Current participant exclusion criteria as of 10/01/2022: 1. Receipt of any vaccine (licensed or investigational) other than the study intervention within 30 days before and after each study vaccination (one week for licensed seasonal influenza vaccine or pneumococcal vaccine) 2. Prior or planned receipt of any other investigational or licensed vaccine or product likely to impact on the interpretation of the trial data (e.g. adenovirus vectored vaccines, any coronavirus vaccines) 3. Pregnant at enrolment or planning to become pregnant during the first 3 months of the trial period 4. Administration of immunoglobulins and/or any blood products within the three months preceding the planned administration of the vaccines 5. Any confirmed or suspected immunosuppressive or immunodeficient state, asplenia, recurrent severe infections and use of immunosuppressant medication within the past 6 months, except topical steroids or short-term oral steroids (course lasting =14 days) 6. History of allergic disease or reactions likely to be exacerbated by any component of study vaccines (e.g. hypersensitivity to the active substance or any of the SmPC-listed ingredients of the Pfizer vaccine) 7. Any history of anaphylaxis 8. Current diagnosis of or treatment for cancer, except basal cell carcinoma of the skin and cervical carcinoma in situ 9. Bleeding disorder (e.g. factor deficiency, coagulopathy, or platelet disorder), or prior history of significant bleeding or bruising following IM injections or venepuncture 10. Continuous use of anticoagulants, such as coumarins and related anticoagulants (i.e. warfarin) or novel oral anticoagulants (i.e. apixaban, rivaroxaban, dabigatran, and edoxaban) 11. History of cerebral venous sinus thrombosis, antiphospholipid syndrome, or heparin-induced thrombocytopenia and thrombosis (HITT or HIT type 2) 12. Suspected or known current alcohol or drug dependency 13. Any other significant disease, disorder, or finding which may significantly increase the risk to the volunteer because of participation in the study, affect the ability of the volunteer to participate in the study, or impair interpretation of the study data 14. Severe and/or uncontrolled cardiovascular disease, respiratory disease, gastrointestinal disease, liver disease, renal disease, an endocrine disorder, and neurological illness (mild/moderate well-controlled comorbidities are allowed) 15. History of active or previous auto-immune neurological disorders (e.g. multiple sclerosis, Guillain-Barre syndrome, transverse myelitis). Bell’s palsy will not be an exclusion criterion. 16. Significant renal or hepatic impairment 17. Scheduled elective surgery during the trial 18. Life expectancy of <6 months 19. Have participated in another research trial involving an investigational product in the past 12 weeks. This does not exclude participants in trials of AZD1222 (ChAdOx1 nCOV-19) who were originally recipients of placebo and who received AZD1222 (ChAdOx1 nCOV-19) or BNT162b2 as part of the “national schedule” with AZD1222 (ChAdOx1 nCOV-19) or BNT162b2 dose 1 from mid-Dec 2020 through end February 2021 and then AZD1222 (ChAdOx1 nCOV-19) or BNT162b2

Current participant exclusion criteria as of 10/01/2022: 1. Receipt of any vaccine (licensed or investigational) other than the study intervention within 30 days before and after each study vaccination (one week for licensed seasonal influenza vaccine or pneumococcal vaccine) 2. Prior or planned receipt of any other investigational or licensed vaccine or product likely to impact on the interpretation of the trial data (e.g. adenovirus vectored vaccines, any coronavirus vaccines) 3. Pregnant at enrolment or planning to become pregnant during the first 3 months of the trial period 4. Administration of immunoglobulins and/or any blood products within the three months preceding the planned administration of the vaccines 5. Any confirmed or suspected immunosuppressive or immunodeficient state, asplenia, recurrent severe infections and use of immunosuppressant medication within the past 6 months, except topical steroids or short-term oral steroids (course lasting =14 days) 6. History of allergic disease or reactions likely to be exacerbated by any component of study vaccines (e.g. hypersensitivity to the active substance or any of the SmPC-listed ingredients of the Pfizer vaccine) 7. Any history of anaphylaxis 8. Current diagnosis of or treatment for cancer, except basal cell carcinoma of the skin and cervical carcinoma in situ 9. Bleeding disorder (e.g. factor deficiency, coagulopathy, or platelet disorder), or prior history of significant bleeding or bruising following IM injections or venepuncture 10. Continuous use of anticoagulants, such as coumarins and related anticoagulants (i.e. warfarin) or novel oral anticoagulants (i.e. apixaban, rivaroxaban, dabigatran, and edoxaban) 11. History of cerebral venous sinus thrombosis, antiphospholipid syndrome, or heparin-induced thrombocytopenia and thrombosis (HITT or HIT type 2) 12. Suspected or known current alcohol or drug dependency 13. Any other significant disease, disorder, or finding which may significantly increase the risk to the volunteer because of participation in the study, affect the ability of the volunteer to participate in the study, or impair interpretation of the study data 14. Severe and/or uncontrolled cardiovascular disease, respiratory disease, gastrointestinal disease, liver disease, renal disease, an endocrine disorder, and neurological illness (mild/moderate well-controlled comorbidities are allowed) 15. History of active or previous auto-immune neurological disorders (e.g. multiple sclerosis, Guillain-Barre syndrome, transverse myelitis). Bell’s palsy will not be an exclusion criterion. 16. Significant renal or hepatic impairment 17. Scheduled elective surgery during the trial 18. Life expectancy of <6 months 19. Have participated in another research trial involving an investigational product in the past 12 weeks. This does not exclude participants in trials of AZD1222 (ChAdOx1 nCOV-19) who were originally recipients of placebo and who received AZD1222 (ChAdOx1 nCOV-19) or BNT162b2 as part of the “national schedule” with AZD1222 (ChAdOx1 nCOV-19) or BNT162b2 dose 1 from mid-Dec 2020 through end February 2021 and then AZD1222 (ChAdOx1 nCOV-19) or BNT162b2

