Drug Delivery System for Cancer Immunotherapy: Potential Roles, Challenge and Recent Advances

Immunotherapy has emerged as a pivotal advancement in oncological therapeutics, representing a paradigm shift from conventional treatment modalities including surgery, radiotherapy, and chemotherapy. This innovative approach demonstrates considerable clinical potential through its capacity to enhance systemic anti-tumor responses via active or passive immunomodulation. Compared to traditional therapies, immunotherapy offers distinct advantages such as broad applicability, rapid therapeutic onset, and reduced adverse effects. However, critical challenges persist in clinical implementation, particularly concerning treatment safety and efficacy optimization. Current limitations, including drug off-target effects and biological delivery barriers, frequently result in suboptimal therapeutic outcomes and severe complications such as autoimmune disorders and nonspecific inflammation. Recently advancements in drug delivery systems (DDS) present transformative solutions to these challenges. Sophisticated DDS platforms enable precise spatiotemporal delivery of tumor antigens, immunotherapeutic agents, and immunostimulatory molecules, thereby achieving targeted modulation of diverse immune cell populations. This technological innovation not only enhances therapeutic efficacy but also significantly mitigates adverse reactions, while facilitating synergistic combinations with conventional cancer treatments. In this review, we outline the application of new drug delivery platforms in major malignancies (including but not limited to melanoma, non-small cell lung cancer, hormone receptor-positive breast cancer, and hepatocellular carcinoma). We further propose evidence-based optimization strategies for next-generation delivery platforms, aiming to bridge the gap between preclinical development and clinical implementation in cancer immunotherapy.