Anti-CD19 chimeric antigen receptor (CAR) T-cell therapy has shown remarkable clinical efficacy in B-cell cancers. However, CAR T cells can induce substantial toxic effects, and the manufacture of ...the cells is complex. Natural killer (NK) cells that have been modified to express an anti-CD19 CAR have the potential to overcome these limitations.
In this phase 1 and 2 trial, we administered HLA-mismatched anti-CD19 CAR-NK cells derived from cord blood to 11 patients with relapsed or refractory CD19-positive cancers (non-Hodgkin's lymphoma or chronic lymphocytic leukemia CLL). NK cells were transduced with a retroviral vector expressing genes that encode anti-CD19 CAR, interleukin-15, and inducible caspase 9 as a safety switch. The cells were expanded ex vivo and administered in a single infusion at one of three doses (1×10
, 1×10
, or 1×10
CAR-NK cells per kilogram of body weight) after lymphodepleting chemotherapy.
The administration of CAR-NK cells was not associated with the development of cytokine release syndrome, neurotoxicity, or graft-versus-host disease, and there was no increase in the levels of inflammatory cytokines, including interleukin-6, over baseline. The maximum tolerated dose was not reached. Of the 11 patients who were treated, 8 (73%) had a response; of these patients, 7 (4 with lymphoma and 3 with CLL) had a complete remission, and 1 had remission of the Richter's transformation component but had persistent CLL. Responses were rapid and seen within 30 days after infusion at all dose levels. The infused CAR-NK cells expanded and persisted at low levels for at least 12 months.
Among 11 patients with relapsed or refractory CD19-positive cancers, a majority had a response to treatment with CAR-NK cells without the development of major toxic effects. (Funded by the M.D. Anderson Cancer Center CLL and Lymphoma Moonshot and the National Institutes of Health; ClinicalTrials.gov number, NCT03056339.).
The incorporation of tyrosine kinase inhibitors (TKI) into front-line therapy for adults with Philadelphia chromosome positive acute lymphoblastic leukemia has dramatically altered response rates and ...significantly improved outcomes, such that this entity may no longer be considered a high risk acute lymphoblastic leukemia subgroup. In this review article, we summarize approaches to front-line therapy in the TKI era, including intensive chemotherapy-based regimens and deintensified therapy. We also review optimal disease monitoring strategies, discuss the role of consolidative hematopoietic cell transplantation, and touch on options for relapsed disease. The incorporation of novel targeted agents in conjunction with TKIs into front-line therapy will likely alter the future therapeutic approaches to this disease.
Chimeric antigen receptor (CAR) T-cell therapy targeting CD19 may be associated with long-term adverse effects such as cytopenia and immune deficiency. In order to characterize these late events, we ...analyzed 31 patients with relapsed or refractory large B-cell lymphoma treated with axicabtagene ciloleucel at our institution on two clinical trials, ZUMA-1 (clinicaltrials gov. Identifier: NCT02348216) and ZUMA-9 (clinicaltrials gov. Identifier: NCT03153462). Complete blood counts, lymphocyte subsets, and immunoglobulin levels were measured serially until month 24 or progression. Fifteen (48%) patients had grade 3-4 cytopenia, including anemia (five, 16%), neutropenia (nine, 29%), or thrombocytopenia (13, 42%) at day 30. Cytopenia at day 30 was not significantly associated with later diagnosis of myelodysplasia. Among patients with ongoing remission, grade 3-4 cytopenia was observed in one of nine (11%) at 2 years. While peripheral CD8+ T cells recovered early, CD4+ T-cell recovery was delayed with a count of <200/mL in three of nine (33%) patients at 1 year and two of seven (29%) at 2 years. Immunoglobulin G levels normalized in five of nine (56%) patients at 2 years. Thirteen (42%) patients developed grade 3-4 infectious complications, including herpes zoster and Pneumocystis jiroveci pneumonia. These results suggest the need for prolonged monitoring and prophylaxis against opportunistic infections in these patients, to improve the longterm safety of axicabtagene ciloleucel therapy.