Current participant exclusion criteria as of 03/06/2021: 1. Receipt of any vaccine (licensed or investigational) other than the study intervention within 30 days before and after each study vaccination (one week for licensed seasonal influenza vaccine or pneumococcal vaccine) 2. Prior or planned receipt of any other investigational or licensed vaccine or product likely to impact on the interpretation of the trial data (e.g. adenovirus vectored vaccines, any coronavirus vaccines) 3. Pregnant at enrolment or planning to become pregnant during the first 3 months of the trial period 4. Administration of immunoglobulins and/or any blood products within the three months preceding the planned administration of the vaccines 5. Any confirmed or suspected immunosuppressive or immunodeficient state, asplenia, recurrent severe infections and use of immunosuppressant medication within the past 6 months, except topical steroids or short-term oral steroids (course lasting =14 days) 6. History of allergic disease or reactions likely to be exacerbated by any component of study vaccines (e.g. hypersensitivity to the active substance or any of the SmPC-listed ingredients of the Pfizer vaccine) 7. Any history of anaphylaxis 8. Current diagnosis of or treatment for cancer, except basal cell carcinoma of the skin and cervical carcinoma in situ 9. Bleeding disorder (e.g. factor deficiency, coagulopathy, or platelet disorder), or prior history of significant bleeding or bruising following IM injections or venepuncture 10. Continuous use of anticoagulants, such as coumarins and related anticoagulants (i.e. warfarin) or novel oral anticoagulants (i.e. apixaban, rivaroxaban, dabigatran, and edoxaban) 11. History of cerebral venous sinus thrombosis, antiphospholipid syndrome, or heparin-induced thrombocytopenia and thrombosis (HITT or HIT type 2) 12. Suspected or known current alcohol or drug dependency 13. Any other significant disease, disorder, or finding which may significantly increase the risk to the volunteer because of participation in the study, affect the ability of the volunteer to participate in the study, or impair interpretation of the study data 14. Severe and/or uncontrolled cardiovascular disease, respiratory disease, gastrointestinal disease, liver disease, renal disease, an endocrine disorder, and neurological illness (mild/moderate well-controlled comorbidities are allowed) 15. History of active or previous auto-immune neurological disorders (e.g. multiple sclerosis, Guillain-Barre syndrome, transverse myelitis). Bell’s palsy will not be an exclusion criterion. 16.Significant renal or hepatic impairment 17. Scheduled elective surgery during the trial 18. Life expectancy of <6 months 19. Have participated in another research trial involving an investigational product in the past 12 weeks 20. Insufficient level of English language to undertake all study requirements in the opinion of the Investigators except where translation has been able to be provided and is available Previous participant exclusion criteria: 1. Receipt of any vaccine (licensed or investigational) other than the s

