Citations

Abstract Purpose: To develop a prognostic model and cytogenetic risk classification for previously treated patients with chronic lymphocytic leukemia (CLL) undergoing reduced intensity conditioning (RIC) allogeneic hematopoietic cell transplantation (HCT). Experimental Design: We performed a retrospective analysis of outcomes of 606 patients with CLL who underwent RIC allogeneic HCT between 2008 and 2014 reported to the Center for International Blood and Marrow Transplant Research. Results: On the basis of multivariable models, disease status, comorbidity index, lymphocyte count, and white blood cell count at HCT were selected for the development of prognostic model. Using the prognostic score, we stratified patients into low-, intermediate-, high-, and very-high-risk [4-year progression-free survival (PFS) 58%, 42%, 33%, and 25%, respectively, P < 0.0001; 4-year overall survival (OS) 70%, 57%, 54%, and 38%, respectively, P < 0.0001]. We also evaluated karyotypic abnormalities together with del(17p) and found that del(17p) or ≥5 abnormalities showed inferior PFS. Using a multivariable model, we classified cytogenetic risk into low, intermediate, and high (P < 0.0001). When the prognostic score and cytogenetic risk were combined, patients with low prognostic score and low cytogenetic risk had prolonged PFS (61% at 4 years) and OS (75% at 4 years). Conclusions: In this large cohort of patients with previously treated CLL who underwent RIC HCT, we developed a robust prognostic scoring system of HCT outcomes and a novel cytogenetic-based risk stratification system. These prognostic models can be used for counseling patients, comparing data across studies, and providing a benchmark for future interventions. For future study, we will further validate these models for patients receiving targeted therapies prior to HCT.

Background:PRM‐151, a recombinant human pentraxin‐2 molecule, prevents and reverses fibrosis in animal models of myelofibrosis (MF) in part by targeting differentiation of fibrocytes from monocytes. In the first stage of a two‐stage trial, treatment of patients (pts) with primary (PMF), post‐essential thrombocythemia/polycythemia vera (post‐ET/PV) MF with PRM‐151 ± ruxolitinib (Rux) was associated with decreases in bone marrow fibrosis (BMF), improvements in hemoglobin (Hgb) and platelets (PLT), reductions in transfusions and symptoms, and modest reductions in splenomegaly.Aims:Here, we report efficacy and safety data from a stage 2 randomized, double‐blind evaluation of single agent PRM‐151.Methods:Pts with DIPPS Int‐1, Int‐2, and high risk PMF or post‐ET/PV MF who were ineligible for, intolerant of, or had an inadequate response to Rux were randomized between 0.3, 3, and 10 mg/kg of PRM‐151 as a sole agent. PRM‐151 was to be administered by IV infusion at one of the three assigned doses on Days 1, 3, and 5 of Cycle 1 and on Day 1 of each subsequent 28‐day cycle for at least 9 cycles. Randomization was stratified according to baseline (BL) Hgb <100 g/L receiving transfusions and/or PLT <50 x 109/L. Bone marrow biopsies and imaging for spleen volume were obtained at BL, C4D1, C7D1, and C9D29. BMF score was evaluated centrally by three independent, blinded hematopathologists. The primary objective of the study was to determine the effect size of three different doses of PRM‐151 on reduction in BMF by ≥ 1 grade at any time during the study.Results:Of the 98 randomized patients, 97 were treated with 0.3 mg/kg (n = 33), 3 mg/kg (n = 32), or 10 mg/kg (n = 32). BL characteristics are provided in Table 1. Forty‐six pts discontinued treatment prior to Cycle 9. Decrease in BMF grade at any time was observed in 10 of 33 pts (30%) at 0.3 mg/kg, 9 of 31 pts (28%) at 3 mg/kg, and 8 of 32 pts (25%) at 10 mg/kg. Decrease in BM collagen grade was observed in 31–37% of pts. In pts who were RBC transfusion dependent or with Hgb <100 g/L and transfusion independent at BL, 16–29% of pts had ≥50% reduction in RBC transfusions or Hgb increases ≥10 g/L for ≥12 consecutive weeks. In pts who were PLT transfusion dependent or with PLT<25 or PLT25‐<50 x 109/L and transfusion independent at BL, 31–40% of pts had ≥50% reduction in PLT transfusions, PLT ≥25 x 109/L or PLT ≥50 x 109/L or doubling of PLT count, without transfusions for ≥12 consecutive weeks. Improvement from BL in MPN‐SAF TSS of ≥25% for ≥12 consecutive weeks was observed in 10–26% of pts. Reduction in spleen volume was observed with a maximum reduction of 34% in one pt. Response rates for BM collagen, Hgb, PLT, MPN‐SAF, and spleen were generally similar across the three dose levels. The most common treatment emergent adverse events (AEs) were fatigue, cough, thrombocytopenia, and abnormal weight loss. A majority of the AEs were Grade 2 or lower in severity and consistent with disease progression. Grade 3 and 4 related AEs were reported in 12% and 6% of pts, respectively.Summary/Conclusion:The study enrolled a large proportion of MF pts with advanced disease (Int‐2 or high risk, BMF grade 3, anemic/transfusion dependent, and PLT <50 x 109/L). Decrease in BMF and collagen grade were observed across all dose levels. Increases in Hgb and PLT count or reduction in transfusion requirements were also reported across all dose levels. Improvements in MPN‐SAF TSS and spleen volume were observed in a proportion of pts. PRM‐151 treatment for up to 9 cycles was well tolerated. These data warrant confirmation in a larger controlled study.image

