A Single Ascending Dose Study in Adults (Stage 1) and Single Ascending Dose-Finding Study (Stage 2) in Elderly Subjects With ASP3772, A Pneumococcal Vaccine

The study population will consist of 3 different groups: Group 1 - Stage 1 PCV13 naïve
participants randomized within 3 sequential cohorts to ASP3772 or PCV13; Group 2 - Stage 2
PCV13 naïve participants randomized within 3 sequential cohorts to ASP3772 or PCV13; and
Group 3 - Stage 2 participants previously vaccinated with PCV13 that will receive PPSV23.

Inclusion Criteria:

- Stage 1: Subject is healthy male or female between 18 and 64 year of age inclusive, at
screening.

- Stage 2: Subject is a male or female between 65 and 85 years of age, inclusive, at
screening who is healthy or has chronic controlled, stable disease with no change in
disease severity, medical therapy and no hospitalization records in last 12 weeks as
determined by medical history, physical examination and laboratory data.

- A female subject is eligible to participate if not pregnant and at least 1 of the
following conditions applies:

- Not a woman of childbearing potential (WOCBP) OR

- WOCBP who agrees to follow the contraceptive guidance at screening and for at
least 28 days after the study vaccine administration.

- Female subject must agree not to breastfeed starting at screening and for 28 days
after the study vaccine administration.

- Female subject must not donate ova starting at screening and for 28 days after the
study vaccine administration.

- A male subject with female partner(s) of childbearing potential must agree to use
contraception at screening and for at least 28 days after the study vaccine
administration.

- Male subject must not donate sperm starting at screening and for 90 days after the
study vaccine administration.

- Male subject with a pregnant or breastfeeding partner(s) must agree to remain
abstinent or use a condom for the duration of the pregnancy or time partner is
breastfeeding at screening and for 28 after the study vaccine administration.

- Subject agrees not to participate in another interventional study while participating
in the present study.

Exclusion Criteria:

- Subject has a known or suspected hypersensitivity to ASP3772, its comparators or any
components of the formulations used.

- Subject has had previous exposure with ASP3772.

- Subject has received PPSV23 within the last 5 years.

- Subject has received PCV13 or any other licensed or investigational pneumococcal
vaccine (except for PPSV23, which is acceptable if given more than 5 years prior to
study enrollment) at any time. (Note: This exclusion criterion is not applicable to
Group 3; those subjects 65 to 85 years of age who previously received immunization
with PCV13. Prior PCV13 immunization should have taken place no less than 10 months
and no more than 2 years prior to study vaccine administration. These subjects are
eligible to be enrolled in the nonrandomized arm of Stage 2, Group 3.

- Subject has a history of microbiologically-proven invasive disease caused by S.
pneumoniae.

- Subject has an immune disorder(s) (including autoimmune disease) and/or clinical
conditions requiring immunosuppressive drugs.

- Subject has any evidence of any unstable or active clinically significant
cardiovascular, gastrointestinal, endocrine, hematologic, hepatic, immunologic,
metabolic, urologic, pulmonary, neurologic, dermatologic, psychiatric, renal and/or
other major disease or malignancy, e.g., uncontrolled hypertension, uncontrolled
diabetes, heart failure, uncontrolled chronic obstructive pulmonary disease, end-stage
renal disease.

- Subject has history of illicit drug(s) or alcohol abuse that will interfere with the
protocol requirements and/or a positive urine drug test (for Stage 1 subjects only) at
screening.

- Subject has any clinically significant history of allergic conditions including drug
allergies, asthma or anaphylactic reactions, but excluding untreated asymptomatic
seasonal allergies prior to study vaccine administration.

- Subject has a coagulation disorder contraindicating intramuscular immunization.

- Subject has a positive serology test for hepatitis B surface antigen (HBsAg),
hepatitis B core antibody (anti-HBc), hepatitis A virus antibodies (immunoglobulin M),
hepatitis C virus antibodies (anti-HCV) or antibodies to human immunodeficiency virus
(HIV) type 1 and/or type 2 at screening.

- Subject has/had febrile illness (> 100.4°F oral equivalent) or symptomatic, viral,
bacterial (including upper respiratory infection) or fungal (noncutaneous) infection
within 1 week prior to day 1.

- Subject has any clinically significant abnormality from the physical examination, ECG
and clinical laboratory tests during screening.

- Subject is unlikely to adhere to study procedures, keep appointments, is planning to
relocate during the study or cannot be adequately followed for safety according to the
protocol.

- Subject has any other condition, which precludes the subject's participation in the
study.

- Subject has received any vaccines within 30 days prior of receipt of the study vaccine
(exception: Influenza virus vaccine given according to recommended guidelines must be
given at least 7 days prior to receiving study vaccine).

- Subject has had significant blood loss, donated 1 unit (450 mL or more) or received
transfusion of any blood or blood products within 60 days or donated plasma within 7
days prior to day 1.