followed by North America (6.0), SEA/WPR (1.9), Latin America (1.6) and AFR/EMR (0.4). HCT are increasing steadily worldwide with narrowing gaps between regions and greater increase in allogeneic compared to autologous activity. While related HCT is rising, largely due to increase in haploidentical HCT, unrelated HCT is plateauing and cord blood HCT is in decline.

Randomized, Single-Blind, Multicenter Phase II Study of Two Doses of Imetelstat in Relapsed or Refractory Myelofibrosis

PURPOSE

Patients with myelofibrosis who are relapsed or refractory (R/R) to Janus-associated kinase inhibitors (JAKis) have poor clinical outcomes including dismal overall survival (OS) that ranges between 13 and 16 months. Imetelstat, a telomerase inhibitor, was evaluated in patients with intermediate-2 or high-risk myelofibrosis R/R to JAKi in a phase II multicenter study (ClinicalTrials.gov identifier: NCT02426086).

PATIENTS AND METHODS

Patients were randomly assigned to receive either imetelstat 9.4 mg/kg or 4.7 mg/kg intravenous once every 3 weeks. Spleen response (≥ 35% spleen volume reduction) and symptom response (≥ 50% reduction in total symptom score) rates at week 24 were coprimary end points. Secondary end points included OS and safety.

RESULTS

Study enrollment was closed early, and patients treated with 4.7 mg/kg were permitted to continue treatment with 9.4 mg/kg. At week 24, spleen and symptom response rates were 10.2% and 32.2% in the 9.4-mg/kg arm and 0% and 6.3% in the 4.7-mg/kg arm. Treatment with imetelstat 9.4 mg/kg led to a median OS of 29.9 months and bone marrow fibrosis improvement in 40.5% and variant allele frequency reduction of driver mutations in 42.1% of evaluable patients. Fibrosis improvement and variant allele frequency reduction correlated with OS. Target inhibition was demonstrated by reduction of telomerase activity and human telomerase reverse transcriptase level and correlated with spleen response, symptom response, and OS. Most common adverse events on both arms were grade 3 or 4 reversible cytopenias.

CONCLUSION

In this phase II study of two imetelstat doses, 9.4 mg/kg once every 3 weeks demonstrated clinical benefits in symptom response rate, with an acceptable safety profile for this poor-risk JAKi R/R population. Biomarker and bone marrow fibrosis assessments suggested selective effects on the malignant clone. A confirmatory phase III study is currently underway.

Hotspot DNMT3A mutations in clonal hematopoiesis and acute myeloid leukemia sensitize cells to azacytidine via viral mimicry response

Somatic mutations in DNA methyltransferase 3A (DNMT3A) are among the most frequent alterations in clonal hematopoiesis (CH) and acute myeloid leukemia (AML), with a hotspot in exon 23 at arginine 882 (DNMT3A^R882). Here, we demonstrate that DNMT3A^R882H-dependent CH and AML cells are specifically susceptible to the hypomethylating agent azacytidine (AZA). Addition of AZA to chemotherapy prolonged AML survival solely in individuals with DNMT3A^R882 mutations, suggesting its potential as a predictive marker for AZA response. AML and CH mouse models confirmed AZA susceptibility specifically in DNMT3A^R882H-expressing cells. Hematopoietic stem cells (HSCs) and progenitor cells expressing DNMT3A^R882H exhibited cell autonomous viral mimicry response as a result of focal DNA hypomethylation at retrotransposon sequences. Administration of AZA boosted hypomethylation of retrotransposons specifically in DNMT3A^R882H-expressing cells and maintained elevated levels of canonical interferon-stimulated genes (ISGs), thus leading to suppressed protein translation and increased apoptosis.

