Researchers reported a novel zwitterionic ionizable lipid for mRNA‑LNP formulations that improved antigen expression while reducing inflammatory reactogenicity in preclinical cancer vaccine models. The lipid chemistry enhanced mRNA delivery efficiency and mitigated common LNP‑associated inflammation, addressing two persistent obstacles for therapeutic mRNA vaccines and immunotherapies. The work, positioned as an advancement in delivery chemistry, could influence next‑generation mRNA vaccines by widening tolerable dosing and improving immunogenicity profiles. The findings are relevant for oncology vaccine developers and for companies advancing therapeutic mRNA beyond infectious disease prophylaxis. Translatability will hinge on manufacturing scalability, regulatory toxicology readouts and human safety data, but the approach offers a tangible path to iterate LNP design for lower reactogenicity without compromising antigen output.