A Study to Evaluate the Safety and Immunogenicity of an Adjuvanted RSV Vaccine in Healthy Older Adults

The study will evaluate the safety, tolerability, and immunogenicity of up to 6 RSV vaccine
formulations, some with adjuvant, when administered alone or concomitantly with SIIV. Healthy
male and female subjects between 60 to 85 years of age will be enrolled. Subjects in the
sentinel cohort will receive one of two RSV vaccine formulations at one of 3 antigen dose
levels or placebo. Subjects in the expanded cohort will receive one of two RSV vaccine
formulations at one of 3 antigen dose levels with or without SIIV.

Inclusion Criteria:

1. Evidence of a personally signed and dated informed consent document (ICD) indicating
that the subject has been informed of all pertinent aspects of the study.

2. Healthy adults who are determined by medical history, physical examination, and
clinical judgment of the investigator to be eligible for inclusion in the study.

3. Willing and able to comply with scheduled visits, vaccination plan, laboratory tests,
and other study procedures.

4. Sentinel-cohort subjects only: Male and nonchildbearing-potential female adults aged
60 to 85 years at the time of enrollment (signing of the ICD).

5. Expanded-cohort subjects only: Male and nonchildbearing-potential female adults aged
65 to 85 years at the time of enrollment (signing of the ICD).

Exclusion Criteria:

1. Sentinel-cohort subjects only: Any screening hematology and/or blood chemistry
laboratory value that meets the definition of a ≥ Grade 1 abnormality.

2. Sentinel-cohort subjects only: Positive test for human immunodeficiency virus
(HIV),hepatitis B surface antigen (HBsAg), hepatitis B core antibodies (HBc Abs), or
hepatitis C virus antibodies (HCV Abs) at the screening visit.

3. Investigator site staff members directly involved in the conduct of the study and
their family members, site staff members otherwise supervised by the investigator, or
subjects who are Pfizer employees, including their family members, directly involved
in the conduct of the study.

4. Participation in other studies involving investigational product within 28 days prior
to study entry and/or during study participation.

5. Known infection with HIV, hepatitis C virus (HCV), or hepatitis B virus (HBV).

6. Previous vaccination with any licensed or investigational RSV vaccine, or planned
receipt throughout the study of nonstudy RSV vaccine.

7. History of severe adverse reaction associated with a vaccine and/or severe allergic
reaction (eg, anaphylaxis) to any component of the investigational product(s), or
history of severe allergic reaction (eg, anaphylaxis) to any substance.

8. Immunocompromised subjects with known or suspected immunodeficiency, as determined by
history and/or laboratory/physical examination.

9. Subjects who receive treatment with immunosuppressive therapy, including cytotoxic
agents or systemic corticosteroids, eg, for cancer or an autoimmune disease, or
planned receipt throughout the study. If systemic corticosteroids have been
administered short term (<14 days) for treatment of an acute illness, subjects should
not be enrolled into the study until corticosteroid therapy has been discontinued for
at least 28 days before investigational product administration. Intra-articular,
intrabursal, or topical (epidural, skin or eyes) corticosteroids are permitted.

10. Subject with a history of autoimmune disease or an active autoimmune disease requiring
therapeutic intervention including but not limited to: systemic or cutaneous lupus
erythematosus, autoimmune arthritis/rheumatoid arthritis, Guillain-Barré
syndrome,multiple sclerosis, Sjögren syndrome, idiopathic thrombocytopenic purpura,
glomerulonephritis, autoimmune thyroiditis, giant cell arteritis (temporal arteritis),
psoriasis, and insulin-dependent diabetes mellitus (type 1).

11. Receipt of blood/plasma products or immunoglobulin, from 60 days before
investigational product administration or planned receipt throughout the study.

12. Other acute or chronic medical or psychiatric condition including recent (within the
past year) or active suicidal ideation or behavior or laboratory abnormality that may
increase the risk associated with study participation or investigational product
administration or may interfere with the interpretation of study results and, in the
judgment of the investigator, would make the subject inappropriate for entry into this
study.

13. Bleeding diathesis or condition associated with prolonged bleeding that would, in the
opinion of the investigator, contraindicate intramuscular injection.

14. Female subjects of childbearing potential; pregnant female subjects; breastfeeding
female subjects; fertile male subjects who are unwilling to use a highly effective
method of contraception for at least 28 days after the last dose of investigational
product.

15. Expanded-cohort subjects only: Vaccination with any influenza vaccine within 6 months
(182 days) before investigational product administration.

16. Expanded-cohort subjects only: Allergy to egg proteins (egg or egg products) or
chicken proteins.