ELN risk stratification and outcomes in secondary and therapy-related AML patients consolidated with allogeneic stem cell transplantation

Secondary or therapy-related acute myeloid leukemia (s/tAML) differs biologically from de novo disease. In general s/tAML patients have inferior outcomes after chemotherapy, compared to de novo cases and often receive allogeneic stem cell transplantation (HSCT) for consolidation. The European LeukemiaNet (ELN) risk stratification system is commonly applied in AML but the clinical significance is unknown in s/tAML. We analyzed 644 s/tAML or de novo AML patients receiving HSCT. s/tAML associated with older age and adverse risk, including higher ELN risk. Overall, s/tAML patients had similar cumulative incidence of relapse (CIR), but higher non-relapse mortality (NRM) and shorter overall survival (OS). In multivariate analyses, after adjustment for ELN risk and pre-HSCT measurable residual disease status, disease origin did not impact outcomes. Within the ELN favorable risk group, CIR was higher in s/tAML compared to de novo AML patients likely due to a different distribution of genetic aberrations, which did not translate into shorter OS. Within the ELN intermediate and adverse group outcomes were similar in de novo and s/tAML patients. Thus, not all s/tAML have a dismal prognosis and outcomes of s/tAML after allogeneic HSCT in remission are comparable to de novo patients when considering ELN risk.

Phase III, Randomized, Placebo-Controlled Trial of CC-486 (Oral Azacitidine) in Patients With Lower-Risk Myelodysplastic Syndromes

PURPOSE

Treatment options are limited for patients with lower-risk myelodysplastic syndromes (LR-MDS). This phase III, placebo-controlled trial evaluated CC-486 (oral azacitidine), a hypomethylating agent, in patients with International Prognostic Scoring System LR-MDS and RBC transfusion-dependent anemia and thrombocytopenia.

METHODS

Patients were randomly assigned 1:1 to CC-486 300-mg or placebo for 21 days/28-day cycle. The primary end point was RBC transfusion independence (TI).

RESULTS

Two hundred sixteen patients received CC-486 (n = 107) or placebo (n = 109). The median age was 74 years, median platelet count was 25 × 10⁹/L, and absolute neutrophil count was 1.3 × 10⁹/L. In the CC-486 and placebo arms, 31% and 11% of patients, respectively, achieved RBC-TI (P = .0002), with median durations of 11.1 and 5.0 months. Reductions of ≥ 4 RBC units were attained by 42.1% and 30.6% of patients, respectively, with median durations of 10.0 and 2.3 months, and more CC-486 patients had ≥ 1.5 g/dL hemoglobin increases from baseline (23.4% v 4.6%). Platelet hematologic improvement rate was higher with CC-486 (24.3% v 6.5%). Underpowered interim overall survival analysis showed no difference between CC-486 and placebo (median, 17.3 v 16.2 months; P = .96). Low-grade GI events were the most common adverse events in both arms. In the CC-486 and placebo arms, 90% and 73% of patients experienced a grade 3-4 adverse event. Overall death rate was similar between arms, but there was an imbalance in deaths during the first 56 days (CC-486, n = 16; placebo, n = 6), most related to infections; the median pretreatment absolute neutrophil count for the 16 CC-486 patients was 0.57 × 10⁹/L.

CONCLUSION

CC-486 significantly improved RBC-TI rate and induced durable bilineage improvements in patients with LR-MDS and high-risk disease features. More early deaths occurred in the CC-486 arm, most related to infections in patients with significant pretreatment neutropenia. Further evaluation of CC-486 in MDS is needed.

Changes in Hematopoietic Cell Transplantation Practices in Response to COVID-19: A Survey from the Worldwide Network for Blood & Marrow Transplantation

SARS-CoV-2 has spread rapidly worldwide, but the full impact of the COVID-19 pandemic on the field of hematopoietic cell transplantation (HCT) remains unknown. To understand this better, an 18-item online survey was disseminated by the Worldwide Network for Blood & Marrow Transplantation with questions exploring SARS-CoV-2 testing algorithms, mobilization, and cryopreservation strategies and COVID-19 infections in allogeneic related and autologous hematopoietic progenitor cell (HPC) donors. The aim of this survey was to assess the impact of the outbreak on policies relating to HPC mobilization, collection, and processing with respect to changes in daily routine. A total of 91 individual responses from distinct centers in 6 continents were available for analysis. In these centers, the majority (72%) of allogeneic related and autologous donors are routinely tested for SARS-CoV-2 before HPC collection, and 80% of centers implement cryopreservation of allogeneic HPC grafts before commencing conditioning regimens in patients. Five related and 14 autologous donors who tested positive for COVID-19 did not experience any unexpected adverse events or reactions during growth factor administration (eg, hyperinflammatory syndrome). These data are limited by the small number of survey respondents but nonetheless suggest that centers are following the recommendations of appropriate scientific organizations and provide some preliminary data to suggest areas of further study.

