An international learning collaborative phase 2 trial for haploidentical bone marrow transplant in sickle cell disease.

ABSTRACT: In the setting of a learning collaborative, we conducted an international multicenter phase 2 clinical trial testing the hypothesis that nonmyeloablative-related haploidentical bone marrow transplant (BMT) with thiotepa and posttransplant cyclophosphamide (PTCy) will result in 2-year event-free survival (no graft failure or death) of at least 80%. A total of 70 participants were evaluable based on the conditioning protocol. Graft failure occurred in 8 of 70 (11.4%) and only in participants aged <18 years; all had autologous reconstitution. After a median follow-up of 2.4 years, the 2-year Kaplan-Meier-based probability of event-free survival was 82.6%. The 2-year overall survival was 94.1%, with no difference between children and adult participants. After excluding participants with graft failure (n = 8), participants with engraftment had median whole blood donor chimerism values at days +180 and +365 after transplant of 100% (n = 58), respectively, and 96.6% (57/59) were off immunosuppression 1 year after transplant. The 1-year grade 3 to 4 acute graft-versus-host disease (GVHD) rate was 10%, and the 2-year moderate-severe chronic GVHD rate was 10%. Five participants (7.1%) died from infectious complications. We demonstrate that nonmyeloablative haploidentical BMT with thiotepa and PTCy is a readily available curative therapy for most adults, even those with organ damage, compared to the more expensive myeloablative gene therapy and gene editing. Additional strategies are required for children to decrease graft failure rates. The trial was registered at www.clinicaltrials.gov as #NCT01850108.

Chimeric Antigen Receptor Structure and Manufacturing of Clinical Grade CAR Engineered Cells using Different Bioreactors.

Increasing success of adaptive cell therapy (ACT), such as genetically engineered T cells to express chimeric antigen receptors (CARs) proven to be highly significant technological advancements and impressive clinical outcomes in selected haematological malignancies, with promising efficacy. The evolution of CAR designs beyond the conventional structures is necessary to address some of the limitations of conventional CAR therapy and to expand the use of CAR T cells to a wider range of malignancies. There are various obstacles with a wide range of engineering strategies in order to improve the safety, efficacy and applicability of this therapeutic modality. Here we describe details of modular CAR structure with all the necessary domains and what is known about proximal CAR signalling in T cells. Furthermore, the global need for adoptive cell therapy is expanding very rapidly, and there is an urgent increasing demand for fully automated manufacturing methods that can produce large scale clinical grade high quality CAR engineered immune cells. Despite the advances in automation for the production of clinical grade CAR engineered cells, the manufacturing process is costly, consistent and involves multiple steps, including selection, activation, transduction, and Ex-Vivo expansion. Among these complex manufacturing phases, the choice of culture system to generate a high number of functional cells needs to be evaluated and optimized. Here we list the most advance fully automated to semi-automated bioreactor platforms can be used for the production of clinical grade CAR engineered cells for clinical trials but are far from being standardized. New processing options are available and a systematic effort seeking automation, standardization and the increase of production scale, would certainly help to bring the costs down and ultimately democratise this personalized therapy. In this review, we describe in detail different CAR engineered T cell platforms available and can be used in future for clinical-grade CAR engineered ATMP production.