Trial to Evaluate the Safety and Immunogenicity of 3 Lots of 20-valent Pneumococcal Conjugate Vaccine in Pneumococcal Vaccine-Naïve Adults

Inclusion Criteria:

1. Male or female adults ≥18 and <50 years of age.

2. Adults determined by clinical assessment, including medical history and clinical
judgment, to be eligible for the study, including adults with preexisting stable
disease, defined as disease not requiring significant change in therapy in the
previous 6 weeks or hospitalization for worsening disease within 12 weeks before
receipt of investigational product.

3. Female subject of childbearing potential or male subject who is able to father
children, and willing to use a highly effective method of contraception as outlined in
this protocol for at least 28 days after the dose of investigational product; or
female subject not of childbearing potential or male subject not able to father
children.

Exclusion Criteria:

1. Previous vaccination with any licensed or investigational pneumococcal vaccine, or
planned receipt through study participation.

2. Serious chronic disorder including metastatic malignancy, severe chronic obstructive
pulmonary disease (COPD) requiring supplemental oxygen, end-stage renal disease with
or without dialysis, clinically unstable cardiac disease, or any other disorder that,
in the investigator's opinion, excludes the subject from participating in the study.

3. History of microbiologically proven invasive disease caused by S pneumoniae.

4. Pregnant female subjects or breastfeeding female subjects (known or suspected).