Addition of Rituximab in Reduced Intensity Conditioning Regimens for B-Cell Malignancies Does Not Influence Transplant Outcomes: EBMT Registry Analyses Following Allogeneic Stem Cell Transplantation for B-Cell Malignancies

Rituximab (R) is increasingly incorporated in reduced intensity conditioning (RIC) regimens for allogeneic hematopoietic cell transplantation (alloHCT) in patients with B-cell malignancies, not only to improve disease control, but also to prevent graft-versus-host disease (GVHD). There are no randomized prospective data to validate this practice, although single center data and the CIBMTR analysis have shown promising results. We aimed at validation of these findings in a large registry study. We conducted a retrospective analysis using the EBMT registry of 3,803 adult patients with B-cell malignancies undergoing alloHCT (2001-2013) with either rituximab (R-RIC-9%) or non-rituximab (RIC-91%) reduced intensity regimens respectively. Median age and median follow up were 55 years (range 19.1-77.3) and 43.2 months (range 0.3-179.8), respectively. There was no difference in transplant outcomes (R-RIC vs RIC), including 1-year overall survival (69.9% vs 70.7%), 1-year disease-free survival (64.4% vs 62.2%), 1-year non-relapse mortality (21% vs 22%), and day-100 incidence of acute GVHD 2-4° (12% vs 12%). In summary, we found that addition of rituximab in RIC regimens for B-cell malignancies had no significant impact on major transplant outcome variables. Of note, data on chronic GVHD was not available, limiting the conclusions that can be drawn from the present study.

Efficacy of Pazopanib With or Without Gemcitabine in Patients With Anthracycline- and/or Ifosfamide-Refractory Soft Tissue Sarcoma: Final Results of the PAPAGEMO Phase 2 Randomized Clinical Trial

Importance

Pazopanib and gemcitabine have shown good tolerability, albeit modest single-agent activity in pretreated soft tissue sarcoma. A combined regimen to improve outcomes is required.

Objective

To determine the efficacy of gemcitabine and pazopanib compared with pazopanib alone.

Design, Setting, and Participants

This multicenter, randomized phase 2 clinical trial was conducted in Germany from September 2011 to July 2014 and included patients with an Eastern Cooperative Oncology Group performance status score of 0 to 2, adequate organ function, measurable lesion, and progression after at least 1 prior treatment with anthracyclines and/or ifosfamide. Data analysis was performed during 2019 and 2020.

Interventions

Patients were randomized to pazopanib with gemcitabine (A) or without gemcitabine (B).

Main Outcomes and Measures

The primary end point was progression-free survival rate (PFSR) at 12 weeks; secondary end points included toxicity, quality of life, overall survival, and response rates.

Results

A total of 90 patients were randomized, and 86 eligible patients (43 women [50%]) were evaluable, with a median age of 57 (range, 22-84) years and Eastern Cooperative Oncology Group performance status score of 0/1 in 77 participants (90%). The predominant histological subtypes were leiomyosarcoma (22 [26%]) and liposarcoma (16 [19%]). After a median follow-up of 12.4 (range, 1-48) months, the primary end point was met, with a PFSR at 12 weeks of 74% (A) vs 47% (B) (hazard ratio [HR], 1.60; 90% CI, 1.15-2.23; P = .01). In the combination arm, PFSR was significantly longer, with a median of 5.6 vs 2.0 months (HR, 0.58; 95% CI, 0.36-0.92; P = .02) compared with single-agent pazopanib, whereas overall survival was similar, with 13.1 vs 11.2 months (HR, 0.98; 95% CI, 0.60-1.58; P = .83). The objective response rate was overall low, with 11% (A) vs 5% (B) (P = .10). The toxicity of the combination of pazopanib and gemcitabine was increased, but it was manageable and mainly hematological.

