Figure 1.

Study design. Relevant points in the study timeline are designated as day (D) and month (M). N indicates number of participants in each study part/group. Dose 1 and 2 indicate vaccine and placebo administration timepoints. Blood sample S was the blood sample drawn for analysis of hematological (blood cell counts and hemoglobin levels) and biochemical (alanine and aspartate aminotransferases, creatinine, blood urea nitrogen, and uric acid) laboratory parameters. Blood sample H was the blood sample collected to measure concentrations of RSVPreF3-specific immunoglobulin and titers of respiratory syncytial virus-specific neutralizing antibodies. Blood sample C was the blood sample collected for analysis of polyfunctional T-cell responses. 30 μg, 60 μg, and 120 μg indicate RSVPreF3 antigen concentration. Abbreviations: AS01_B and AS01_E, adjuvanted vaccine formulations with the corresponding vaccine adjuvant systems; IDMC, independent data monitoring committee; Plain, unadjuvanted vaccine formulations; RSVPreF3, prefusion conformation of the respiratory syncytial virus F protein.