Safety, Tolerability, and Immunogenicity of MenABCWY Administered on Different Dosing Schedules in Healthy Adolescents

The purpose of this study is to assess the safety, tolerability, and immunogenicity of the combined meningococcal groups A, B, C, W and Y (MenABCWY) vaccine (GSK3536819A) intended to protect against invasive meningococcal disease (IMD) caused by all 5 meningococcal serogroups.

Inclusion Criteria: * Participants or/and participants' parent(s)/Legally Acceptable Representative(s) \[LAR(s)\] who, in the opinion of the investigator, can and will comply, with the requirements of the protocol. * Written or witnessed/thumb printed informed consent obtained from the participant/parent(s)/LAR(s) of the participant prior to performance of any study specific procedure. * Written informed assent obtained from the participant (if applicable) prior to performing any study specific procedure. * A male or female between, and including, 11 and 14 years of age (i.e. 14 years + 364 days) at the time of the first vaccination. * Healthy participants as established by medical history, physical examination and clinical judgment of the investigator before entering into the study. * Female participants of non-childbearing potential may be enrolled in the study. Non-childbearing potential is defined as pre-menarche, hysterectomy, bilateral-salpingectomy or bilateral ovariectomy. * Female participants of childbearing potential may be enrolled in the study, if the participant: * has practiced adequate contraception for 30 days prior to first vaccination, and * has a negative pregnancy test\* on the day of vaccination, and * has agreed to follow adequate contraception for 30 days before each of the 2 subsequent vaccinations and for 30 days after each vaccination \* Urine samples for pregnancy testing will be collected from female participants of childbearing potential at Visit 1, Visit 3 and Visit 5 prior to the vaccination. Exclusion Criteria: Medical conditions * Current or previous, confirmed or suspected disease caused by N. meningitidis. * Household contact with and/or intimate exposure to an individual with laboratory confirmed N. meningitidis infection within 60 days of enrolment. * Progressive, unstable or uncontrolled clinical conditions. * Clinical conditions representing a contraindication to intramuscular vaccination and blood draws. * Any neuroinflammatory, congenital neurological conditions, encephalopathies, seizures. History of febrile convulsions should not lead to exclusion. * History of any reaction or hypersensitivity likely to be exacerbated by any component of the vaccine(s)/product(s). * Hypersensitivity, including allergy, to any component of vaccines, including diphtheria toxoid (CRM197) and latex medicinal products or medical equipment whose use is foreseen in this study. * Abnormal function or modification of the immune system resulting from: * Autoimmune disorders or immunodeficiency syndromes. * Systemic administration of corticosteroids (PO/IV/IM) for more than 14 consecutive days within 90 days prior to study vaccination. This will mean prednisone equivalent ≥20 mg/day for adult participants / ≥0.5 mg/kg/day with maximum 20 mg/day for paediatric participants. Inhaled and topical steroids are allowed. * Administration of antineoplastic and immunomodulating agents or radiotherapy within 90 days prior to study vaccination. * Administration of long-acting immune-modifying drugs at any time during the study period. * Any other clinical condition that, in the opinion of the investigator, might pose additional risk to the participant due to participation in the study. Prior/Concomitant therapy * Use of any investigational or non-registered product (drug, vaccine or medical device) other than the study vaccine(s)/product(s) during the period starting 30 days before the first dose of study vaccine(s)/product(s) (Day -29 to Day 1), or planned use during the study period. * Previous vaccination with any meningococcal (MenB or MenACWY) vaccine at any time prior to informed consent/ assent (as applicable) with the exception of meningococcal C (conjugated or polysaccharide) vaccination, if the last dose of MenC was received at ≤24 months of age. * Administration of immunoglobulins and/or any blood products or plasma derivatives during the period starting 3 months before the administration of study vaccine/product or planned administration before the next blood sampling visit. * Chronic administration (defined as more than 14 days in total) of immunosuppressants or other immune-modifying drugs during the period starting 90 days prior to the first vaccine/product dose(s). For corticosteroids, this will mean prednisone equivalent ≥20 mg/day for adult participants / ≥0.5 mg/kg/day with maximum of 20 mg/day for paediatric participants. Inhaled and topical steroids are allowed. Prior/Concurrent clinical study experience • Concurrently participating in another clinical study, at any time during the study period, in which the participant has been or will be exposed to an investigational or a non-investigational vaccine/product (drug or medical device). Other exclusions * Child in care. * Pregnant or lactating female. * Female planning to become pregnant / planning to discontinue contraceptive precautions during the windows reported in the inclusion criterion. * History of /current chronic alcohol abuse and/or drug abuse as determined by the investigator. * Any study personnel or immediate dependants, family, or household members.