Abstract HLA-haploidentical hematopoietic cell transplantation (Haplo-HCT) using posttransplantation cyclophosphamide (PT-Cy) has improved donor availability. However, a matched sibling donor (MSD) is still considered the optimal donor. Using the Center for International Blood and Marrow Transplant Research database, we compared outcomes after Haplo-HCT vs MSD in patients with acute myeloid leukemia (AML) in first complete remission (CR1). Data from 1205 adult CR1 AML patients (2008-2015) were analyzed. A total of 336 patients underwent PT-Cy–based Haplo-HCT and 869 underwent MSD using calcineurin inhibitor–based graft-versus-host disease (GVHD) prophylaxis. The Haplo-HCT group included more reduced-intensity conditioning (65% vs 30%) and bone marrow grafts (62% vs 7%), consistent with current practice. In multivariable analysis, Haplo-HCT and MSD groups were not different with regard to overall survival (P = .15), leukemia-free survival (P = .50), nonrelapse mortality (P = .16), relapse (P = .90), or grade II-IV acute GVHD (P = .98). However, the Haplo-HCT group had a significantly lower rate of chronic GVHD (hazard ratio, 0.38; 95% confidence interval, 0.30-0.48; P &lt; .001). Results of subgroup analyses by conditioning intensity and graft source suggested that the reduced incidence of chronic GVHD in Haplo-HCT is not limited to a specific graft source or conditioning intensity. Center effect and minimal residual disease–donor type interaction were not predictors of outcome. Our results indicate a lower rate of chronic GVHD after PT-Cy–based Haplo-HCT vs MSD using calcineurin inhibitor–based GVHD prophylaxis, but similar other outcomes, in patients with AML in CR1. Haplo-HCT is a viable alternative to MSD in these patients.

Abstract A limited number of drugs are available to treat patients with polycythemia vera (PV) and essential thrombocythemia (ET). We attempted to identify alternative agents that may target abnormalities within malignant hematopoietic stem (HSCs) and progenitor cells (HPCs). Previously, MDM2 protein levels were shown to be upregulated in PV/ET CD34+ cells, and exposure to a nutlin, an MDM2 antagonist, induced activation of the TP53 pathway and selective depletion of PV HPCs/HSCs. This anticlonal activity was mediated by upregulation of p53 and potentiated by the addition of interferon-α2a (IFN-α2a). Therefore, we performed an investigator-initiated phase 1 trial of the oral MDM2 antagonist idasanutlin (RG7388; Roche) in patients with high-risk PV/ET for whom at least 1 prior therapy had failed. Patients not attaining at least a partial response by European LeukemiaNet criteria after 6 cycles were then allowed to receive combination therapy with low-dose pegylated IFN-α2a. Thirteen patients with JAK2 V617F+ PV/ET were enrolled, and 12 (PV, n = 11; ET, n = 1) were treated with idasanutlin at 100 and 150 mg daily, respectively, for 5 consecutive days of a 28-day cycle. Idasanutlin was well tolerated; no dose-limiting toxicity was observed, but low-grade gastrointestinal toxicity was common. Overall response rate after 6 cycles was 58% (7 of 12) with idasanutlin monotherapy and 50% (2 of 4) with combination therapy. Median duration of response was 16.8 months (range, 3.5-26.7). Hematologic, symptomatic, pathologic, and molecular responses were observed. These data indicate that idasanutlin is a promising novel agent for PV; it is currently being evaluated in a global phase 2 trial. This trial was registered at www.clinicaltrials.gov as #NCT02407080.