Two-year follow-up of lisocabtagene maraleucel in relapsed or refractory large B-cell lymphoma in TRANSCEND NHL 001.

ABSTRACT: Lisocabtagene maraleucel (liso-cel) demonstrated significant efficacy with a manageable safety profile as third-line or later treatment for patients with relapsed or refractory (R/R) large B-cell lymphoma (LBCL) in the TRANSCEND NHL 001 study. Primary end points were adverse events (AEs), dose-limiting toxicities, and objective response rate (ORR) per independent review committee. Key secondary end points were complete response (CR) rate, duration of response (DOR), progression-free survival (PFS), and overall survival (OS). After 2-year follow-up, patients could enroll in a separate study assessing long-term (≤15 years) safety and OS. Liso-cel-treated patients (N = 270) had a median age of 63 years (range, 18-86 years) and a median of 3 prior lines (range, 1-8) of systemic therapy, and 181 of them (67%) had chemotherapy-refractory LBCL. Median follow-up was 19.9 months. In efficacy-evaluable patients (N = 257), the ORR was 73% and CR rate was 53%. The median (95% confidence interval) DOR, PFS, and OS were 23.1 (8.6 to not reached), 6.8 (3.3-12.7), and 27.3 months (16.2-45.6), respectively. Estimated 2-year DOR, PFS, and OS rates were 49.5%, 40.6%, and 50.5%, respectively. In the 90-day treatment-emergent period (N = 270), grade 3 to 4 cytokine release syndrome and neurological events occurred in 2% and 10% of patients, respectively. The most common grade ≥3 AEs in treatment-emergent and posttreatment-emergent periods, respectively, were neutropenia (60% and 7%) and anemia (37% and 6%). Liso-cel demonstrated durable remissions and a manageable safety profile with no new safety signals during the 2-year follow-up in patients with R/R LBCL. These trials were registered at www.ClinicalTrials.gov as #NCT02631044 and #NCT03435796.

Mosunetuzumab in combination with CHOP in previously untreated DLBCL: safety and efficacy results from a phase 2 study.

Up to 40% of patients with diffuse large B-cell lymphoma (DLBCL) are refractory to or relapse after first-line therapy, highlighting the need for better treatments. Mosunetuzumab is a CD20 × CD3 bispecific antibody that engages and redirects T cells to eliminate malignant B cells. In this phase 2, open-label study (NCT03677141), 40 patients (52.5% with international prognostic index ≥3) with previously untreated DLBCL initiated 6 cycles of IV mosunetuzumab with CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy. Mosunetuzumab was administered in cycle 1 as step-up doses to mitigate cytokine release syndrome [CRS], and a dose of 30 mg was given on day 1 of cycles 2-6. Efficacy end points included objective and complete response rates, as determined by the investigator, via positron emission tomography-computed tomography, using Lugano 2014 criteria (87.5% and 85.0%, respectively). At a median follow-up of 32.0 months, the estimated 2-year progression-free survival and event-free survival rates were 65.4% (95% confidence interval [CI], 49.5-81.4) and 60.4% (95% CI, 44.7-76.1), respectively. CRS occurred in 60.0% of patients; all events were grade 1 (45.0%) or grade 2 (15.0%) and occurred primarily in cycle 1. Mosunetuzumab-related grade ≥3 neurologic adverse events (AEs) potentially consistent with immune effector cell-associated neurotoxicity syndrome occurred in 1 patient (2.5%). Grade 5 AEs were reported in 2 patients. Neutropenia occurred in 70.0% of patients, mostly during cycle 1 and was of short duration. These findings demonstrate promising activity and a manageable safety profile for mosunetuzumab-CHOP and warrant further investigation of mosunetuzumab in first-line combination regimens for DLBCL.

Highly aminated iron oxide nanoworms for simultaneous manufacturing and labeling of chimeric antigen receptor T cells.

