Jennifer Le-Rademacher

Impact of immune modulation with anti-T-cell antibodies on the outcome of reduced-intensity allogeneic hematopoietic stem cell transplantation for hematologic malignancies

The success of reduced intensity conditioning (RIC) transplantation is largely dependent on alloimmune effects. It is critical to determine whether immune modulation with anti-T-cell antibody infusion abrogates the therapeutic benefits of transplantation. We examined 1676 adults undergoing RIC transplantation for hematologic malignancies. All patients received alkylating agent plus fludarabine; 792 received allografts from a human leukocyte antigen-matched sibling, 884 from a 7 or 8 of 8 HLA-matched unrelated donor. Using Cox regression, outcomes after in vivo T-cell depletion (n = 584 antithymocyte globulin [ATG]; n = 213 alemtuzumab) were compared with T cell- replete (n = 879) transplantation. Grade 2 to 4 acute GVHD was lower with alemtuzumab compared with ATG or T cell- replete regimens (19% vs 38% vs 40%, P < .0001) and chronic GVHD, lower with alemtuzumab, and ATG regimens compared with T-replete approaches (24% vs 40% vs 52%, P < .0001). However, relapse was more frequent with alemtuzumab and ATG compared with T cell-replete regimens (49%, 51%, and 38%, respectively, P < .001). Disease-free survival was lower with alemtuzumab and ATG compared with T cell-replete regimens (30%, 25%, and 39%, respectively, P < .001). Corresponding probabilities of overall survival were 50%, 38%, and 46% (P = .008). These data suggest adopting a cautious approach to routine use of in vivo T-cell depletion with RIC regimens.

Double unit grafts successfully extend the application of umbilical cord blood transplantation in adults with acute leukemia.

UNLABELLED Cell dose is a major limitation for umbilical cord blood (UCB) transplantation because units containing a minimum of 2.5 x 10(7) total nucleated cells (TNC)/kilogram patient body weight are frequently not available. The transplantation of 2 partially HLA-matched UCB units has been adopted as a simple approach for increasing the TNC.We sought to determine whether the relative safety and efficacy of this approach was comparable with a single UCB transplantation. Included are adults with acute leukemia who received transplants with 1 (n =106) or 2 (n =303) UCB units. All UCB units for single UCB transplantations contained TNC ≥ 2.5 x 10(7)/kg. For double UCB transplantations, the total TNC for units 1 and 2 were > 2.5 x 10(7)/kg but in approximately half of these transplantations, 1 of the 2 units contained < 2.5 x 10(7) TNC/kg. Adjusting for factors associated with outcomes, risks of neutrophil recovery (odds ratio 0.83, P =.59), transplantation-related mortality (hazard ratio [HR] 0.91, P= .63), relapse (HR 0.90, P= .64), and overall mortality (HR 0.93, P= .62) was similar after double UCB and adequate dose single UCB transplantations. These data support double UCB unit transplantation for acute leukemia when an adequately dosed single UCB unit is not available thereby extending access to nearly all patients. KEY POINTS Efficacy of transplanting adequately dosed 1- or 2-cord blood units.

Hematopoietic Cell Transplantation for Systemic Mature T-Cell Non-Hodgkin Lymphoma