Conclusions and Relevance

This phase 2 randomized clinical trial of patients with soft tissue sarcoma found that the addition of gemcitabine to pazopanib was tolerable, and PFSR at 12 weeks was significantly higher compared with pazopanib alone. These results suggest clinical activity of the combination, but they should be confirmed in a phase 3 trial in a more homogeneous population (eg, leiomyosarcoma).

Trial Registration

German Clinical Trials Identifier: DRKS00003139.

Worldwide Network for Blood and Marrow Transplantation (WBMT) Recommendations Regarding Essential Medications Required To Establish An Early Stage Hematopoietic Cell Transplantation Program

Establishing a hematopoietic cell transplantation (HCT) program is complex. Planning is essential while establishing such a program to overcome the expected challenges. Authorities involved in HCT program establishment will need to coordinate the efforts between the different departments required to start up the program. One essential department is pharmacy and the medications required. To help facilitate this, the Worldwide Network for Blood and Marrow Transplantation organized a structured survey to address the essential medications required to start up an HCT program. A group of senior physicians and pharmacists prepared a list of the medications used at the different phases of transplantation. These drugs were then rated by a questionnaire using a scale of necessity based on the stage of development of the transplant program. The questionnaire was sent to 30 physicians, in different parts of the world, who have between 5 and 40 years of experience in autologous and/or allogeneic transplantation. This group of experts scored each medication on a 7-point scale, ranging from an absolute requirement (score of 1) to not required (score of 7). The results are presented here to help guide the prioritization of required medications.

Real-World Issues and Potential Solutions in Hematopoietic Cell Transplantation during the COVID-19 Pandemic: Perspectives from the Worldwide Network for Blood and Marrow Transplantation and Center for International Blood and Marrow Transplant Research Health Services and International Studies Committee

The current COVID-19 pandemic, caused by SARS-CoV-2, has impacted many facets of hematopoietic cell transplantation (HCT) in both developed and developing countries. Realizing the challenges as a result of this pandemic affecting the daily practice of the HCT centers and the recognition of the variability in practice worldwide, the Worldwide Network for Blood and Marrow Transplantation (WBMT) and the Center for International Blood and Marrow Transplant Research's (CIBMTR) Health Services and International Studies Committee have jointly produced an expert opinion statement as a general guide to deal with certain aspects of HCT, including diagnostics for SARS-CoV-2 in HCT recipient, pre- and post-HCT management, donor issues, medical tourism, and facilities management. During these crucial times, which may last for months or years, the HCT community must reorganize to proceed with transplantation activity in those patients who urgently require it, albeit with extreme caution. This shared knowledge may be of value to the HCT community in the absence of high-quality evidence-based medicine. © 2020 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Efficacy and Safety of ABP 798: Results from the JASMINE Trial in Patients with Follicular Lymphoma in Comparison with Rituximab Reference Product

Introduction

ABP 798 is being developed as a biosimilar to rituximab reference product (RP), a CD20-directed cytolytic antibody that is approved in the US and EU for the treatment of non-Hodgkin lymphoma (NHL).

Methods

This randomized, double-blind, comparative clinical study (JASMINE) evaluated the efficacy and safety of ABP 798 compared with rituximab RP. Adult, anti-CD20 treatment naïve patients diagnosed with grade 1, 2, or 3a follicular B-cell NHL expressing CD20 were randomized 1:1 to receive a 375 mg/m² infusion of either ABP 798 or rituximab RP once weekly for 4 weeks and at weeks 12 and 20. Tumor assessments were performed at baseline and weeks 12 and 28. Primary endpoint was the risk difference (RD) of overall response rate (ORR) of complete response, unconfirmed complete response, or partial response by week 28 based on data from central, independent, and blinded assessments of disease.