Cell based therapies including chimeric antigen receptor (CAR) T cells are promising for treating leukemias and solid cancers. At the same time, there is interest in enhancing the functionality of these cells via surface decoration with nanoparticles (backpacking). Magnetic nanoparticle cell labeling is of particular interest due to opportunities for magnetic separation, in vivo manipulation, drug delivery and magnetic resonance imaging (MRI). While modification of T cells with magnetic nanoparticles (MNPs) was explored before, we questioned whether MNPs are compatible with CAR-T cells when introduced during the manufacturing process. We chose highly aminated 120 nm crosslinked iron oxide nanoworms (CLIO NWs, ~36,000 amines per NW) that could efficiently label different adherent cell lines and we used CD123 CAR-T cells as the labeling model. The CD123 CAR-T cells were produced in the presence of CLIO NWs, CLIO NWs plus protamine sulfate (PS), or PS only. The transduction efficiency of lentiviral CD123 CAR with only NWs was ~23% lower than NW+PS and PS groups (~33% and 35%, respectively). The cell viability from these three transduction conditions was not reduced within CAR-T cell groups, though lower compared to non-transduced T cells (mock T). Use of CLIO NWs instead of, or together with cationic protamine sulfate for enhancement of lentiviral transduction resulted in comparable levels of CAR expression and viability but decreased the proportion of CD8+ cells and increased the proportion of CD4+ cells. CD123 CAR-T transduced in the presence of CLIO NWs, CLIO NWs plus PS, or PS only, showed similar level of cytotoxicity against leukemic cell lines. Furthermore, fluorescence microscopy imaging demonstrated that CD123 CAR-T cells labeled with CLIO NW formed rosettes with CD123+ leukemic cells as the non-labeled CAR-T cells, indicating that the CAR-T targeting to tumor cells has maintained after CLIO NW labeling. The in vivo trafficking of the NW labeled CAR-T cells showed the accumulation of CAR-T labeled with NWs primarily in the bone marrow and spleen. CAR-T cells can be magnetically labeled during their production while maintaining functionality using the positively charged iron oxide NWs, which enable the in vivo biodistribution and tracking of CAR-T cells.

Combined haploidentical and cord blood transplantation for refractory severe aplastic anaemia and hypoplastic myelodysplastic syndrome.

Umbilical cord blood (UCB) transplantation is a potentially curative treatment for patients with refractory severe aplastic anaemia (SAA), but has historically been associated with delayed engraftment and high graft failure and mortality rates. We conducted a prospective phase 2 trial to assess outcome of an allogeneic transplant regimen that co-infused a single UCB unit with CD34+ -selected cells from a haploidentical relative. Among 29 SAA patients [including 10 evolved to myelodysplastic syndrome (MDS)] who underwent the haplo cord transplantation (median age 20 years), 97% had neutrophil recovery (median 10 days), and 93% had platelet recovery (median 32 days). Early myeloid engraftment was from the haplo donor and was gradually replaced by durable engraftment from UCB in most patients. The cumulative incidences of grade II-IV acute and chronic graft-versus-host disease (GVHD) were 21% and 41%, respectively. With a median follow-up of 7·5 years, overall survival was 83% and GVHD/relapse-free survival was 69%. Patient- and transplant-related factors had no impact on engraftment and survival although transplants with haplo-versus-cord killer-cell immunoglobulin-like receptor (KIR) ligand incompatibility had delayed cord engraftment. Our study shows haplo cord transplantation is associated with excellent engraftment and long-term outcome, providing an alternative option for patients with refractory SAA and hypoplastic MDS who lack human leucocyte antigen (HLA)-matched donors.

Lisocabtagene maraleucel for patients with relapsed or refractory large B-cell lymphomas (TRANSCEND NHL 001): a multicentre seamless design study.

