Implantable Biomaterials for Cancer Immunotherapies

Abstract Cancer immunotherapy has revolutionized cancer treatment by leveraging the immune system to target and eliminate tumor cells. Implantable biomaterials, such as hydrogels, sponges, scaffolds, implantable microdevice platforms, and macrobeads, offer localized and sustained release of immunomodulatory agents, improving the delivery of treatments such as immune checkpoint inhibitors, cancer vaccines, and adoptive cell therapies like CAR‐T cells. This review examines the emerging role of these biomaterials in modulating the tumor microenvironment, enhancing immune cell recruitment, and reducing systemic side effects, positioning them as significant tools for treating solid tumors. Recent advances in material engineering are also discussed, including the integration of bioactive molecules and real‐time therapeutic adjustments based on patient‐specific immune responses, which offer new potential in personalized cancer treatments. However, challenges such as biocompatibility, high production costs, variability in patient response, and the necessity of surgical manipulations remain key obstacles. Nonetheless, ongoing research and technological advancements are steadily addressing these issues, paving the way for more effective and accessible cancer immunotherapies. Overall, this review highlights the promise of implantable biomaterials overcoming the current limitations of cancer immunotherapy and expanding the scope of effective, targeted cancer treatments.