Search

Chimeric antigen receptor (CAR) T cells are a rapidly emerging form of cancer treatment, and have resulted in remarkable responses in refractory lymphoid malignancies. However, their widespread clinical use is limited by toxicity related to cytokine release syndrome and neurotoxicity, the logistic complexity of their manufacturing, cost and time-to-treatment for autologous CAR-T cells, and the risk of graft-versus-host disease (GvHD) associated with allogeneic CAR-T cells. Natural killer (NK) cells have emerged as a promising source of cells for CAR-based therapies due to their ready availability and safety profile. NK cells are part of the innate immune system, providing the first line of defence against pathogens and cancer cells. They produce cytokines and mediate cytotoxicity without the need for prior sensitisation and have the ability to interact with, and activate other immune cells. NK cells for immunotherapy can be generated from multiple sources, such as expanded autologous or allogeneic peripheral blood, umbilical cord blood, haematopoietic stem cells, induced pluripotent stem cells, as well as cell lines. Genetic engineering of NK cells to express a CAR has shown impressive preclinical results and is currently being explored in multiple clinical trials. In the present review, we discuss both the preclinical and clinical trial progress made in the field of CAR NK-cell therapy, and the strategies to overcome the challenges encountered.

The past decade has witnessed tremendous progress in the treatment of acute lymphoblastic leukaemia (ALL), primarily due to the development of targeted therapies, including tyrosine kinase inhibitors targeting BCR-ABL1 tyrosine kinase, monoclonal antibodies targeting cell surface antigens (CD19, CD20 and CD22), bispecific antibodies and chimeric antigen receptor T- cell therapy. A number of new therapies have been approved by the US Food and Drug Administration in the past 5 years, including blinatumomab in 2014, inotuzumab ozagamicin in 2017 and tisagenlecleucel in 2017 for relapsed/refractory ALL. This has led to tremendous improvement in long-term survival, of more than 50% in patients with precursor B-ALL [50-70% in patients with Philadelphia chromosome (Ph)-positive ALL)], 50-60% in T-ALL and 80% in mature B-ALL. Research is ongoing to optimize the benefit of targeted therapeutics with the goal of decreasing the use of cytotoxic therapies.

Background Post-transplant lymphoproliferative disorders (PTLD) are a potentially fatal group of neoplasms arising in an immunodeficient environment. Although the cornerstone of treatment is reduced immunosuppression (RI), advanced cases often warrant treatment with chemoimmunotherapy. The chemoimmunotherapy regimen of dose-adjusted (DA)-EPOCH-R is superior to R-CHOP in HIV associated aggressive lymphomas, suggesting that it might also be favorable in the setting of PTLD. Methods We performed a retrospective analysis of patients with advanced monomorphic PTLD treated with first line DA-EPOCH-R in addition to RI at our institution from 2003-2016. Results Seven patients were included. Mean age was 51 and mean time from transplant to diagnosis was 71 months. Six of the seven patients received a kidney transplant, six had stage III or IV disease, six had tumors that were EBV positive, and six completed therapy. All six patients who completed therapy achieved a complete response. Mean PFS and OS were 46.6 and 52.6 months, respectively. Treatment was well-tolerated with no significant treatment related morbidity or mortality. Conclusions Our findings support several observations in the literature that DA-EPOCH-R is efficacious and well-tolerated for the treatment of advanced, monomorphic PTLD.