Chimeric antigen receptor (CAR-) T cell therapy is a revolutionary immunotherapy platform which has demonstrated remarkable responses in B cell leukemia and lymphoma. In contrast, the efficacy of CAR-T cells against solid tumors to date has been limited. Solid cancers are highly heterogeneous and their endogenous immunosuppressive microenvironment coupled with mutation-induced antigen escape may result in disease recurrence following CAR-T treatment. To mitigate tumour escape through loss of the nominal target antigen, we have developed dual CAR-T cells targeting both TAG-72 and CD47. Initial investigations focused on the production of second-generation, mono-specific CAR-T cells targeting either TAG-72 or CD47 where the scFv was linked via hinge and transmembrane (TM) domains to an intracellular signaling domain. Given CD47 is ubiquitously expressed on many cell types, including T cells, it was not surprising to find that full signaling CD47 CAR-T cells demonstrated reduced viability through fratricide and an associated reduction in proliferative capacity compared to TAG-72 mono-specific CAR-T cells. To overcome this, non-signaling CD47 (DCD47) CAR-T cells were produced. This approach improved ex vivo expansion and viability. We then generated bicistronic, second-generation dual CAR constructs where intracellular signaling domains (either CD28 or 4-1BB) were linked to the TAG-72 scFv via hinge and TM regions however, importantly, the CD47 scFv was devoid of any signaling domain (TAG-72/DCD47). The relative cytotoxic effect of these variant CAR-T cells was evaluated using the real time impedance-based assay, xCELLigence. Dual CAR-T cells were potent killers of both TAG-72hi/CD47hi and TAG-72low/CD47hi target cells in vitro. These data were supported by increased levels of IFNg and IL-2 production as determined by cytokine array. Surprisingly, these dual CAR-T cells were able to kill non-cancerous target cell lines derived from healthy tissues (TAG-72low/CD47low). We postulated that this was due to binding avidity dictated by the CAR arrangement at the cell surface where scFv dimerization can occur via the interaction of cysteine residues within the hinge and TM domains, effectively allowing the DCD47 CAR to signal. To overcome this, point mutations (Cys-Ser) were introduced into the hinge and TM domains resulting in monomerization of the DCD47 CAR receptor (DCD47m). Importantly, cytotoxic activity against TAG-72low/CD47low healthy cell lines was now ameliorated and monomerization of DCD47 CAR did not impact the ability for TAG-72/DCD47m dual CAR-T cells to eliminate TAG-72hi/CD47hi cancerous target cells in vitro and in vivo. The TAG-72/DCD47m truncated CAR-T cells are being further evaluated as a novel dual CAR strategy for ovarian cancer.