Study of a Respiratory Syncytial Virus/Human Metapneumovirus/Parainfluenza Virus Type 3 Vaccine Candidate in Adults Aged 60 Years and Older

A Phase 1, Dose-Escalation, Randomized, Active-Controlled, Modified Double-Blind, Parallel-Group, Multi-Arm Study to Investigate the Safety and Immunogenicity of a Combined Respiratory Syncytial Virus/Human Metapneumovirus/Parainfluenza Virus Type 3 Vaccine Candidate in Adult Participants Aged 60 Years and Older

The purpose of this phase 1 study is to evaluate whether the vaccine is safe and can help the body to develop germ fighting agents called "antibodies" (immunogenicity) against the respiratory syncytial virus (RSV), human metapneumovirus (hMPV), and parainfluenza virus type 3 (PIV3). The study will use different doses of PIV3 only and different combinations of RSV/hMPV/PIV3 or RSV/hMPV or only RSV vaccine in adults aged 60 years and older.

The study duration will be up to approximately 12 months minus the screening period.

Inclusion Criteria:

• Aged 60 years or older on the day of inclusion (means from the means from the day of the 60th birthday).
• Informed consent form (ICF) has been signed and dated
• A female participant is eligible to participate if she is of non-childbearing potential. To be considered of non-childbearing potential, a female must be postmenopausal for at least 1 year, or surgically sterile.

Exclusion Criteria:

Participants are excluded from the study if any of the following criteria apply:

-Any condition which, in the opinion of the Investigator, might interfere with the evaluation of the study objectives.

Note: The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.