Results

Of the 256 randomized patients, 254 were treated with ABP 798 (n = 128; 100%) or rituximab RP (n = 126; 98.4%); 96 (78.0%) patients in the ABP 798 group and 87 (70.2%) in the rituximab RP group had a best ORR by week 28. The point estimate of RD in ORR between ABP 798 and rituximab RP from the adjusted generalized linear model for stratification factors was 7.7%. Clinical equivalence was based on sequential testing of the one-sided 95% lower confidence limits and one-sided 95% upper confidence limits of RD in ORR (− 1.4% and 16.8%, respectively) which was within the prespecified non-inferiority margin (− 15%) and non-superiority margin (35.5%), respectively. Results of sensitivity analyses were consistent with the primary efficacy analysis. ABP 798 was also comparable to rituximab RP across additional secondary endpoints, further supporting the conclusion of similarity, and including: RD of ORR at week 12; trough serum concentrations; percent of patients with complete depletion of CD19+ cell count at day 8; safety; and immunogenicity.

Conclusions

These results support a conclusion of similar clinical efficacy between ABP 798 and rituximab RP in patients with follicular lymphoma.

NCT Number

NCT02747043; first posted April 21, 2016.

EudraCT Number

2013-005,542-11; submitted 14 October, 2014.

Impact of patient: donor HLA disparity on reduced-intensity-conditioned allogeneic stem cell transplants from HLA mismatched unrelated donors for AML: from the ALWP of the EBMT

Patients with acute myeloid leukaemia (AML) who lack a matched sibling or unrelated donor commonly undergo transplantation from a donor matched at 9/10 HLA-A, -B, -C, -DRB1, -DQB1 alleles, and it is unclear if a specific locus mismatch is preferable to any other. We therefore studied 937 patients with AML in complete remission transplanted using a reduced intensity conditioning regimen from an unrelated donor mismatched at a single allele. In a multivariate analysis, patient age, adverse karyotype and patient cytomegalovirus (CMV) seropositivity were correlated with decreased leukaemia free survival (LFS) and overall survival (OS). There was no significant difference in LFS or OS between patients transplanted from donors mismatched at HLA-A, -B, -C or -DRB1 in comparison to a HLA-DQB1 mismatched transplant. In a multivariate analysis, patients transplanted with a HLA-A mismatched donor had higher rates of acute graft-versus-host disease (GVHD) and non-relapse mortality (NRM) than patients transplanted with a HLA-DQB1 mismatched donor. Patient CMV seropositivity was associated with an increase in NRM and acute GVHD and reduced LFS and OS, regardless of donor CMV status. For CMV seropositive patients lacking a fully matched donor, alternative GVHD and CMV prophylaxis strategies should be considered.

Allogeneic stem cell transplantation mitigates the adverse prognostic impact of high diagnostic BAALC and MN1 expression in AML

For most acute myeloid leukemia (AML) patients, an allogeneic hematopoietic stem cell transplantation (HSCT) offers the highest chance of sustained remissions and long-term survival. At diagnosis, high expression of the AML-associated genes BAALC (brain and acute leukemia, cytoplasmic) and MN1 (meningioma-1) were repeatedly linked to inferior outcomes in patients consolidated with chemotherapy while data for patients receiving HSCT remain limited. Using clinically applicable digital droplet PCR assays, we analyzed the diagnostic BAALC/ABL1 and MN1/ABL1 copy numbers in 302 AML patients. High BAALC/ABL1 and MN1/ABL1 copy numbers associated with common adverse prognostic factors at diagnosis. However, while high diagnostic copy numbers of both genes associated with shorter event free survival (EFS) and overall survival (OS) in patients receiving chemotherapy, there was no prognostic impact in patients undergoing HSCT. Our data suggests that the adverse prognostic impact of high BAALC and MN1 expression are mitigated by allogeneic HSCT. But preHSCT BAALC/ABL1 and MN1/ABL1 assessed in remission prior to HSCT remained prognosticators for EFS and OS independent of the diagnostic expression status. Whether allogeneic HSCT may improve survival for AML patients with high diagnostic BAALC or MN1 expression should be investigated prospectively and may improve informed decisions towards individualized consolidation options in AML.

