Immunogenicity and Safety Study of GlaxoSmithKline (GSK) Biologicals' Influenza Vaccine(s) GSK3277510A and GSK3277509A in Adults 18 to 60 Years of Age

Inclusion Criteria:

• Male or female adults who are 18 to 60years 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 screening safety laboratory tests that figure in eligibility assessment must be within reference ranges before dosing.
• Female subjects of non-childbearing potential may be enrolled in the study.

• 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.