A Study to Evaluate the Safety and Immunogenicity of MEDI7510 in Older Adults

The goal of this study is to evaluate the safety, tolerability and immunogenicity of ascending doses of adjuvant in combination with a single dosage level of RSV sF in adults 60 years or older who are healthy or who have stable, chronic underlying medical conditions. This study will also provide preliminary safety and immunogenicity data to support concurrent dosing of MEDI7510 with influenza vaccine (IIV), and to assess the safety of MEDI7510 at a dose previously assessed in the Phase 1a study.

A Phase 1b, double-blind, randomized, controlled cohort escalation study evaluating the safety, tolerability and immunogenicity of MEDI7510. Approximately 264 subjects will be enrolled at approximately 5 study centers in the US and randomized by cohort (Cohort 1 \[4:1\]; Cohorts 2 and 3 \[8:8:3\]; Cohort 4 \[5:1\]) to receive a single intramuscular dose of 1 study vaccine (Cohorts 1 and 4) or a single intramuscular dose of each of 2 study vaccines (Cohorts 2 and 3) administered in contralateral arms. Cohort 1: MEDI7510 formulation (n = 40) or IIV (n = 10) Cohort 2: MEDI7510 formulation and placebo (n = 40) or MEDI7510 formulation and IIV (n = 40) or placebo and IIV (n = 15) Cohort 3: MEDI7510 formulation and placebo (n = 40) or MEDI7510 formulation and IIV (n = 40) or placebo and IIV (n = 15) Cohort 4: MEDI7510 formulation (n = 20) or IIV (n = 4)