A Study to Evaluate the Safety, Tolerability and Immunogenicity of Two Vaccinations of Ad26.RSV.preF One Year Apart in Adults Aged 60 Years and Older in Stable Health

Inclusion Criteria:

- Each participant must sign an informed consent form (ICF) indicating that he or she
understands the purpose of and procedures required for the study, is willing to
participate in the study and attend all scheduled visits, and is willing and able to
comply with all study procedures and adhere to the prohibitions and restrictions
specified in this protocol

- Before randomization, a woman must be: postmenopausal - A postmenopausal state is
defined as no menses for 12 months without an alternative medical cause; and not
intending to conceive by any methods

- From the time of first vaccination until 3 months after the first dose of study
vaccine, and from the second vaccination through 3 months after, a man who has not had
a vasectomy (or if a vasectomy was performed less than 1 year ago and the absence of
sperm cannot be verified)

- In the investigator's clinical judgment, participant must be either in good or stable
health. Participants may have underlying illnesses such as hypertension, type 2
diabetes, hyperlipoproteinemia, or hypothyroidism, as long as their symptoms/signs are
medically controlled. If they are on medication for a condition, the medication dose
must have been stable for at least 12 weeks preceding vaccination and expected to
remain stable for the duration of the study. Participants will be included on the
basis of physical examination, medical history, vital signs, and 12-lead
electrocardiogram (ECG) performed at screening

- Participant must be healthy on the basis of clinical laboratory tests performed at
screening. If the results of the laboratory screening tests are outside the central
laboratory normal reference ranges and additionally within the limits of toxicity
Grades 1 or 2 according to the US Food and Drug Administration (FDA) toxicity tables
(for tests in the FDA table ), the participant may be included only if the
investigator judges the abnormalities or deviations from normal to be not clinically
significant and appropriate and reasonable for the population under study. This
determination must be recorded in the participant's source documents and initialed by
the investigator

Exclusion Criteria:

- Participant has acute illness (this does not include minor illnesses such as diarrhea)
or temperature greater than or equal to (>=) 38.0 degree celsius within 24 hours prior
to the first dose of study vaccine; enrollment at a later date is permitted

- Participant has a serious chronic disorder, including severe chronic obstructive
pulmonary disease or clinically significant congestive heart failure, requirement for
supplemental oxygen, end stage renal disease with or without dialysis, clinically
unstable cardiac disease, Alzheimer's disease, or has any condition for which, in the
opinion of the investigator, participation would not be in the best interest of the
participant (for example, compromise well-being) or that could prevent, limit, or
confound the protocol-specified assessments

- Participant has had major surgery within the 4 weeks prior to randomization or has
planned major surgery through the course of the study

- Participant has chronic active hepatitis B or hepatitis C infection, documented by
hepatitis B surface antigen and hepatitis C antibody, respectively

- Participant has human immunodeficiency virus (HIV) type 1 or type 2 infection