PURPOSE To analyze outcomes of hematopoietic cell transplantation (HCT) in T-cell non-Hodgkin lymphoma. PATIENTS AND METHODS Outcomes of 241 patients (112 anaplastic large-cell lymphoma, 102 peripheral T-cell lymphoma not otherwise specified, 27 angioimmunoblastic T-cell lymphoma) undergoing autologous HCT (autoHCT; n = 115; median age, 43 years) or allogeneic HCT (alloHCT; n = 126; median age, 38 years) were analyzed. Primary outcomes were nonrelapse mortality (NRM), relapse/progression, progression-free survival (PFS), and overall survival (OS). Patient, disease, and HCT-related variables were analyzed in multivariate Cox proportional hazard models to determine association with outcomes. RESULTS AutoHCT recipients were more likely in first complete remission (CR1; 35% v 14%; P = .001) and with chemotherapy-sensitive disease (86% v 60%; P < .001), anaplastic large-cell histology (53% v 40%; P = .04), and two or fewer lines of prior therapy (65% v 44%; P < .001) compared with alloHCT recipients. Three-year PFS and OS of autoHCT recipients beyond CR1 were 42% and 53%, respectively. Among alloHCT recipients who received transplantations beyond CR1, 31% remained progression-free at 3 years, despite being more heavily pretreated and with more refractory disease. NRM was 3.5-fold higher (95% CI, 1.80 to 6.99; P < .001) for alloHCT. In multivariate analysis, chemotherapy sensitivity (hazard ratio [HR], 1.8; 95% CI, 1.16 to 2.87) and two or fewer lines of pretransplantation therapy (HR, 5.02; 95% CI, 2.15 to 11.72) were prognostic of survival. CONCLUSION These data describe the roles of autoHCT and alloHCT in T-cell non-Hodgkin lymphoma and suggest greater effectiveness earlier in the disease course, and limited utility in multiply relapsed disease. Notably, autoHCT at relapse may be a potential option for select patients, particularly those with anaplastic large-cell lymphoma histology.

Myeloablative versus reduced-intensity hematopoietic cell transplantation for acute myeloid leukemia and myelodysplastic syndromes

Purpose The optimal regimen intensity before allogeneic hematopoietic cell transplantation (HCT) is unknown. We hypothesized that lower treatment-related mortality (TRM) with reduced-intensity conditioning (RIC) would result in improved overall survival (OS) compared with myeloablative conditioning (MAC). To test this hypothesis, we performed a phase III randomized trial comparing MAC with RIC in patients with acute myeloid leukemia or myelodysplastic syndromes. Patients and Methods Patients age 18 to 65 years with HCT comorbidity index ≤ 4 and < 5% marrow myeloblasts pre-HCT were randomly assigned to receive MAC (n = 135) or RIC (n = 137) followed by HCT from HLA-matched related or unrelated donors. The primary end point was OS 18 months post-random assignment based on an intent-to-treat analysis. Secondary end points included relapse-free survival (RFS) and TRM. Results Planned enrollment was 356 patients; accrual ceased at 272 because of high relapse incidence with RIC versus MAC (48.3%; 95% CI, 39.6% to 56.4% and 13.5%; 95% CI, 8.3% to 19.8%, respectively; P < .001). At 18 months, OS for patients in the RIC arm was 67.7% (95% CI, 59.1% to 74.9%) versus 77.5% (95% CI, 69.4% to 83.7%) for those in the MAC arm (difference, 9.8%; 95% CI, -0.8% to 20.3%; P = .07). TRM with RIC was 4.4% (95% CI, 1.8% to 8.9%) versus 15.8% (95% CI, 10.2% to 22.5%) with MAC ( P = .002). RFS with RIC was 47.3% (95% CI, 38.7% to 55.4%) versus 67.8% (95% CI, 59.1% to 75%) with MAC ( P < .01). Conclusion OS was higher with MAC, but this was not statistically significant. RIC resulted in lower TRM but higher relapse rates compared with MAC, with a statistically significant advantage in RFS with MAC. These data support the use of MAC as the standard of care for fit patients with acute myeloid leukemia or myelodysplastic syndromes.

Prospective cohort study comparing intravenous busulfan to total body irradiation in hematopoietic cell transplantation.