Graft-versus-host disease (GVHD) is the major limitation of allogeneic haemopoietic stem-cell transplantation (HSCT), for which no approved treatments are available. Use of mesenchymal stromal cells ...(MSCs) has become standard practice in some European countries, but controversy exists for their benefit. The aim of this meta-analysis was to analyse available evidence for the benefit of MSC treatments in steroid-resistant acute GVHD.
We did a systematic review and meta-analysis to assess response to and survival after MSC treatment in patients with steroid-refractory acute GVHD. We searched MEDLINE, Embase, Ovid, and Cochrane Central databases for published studies, and we used ClinicalTrials.gov and other websites to find unpublished studies and conference abstracts. We included prospective and retrospective studies in which MSCs were administered to patients with steroid-refractory acute GVHD. Data were extracted independently by two investigators based on strict selection criteria. A random-effects model was used to pool outcomes across studies because of anticipated heterogeneity. Our primary outcome was survival at 6 months from the first infusion of MSCs.
We identified 628 citations with our search, of which 610 were excluded after review and a further five did not contain pertinent data. Thus, our meta-analysis included 13 non-randomised studies at moderate risk of bias, comprising a total of 336 patients. Six studies provided data for the primary outcome analysis (119 patients). Survival at 6 months after MSC treatment was 63% (95% CI 50-74; I(2)=41%). Survival did not differ with respect to age, MSC culture medium, or dose of MSCs delivered.
Available evidence suggests that infusion of MSCs could be an acceptable treatment for patients with steroid-refractory acute GVHD. Randomised clinical trials are needed urgently to assess different treatment modalities for steroid-refractory acute GVHD.
None.
Purpose of Review
Over the past two decades, tyrosine kinase inhibitors (TKIs) have changed the management of patients with Philadelphia chromosome–positive (Ph+) acute lymphoblastic leukemia (ALL), ...and this has led to significant improvement in their outcome. In this review, we will provide an overview of the current understanding of treatment of Ph+ ALL focusing on TKIs, alloHSCT, and novel therapies.
Recent findings
The advent of more potent TKIs and the novel therapeutic options including blinatumomab, inotuzumab ozogamicin, and CD19 CAR-T therapy has changed the role of allogeneic hematopoietic stem cell transplant (alloHSCT) and intensive chemotherapy. To avoid toxicity from the historical treatment strategies, a more individualized, targeted approach to therapy including detection and monitoring of measurable residual disease (MRD) has become of interest.
Summary
The treatment of patients with Ph+ ALL has been rapidly evolving with a more individualized, targeted treatment and use of TKIs and novel therapy.
Summary Background The outlook for patients with refractory and relapsed acute lymphocytic leukaemia (ALL) is poor. CD22 is highly expressed in patients with ALL. Inotuzumab ozogamicin is a CD22 ...monoclonal antibody conjugated to the toxin calecheamicin. We did a phase 2 study to assess the efficacy of this antibody. Methods We recruited patients at the MD Anderson Cancer Center, Houston, TX, USA, between June, 2010, and March, 2011. Adults and children with refractory and relapsed ALL were eligible. Ten adults were treated before enrolment of children started. Patients were given 1·8 mg/m2 inotuzumab ozogamicin intravenously over 1 h every 3–4 weeks (the first three adults and three children received 1·3 mg/m2 in the first course). The primary endpoint was overall response (complete response or marrow complete response with no recovery of platelet count or incomplete recovery of neutrophil and platelet counts). Analysis was done by intention to treat. This study is registered, number NCT01134575. Findings 49 patients were enrolled and treated. Median age was 36 years (range 6–80). CD22 was expressed in more than 50% of blasts in all patients. The median number of courses was two (range one to five) and the median time between courses was 3 weeks (range 3–6). Nine (18%) patients had complete response, 19 (39%) had marrow complete response, 19 (39%) had resistant disease, and two (4%) died within 4 weeks of starting treatment. The overall response rate was 57% (95% CI 42–71). The most frequent adverse events during course one of treatment were fever (grade 1–2 in 20 patients, grade 3–4 in nine), hypotension (grade 1–2 in 12 patients, grade 3 in one), and liver-related toxic effects (bilirubin: grade 1–2 in 12 patients, grade 3 in two; raised aminotransferase concentration: grade 1–2 in 27 patients, grade 3 in one). Interpretation Inotuzumab ozogamicin shows promise as a treatment for refractory and relapsed ALL. Funding Pfizer.
