IVT-free, chemically synthesized protein-encoding RNA oligonucleotides for rapid production of personalized cancer vaccines

Abstract

Significance Personalized mRNA cancer vaccines hold great therapeutic promise, yet their production depends on multistep in vitro transcription (IVT) that generates immunogenic dsRNA impurities and prolongs manufacturing to nearly three months, often missing the optimal therapeutic window. Here, we introduced a cap-independent translation enhancer BBV and developed protein-encoding RNA oligonucleotides (PEOs), which were chemically synthesized RNAs bearing 5’-OH and 3’-P termini that drive rolling circle translation after endogenous circularization. PEOs contain undetectable dsRNA and exhibit minimal immunogenicity. In melanoma and orthotopic glioma models, PEO vaccines significantly inhibited tumor growth and synergized with anti-PD-1 therapy. In conclusion, this proof-of-concept study built an IVT-free platform for rapid, safe, and highly druggable vaccines.