Severe acute respiratory syndrome coronavirus(-2) (SARS CoV-2) is a highly transmissible and pathogenic coronavirus that has spread rapidly and globally and Influenza is a worldwide public health problem, responsible for significant morbidity and mortality. Ad26.COV2.S (also known as VAC31518, JNJ-78436735) is a monovalent vaccine composed of a recombinant, replication-incompetent human adenovirus type 26 (Ad26) vector, constructed to encode SARS-CoV-2 spike (S) protein, stabilized in its prefusion conformation. The seasonal influenza vaccines to be used in this study are quadrivalent (standard dose) and quadrivalent (high-dose) or equivalent formulated. The aim is to demonstrate the concomitant administration of the Ad26.COV2.S vaccine and a seasonal quadrivalent influenza vaccine (standard-dose) is non-inferior than the administration of either seasonal quadrivalent influenza vaccine (standard-dose) alone as measured by HI titers against each of the 4 influenza vaccine strains at 28 days after the administration of a quadrivalent seasonal influenza vaccine or Ad26.COV2.S vaccine alone as measured by Spiked-Enzyme-linked Immunosorbent Assay (S-ELISA) antibody titers at 28 days after the administration of the Ad26.COV2.S vaccine. This study consists of 3 phases: screening phase (Day -28 to 1), treatment phase (vaccination visits on Days 1 and 29), and a follow-up phase (28 days after each vaccination). Some of safety assessments will include physical examination, vital signs, clinical safety laboratory assessments, pregnancy testing, monitoring of adverse events (AEs), serious adverse events (SAEs), and adverse events of special interest (AESI). The total duration of the study is up to 7-8 months.
The purpose of this study is to demonstrate the non-inferiority (NI) of the humoral immune response of the 4 influenza vaccine strains after concomitant administration of the Ad26.COV2.S vaccine and a seasonal quadrivalent standard-dose influenza vaccine versus the administration of a seasonal quadrivalent standard-dose influenza vaccine administered alone; and to demonstrate the NI of the binding antibody response after concomitant administration of Ad26.COV2.S vaccine and a seasonal quadrivalent standard-dose influenza vaccine versus the administration of Ad26.COV2.S vaccine administered alone.