Steroids remain the initial therapy for acute graft-vs.-host disease (AGVHD). Strategies to improve response and minimize steroid exposure are needed. We report results of a randomized, adaptive, ...Bayesian-designed, phase II trial of prednisone with or without extracorporeal photopheresis (ECP) as an initial therapy for patients with newly diagnosed AGVHD. The primary endpoint was success at day 56 defined as: alive, in remission, achieving AGVHD response without additional therapy, and on <1 mg/kg at day 28 and <0.5 mg/kg on day 56 of steroids. Eighty-one patients were randomized to the ECP arm (n = 51) or steroids alone (n = 30). Median age was 54 years (range: 17-75); 90% had grade II AGVHD and 10% had grades III and IV AGVHD, with skin (85%), upper (22%)/lower (22%) gastrointestinal, and liver (10%) involvement. The ECP arm had a higher probability of success (0.815) and exceeded the predefined threshold for determining the investigational arm promising. ECP was potentially more beneficial than steroids-alone in skin-only AGVHD (response rate: 72% vs. 57%, respectively) than for visceral-organ AGVHD (47% vs. 43%, respectively). The addition of ECP to steroids may result in higher GVHD response as initial therapy for AGVHD, especially for patients with skin-only involvement.
Long-term engraftment of allogeneic cells necessitates eluding immune-mediated rejection, which is currently achieved by matching for human leukocyte antigen (HLA) expression, immunosuppression, ...and/or delivery of donor-derived cells to sanctuary sites. Genetic engineering provides an alternative approach to avoid clearance of cells that are recognized as “non-self” by the recipient. To this end, we developed designer zinc finger nucleases and employed a “hit-and-run” approach to genetic editing for selective elimination of HLA expression. Electro-transfer of mRNA species coding for these engineered nucleases completely disrupted expression of HLA-A on human T cells, including CD19-specific T cells. The HLA-Aneg T-cell pools can be enriched and evade lysis by HLA-restricted cytotoxic T-cell clones. Recognition by natural killer cells of cells that had lost HLA expression was circumvented by enforced expression of nonclassical HLA molecules. Furthermore, we demonstrate that zinc finger nucleases can eliminate HLA-A expression from embryonic stem cells, which broadens the applicability of this strategy beyond infusing HLA-disparate immune cells. These findings establish that clinically appealing cell types derived from donors with disparate HLA expression can be genetically edited to evade an immune response and provide a foundation whereby cells from a single donor can be administered to multiple recipients.
•Allogeneic-donor–derived cells can be genetically modified to eliminate expression of HLA-A.•HLA-A disruption from donor cells is a step toward generating allogeneic cells as an off-the-shelf therapeutic.
Use of adoptive T-cell therapy modified with chimeric antigen receptor (CAR-T) has revolutionized treatment of patients with relapsed/refractory (r/r) B-cell acute lymphoblastic leukemia (B-ALL). ...CAR-T cells directed against CD19 antigen have produced response rates as high as 90% in clinical trials for r/r B-ALL. Despite high rates of complete remissions, the durability of responses has been sub-optimal with frequent relapses, especially in adult B-ALL population. Systemic toxicities from CAR-T therapy and standardization of toxicities grading and management is another major hurdle in the development of CAR-T field. In this review, we discuss the latest evidence of CAR-T therapy in B-ALL, potential mechanisms of relapse and barriers to CAR-T cell therapy in B-ALL. We also debate the role of allogeneic hematopoietic stem cell transplant (allo-HCT) post CAR-T therapy.
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