A Study to Evaluate a Range of Dose Levels and Vaccination Intervals of Ad26.COV2.S in Healthy Adults and Adolescents
Condition: Healthy
Intervention: Ad26.COV2.S; Placebo
Intervention description: All participants, both adults and adolescents, will receive intramuscular (IM) injections of Ad26.COV2.S.; Adult participants in Groups 4, 5, 6, 8, and 10, and adolescent participants in Group C will receive at least one injection of placebo.
Phase: Phase 2
Study type: Interventional
Primary purpose: Prevention
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Enrollment: 635.0
Sex: All
Minimum age: 12 Years
Healthy volunteers: Accepts Healthy Volunteers

Summary:

      The primary purpose of this study is to assess humoral immune responses of 3 dose levels of
      Ad26.COV2.S administered intramuscularly (IM) as a 2-dose schedule (56 days apart);
      Ad26.COV2.S administered IM as a single vaccination; safety and reactogenicity of Ad26.COV2.S
      administered IM as a 2-dose or a single-dose schedule in adults (18-65 years or older) and to
      assess the safety and reactogenicity of Ad26.COV2.S, administered IM as single dose in
      adolescents (12-17 years) and to test both compressed and expanded 2-dose schedules of
      Ad26.COV2.S (28 and 84 days apart) in adults (18-55 years and 65 years or older).
    

Eligibility criteria:

        Inclusion Criteria:

        For Adults

          -  Participant must have a body mass index (BMI) less than (<) 30.0 kilogram per meter
             square (kg/m^2)

          -  Participant is 18 to 55 years of age, inclusive, or 65 years of age or older on the
             day of signing the informed consent form (ICF).

          -  Participant 18 to 55 years of age, inclusive: participant must be healthy, in the
             investigator's clinical judgment, as confirmed by medical history, physical
             examination, and vital signs performed at screening, and must not have comorbidities
             related to an increased risk of severe coronavirus disease-2019 (COVID-19), except for
             smoking and mild hypertension, which are allowed. Participant 65 years of age and
             older: In the investigator's clinical judgment, participant must be either in good or
             stable health. Participant may have underlying illnesses, as long as the symptoms and
             signs are medically controlled and not considered to be comorbidities related to an
             increased risk of severe COVID-19, except for smoking and mild hypertension, which are
             allowed. If on medication for a condition, the medication dose must have been stable
             for at least 12 weeks preceding vaccination and expected to remain stable for the
             duration of the study. Participant will be included on the basis of physical
             examination, medical history, and vital signs

          -  Participant will be included on the basis of physical examination, medical history,
             and vital signs

          -  All participants of childbearing potential must: a) Have a negative highly sensitive
             urine pregnancy test at screening, b)Have a negative highly sensitive urine pregnancy
             test immediately prior to each study vaccine administration

          -  Participant agrees to not donate bone marrow, blood, and blood products from the first
             study vaccine administration until 3 months after receiving the last dose of study
             vaccine

          -  Participant must be willing to provide verifiable identification, has means to be
             contacted and to contact the investigator during the study

        For Adolescents:

          -  Participant is 12 to 17 years of age, inclusive, on the day of signing the informed
             consent form (ICF)

          -  Participants must have signed an ICF (or their legally acceptable representative or
             parent(s) [preferably both parents if available or as per local requirements] must
             sign) indicating that they understand the purpose of, and procedures required for, the
             study, are willing/able to adhere to the prohibitions and restrictions specified in
             the protocol and study procedures, and are willing (or the parents are willing for
             their adolescent) to participate in the study. Informed assent must be obtained from
             adolescents, depending on local regulations and practice

          -  Participant must be healthy, in the investigator's clinical judgment, as confirmed by
             medical history, physical examination, and vital signs performed at screening, and
             must not have comorbidities related to an increased risk of severe COVID-19

        Exclusion Criteria:

        For Adults

          -  Participant has a clinically significant acute illness (this does not include minor
             illnesses such as diarrhea or mild upper respiratory tract infection) or temperature
             greater than or equal to (>=) 38.0 degree Celsius [C] (100.4 degree Fahrenheit [F])
             within 24 hours prior to the planned first dose of study vaccine; randomization at a
             later date is permitted at the discretion of the investigator and after consultation
             with the sponsor

          -  Participant has a 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 a known or suspected allergy or history of anaphylaxis or other
             serious adverse reactions to vaccines or their excipients (including specifically the
             excipients of the study vaccine)

          -  Participant received treatment with immunoglobulins in the 3 months or blood products
             in the 4 months before the planned administration of the first dose of study vaccine
             or has any plans to receive such treatment during the study

          -  Participant received an investigational drug (including investigational drugs for
             prophylaxis of COVID-19) or used an invasive investigational medical device within 30
             days or received investigational Ig or monoclonal antibodies within 3 months, or
             received convalescent serum for COVID-19 treatment within 4 months or received an
             investigational vaccine (including investigational Adenoviral-vectored vaccines)
             within 6 months before the planned administration of the first dose of study vaccine
             or is currently enrolled or plans to participate in another investigational study
             during the course of this study For Adolescents

          -  Participant has a known or suspected allergy or history of anaphylaxis or other
             serious adverse reactions to vaccines or their excipients (including specifically the
             excipients of the study vaccine)

          -  Participants with a history of illness or with an ongoing illness that, in the opinion
             of the investigator, may pose additional risk to the participant if he/she
             participates in the study

          -  Participant has a history of Kawasaki disease

          -  Participant has a history of an underlying clinically significant acute or chronic
             medical condition or physical examination findings for which, in the opinion of the
             investigator, participation would not be in the best interest of the participant
             (example, compromise the well-being) or that could prevent, limit, or confound the
             protocol-specified assessments