Background Since the beginning of the COVID-19 pandemic, several variants of concern (VOC) have emerged for which there is evidence of an increase in transmissibility, more severe disease, and/or reduced vaccine effectiveness. Effective COVID-19 vaccine strategies are required to achieve broad protective immunity against current and future VOC.Methods We conducted immunogenicity and challenge studies in macaques and hamsters using a bivalent recombinant vaccine formulation containing the SARS-CoV-2 prefusion-stabilized Spike trimers of the parental D614 and the Beta (B.1.351) strains with AS03 adjuvant (CoV2 preS dTM-AS03) in a primary immunization setting. Results We show that a primary immunization with the bivalent CoV2 preS dTM-AS03 elicits broader and durable neutralizing antibody responses against VOC including Omicron BA.1, and SARS-CoV-1 as compared to the parental D614 or Beta variant monovalent vaccines in naïve non-human primates. In addition, the bivalent formulation confers protection against viral challenge with SARS-CoV-2 parental D614G strain as well as Alpha and Beta variant strains in hamsters. Conclusions Our findings demonstrate the potential of a Beta-containing bivalent CoV2 preS dTM-AS03 formulation to provide broad and stable immunogenicity, as well as protection against VOC in naïve populations.

Background Since the beginning of the COVID-19 pandemic, several variants of concern (VOC) have emerged for which there is evidence of an increase in transmissibility, more severe disease, and/or reduced vaccine effectiveness. Effective COVID-19 vaccine strategies are required to achieve broad protective immunity against current and future VOC. Methods We conducted immunogenicity and challenge studies in macaques and hamsters using a bivalent recombinant vaccine formulation containing the SARS-CoV-2 prefusion-stabilized Spike trimers of the ancestral D614 and the variant Beta strains with AS03 adjuvant (CoV2 preS dTM-AS03) in a primary immunization setting. Results We show that a primary immunization with the bivalent CoV2 preS dTM-AS03 elicits broader and durable (1 year) neutralizing antibody responses against VOC including Omicron BA.1 and BA.4/5, and SARS-CoV-1 as compared to the ancestral D614 or Beta variant monovalent vaccines in naïve non-human primates. In addition, the bivalent formulation confers protection against viral challenge with SARS-CoV-2 prototype D614G strain as well as Alpha and Beta variant strains in hamsters. Conclusions Our findings demonstrate the potential of a Beta-containing bivalent CoV2 preS dTM-AS03 formulation to provide broad and durable immunogenicity, as well as protection against VOC in naïve populations.

Ocular surface diseases, including conjunctivitis, are recognized as a common comorbidity in atopic dermatitis (AD) and also occur at an increased frequency in AD patients treated with biologics targeting interleukin-4 receptor alpha (IL-4Ra) or IL-13. However, the inflammatory mechanisms underlying this pathology are unknown. Here, we developed a novel mouse model of skin inflammation-evoked conjunctivitis and showed that it is dependent on CD4+ T cells and basophils. Blockade of IL-4Ra partially attenuated conjunctivitis development, downregulated basophil activation and led to a reduction in expression of genes related to type 2 cytokine responses. Together, these data suggest that an IL-4Ra-basophil axis plays a role in the development of murine allergic conjunctivitis. Interestingly, we found a significant augmentation of a number of genes that encode tear proteins and enzymes in anti-IL-4Ra-treated mice, which may underlie the partial efficacy in this model and may represent candidate mediators of the increased frequency of conjunctivitis following dupilumab in AD patients.