We conducted a prospective cohort study testing the noninferiority of survival of ablative intravenous busulfan (IV-BU) vs ablative total body irradiation (TBI)-based regimens in myeloid malignancies. A total of 1483 patients undergoing transplantation for myeloid malignancies (IV-BU, N = 1025; TBI, N = 458) were enrolled. Cohorts were similar with respect to age, gender, race, performance score, disease, and disease stage at transplantation. Most patients had acute myeloid leukemia (68% IV-BU, 78% TBI). Grafts were primarily peripheral blood (77%) from HLA-matched siblings (40%) or well-matched unrelated donors (48%). Two-year probabilities of survival (95% confidence interval [CI]), were 56% (95% CI, 53%-60%) and 48% (95% CI, 43%-54%, P = .019) for IV-BU (relative risk, 0.82; 95% CI, 0.68-0.98, P = .03) and TBI, respectively. Corresponding incidences of transplant-related mortality (TRM) were 18% (95% CI, 16%-21%) and 19% (95% CI, 15%-23%, P = .75) and disease progression were 34% (95% CI, 31%-37%) and 39% (95% CI, 34%-44%, P = .08). The incidence of hepatic veno-occlusive disease (VOD) was 5% for IV-BU and 1% with TBI (P < .001). There were no differences in progression-free survival and graft-versus-host disease. Compared with TBI, IV-BU resulted in superior survival with no increased risk for relapse or TRM. These results support the use of myeloablative IV-BU vs TBI-based conditioning regimens for treatment of myeloid malignancies.

Conditioning regimens for allotransplants for diffuse large B-cell lymphoma: myeloablative or reduced intensity?

The best conditioning regimen before allogeneic transplantation for high-risk diffuse large B-cell lymphoma (DLBCL) remains to be clarified. We analyzed data from 396 recipients of allotransplants for DLBCL receiving myeloablative (MAC; n = 165), reduced intensity (RIC; n = 143), or nonmyeloablative conditioning (NMAC; n = 88) regimens. Acute and chronic GVHD rates were similar across the groups. Five-year nonrelapse mortality (NRM) was higher in MAC than RIC and NMAC (56% vs 47% vs 36%; P = .007). Five-year relapse/progression was lower in MAC than in RIC/NMAC (26% vs 38% vs 40%; P = .031). Five-year progression-free survival (15%-25%) and overall survival (18%-26%) did not differ significantly between the cohorts. In multivariate analysis, NMAC and more recent transplant year were associated with lower NRM, whereas a lower Karnofsky performance score (< 90), prior relapse resistant to therapy, and use of unrelated donors were associated with higher NRM. NMAC transplants, no prior use of rituximab, and prior relapse resistant to therapy were associated with a greater risk of relapse/progression. In conclusion, allotransplantation with RIC or NMAC induces long-term progression-free survival in selected DLBCL patients with a lower risk of NRM but with higher risk of lymphoma progression or relapse.

Who is the better donor for older hematopoietic transplant recipients: an older-aged sibling or a young, matched unrelated volunteer?

Older patients are increasingly undergoing allogeneic hematopoietic transplantation. A relevant question is whether outcomes can be improved with a younger allele-level 8/8 HLA-matched unrelated donor (MUD) rather than an older HLA-matched sibling (MSD). Accordingly, transplants in leukemia/lymphoma patients age ≥50 years were analyzed comparing outcomes for recipients of MSD ≥50 (n = 1415) versus MUD <50 years (n = 757). Risks of acute graft-versus-host disease (GVHD) grade 2 to 4 (hazard ratio [HR], 1.63; P < .001), 3 to 4 (HR, 1.85; P < .001), and chronic GVHD (HR, 1.48; P < .0001) were higher after MUD compared with MSD transplants. The effect of donor type on nonrelapse mortality (NRM), relapse, and overall mortality was associated with performance score. For patients with scores of 90 or 100, NRM (HR, 1.42; P = .001), relapse (HR, 1.45; P < .001), and overall mortality (HR, 1.28; P = .001) risks were higher after MUD transplants. For patients with scores below 90, NRM (HR, 0.96; P = .76), relapse (HR, 0.86; P = .25), and overall mortality (HR, 0.90; P = .29) were not significantly different after MUD and MSD transplants. These data favor an MSD over a MUD in patients age ≥50 years.