BACKGROUND: Lisocabtagene maraleucel (liso-cel) is an autologous, CD19-directed, chimeric antigen receptor (CAR) T-cell product. We aimed to assess the activity and safety of liso-cel in patients with relapsed or refractory large B-cell lymphomas. METHODS: We did a seamless design study at 14 cancer centres in the USA. We enrolled adult patients (aged ≥18 years) with relapsed or refractory large B-cell lymphomas. Eligible histological subgroups included diffuse large B-cell lymphoma, high-grade B-cell lymphoma with rearrangements of MYC and either BCL2, BCL6, or both (double-hit or triple-hit lymphoma), diffuse large B-cell lymphoma transformed from any indolent lymphoma, primary mediastinal B-cell lymphoma, and follicular lymphoma grade 3B. Patients were assigned to one of three target dose levels of liso-cel as they were sequentially tested in the trial (50 × 106 CAR+ T cells [one or two doses], 100 × 106 CAR+ T cells, and 150 × 106 CAR+ T cells), which were administered as a sequential infusion of two components (CD8+ and CD4+ CAR+ T cells) at equal target doses. Primary endpoints were adverse events, dose-limiting toxicities, and the objective response rate (assessed per Lugano criteria); endpoints were assessed by an independent review committee in the efficacy-evaluable set (comprising all patients who had confirmed PET-positive disease and received at least one dose of liso-cel). This trial is registered with ClinicalTrials.gov, NCT02631044. FINDINGS: Between Jan 11, 2016, and July 5, 2019, 344 patients underwent leukapheresis for manufacture of CAR+ T cells (liso-cel), of whom 269 patients received at least one dose of liso-cel. Patients had received a median of three (range 1-8) previous lines of systemic treatment, with 260 (97%) patients having had at least two lines. 112 (42%) patients were aged 65 years or older, 181 (67%) had chemotherapy-refractory disease, and seven (3%) had secondary CNS involvement. Median follow-up for overall survival for all 344 patients who had leukapheresis was 18·8 months (95% CI 15·0-19·3). Overall safety and activity of liso-cel did not differ by dose level. The recommended target dose was 100 × 106 CAR+ T cells (50 × 106 CD8+ and 50 × 106 CD4+ CAR+ T cells). Of 256 patients included in the efficacy-evaluable set, an objective response was achieved by 186 (73%, 95% CI 66·8-78·0) patients and a complete response by 136 (53%, 46·8-59·4). The most common grade 3 or worse adverse events were neutropenia in 161 (60%) patients, anaemia in 101 (37%), and thrombocytopenia in 72 (27%). Cytokine release syndrome and neurological events occurred in 113 (42%) and 80 (30%) patients, respectively; grade 3 or worse cytokine release syndrome and neurological events occurred in six (2%) and 27 (10%) patients, respectively. Nine (6%) patients had a dose-limiting toxicity, including one patient who died from diffuse alveolar damage following a dose of 50 × 106 CAR+ T cells. INTERPRETATION: Use of liso-cel resulted in a high objective response rate, with a low incidence of grade 3 or worse cytokine release syndrome and neurological events in patients with relapsed or refractory large B-cell lymphomas, including those with diverse histological subtypes and high-risk features. Liso-cel is under further evaluation at first relapse in large B-cell lymphomas and as a treatment for other relapsed or refractory B-cell malignancies. FUNDING: Juno Therapeutics, a Bristol-Myers Squibb Company.

Adult cord blood transplant results in comparable overall survival and improved GRFS vs matched related transplant.

We compared outcomes among adult matched related donor (MRD) patients undergoing peripheral blood stem cell transplantation and adult patients undergoing double unit cord blood transplantation (CBT) at our center between 2010 and 2017. A total of 190 CBT patients were compared with 123 MRD patients. Median follow-up was 896 days (range, 169-3350) among surviving CBT patients and 1262 days (range, 249-3327) among surviving MRD patients. Comparing all CBT with all MRD patients, overall survival (OS) was comparable (P = .61) and graft-versus-host disease (GVHD) relapse-free survival (GRFS) was significantly improved among CBT patients (P = .0056), primarily because of decreased moderate to severe chronic GVHD following CBT (P < .0001; hazard ratio [HR], 3.99; 95% confidence interval [CI], 2.26-7.04). Among patients undergoing our most commonly used MRD and umbilical cord blood (CB) myeloablative regimens, OS was comparable (P = .136) and GRFS was significantly improved among CBT patients (P = .006). Cumulative incidence of relapse trended toward decreased in the CBT group (P = .075; HR, 1.85; CI 0.94-3.67), whereas transplant-related mortality (TRM) was comparable (P = .55; HR, 0.75; CI, 0.29-1.95). Among patients undergoing our most commonly used nonmyeloablative regimens, OS and GRFS were comparable (P = .158 and P = .697). Cumulative incidence of both relapse and TRM were comparable (P = .32; HR, 1.35; CI, 0.75-2.5 for relapse and P = .14; HR, 0.482; CI, 0.18-1.23 for TRM). Our outcomes support the efficacy of CBT and suggest that among patients able to tolerate more intensive conditioning regimens at high risk for relapse, CB may be the preferred donor source.

