Lazarus R, Baos S, Cappel-Porter H, et al. - Whether it is safe to administer ChAdOx1 or BNT162b2 concomitantly with an age-appropriate influenza vaccine, was examined in this multicenter, randomized, controlled, phase 4 trial.

• Researchers randomly assigned adults in receipt of a single dose of ChAdOx1 or BNT162b2 (1:1) to receive concomitant administration of either an age-appropriate influenza vaccine or placebo alongside their second dose of COVID-19 vaccine.

• The group who received placebo was administered the influenza vaccine, and vice versa, after 3 weeks.

• In the following manner, recruitment of a total of 679 participants was done to one of six cohorts: 129 ChAdOx1 plus cellular quadrivalent influenza vaccine, 139 BNT162b2 plus cellular quadrivalent influenza vaccine, 146 ChAdOx1 plus MF59C adjuvanted, trivalent influenza vaccine, 79 BNT162b2 plus MF59C adjuvanted, trivalent influenza vaccine, 128 ChAdOx1 plus recombinant quadrivalent influenza vaccine, and 58 BNT162b2 plus recombinant quadrivalent influenza vaccine.

• No safety concerns were raised in correlation with concomitant vaccination with ChAdOx1 or BNT162b2 plus an age-appropriate influenza vaccine. Antibody responses to both vaccines were preserved.

• Concomitant vaccination with the two vaccines over the next immunization season should aid in lowering the burden on healthcare services for vaccine delivery and facilitate timely vaccine administration and protection from COVID-19 and influenza for those in need.