A Study to Evaluate the Efficacy of MEDI7510 in Older Adults

A Phase 2b, double-blind, randomized, and controlled study to evaluate the efficacy of MEDI7510 in approximately 1,900 adult participants, globally, 60 years or older. Participants will be randomized in a 1:1 ratio to receive a single intramuscular dose of each of 2 study vaccines in contralateral arms: MEDI7510 + IIV or placebo + IIV in Season 1. Participants who receive MEDI7510 in the Northern Hemisphere will be re-randomized and blinded in Season 2 to receive either MEDI7510 + IIV or placebo + IIV in a 1:1 ratio. Clinical efficacy will not be assessed in Season 2; however the safety of revaccination will be assessed in Season 2.