Study to Assess the Safety, Tolerability and Explore the Immunogenicity of EG-HZ in Healthy Adult Volunteers

Inclusion Criteria: 1. Able to understand and comply with the study procedures, understand the risks involved in the study, and provide written informed consent before the first study-specific procedure; 2. Healthy male and female volunteers aged 50 to 70 years at time of Screening; 3. Subjects must have a BMI between ≥18.0 and ≤35.0 kg/m2 at Screening; 4. Availability to volunteer for the entire study duration and willing to adhere to all protocol requirements; 5. Must have a negative urine pregnancy test on the day of dosing prior to each vaccination; 6. Subjects must have clinical laboratory values within normal ranges as specified by the testing laboratory, unless deemed NCS by the PI; 7. Normal physical findings, vital signs, 12-lead ECG, and no significant medical condition at the time of Screening, as judged by the PI; 8. Must agree to abstain from alcohol intake from 48 hours before each vaccination; 9. Must be non-smokers or, if light or occasional smokers (\<10 cigarettes per day), must agree to abstain from smoking from 48 hours before each vaccination; 10. Must have a negative urine drug screen/alcohol breath test on the day of dosing prior to each vaccination. Repeat urine drug screens will be permitted for suspected false positive results; 11. Must agree to use highly effective, medically accepted double-barrier contraception (both male and female partners) from Screening until study completion as specified below in this criterion. Highly effective double-barrier contraception is defined as use of a condom AND one of the following: 1. Birth control pills (The Pill) 2. Depot or injectable birth control 3. IUD 4. Birth Control Patch (e.g., Ortho Evra) 5. NuvaRing® 6. Implantable contraception (e.g., Implanon) 7. Documented evidence of surgical sterilisation at least 6 months prior to Screening, i.e., tubal ligation or hysterectomy for women or vasectomy for men Exclusion Criteria: 1. Pregnant or lactating at Screening or planning to become pregnant (self or partner) at any time during the study, including the follow-up period; 2. History of severe allergic reaction (e.g., anaphylaxis) to any component of the vaccine; 3. History of herpes zoster (Shingles); 4. Previous vaccination against HZ (either a registered product or an investigational product through participation in a HZ vaccine study); 5. Previous vaccination against VZV; 6. Chronic administration (defined as more than 14 consecutive days) of immunosuppressants or other immune-modifying drugs within 3 months prior to the first vaccine dose (intra-articular, intra-bursal, or topical \[skin or eyes\] corticosteroids are permitted at the discretion of the PI); 7. History of autoimmune disease/s which required therapeutic intervention/s, or any active autoimmune disease requiring therapeutic intervention/s including but not limited to: systemic or cutaneous lupus erythematosus, autoimmune arthritis/rheumatoid arthritis, Guillain-Barré syndrome, multiple sclerosis, Sjögren's syndrome, idiopathic thrombocytopenic purpura, glomerulonephritis, autoimmune thyroiditis, giant cell arteritis (temporal arteritis), psoriasis, and insulin-dependent diabetes mellitus (i.e. type 1 diabetes); 8. Bleeding diathesis or condition associated with prolonged bleeding that would, in the opinion of the Investigator, contraindicate intramuscular injection; 9. Vaccines administered or scheduled in the period from 4 weeks prior to Dose 1 through to 28 days post-vaccination dose 2, excluding licensed non-replicating vaccines (i.e., inactivated and subunit vaccines, including inactivated and subunit influenza vaccines for seasonal or pandemic flu, with or without adjuvant) administered up to 8 days prior to each dose and/or at least 14 days after any dose of study vaccine (to be determined at the discretion of the PI); 10. Receipt of any immunoglobulins or blood/plasma products within 60 days prior to vaccination on Day 1 and until the EOS/ET visit; 11. Positive test for HCV, HBsAg, or HIV antibody at Screening; 12. History or presence of any clinically unstable medical, surgical or psychiatric condition, at the discretion of the Investigator; 13. Active malignancy and/or history of malignancy in the past 5 years, except for completely excised basal cell carcinoma or low grade cervical intraepithelial neoplasia; 14. History of significant hypersensitivity or anaphylaxis involving any drug, food or other precipitating agent (e.g., bee sting); 15. Abnormal laboratory values or investigations (including ECG) that, in the opinion of the Investigator, are deemed clinically significant and would preclude participation in the study; 16. Renal insufficiency defined by eGFR \<90 mL/min (CKD-EPI); 17. Hepatic synthetic insufficiency as defined as a serum albumin of \<35 g/L; or serum bilirubin \>20 μmol/L; 18. Acute disease or acute stage of chronic disease and/or fever at the time of enrolment. Fever is defined as temperature ≥ 37.5°C (99.5°F), regardless of the route. Subjects with a minor illness (such as mild diarrhoea, mild upper respiratory infection) without fever may, be enrolled at the discretion of the Investigator; 19. Regular use of any prescribed or non-prescribed medications, including herbal remedies, which, in the opinion of the Investigator, might adversely affect the safety of the subject or the interpretability of study results. Participants who are taking a stable dose of medication for a controlled medications include, for example, stable doses of antidepressants, cholesterol lowering agents, high blood pressure medication, reflux medication, hormone replacement therapy, NSAIDs, paracetamol, occasional Ventolin, etc.); 20. History of or present alcohol abuse, or excessive intake of alcohol, as judged by the Investigator; 21. Blood donation or significant blood loss within 30 days prior to the first study drug administration and until the EOS/ET visit; 22. Plasma donation within 7 days prior to the first study drug administration and until the EOS/ET visit; 23. Administration of another IP (defined as a compound that has not been approved for marketing) or has participated in any other clinical study that included IP treatment within 3 months prior to administration of IP in this study; 24. Any person who is initially excluded from study participation based on one or more of the time-limited exclusion criteria (e.g., acute illness) may be considered for enrollment once the condition has resolved as long as the subject continues to meet all other entry criteria; 25. Subject taking any non-topical antiviral therapy with activity against herpes viruses, including but not limited to acyclovir, famciclovir, ganciclovir, and valacyclovir 3 days prior to vaccination or 14 days after; 26. Any other reason that, in the opinion of the Investigator, might interfere with the evaluation required by the study; 27. The subject is, in the opinion of the Investigator, unlikely to comply with the clinical study protocol or is unsuitable for any other reason.