Pembrolizumab in patients with CLL and Richter transformation or with relapsed CLL

Chronic lymphocytic leukemia (CLL) patients progressed early on ibrutinib often develop Richter transformation (RT) with a short survival of about 4 months. Preclinical studies suggest that programmed death 1 (PD-1) pathway is critical to inhibit immune surveillance in CLL. This phase 2 study was designed to test the efficacy and safety of pembrolizumab, a humanized PD-1-blocking antibody, at a dose of 200 mg every 3 weeks in relapsed and transformed CLL. Twenty-five patients including 16 relapsed CLL and 9 RT (all proven diffuse large cell lymphoma) patients were enrolled, and 60% received prior ibrutinib. Objective responses were observed in 4 out of 9 RT patients (44%) and in 0 out of 16 CLL patients (0%). All responses were observed in RT patients who had progression after prior therapy with ibrutinib. After a median follow-up time of 11 months, the median overall survival in the RT cohort was 10.7 months, but was not reached in RT patients who progressed after prior ibrutinib. Treatment-related grade 3 or above adverse events were reported in 15 (60%) patients and were manageable. Analyses of pretreatment tumor specimens from available patients revealed increased expression of PD-ligand 1 (PD-L1) and a trend of increased expression in PD-1 in the tumor microenvironment in patients who had confirmed responses. Overall, pembrolizumab exhibited selective efficacy in CLL patients with RT. The results of this study are the first to demonstrate the benefit of PD-1 blockade in CLL patients with RT, and could change the landscape of therapy for RT patients if further validated. This trial was registered at www.clinicaltrials.gov as #NCT02332980.

Allogeneic Hematopoietic Cell Transplantation for Fanconi Anemia in Patients With Pretransplantation Cytogenetic Abnormalities, Myelodysplastic Syndrome, or Acute Leukemia

PURPOSE Allogeneic hematopoietic cell transplantation (HCT) can cure bone marrow failure in patients with Fanconi anemia (FA). Data on outcomes in patients with pretransplantation cytogenetic abnormalities, myelodysplastic syndrome (MDS), or acute leukemia have not been separately analyzed. PATIENTS AND METHODS We analyzed data on 113 patients with FA with cytogenetic abnormalities (n = 54), MDS (n = 45), or acute leukemia (n = 14) who were reported to the Center for International Blood and Marrow Transplant Research from 1985 to 2007. RESULTS Neutrophil recovery occurred in 78% and 85% of patients at days 28 and 100, respectively. Day 100 cumulative incidences of acute graft-versus-host disease grades B to D and C to D were 26% (95% CI, 19% to 35%) and 12% (95% CI, 7% to 19%), respectively. Survival probabilities at 1, 3, and 5 years were 64% (95% CI, 55% to 73%), 58% (95% CI, 48% to 67%), and 55% (95% CI, 45% to 64%), respectively. In univariate analysis, younger age was associated with superior 5-year survival (≤ v > 14 years: 69% [95% CI, 57% to 80%] v 39% [95% CI, 26% to 53%], respectively; P = .001). In transplantations from HLA-matched related donors (n = 82), younger patients (≤ v > 14 years: 78% [95% CI, 64% to 90%] v 34% [95% CI, 20% to 50%], respectively; P < .001) and patients with cytogenetic abnormalities only versus MDS/acute leukemia (67% [95% CI, 52% to 81%] v 43% [95% CI, 27% to 59%], respectively; P = .03) had superior 5-year survival. CONCLUSION Our analysis indicates that long-term survival for patients with FA with cytogenetic abnormalities, MDS, or acute leukemia is achievable. Younger patients and recipients of HLA-matched related donor transplantations who have cytogenetic abnormalities only have the best survival.

Symbolic Covariance Principal Component Analysis and Visualization for Interval-Valued Data

This article proposes a new approach to principal component analysis (PCA) for interval-valued data. Unlike classical observations, which are represented by single points in p-dimensional space ℜp, interval-valued observations are represented by hyper-rectangles in ℜp, and as such, have an internal structure that does not exist in classical observations. As a consequence, statistical methods for classical data must be modified to account for the structure of the hyper-rectangles before they can be applied to interval-valued data. This article extends the classical PCA method to interval-valued data by using the so-called symbolic covariance to determine the principal component (PC) space to reflect the total variation of interval-valued data. The article also provides a new approach to constructing the observations in a PC space for better visualization. This new representation of the observations reflects their true structure in the PC space. Supplementary materials for this article are available online.