LAUSR

The effect of protein drugs is always limited by their relatively low stability and fast degradation property; thus, various elegant efforts have been made to improve the bioactivity and biocompatibility of the protein drugs. Here, an alternative way is proposed to solve this problem. By simply adding a limited amount of small‐molecular regulator, which tunes the subtle balance of protein–protein interactions (PPIs) and disulfide bond formation, the self‐assembly property of the protein drug can be regulated, forming an “active protein material” itself. This means that, the resulting biomaterial is dominated by the protein drug and water, with significantly enhanced bone regeneration effect compared to the virgin protein in vitro and in vivo, through multivalent effect between the protein and receptor and the retarded degradation of the assembled proteins. In this active protein material, the protein drug is not only the active drug, but also the drug carrier, which greatly increases the drug‐loading efficiency of the biomaterial, indicating the advantages of the easy preparation, high efficiency, and low cost of the active protein material with a bright future in biomedical applications.