Letermovir prophylaxis through day 100 post transplant is safe and effective compared with alternative CMV prophylaxis strategies following adult cord blood and haploidentical cord blood transplantation.

We compared CMV outcomes of three prophylactic approaches used for CBT and haploidentical cord transplants from December 2009 through 2018: letermovir (n = 32) through day 100 post transplant, "valacyclovir day 100" (valacyclovir 2 g orally three times daily through day 100) (n = 60), and "valacyclovir hospital discharge" (valacyclovir 2 g orally three times daily through hospital discharge then acyclovir 800 mg twice daily) (n = 41). Through day 100, none in the letermovir group, six (10%) in the "valacyclovir day 100," and nine (22%) in the "valacyclovir hospital discharge" group required CMV directed treatment (p = 0.005 and 0.06 comparing letermovir to "valacyclovir hospital discharge" and "valacyclovir day 100"). Fewer patients in the letermovir group (n = 7, 22%) had any CMV reactivation versus the "valacyclovir day 100" group (n = 20, 33%) versus the "valacyclovir hospital discharge" group (n = 23, 57%) (p = 0.003 and 0.21 comparing letermovir to "valacyclovir hospital discharge" and "valacyclovir day 100"). Among patients not reactivating CMV before 100 days, reactivation rates between day 100 and 180 were higher in the letermovir and "valacyclovir day 100" groups than the "valacyclovir hospital discharge" group. Letermovir is safe and effective compared with alternative prophylaxis approaches following CBT through day 100. Reactivation and monitoring after day 100 remain potential concerns.

Real-world experience of venetoclax with azacitidine for untreated patients with acute myeloid leukemia.

Venetoclax is approved for older untreated acute myeloid leukemia (AML) patients. Venetoclax was available prior to approval off-label. We assessed our single-institution off-label experience with venetoclax/azacitidine, comparing outcomes with a clinical trial cohort that administered this regimen at the same institution. Thirty-three untreated AML patients unfit or unwilling to receive induction chemotherapy and prescribed venetoclax/azacitidine off-trial were retrospectively analyzed and compared with 33 patients who received the same therapy on trial. Outcomes were compared, and comparisons were made to a theoretical scenario in which off-trial patients received induction. Digital droplet polymerase chain reaction evaluated measurable residual disease (MRD). Off-trial venetoclax was attainable in nearly all patients for whom this was desired. The complete remission (CR)/CR with incomplete blood count recovery rate was 63.3% for off-trial patients who received treatment and 84.9% for trial patients (P = .081). The median overall survival for off-trial patients who received treatment was 381 days (95% confidence interval [CI], 174, not reached) vs 880 days (95% CI, 384, not reached) for trial patients (P = .041). Prior exposure to hypomethylating agents was associated with worse outcomes. Response rates with venetoclax/azacitidine were not inferior to a theoretical scenario in which patients received induction, and early death rates were less than expected with induction. MRD negativity was achievable. Newly diagnosed AML patients treated in a "real-world" scenario with off-trial venetoclax/azacitidine had inferior outcomes compared with patients treated in the setting of a clinical trial. Additionally, this therapy may be as effective, and less toxic, when compared with induction chemotherapy.

CD123 CAR T cells for the treatment of myelodysplastic syndrome.

Myelodysplastic syndrome (MDS) is a group of heterogeneous disorders caused by ineffective hematopoiesis and characterized by bone marrow dysplasia and cytopenia. Current treatment options for MDS are limited to supportive care, hypomethylating agents, and stem cell transplant. Most patients eventually succumb to the disease or progress to leukemia. Previously, we found that CD123 can be used to delineate MDS stem cells in patients at high risk for MDS and that the CD123-positive population is biologically distinct from normal hematopoietic stem cells. Furthermore, selective targeting of MDS stem cells can dramatically reduce tumor burden in preclinical models. On the basis of these findings, we propose CD123 as a candidate target for chimeric antigen receptor (CAR) T-cell therapy in high-risk MDS patients. To test this concept, we employed a CAR lentiviral vector containing a CD123-specific single-chain variable fragment in combination with the CD28 costimulatory domain, CD3ζ signaling domain, and truncated estimated glomerular filtration rate. Utilizing this system, we illustrate that CD123 CAR can be expressed on both healthy donor and MDS patient-derived T lymphocytes with high efficiency, leading to the successful elimination of MDS stem cells both in vitro and in patient-derived xenografts. These results provide the concept for the use of CD123-targeted CAR T cells as a therapeutic option for patients with MDS.

