Stopping SARS-CoV-2 Viral Transmission? NIAID-Led Scientists’ Mucosal Vaccine Superior to Moderna’s mRNA in Primate Study

National Institutes of Health (NIH) executive-level scientists Daniel Douek and Robert Seder led a team of collaborators from Emory University School of Medicine (Center for Childhood Infections and Vaccines of Children’s Healthcare of Atlanta and Department of Pediatrics) as well as the university’s Emory Vaccine Center and the private contract research organization Bioqual investigating an experimental mucosal vaccine targeting SARS-CoV-2, the virus behind COVID-19. They have embarked on this early stage, preclinical study due to the durability problems with the existing mRNA COVID-19 vaccines developed by Pfizer-BioNTech and Moderna. As TrialSite has reported on for nearly three years now, the current COVID-19 vaccines are limited due to waning effectiveness and an ever-mutating pathogen, thus minimizing protection over time from symptomatic infection. With the advent of the Omicron variant of concern and ensuing upper respiratory impacts, the development of mucosal-based vaccines has been highly sought after. The goal: enhance airway immunity to reduce transmission rates, and corresponding rates of infection. In this preclinical lab-based study the team infected primates with SARS-CoV-2 XBB.1.16, and compared how well the experimental intranasal mucosal vaccine protected such non-human primate subjects already exposed to a two-dose regimen of Moderna’s mRNA-1273 five months post-delivery via intramuscular or mucosal boosting. The authors report that protection in the primates elicited by the aerosolized vaccine was associated with mucosal IgG and IgA responses, whereas protection elicited by intranasal delivery was mediated primarily by mucosal IgA. They conclude that “durable immunity and effective protection against a highly transmissible heterologous variant in both the upper and lower airways can be achieved by mucosal delivery of a virus-vectored vaccine.” TrialSite notes that the NIAID-developed product beat out Moderna’s mRNA jab when measuring sterilizing impact. The NIAID team has filed patents.

The recent study was funded by the Intramural Research Program of the Vaccine Research Center at the National Institute of Allergy and Infectious Diseases (NIAID) of the NIH as well as from the NIAID Centers of Excellence for Influenza and Surveillance, CEIRS, and funds awarded to Emory University among other sources. The study results need peer review.