A Phase 1/2 Study to Determine Safety and Immunogenicity of Two COVID 19 Vaccines VB10.2129 (RBD Candidate) and VB10.2210 (T Cell Candidate) Previously Vaccinated in Healthy Adult Volunteers

Main inclusion criteria:

• Give informed consent by signing the Informed Consent Form (ICF)

SARS CoV 2 vaccination status for Part 1:

1. VB10.2129 (C1): have received 2 or 3 doses of an approved mRNA SARS CoV 2 vaccine, minimum 4.5 months (20 weeks) prior to Visit 1.
2. VB10.2210 (C2): have received 2 doses (primary vaccination) or 3 (primary and boost) doses of an approved mRNA SARS CoV 2 vaccine, minimum 8 weeks prior to Visit 1.

SARS CoV 2 vaccination status for Part 2:

VB10.2129 (C1) and VB10.2210 (C2) Vaccination status prior to Visit 1 will be decided based on data from Part 1.

• Willing and able to comply with scheduled visits, treatment schedule, laboratory tests, lifestyle restrictions (eg, local law and regulations [county specific lock down rules] regarding COVID-19), and other requirements of the study.
• Healthy, in the clinical judgement of the Investigator, based on medical history, physical examination, 12-lead electrocardiogram (ECG), vital signs (systolic/diastolic blood pressure, pulse rate, body temperature, respiratory rate), and clinical laboratory tests (blood chemistry, haematology, and urine chemistry) at Visit 0 (Screening).
• Women of childbearing potential (WOCBP) must have a negative pregnancy test and must agree to practice a highly effective form
• Agree not to be vaccinated with any other vaccine during the study until 28 days after receiving the last study vaccination
• Negative rtPCR-test for SARS-CoV-2

Main exclusion criteria:

• Have had any acute illness with or without fever, within 72 hours prior to the first vaccination
• Symptoms of upper respiratory infection, fever, persistent cough, shortness of breath, runny nose and breathing difficulties
• Breastfeeding or who plan to breastfeed during the study
• Have a known allergy, hypersensitivity, or intolerance to aminoglycosides
• Had any clinically significant or chronic medical condition or any major surgery within the past 5 years which
• Have any surgery planned during the study
• Had any chronic use of any systemic medications, including immunosuppressant's, oral corticosteroids or other immune-modifying drugs, within the 12 months prior to Screening
• Received any vaccination within the 28 days prior to Screening
• Received any prescription medicines (except hormonal contraception for WOCBP) within 14 days prior to Visit 0 (Screening) or over the counter medicines (except paracetamol and acetaminophen at a dose of (≤2 grams/day)) within 48 hours of Visit 0.
• Have a known history or a positive test of HIV 1 or 2, Hep B, or Hep C
• Have a positive rtPCR test for SARS-CoV-2 within 2 days of Screening
• Documented history of previous infection with SARS-CoV-2 and/or who have the presence of serum Ab indicative of a previous SARS-CoV-2 infection
• Have a history of hypersensitivity or have had a serious reaction to a previous vaccination
• Have any abnormality or permanent body art (eg, tattoo) that, would obstruct the ability to observe local reactions at the injection site.
• Have a condition known to put them at high risk for severe COVID-19, including those with any of the following risk factors: Hypertension, diabetes mellitus, chronic pulmonary disease, asthma, chronic liver disease, known stage 3 or worse chronic kidney disease
• Anticipating the need for immunosuppressive treatment within the next 6 months.

Other inclusion or exclusion criteria may apply.