Venetoclax with azacitidine disrupts energy metabolism and targets leukemia stem cells in patients with acute myeloid leukemia.

Acute myeloid leukemia (AML) is the most common acute leukemia in adults. Leukemia stem cells (LSCs) drive the initiation and perpetuation of AML, are quantifiably associated with worse clinical outcomes, and often persist after conventional chemotherapy resulting in relapse1-5. In this report, we show that treatment of older patients with AML with the B cell lymphoma 2 (BCL-2) inhibitor venetoclax in combination with azacitidine results in deep and durable remissions and is superior to conventional treatments. We hypothesized that these promising clinical results were due to targeting LSCs. Analysis of LSCs from patients undergoing treatment with venetoclax + azacitidine showed disruption of the tricarboxylic acid (TCA) cycle manifested by decreased α-ketoglutarate and increased succinate levels, suggesting inhibition of electron transport chain complex II. In vitro modeling confirmed inhibition of complex II via reduced glutathionylation of succinate dehydrogenase. These metabolic perturbations suppress oxidative phosphorylation (OXPHOS), which efficiently and selectively targets LSCs. Our findings show for the first time that a therapeutic intervention can eradicate LSCs in patients with AML by disrupting the metabolic machinery driving energy metabolism, resulting in promising clinical activity in a patient population with historically poor outcomes.

Characterization of clinical grade CD19 chimeric antigen receptor T cells produced using automated CliniMACS Prodigy system.

BACKGROUND: Chimeric antigen receptor (CAR) T-cell therapy is highly effective for treating acute lymphoblastic leukemia and non-Hodgkin's lymphoma with high rate complete responses. However, the broad clinical application of CAR T-cell therapy has been challenging, largely due to the lack of widespread ability to produce and high cost of CAR T-cell products using traditional methods of production. Automated cell processing in a closed system has emerged as a potential method to increase the feasibility of producing CAR T cells locally at academic centers due to its minimal reliance on experienced labor, thereby making the process less expensive and more consistent than traditional methods of production. METHOD: In this study, we describe the successful production of clinical grade CD19 CAR T cells using the Miltenyi CliniMACS Prodigy Automated Cell Processor at University of Colorado Anschutz Medical Campus in a rapid manner with a high frequent CD19 CAR expression. RESULTS: The final CAR T-cell product is highly active, low in immune suppression, and absent in exhaustion. Full panel cytokine assays also showed elevated production of Th1 cytokines upon IL-2 stimulation when specifically killing CD19+ target cells. CONCLUSION: These results demonstrate the feasibility of producing CAR T cells locally in a university hospital setting using automated cell processor for future clinical applications.

Subversion of Systemic Glucose Metabolism as a Mechanism to Support the Growth of Leukemia Cells.

From an organismal perspective, cancer cell populations can be considered analogous to parasites that compete with the host for essential systemic resources such as glucose. Here, we employed leukemia models and human leukemia samples to document a form of adaptive homeostasis, where malignant cells alter systemic physiology through impairment of both host insulin sensitivity and insulin secretion to provide tumors with increased glucose. Mechanistically, tumor cells induce high-level production of IGFBP1 from adipose tissue to mediate insulin sensitivity. Further, leukemia-induced gut dysbiosis, serotonin loss, and incretin inactivation combine to suppress insulin secretion. Importantly, attenuated disease progression and prolonged survival are achieved through disruption of the leukemia-induced adaptive homeostasis. Our studies provide a paradigm for systemic management of leukemic disease.

Chronic Myeloid Leukemia, Version 1.2019, NCCN Clinical Practice Guidelines in Oncology.

Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome (Ph), resulting from a reciprocal translocation between chromosomes 9 and 22 [t(9;22] that gives rise to a BCR-ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase. Tyrosine kinase inhibitor (TKI) therapy is a highly effective first-line treatment option for all patients with newly diagnosed chronic phase CML (CP-CML). The selection TKI therapy should be based on the risk score, toxicity profile of TKI, patient's age, ability to tolerate therapy, and the presence of comorbid conditions. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with CP-CML.

Thiotepa-Based Intensified Reduced-Intensity Conditioning Adult Double-Unit Cord Blood Hematopoietic Stem Cell Transplantation Results in Decreased Relapse Rate and Improved Survival Compared with Transplantation Following Standard Reduced-Intensity Conditioning: A Retrospective Cohort Comparison.

The "Minnesota" reduced-intensity conditioning (RIC) cord blood transplantation (CBT) regimen (standard RIC) of fludarabine (Flu) (200 mg/m2), cyclophosphamide (Cy) (50 mg/kg), and 200- or 300-cGy total body irradiation (TBI) is the most published RIC CBT regimen. Though well tolerated, high relapse rates remain a concern with this regimen. Intensification of conditioning may reduce relapse without increasing transplant-related mortality (TRM). We performed a retrospective cohort comparison of outcomes in adult patients who underwent first double-unit CBT with standard RIC as compared with the intensified regimen of Flu 150 mg/m2, Cy 50 mg/kg, thiotepa 10 mg/kg, and 400-cGy TBI (intensified RIC). Of the 99 patients studied, 47 received intensified RIC. Acute myelogenous leukemia was the major indication for transplant. The median age at transplant was 67 years (range, 24 to 74 years) and 54 years (range, 25 to 67 years) in standard RIC and intensified RIC, respectively. Median hematopoietic stem cell transplantation comorbidity index was 3 (range, 0 to 5) and 1 (range, 0 to 6) in the standard RIC and intensified RIC groups, respectively. Median follow-up among survivors was 22 months (range, 3.7 to 79 months) following standard RIC and 15 months (range, 2.8 to 36 months) following intensified RIC. The cumulative incidence (CI) of relapse was significantly lower following intensified RIC compared with standard RIC (P = .0013); this finding maintained significance in multivariate analysis (P = .045). TRM was comparable between the 2 groups (P = .99). Overall survival (OS) was significantly improved following intensified RIC as compared with standard RIC (P = .03). Median OS was 17 months following standard RIC versus not reached followed intensified RIC. The CI of grade II to IV acute graft-versus-host disease (GVHD) was significantly higher in the intensified RIC cohort than the standard RIC-cohort (P = .007), while CI of grade III to IV acute GVHD, any chronic GVHD, and moderate-to-severe chronic GVHD was comparable in each cohort (P = .20, P = .21, and P = .61, respectively). This retrospective analysis shows an improvement in OS and decreased relapse without increase in TRM in patients receiving intensified RIC as compared with standard RIC. Our data suggest that consideration of thiotepa-based intensified RIC may improve outcomes in fit, older patients undergoing double-unit CBT.

Allogeneic transplantation using CD34+ selected peripheral blood progenitor cells combined with non-mobilized donor T cells for refractory severe aplastic anaemia.

Allogeneic haematopoietic stem cell transplantation is curative for severe aplastic anaemia (SAA) unresponsive to immunosuppressive therapy. To reduce chronic graft-versus-host disease (GVHD), which occurs more frequently after peripheral blood stem cell (PBSC) transplantation compared to bone-marrow transplantation (BMT), and to prevent graft rejection, we developed a novel partial T-cell depleted transplant that infuses high numbers of granulocyte colony-stimulating factor-mobilized CD34+ selected PBSCs combined with a BMT-equivalent dose of non-mobilized donor T-cells. Fifteen patients with refractory SAA received cyclophosphamide, anti-thymocyte globulin and fludarabine conditioning, and were transplanted with a median 8 × 106 CD34+  cells/kg and 2 × 107 non-mobilized CD3+ T-cells/kg from human leucocyte antigen-matched sibling donors. All achieved sustained engraftment with only two developing acute and two developing chronic GVHD. With a 3·5-year median follow-up, 86% of patients survived and were transfusion-independent. When compared to a retrospective cohort of 56 bone-marrow failure patients that received the identical transplant preparative regimen and GVHD prophylaxis with the exception that the allograft contained unmanipulated PBSCs, partial T-cell depleted transplant recipients had delayed donor T-cell chimerism and relative reduction of 75% in the incidence of acute grade II-IV GVHD (13% vs. 52%; P = 0·010) and of 82% in chronic GVHD (13% vs. 72%; P = 0·0004). In multivariate analysis, partial T-cell depleted transplants remained significantly associated with a reduced risk of GVHD. In conclusion, for patients with refractory SAA, this novel transplant strategy achieves excellent engraftment and survival when compared to unmanipulated PBSC transplants and dramatically reduces the incidence of both acute and chronic GVHD.

