A Study to Evaluate the Safety and Immunogenicity of a Candidate Ebola Vaccine in Adults

Inclusion Criteria

• Subjects who, in the opinion of the Investigator, can and will comply with the requirements of the protocol (e.g. capability of or availability for Diary Card completion, return for follow-up visits, availability for clinical follow-up throughout the study period).
• Written/ thumb printed informed consent obtained from the subject prior to performing any study specific procedure or written/ thumb printed informed consent obtained from the subject's parent(s)/ legally acceptable representative(s) (LAR[s]) and written/ thumb printed informed assent obtained from the subject, for minor subjects. This will only be applicable for countries where the legal age of majority is ≥ 21 years.
• A male or female aged 18 years of age or older at the time of Screening.
• Healthy subjects as per Investigator judgement, as established by medical history, clinical examination and haematology/ biochemistry laboratory parameters screening before entering into the study.
• Female subjects of non-childbearing potential may be enrolled in the study.
• Non-childbearing potential is defined as pre-menarche, current tubal ligation, hysterectomy, ovariectomy or post-menopause.
• Female subjects of childbearing potential may be enrolled in the study, if the subject:
• has practiced adequate contraception for 30 days prior to the Day 0 visit, and
• has a negative pregnancy test at the Day 0 visit, and
• has agreed to continue adequate contraception until 30 days after the Month 6 visit.

Exclusion Criteria

• Use of any investigational or non-registered product (drug or vaccine) other than the study vaccine during the period starting 30 days before the Day 0 visit, or planned use during the study period.
• Previous vaccination with an investigational EBOV or Marburg vaccine, or previous vaccination with a chimpanzee adenoviral vectored investigational vaccine.
• Known prior EBOV or SUDV disease.
• Travel to a country affected by the EBOV epidemic or direct contact with a person with EVD within 21 days prior to the Day 0 visit.
• History of any reaction or hypersensitivity (such as anaphylaxis, urticaria [hives], respiratory difficulty, angioedema, or abdominal pain) likely to be exacerbated by any component of the study vaccine.
• Planned administration/ administration of a vaccine not foreseen by the study protocol in the period starting 30 days before and ending 30 days after each vaccination visit.
• Serious acute or chronic illness determined by medical history and clinical examination including, but not limited to:
• Clinically significant immunosuppressive or immunodeficient condition (e.g. clinical acquired immune deficiency syndrome [AIDS]).
• Any clinically significant haematological (CBC, including differential count and platelet count) or biochemical (ALT, creatinine) laboratory abnormality.
• Any chronic illness with recent signs of exacerbation, or imposing a change in the chronic treatment regimen, within 3 months prior to the Day 0 visit.
• Any unstable chronic medical condition (e.g. uncontrolled asthma).
• Pregnant female.