Advances in Peptide-Based Cancer Vaccines: Materials, Targeting, and Delivery Strategies

Immunotherapy, particularly immune checkpoint inhibitors (ICIs), has transformed cancer treatment by achieving durable responses in a subset of patients. However, the effectiveness of ICIs is often limited by factors such as low tumor expression of PD-L1 and low tumor mutational burden, which contribute to immune evasion in "cold" tumors. Cancer vaccination through the delivery of tumor antigens offers a promising strategy to enhance antigen-specific immune priming and improve the responses to ICIs. Despite this potential, peptide-based cancer vaccines face several challenges, including immune tolerance, insufficient antigen delivery and presentation, and the immunosuppressive tumor microenvironment. To overcome these barriers, novel platforms are being developed to codeliver antigens with immunostimulatory agents. In this review, we highlight recent advances in peptide-based cancer vaccine design, including innovative materials, adjuvants, targeting strategies, and controlled release mechanisms. We also discuss their translation and how these approaches may ultimately expand the benefit of immunotherapy to patients with treatment-refractory cancers. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Biology-Inspired Nanomaterials > Peptide-Based Structures Biology-Inspired Nanomaterials > Lipid-Based Structures.