Association of Country-Specific Socioeconomic Factors With Survival of Patients Who Experience Severe Classic Acute Graft-vs.-Host Disease After Allogeneic Hematopoietic Cell Transplantation. An Analysis From the Transplant Complications Working Party of the EBMT

Acute graft-vs.-host disease (aGvHD) is one of the most frequent causes of transplant-related mortality (TRM) after allogeneic hematopoietic cell transplantation (alloHCT). Its treatment is complex and costly. The aim of this study was to retrospectively analyze the impact of country-specific socioeconomic factors on outcome of patients who experience severe aGvHD. Adults with hematological malignancies receiving alloHCT from either HLA-matched siblings (n = 1,328) or unrelated donors (n = 2,824) developing grade 3 or 4 aGvHD were included. In univariate analysis, the probability of TRM at 2 years was increased for countries with lower current Health Care Expenditure (HCE, p = 0.04), lower HCE as % of Gross Domestic Product per capita (p = 0.003) and lower values of the Human Development Index (p = 0.02). In a multivariate model, the risk of TRM was most strongly predicted by current HCE (HR = 0.76, p = 0.006). HCE >median was also associated with reduced risk of the overall mortality (HR 0.73, p = 0.0006) and reduced risk of treatment failure (either relapse or TRM; HR 0.77, p = 0.004). We conclude that country-specific socioeconomic factors, in particular current HCE, are strongly associated with survival of patients who experience severe aGvHD.

No advantage of Imatinib in combination with hydroxyurea over Imatinib monotherapy: a study of the East German Study Group (OSHO) and the German CML study group

INTRODUCTION

The combination of Imatinib (IM) and hydroxyurea (HU) was explored for the treatment of chronic myelogenous leukemia (CML).

METHOD

After in vitro testing and a phase I study (n = 20), 59 patients were randomized in the IM/HU and 29 in the IM arm. According to protocol, 49 propensity-score matched IM patients were included from the CML-IV study.

RESULTS

Additive specific inhibition of CML cells by IM/HU was detected in vitro. HU 500 mg qd in combination with IM 400 mg qd proved feasible in the phase I study. Overall, no significant difference with respect to major molecular response (MMR) at 18 months (IM/HU and IM 66%; primary endpoint) was observed. Significant differences were noted for MMR at 6 months (p = 0.04) and for cumulative incidences of adverse events (p = 0.03) in favor of IM monotherapy (secondary endpoints).

CONCLUSION

IM/HU combination was more potent in selectively inhibiting CML cells in vitro, but not superior to IM in vivo. (NCT02480608).

Efficacy and safety of ABP 798 compared with rituximab: Results from the comparative clinical study in patients with non-Hodgkin’s