Effect of high-dose plerixafor on CD34+ cell mobilization in healthy stem cell donors: results of a randomized crossover trial.

Hematopoietic stem cells can be mobilized from healthy donors using single-agent plerixafor without granulocyte colony-stimulating factor and, following allogeneic transplantation, can result in sustained donor-derived hematopoiesis. However, when a single dose of plerixafor is administered at a conventional 240 µg/kg dose, approximately one-third of donors will fail to mobilize the minimally acceptable dose of CD34+ cells needed for allogeneic transplantation. We conducted an open-label, randomized trial to assess the safety and activity of high-dose (480 µg/kg) plerixafor in CD34+ cell mobilization in healthy donors. Subjects were randomly assigned to receive either a high dose or a conventional dose (240 µg/kg) of plerixafor, given as a single subcutaneous injection, in a two-sequence, two-period, crossover design. Each treatment period was separated by a 2-week minimum washout period. The primary endpoint was the peak CD34+ count in the blood, with secondary endpoints of CD34+ cell area under the curve (AUC), CD34+ count at 24 hours, and time to peak CD34+ following the administration of plerixafor. We randomized 23 subjects to the two treatment sequences and 20 subjects received both doses of plerixafor. Peak CD34+ count in the blood was significantly increased (mean 32.2 versus 27.8 cells/µL, P=0.0009) and CD34+ cell AUC over 24 hours was significantly increased (mean 553 versus 446 h cells/µL, P<0.0001) following the administration of the 480 µg/kg dose of plerixafor compared with the 240 µg/kg dose. Remarkably, of seven subjects who mobilized poorly (peak CD34+ ≤20 cells/µL) after the 240 µg/kg dose of plerixafor, six achieved higher peak CD34+ cell numbers and all achieved higher CD34+ AUC over 24 hours after the 480 µg/kg dose. No grade 3 or worse drug-related adverse events were observed. This study establishes that high-dose plerixafor can be safely administered in healthy donors and mobilizes greater numbers of CD34+ cells than conventional-dose plerixafor, which may improve CD34+ graft yields and reduce the number of apheresis procedures needed to collect sufficient stem cells for allogeneic transplantation. (ClinicalTrials.gov, identifier: NCT00322127).

NCCN Guidelines Insights: Chronic Myeloid Leukemia, Version 1.2017.

The NCCN Guidelines for Chronic Myeloid Leukemia (CML) provide recommendations for the management of chronic-phase and advanced-phase CML in adult patients. The median age of disease onset is 67 years. However, because CML occurs in all age groups, clinical care teams should be prepared to address issues relating to fertility and pregnancy with patients who are of reproductive age at the time of diagnosis. CML is relatively rare in children and there are no evidence-based recommendations for the management of CML in pediatric population. These NCCN Guidelines Insights discuss special considerations for the management of CML during pregnancy and for the management of CML in the pediatric population.

Translocation (8;21) acute myeloid leukemia presenting as severe aplastic anemia.

We report a case of t(8;21) acute myeloid leukemia presenting as severe aplastic anemia. While initial bone marrow biopsy lacked any cytogenetic abnormalities in 20 analyzed metaphases, repeat bone marrow biopsy eight days later demonstrated this translocation. Initial cytogenetic analysis of 20 metaphases was therefore insufficient to make the diagnosis of hypocellular acute myeloid leukemia. We discuss that further complementary molecular tests, such as CGH, would likely provide a more robust diagnosis of hematopoietic diseases.