MenACWY (Menveo) is a GSK vaccine intended for protection against disease caused by meningococcal bacteria groups A, C, W and Y in infants, children and adults, licensed in more than 60 countries.

The purpose of this study is to compare the immunogenicity of the currently licensed MenACWY vaccine with the investigational MenACWY liquid vaccine.

Inclusion Criteria:

1. Subjects who, in the opinion of the investigator, can and will comply with the requirements of the protocol or subjects' parent(s)/Legally Acceptable Respresentative(s) [LAR(s)] who, in the opinion of the investigator, can and will comply, with the requirements of the protocol.

2. Written informed consent obtained from the subject/from the parents(s)/LAR(s) of the subject prior to performance of any study specific procedure.

3. Written informed assent obtained for subjects below legal age of consent, if required by local regulations, at the time of enrolment.

4. A male or female between, and including, ≥18 to ≤40 YoA at the time of the first vaccination.

5. Healthy subjects as established by medical history and clinical examination before entering into the study.

6. 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.

7. 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. (approximately 1 month after vaccination).

Exclusion Criteria:

1. Anaphylaxis following the administration of vaccine

2. Any (clinical) condition that in the judgment of the investigator would make intramuscular injection unsafe and/or represents a contraindication to intramuscular vaccination and blood draws.

3. Any confirmed or suspected immunosuppressive or immunodeficient condition, including HIV infection.

4. Progressive, unstable or uncontrolled clinical conditions.

5. Hypersensitivity, including allergy, to any component of vaccines, medicinal products or medical equipment whose use is foreseen in this study.

6. Hypersensitivity to the active substances or to any of the excipients of the vaccine, including diphtheria toxoid (CRM197), or a life-threatening reaction after previous administration of a vaccine containing similar components.

7. Abnormal function of the immune system resulting from:

   • Clinical conditions.
   • Systemic administration of corticosteroids (Per os [PO]/ Intravenous [IV]/ Intramuscular [IM]) for more than 14 consecutive days within 90 days prior to informed consent, and until the Day 29 blood draw.
   • Administration of antineoplastic and immuno-modulating agents or radiotherapy within 90 days prior to informed consent, and until the Day 29 blood draw.

8. Received immunoglobulins or any blood products within 180 days prior to informed consent.

9. Received an investigational or non-registered medicinal product within 30 days prior to informed consent.

10. Any other clinical condition that, in the opinion of the investigator, might interfere with the results of the study or pose additional risk to the subject due to participation in the study.

11. History of any meningococcal vaccination.

12. Individuals who received any other vaccines within 7 days (for inactivated vaccines) or 14 days (for live vaccines) prior to enrolment in this study or who are planning to receive any vaccine within 28 days from the study vaccines*.

    * In case an emergency mass vaccination for an unforeseen public health threat (e.g.: a pandemic) is organised by the public health authorities, outside the routine immunization program, the time period described above can be reduced if necessary for that vaccine provided it is licensed and used according to its Summary of Product Characteristics (SmPC) or Prescribing Information and according to the local governmental recommendations and provided a written approval of the Sponsor is obtained.

13. Administration of long-acting immune-modifying drugs at any time during the study period (e.g. infliximab).

14. Concurrently participating in another clinical study, at any time during the study period, in which the subject has been or will be exposed to an investigational or a non-investigational vaccine/product. (pharmaceutical product or device).

15. Current or previous, confirmed or suspected disease caused by N. meningitidis.

16. Household contact with and/or intimate exposure to an individual with any laboratory confirmed N. meningitidis infection within 60 days prior to study vaccination.

17. Acute disease and/or fever within 3 days prior to study vaccination. Note: enrolment may be postponed/delayed until such transient circumstances have ended.

    • Fever is defined as body temperature ≥ 38.0°C / 100.4°F. The preferred location for measuring temperature in this study will be the oral cavity.
    • Subjects with a minor illness (such as mild diarrhoea, mild upper respiratory infection) without fever may be enrolled at the discretion of the investigator.

18. Received systemic antibiotic treatment within 3 days prior to study vaccination or blood draw.

19. Study personnel as an immediate family or household member.

20. Pregnant or lactating women.

IPD for this study will be made available via the Clinical Study Data Request site.

IPD will be made available within 6 months of publishing the results of the primary endpoints, key secondary endpoints and safety data of the study

Access is provided after a research proposal is submitted and has received approval from the Independent Review Panel and after a Data Sharing Agreement is in place. Access is provided for an initial period of 12 months but an extension can be granted, when justified, for up to another 12 months.

Data will be collected in an observer-blind manner. By observer-blind, it is meant that during the course of the study, the vaccine recipient and those responsible for the evaluation of any study endpoint (e.g. safety, reactogenicity and immunogenicity) will all be unaware of which vaccine was administered. To do so, vaccine preparation and administration will be done by authorized medical personnel who will not participate in any of the study clinical evaluations.