Molecular therapy. Nucleic acidsMar 20, 2026

Using mRNA lipid nanoparticles to deliver antibodies protects against COVID-19 and flu

mRNA Technology Weekly Brief ↗PubMed ↗DOI ↗

Updated Jun 27, 2026

Abstract

Essence

mRNA lipid nanoparticles produced antiviral monoclonal antibodies in mice, but protection varied by virus model and immune response against the encoded antibody.

Evidence

This in vivo mouse study compared recombinant protein antibody infusion with intravenous or intramuscular mRNA/LNP delivery of neutralizing antibodies against SARS-CoV-2 or influenza.

Caveat

Anti-drug antibody responses shortened mRNA-delivered antibody persistence and compromised protection against SARS-CoV-2 Omicron BA.1, while influenza protection was stronger than equivalent recombinant protein doses.

Simplified

Monoclonal antibodies (mAbs) are an emerging class of therapeutics for the prevention and treatment of viral infections. Recent advances in mRNA/lipid nanoparticle (LNP) technology provide a promising new modality for the production of mAbs, potentially bypassing the need for recombinant manufacturing of mAb proteins. In this study, we compared traditional infusion of protein-based neutralizing mAbs targeting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or influenza viruses to mRNA/LNP-based production of mAbs in treated mice. High serum concentrations of mAbs were achieved upon delivery of a single mRNA encoding both heavy and light chains via intravenous or intramuscular routes using prototypic LNP formulations. However, the pharmacokinetics of mRNA-delivered mAbs were heavily influenced by the induction of anti-drug antibody responses directed against the encoded mAbs, resulting in reduced half-lifeand compromised protective capacity against SARS-CoV-2 Omicron BA.1 infection. In contrast, mRNA/LNP delivery of a neutralizing mAb conferred superior protection against lethal influenza challenge compared to equivalent recombinant protein doses. Overall, mRNA/LNP delivery comprises a feasible and attractive pathway to speed the development and deployment of antiviral antibodies. However, optimization of LNP formulation, dosing, and administration routes is required to maximize protective potential. in vivo in vivo