8044

Background: ABP 798* is being developed as a biosimilar to rituximab, a CD20-directed cytolytic antibody. A randomized, double-blind, active-controlled study compared the efficacy, safety, and immunogenicity of ABP 798 with rituximab reference product (RP) in subjects with CD20-positive NHL; results of the final analysis are presented here. Methods: Adult subjects with grade 1, 2, or 3a follicular B-cell NHL and low tumor burden were randomized to receive intravenous ABP 798 or RP (375 mg/m2) once weekly for 4 weeks, then at weeks 12 and 20. The primary endpoint was risk difference (RD) of overall response rate (ORR) by week 28. Secondary endpoints included RD of ORR at week 12, pharmacokinetics, pharmacodynamics, safety, and immunogenicity. Results: 254/256 randomized subjects were treated with at least one infusion of ABP 798 (n = 128) or RP (n = 126); ORR by week 28, based on independent central blinded assessment of the modified full analysis set, was comparable between the ABP 798 and RP groups (78% vs. 70%, respectively). The 2-sided 90% confidence interval of RD of ORR (-1.4%; 16.8%) was within the pre-specified margin (-15%; 35.5%) thereby establishing clinical equivalence between ABP 798 and RP. This result was supported by analyses of the secondary efficacy endpoint of RD of ORR at week 12. In the two groups, the geometric least squares means for serum concentrations over time (e.g., week 12, pre-dose: ABP 798, 21.89 vs. RP, 20.57; week 12 post-dose: ABP 798, 201.30 vs. RP, 203.52) and the extent of B-cell depletion from day 1 to day 8 (ABP 798, 98.3% vs. RP, 98.3%) were similar. Frequency, type, and severity of adverse events (AEs) were comparable between ABP 798 and RP groups; grade ≥3 AEs were reported in 10.9% and 10.3% of subjects and serious AEs in 3.9% and 4.0%, respectively. Most common AEs were headache, fatigue, and nausea; the most common AE of interest was infusion reactions. No new or unexpected safety signals were observed. Binding and neutralizing anti-drug antibodies were comparable between groups. Conclusions: Results of this study demonstrated clinical similarity between ABP 798 and rituximab RP in subjects with CD20-positive NHL. *At the time of this submission, ABP 798 had not been approved by the FDA or any relevant regulatory agency and the indications are yet undetermined. Please consult ABP 798’s later approved label in the relevant country for information regarding the approved uses for ABP 798.

Ruxolitinib for Glucocorticoid-Refractory Acute Graft-versus-Host Disease

BACKGROUND

Acute graft-versus-host disease (GVHD) remains a major limitation of allogeneic stem-cell transplantation; not all patients have a response to standard glucocorticoid treatment. In a phase 2 trial, ruxolitinib, a selective Janus kinase (JAK1 and JAK2) inhibitor, showed potential efficacy in patients with glucocorticoid-refractory acute GVHD.

METHODS

We conducted a multicenter, randomized, open-label, phase 3 trial comparing the efficacy and safety of oral ruxolitinib (10 mg twice daily) with the investigator's choice of therapy from a list of nine commonly used options (control) in patients 12 years of age or older who had glucocorticoid-refractory acute GVHD after allogeneic stem-cell transplantation. The primary end point was overall response (complete response or partial response) at day 28. The key secondary end point was durable overall response at day 56.

RESULTS

A total of 309 patients underwent randomization; 154 patients were assigned to the ruxolitinib group and 155 to the control group. Overall response at day 28 was higher in the ruxolitinib group than in the control group (62% [96 patients] vs. 39% [61]; odds ratio, 2.64; 95% confidence interval [CI], 1.65 to 4.22; P<0.001). Durable overall response at day 56 was higher in the ruxolitinib group than in the control group (40% [61 patients] vs. 22% [34]; odds ratio, 2.38; 95% CI, 1.43 to 3.94; P<0.001). The estimated cumulative incidence of loss of response at 6 months was 10% in the ruxolitinib group and 39% in the control group. The median failure-free survival was considerably longer with ruxolitinib than with control (5.0 months vs. 1.0 month; hazard ratio for relapse or progression of hematologic disease, non-relapse-related death, or addition of new systemic therapy for acute GVHD, 0.46; 95% CI, 0.35 to 0.60). The median overall survival was 11.1 months in the ruxolitinib group and 6.5 months in the control group (hazard ratio for death, 0.83; 95% CI, 0.60 to 1.15). The most common adverse events up to day 28 were thrombocytopenia (in 50 of 152 patients [33%] in the ruxolitinib group and 27 of 150 [18%] in the control group), anemia (in 46 [30%] and 42 [28%], respectively), and cytomegalovirus infection (in 39 [26%] and 31 [21%]).

CONCLUSIONS

Ruxolitinib therapy led to significant improvements in efficacy outcomes, with a higher incidence of thrombocytopenia, the most frequent toxic effect, than that observed with control therapy. (Funded by Novartis; REACH2 ClinicalTrials.gov number, NCT02913261.).