Bispecific T-cell engager therapy for gastrointestinal cancers

Though cancer immunotherapy has revolutionized the treatment of several tumor types, progress for immunotherapy in gastrointestinal (GI) tumors has been difficult. Recently, there have been rapid developments in bispecific T-cell engagers for the treatment of several hematologic malignancies. These can circumvent several limitations of conventional cancer immunotherapy by using bispecific antibodies to target CD3 and a tumor-specific antigen, thereby promoting anti-tumor cytotoxicity independent of major histocompatibility complex restriction or T-cell receptor specificity. Given the significant efficacy of this approach in leukemia, myeloma, and lymphoma, there is great interest in the potential for bispecific T-cell engagers in GI cancers. Here, we provide a comprehensive summary of current clinical and preclinical studies exploring bispecific T-cell engagers in GI cancers. Further, we briefly discuss potential barriers to therapeutic efficacy and important considerations regarding potential toxicity.