Immunogenicity and Safety Study of GlaxoSmithKline (GSK) Biologicals' Influenza Vaccine(s) GSK3206641A and GSK3206640A Administered in Adults 18 to 64 Years of Age

Inclusion Criteria:

- Male or female adults who are 18 to 64 years of age (inclusive) at the time of first
study vaccination.

- Written informed consent obtained from subject.

- Subjects who the investigator believes can and will comply with the requirements of
the protocol .

- Healthy subjects as established by medical history and physical examination.

- Access to a consistent means of telephone contact.

- For subjects who undergo a screening visit: results of all safety laboratory tests
obtained at the screening visit must be within reference ranges. Results of any
repeat testing cannot be used to qualify a subject for enrolment.

- Female subjects of non-childbearing potential may be enrolled in the study.
Non-childbearing potential is defined as current tubal ligation, hysterectomy,
ovariectomy or post-menopause.

- Female subjects of childbearing potential may be enrolled in the study, if they

- have practiced adequate contraception for 30 days prior to vaccination, and

- have a negative pregnancy test on the day of vaccination, and

- agree to continue to practice adequate contraception until 2 months after the
last dose administered.

Exclusion Criteria:

- Presence or evidence of neurological or psychiatric diagnoses which, although stable,
are deemed by the investigator to render the potential subject unable/unlikely to
provide accurate safety reports.

- Presence or evidence of substance abuse.

- Diagnosed with cancer, or treatment for cancer within three years.

- Diagnosed with excessive daytime sleepiness, or narcolepsy; or history of narcolepsy
in a subject's parent, sibling or child.

- Presence of a temperature ≥ 38.0ºC (≥100.4ºF), or acute symptoms greater than "mild"
severity on the scheduled date of first vaccination.

- Any confirmed or suspected immunosuppressive or immunodeficient condition including
history of human immunodeficiency virus (HIV) infection.

- Receipt of systemic glucocorticoids within 30 days prior to the first dose of study
vaccine/placebo, or any other cytotoxic, immunosuppressive or immune-modifying drugs
within 6 months of first study vaccine/ placebo dose.

- Any significant disorder of coagulation or treatment with warfarin derivatives or
heparin.

- An acute evolving neurological disorder or Guillain Barré Syndrome within 42 days of
receipt of prior seasonal or pandemic influenza vaccine.

- Administration of an inactive vaccine within 14 days or of a live attenuated vaccine
within 30 days before the first dose of study vaccine/placebo.

- Planned administration of any vaccine other than the study vaccine/placebo before
blood sampling at the Day 42 visit.

- Previous administration of any H7 vaccine or physician-confirmed H7 disease.

- Use of any investigational or non-registered product other than the study vaccine
within 30 days preceding the first dose of study vaccine/placebo, or planned use
during the study period.

- Receipt of any immunoglobulins and/or any blood products within 90 days before the
first dose of study vaccine/placebo, or planned administration of any of these
products during the study period.

- Any known or suspected allergy to any constituent of influenza vaccines or component
used in the manufacturing process of the study vaccine including a history of
anaphylactic-type reaction to consumption of eggs; or a history of severe adverse
reaction to a previous influenza vaccine.

- Known pregnancy or a positive urine beta-human chorionic gonadotropin (β-hCG) test
result before the first dose of study vaccine/placebo.

- Lactating or nursing women.

- Any condition which, in the opinion of the investigator, prevents the subject from
participating in the study.