Abstract
Early life SARS-CoV-2 vaccination has the potential to provide lifelong protection and achieve herd immunity. To evaluate SARS-CoV-2 infant vaccination, we immunized two groups of 8 infant rhesus macaques (RMs) at weeks 0 and 4 with stabilized prefusion SARS-CoV-2 S-2P spike (S) protein, either encoded by mRNA encapsulated in lipid nanoparticles (mRNA-LNP) or mixed with 3M-052-SE, a TLR7/8 agonist in a squalene emulsion (Protein+3M-052-SE). Neither vaccine induced adverse effects. High magnitude S-binding IgG and neutralizing infectious dose 50 (ID50) >103 were elicited by both vaccines. S-specific T cell responses were dominated by IL-17, IFN-γ, or TNF-α. Antibody and cellular responses were stable through week 22. The S-2P mRNA-LNP and Protein-3M-052-SE vaccines are promising pediatric SARS-CoV-2 vaccine candidates to achieve durable protective immunity.
One-Sentence Summary SARS-CoV-2 vaccines are well-tolerated and highly immunogenic in infant rhesus macaques
Competing Interest Statement
A. Carfi, and D. Edwards are employees of Moderna Inc. and hold equities from the company. B. S. Graham and K. S. Corbett are inventors on Patent Applications: EP Patent Application 17800655.7 filed 13 May 2019, entitled Prefusion coronavirus spike proteins and their use; US Patent Application 16/344,774 filed 24 April 2019 entitled Prefusion coronavirus spike proteins and their use [HHS Ref. No. E-234-2016-1-US-03]. O. M. Abiona, B. S. Graham and K. S. Corbett are inventors on the Patent Application: US Provisional Patent Application 62/972,886 filed 11 February 2020 entitled 2019-nCoV Vaccine. Dr. Permar has sponsored programs and consults with Merck and Moderna for their CMV vaccine programs. C.B. Fox is an inventor on US patent application 2017/032756, PEGylated Lysosmes and Methods of Use.