Ad26.COV2.S and SARS-CoV-2 spike protein ferritin nanoparticle vaccine protect against SARS-CoV-2 Omicron BA.5 challenge in macaques.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines demonstrate reduced protection against acquisition of BA.5 subvariant but are still effective against severe disease. However, immune correlates of protection against BA.5 remain unknown. We report the immunogenicity and protective efficacy of vaccine regimens consisting of the vector-based Ad26.COV2.S vaccine and the adjuvanted spike ferritin nanoparticle (SpFN) vaccine against a high-dose, mismatched Omicron BA.5 challenge in macaques. The SpFNx3 and Ad26 + SpFNx2 regimens elicit higher antibody responses than Ad26x3, whereas the Ad26 + SpFNx2 and Ad26x3 regimens induce higher CD8 T cell responses than SpFNx3. The Ad26 + SpFNx2 regimen elicits the highest CD4 T cell responses. All three regimens suppress peak and day 4 viral loads in the respiratory tract, which correlate with both humoral and cellular immune responses. This study demonstrates that both homologous and heterologous regimens involving Ad26.COV2.S and SpFN vaccines provide robust protection against a mismatched BA.5 challenge in macaques.
Competing Interests: Declaration of interests D.H.B. is a co-inventor on provisional vaccine patents licensed to Janssen (63/121,482; 63/133,969; 63/135,182) and serves as a consultant to Pfizer. M.G.J. and K.M. are co-inventors on international patent application WO/2021/178971 A1 entitled “Vaccines against SARS-CoV-2 and other coronaviruses.” M.G.J. is a co-inventor on international patent application WO/2018/081318 and a US patent 10,960,070 entitled “Pre-fusion coronavirus spike proteins and their use.” K.M.’s current affiliation is Pfizer.
(Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)