1. Previous clinical or microbiological confirmed diagnosis of COVID-19. 2. Febrile illness within 72hours before first vaccination (this is a temporary exclusion criterion). 3. Unstable, severe, progressive disease in the past 3 months. 4. History of malignancy during the past 5 years. 5. History of severe adverse reaction associated and/or anaphylaxis with a vaccine. 6. Known allergic reactions of any severity to polyethylene glycol [PEG] or to polysorbate (due to potential cross-reactive hypersensitivity with the vaccine ingredient PEG). 7. Primary or secondary immunodeficiency disorders (e.g. immunosuppressive disease or therapy, human immunodeficiency virus (HIV) infection…). 8. Chronic administration (defined as more than 14 days in total) of immunosuppressant or other immune-modifying drugs during the period starting 6 months prior to the first vaccine dose. For corticosteroids, this will mean prednisone 20 mg/day, or equivalent. Inhaled, nasal, opthalmic and topical steroids are allowed. 9. Pregnancy or lactation. 10. History of drug or alcohol abuse. 11. Anything in the opinion of the investigator that would prevent volunteers from completing the study or put the volunteer at risk, including relevant psychiatric diagnosis. 12. Previous vaccination or planned to accept other vaccination during this study with any coronavirus vaccine outside this study. 13. Previous vaccination or planned to accept other vaccination during this study with any coronavirus vaccine outside this study, with the exception of a third COVID-19 vaccine during fall/winter ’21-‘22. 14. Receipt of blood/plasma products or immunoglobulin, from 60 days before study intervention administration or planned receipt throughout the study. 15. Participation in another clinical trial with an IMP or a new medical device within 28 days prior to study entry and/or during study participation. 16. Participant is an employee of the investigator or study site, with direct involvement in the proposed study or other studies under the direction of that investigator or study site, as well as first degree family members and household members of the employees or the investigator, or an employee of the sponsor.

1. Previous clinical or microbiological confirmed diagnosis of COVID-19. 2. Febrile illness within 72hours before first vaccination (this is a temporary exclusion criterion). 3. Unstable, severe, progressive disease in the past 3 months. 4. History of malignancy during the past 5 years. 5. History of severe adverse reaction associated and/or anaphylaxis with a vaccine. 6. Known allergic reactions of any severity to polyethylene glycol [PEG] or to polysorbate (due to potential cross-reactive hypersensitivity with the vaccine ingredient PEG). 7. Primary or secondary immunodeficiency disorders (e.g. immunosuppressive disease or therapy, human immunodeficiency virus (HIV) infection…). 8. Chronic administration (defined as more than 14 days in total) of immunosuppressant or other immune-modifying drugs during the period starting 6 months prior to the first vaccine dose. For corticosteroids, this will mean prednisone 20 mg/day, or equivalent. Inhaled, nasal, opthalmic and topical steroids are allowed. 9. Pregnancy or lactation. 10. History of drug or alcohol abuse. 11. Anything in the opinion of the investigator that would prevent volunteers from completing the study or put the volunteer at risk, including relevant psychiatric diagnosis. 12. Previous vaccination or planned to accept other vaccination during this study with any coronavirus vaccine outside this study. 13. Previous vaccination or planned to accept other vaccination during this study with any coronavirus vaccine outside this study, with the exception of a third COVID-19 vaccine during fall/winter ’21-‘22. 14. Receipt of blood/plasma products or immunoglobulin, from 60 days before study intervention administration or planned receipt throughout the study. 15. Participation in another clinical trial with an IMP or a new medical device within 28 days prior to study entry and/or during study participation. 16. Participant is an employee of the investigator or study site, with direct involvement in the proposed study or other studies under the direction of that investigator or study site, as well as first degree family members and household members of the employees or the investigator, or an employee of the sponsor.

1. Previous clinical or microbiological confirmed diagnosis of COVID-19. 2. Febrile illness within 72hours before first vaccination (this is a temporary exclusion criterion). 3. Unstable, severe, progressive disease in the past 3 months. 4. History of malignancy during the past 5 years. 5. History of severe adverse reaction associated with a vaccine and/or anaphylaxis. 6. Known allergic reactions of any severity to polyethylene glycol [PEG] or to polysorbate (due to potential cross-reactive hypersensitivity with the vaccine ingredient PEG). 7. Primary or secondary immunodeficiency disorders (e.g. immunosuppressive disease or therapy, human immunodeficiency virus (HIV) infection…). 8. Chronic administration (defined as more than 14 days in total) of immunosuppressant or other immune-modifying drugs during the period starting 6 months prior to the first vaccine dose. For corticosteroids, this will mean prednisone 20 mg/day, or equivalent. Inhaled, nasal, opthalmic and topical steroids are allowed. 9. Pregnancy or lactation. 10. History of drug or alcohol abuse. 11. Anything in the opinion of the investigator that would prevent volunteers from completing the study or put the volunteer at risk, including relevant psychiatric diagnosis. 12. Previous vaccination or planned to accept other vaccination during this study with any coronavirus vaccine outside this study. 13. Vaccination with any licensed vaccine, 14 days before or planned within 14days after each study vaccination (28 days for live attenuated vaccines). 14. Receipt of blood/plasma products or immunoglobulin, from 60 days before study intervention administration or planned receipt throughout the study. 15. Participation in another clinical trial with an IMP or a new medical device within 28 days prior to study entry and/or during study participation. 16. Participant is an employee of the investigator or study site, with direct involvement in the proposed study or other studies under the direction of that investigator or study site, as well as first degree family members and household members of the employees or the investigator, or an employee of the sponsor.

1. Previous clinical or microbiological confirmed diagnosis of COVID-19. 2. Febrile illness within 72hours before first vaccination (this is a temporary exclusion criterion). 3. Unstable, severe, progressive disease in the past 3 months. 4. History of malignancy during the past 5 years. 5. History of severe adverse reaction associated with a vaccine and/or anaphylaxis. 6. Known allergic reactions of any severity to polyethylene glycol [PEG] or to polysorbate (due to potential cross-reactive hypersensitivity with the vaccine ingredient PEG). 7. Primary or secondary immunodeficiency disorders (e.g. immunosuppressive disease or therapy, human immunodeficiency virus (HIV) infection…). 8. Chronic administration (defined as more than 14 days in total) of immunosuppressant or other immune-modifying drugs during the period starting 6 months prior to the first vaccine dose. For corticosteroids, this will mean prednisone 20 mg/day, or equivalent. Inhaled, nasal, opthalmic and topical steroids are allowed. 9. Pregnancy or lactation. 10. History of drug or alcohol abuse. 11. Anything in the opinion of the investigator that would prevent volunteers from completing the study or put the volunteer at risk, including relevant psychiatric diagnosis. 12. Previous vaccination or planned to accept other vaccination during this study with any coronavirus vaccine outside this study. 13. Vaccination with any licensed vaccine, 14 days before or planned within 14days after each study vaccination (28 days for live attenuated vaccines). 14. Receipt of blood/plasma products or immunoglobulin, from 60 days before study intervention administration or planned receipt throughout the study. 15. Participation in another clinical trial with an IMP or a new medical device within 28 days prior to study entry and/or during study participation. 16. Participant is an employee of the investigator or study site, with direct involvement in the proposed study or other studies under the direction of that investigator or study site, as well as first degree family members and household members of the employees or the investigator, or an employee of the sponsor.