Improved Efficacy of Antibody Cancer Immunotherapeutics through Local and Sustained Delivery

Antibodies are a growing class of cancer immunotherapeutics that facilitate immune‐cell‐mediated killing of tumors. However, the efficacy and safety of immunotherapeutics are limited by transport barriers and poor tumor uptake, which lead to high systemic concentrations and potentially fatal side effects. To increase tumor antibody immunotherapeutic concentrations while decreasing systemic concentrations, local delivery vehicles for sustained antibody release are being developed. The focus of this review is to define the material properties required for implantable controlled antibody delivery and highlight the controlled‐release strategies that are applicable to antibody immunotherapeutics. Less is more: sustained local delivery of antibody immunotherapeutics (AImTs) from implanted hydrogels improves the efficacy of cancer immunotherapies by increasing tumor AImT concentrations and lowering the incidence rate of side effects by decreasing systemic concentrations.