 Spinal cord injuries, SCIs, can be devastating and lead to significant disability and financial burden on both patients and society. Transplanting cells, growth factors, enzyme drugs, and microRNAs have been used to treat SCIs, but these therapies face many challenges due to the complex environment created by the injury. Biomaterial-based defenders, BBDs, which are designed to protect the transplants from the destructive components of the environment have shown promising results in increasing the survival rate of transplants and retaining the activity of proteins and nucleic acids. This review discusses the different types of biopharmaceuticals used in treating SCIs and the challenges they face, as well as the potential of BBDs to improve the efficacy of these treatments. This article was authored by Xiong Qi Zhang, Jian Chao, Jia He Wu, and others.