Study to Assess the Immunogenicity and Safety of GSK's Investigational Vaccine (GSK3277511A) When Given to Healthy Smokers and Ex-smokers After Administration of Shingrix Vaccine

Inclusion Criteria: * Subjects who, in the opinion of the investigator, can and will comply with the requirements of the protocol (e.g. completion of the diary cards, return for follow-up visits). * Written informed consent obtained from the subject prior to performance of any study specific procedure. * A male or female between, and including, 50 years and 80 years of age at the time of the first vaccination. * Healthy subjects as established by medical history and clinical examination before entering into the study. * Current or former smoker with a cigarette smoking history ≥10 pack-years. * Female subjects of non-childbearing potential may be enrolled in the study. Non-childbearing potential is defined as pre-menarche, current bilateral tubal ligation or occlusion, hysterectomy, bilateral 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 vaccination, and; has a negative pregnancy test on the day of vaccination, and; has agreed to continue adequate contraception during the entire treatment period and for 2 months after completion of the vaccination series. Exclusion Criteria: * Medical conditions * Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination (no laboratory testing required). * History of potential immune-mediated disease (pIMD). Note: If the subject has any condit…