A Study to Evaluate the Safety and Immunogenicity of Seasonal Influenza Vaccine and an Adenovirus Serotype 26- Based Vaccine Encoding for the Respiratory Syncytial Virus Pre-fusion F Protein (Ad26.RSV.preF), With and Without Co-administration, in Adults Aged 60 Years and Older in Stable Health

A Randomized, Double-blind, Placebo-controlled Phase 2a Study to Evaluate the Safety and Immunogenicity of Seasonal Influenza Vaccine and Ad26.RSV.preF, With and Without Co-administration, in Adults Aged 60 Years and Older in Stable Health

The purpose of this study is to demonstrate the non-inferiority of the concomitant administration of an adenovirus serotype 26- based vaccine encoding for the respiratory syncytial virus pre-fusion F protein (Ad26.RSV.preF) and seasonal influenza vaccine versus the administration of seasonal influenza vaccine alone in terms of humoral immune response expressed by the geometric mean titers (GMTs) of hemagglutination inhibition (HI) antibody titers against all four influenza vaccine strains 28 days after the administration of influenza vaccine, and to assess the safety and tolerability of a single dose of 1*10^11 viral particles (vp) of Ad26.RSV.preF, administered intramuscularly to participants aged greater than or equal to 60 years separately or concomitantly with seasonal influenza vaccine.

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:

  1. Postmenopausal (A postmenopausal state is defined as no menses for 12 months without an alternative medical cause) and
  2. Not intending to conceive by any methods

• In the investigator's clinical judgment, participant must be either in good or stable health, and not at risk of serious complications from influenza. 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 (or only small, clinically non-significant changes have been made in the judgement of the Principal Investigator) 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 on Day 1

• From the time of first vaccination through 3 months after the second dose of study vaccine, participant agrees not to donate blood

• Participant must be willing to provide verifiable identification, have means to be contacted and to contact the investigator during the study

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 (ºC) 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 history of malignancy within 5 years before screening (exceptions are squamous and basal cell carcinomas of the skin and carcinoma in situ of the cervix, or malignancy, which is considered cured with minimal risk of recurrence)
• Participant has had major surgery (per the investigator's judgment), within 4 weeks before dosing, or will not have fully recovered from surgery, or has surgery planned during the time the participant is expected to participate in the study or within 6 months after the final dose of study vaccine
• Participant has chronic active hepatitis B or hepatitis C infection, documented by hepatitis B surface antigen and hepatitis C antibody, respectively