Current participant exclusion criteria as of 03/06/2021: 1. Receipt of any vaccine (licensed or investigational) other than the study intervention within 30 days before and after each study vaccination (one week for licensed seasonal influenza vaccine or pneumococcal vaccine) 2. Prior or planned receipt of any other investigational or licensed vaccine or product likely to impact on the interpretation of the trial data (e.g. adenovirus vectored vaccines, any coronavirus vaccines) 3. Pregnant at enrolment or planning to become pregnant during the first 3 months of the trial period 4. Administration of immunoglobulins and/or any blood products within the three months preceding the planned administration of the vaccines 5. Any confirmed or suspected immunosuppressive or immunodeficient state, asplenia, recurrent severe infections and use of immunosuppressant medication within the past 6 months, except topical steroids or short-term oral steroids (course lasting =14 days) 6. History of allergic disease or reactions likely to be exacerbated by any component of study vaccines (e.g. hypersensitivity to the active substance or any of the SmPC-listed ingredients of the Pfizer vaccine) 7. Any history of anaphylaxis 8. Current diagnosis of or treatment for cancer, except basal cell carcinoma of the skin and cervical carcinoma in situ 9. Bleeding disorder (e.g. factor deficiency, coagulopathy, or platelet disorder), or prior history of significant bleeding or bruising following IM injections or venepuncture 10. Continuous use of anticoagulants, such as coumarins and related anticoagulants (i.e. warfarin) or novel oral anticoagulants (i.e. apixaban, rivaroxaban, dabigatran, and edoxaban) 11. History of cerebral venous sinus thrombosis, antiphospholipid syndrome, or heparin-induced thrombocytopenia and thrombosis (HITT or HIT type 2) 12. Suspected or known current alcohol or drug dependency 13. Any other significant disease, disorder, or finding which may significantly increase the risk to the volunteer because of participation in the study, affect the ability of the volunteer to participate in the study, or impair interpretation of the study data 14. Severe and/or uncontrolled cardiovascular disease, respiratory disease, gastrointestinal disease, liver disease, renal disease, an endocrine disorder, and neurological illness (mild/moderate well-controlled comorbidities are allowed) 15. History of active or previous auto-immune neurological disorders (e.g. multiple sclerosis, Guillain-Barre syndrome, transverse myelitis). Bell’s palsy will not be an exclusion criterion. 16.Significant renal or hepatic impairment 17. Scheduled elective surgery during the trial 18. Life expectancy of <6 months 19. Have participated in another research trial involving an investigational product in the past 12 weeks 20. Insufficient level of English language to undertake all study requirements in the opinion of the Investigators except where translation has been able to be provided and is available Previous participant exclusion criteria: 1. Receipt of any vaccine (licensed or investigational) other than the s

1. Receipt of any vaccine (licensed or investigational) other than the study intervention within 30 days before and after each study vaccination (one week for licensed seasonal influenza vaccine or pneumococcal vaccine) 2. Prior or planned receipt of any other investigational or licensed vaccine or product likely to impact on the interpretation of the trial data (e.g. adenovirus vectored vaccines, any coronavirus vaccines) 3. Pregnant at enrolment or planning to become pregnant during the trial period 4. Administration of immunoglobulins and/or any blood products within the three months preceding the planned administration of the vaccines 5. Any confirmed or suspected immunosuppressive or immunodeficient state, asplenia, recurrent severe infections and use of immunosuppressant medication within the past 6 months, except topical steroids or short-term oral steroids (course lasting =14 days) 6. History of allergic disease or reactions likely to be exacerbated by any component of study vaccines (e.g. hypersensitivity to the active substance or any of the SmPC-listed ingredients of the Pfizer vaccine) 7. Any history of anaphylaxis 8. Current diagnosis of or treatment for cancer, except basal cell carcinoma of the skin and cervical carcinoma in situ 9. Bleeding disorder (e.g. factor deficiency, coagulopathy, or platelet disorder), or prior history of significant bleeding or bruising following IM injections or venepuncture 10. Continuous use of anticoagulants, such as coumarins and related anticoagulants (i.e. warfarin) or novel oral anticoagulants (i.e. apixaban, rivaroxaban, dabigatran, and edoxaban) 11. History of cerebral venous sinus thrombosis, antiphospholipid syndrome, or heparin-induced thrombocytopenia and thrombosis (HITT or HIT type 2) 12. Suspected or known current alcohol or drug dependency 13. Any other significant disease, disorder, or finding which may significantly increase the risk to the volunteer because of participation in the study, affect the ability of the volunteer to participate in the study, or impair interpretation of the study data 14. Severe and/or uncontrolled cardiovascular disease, respiratory disease, gastrointestinal disease, liver disease, renal disease, an endocrine disorder, and neurological illness (mild/moderate well-controlled comorbidities are allowed) 15. History of active or previous auto-immune neurological disorders (e.g. multiple sclerosis, Guillain-Barre syndrome, transverse myelitis). Bell’s palsy will not be an exclusion criterion. 16. History of laboratory-confirmed COVID-19 prior to enrolment (history of SARS-CoV-2 detection by PCR, or positive antibody test to SARS-CoV-2 prior to having received COVID-19 vaccination) 17. Significant renal or hepatic impairment 18. Scheduled elective surgery during the trial 19. Life expectancy of <6 months 20. Have participated in another research trial involving an investigational product in the past 12 weeks 21. Insufficient level of English language to undertake all study requirements in the opinion of the Investigators except where translation has been able to be provided and is available

1. Receipt of any vaccine (licensed or investigational) other than the study intervention within 30 days before and after each study vaccination (one week for licensed seasonal influenza vaccine or pneumococcal vaccine) 2. Prior or planned receipt of any other investigational or licensed vaccine or product likely to impact on the interpretation of the trial data (e.g. adenovirus vectored vaccines, any coronavirus vaccines) 3. Pregnant at enrolment or planning to become pregnant during the trial period 4. Administration of immunoglobulins and/or any blood products within the three months preceding the planned administration of the vaccines 5. Any confirmed or suspected immunosuppressive or immunodeficient state, asplenia, recurrent severe infections and use of immunosuppressant medication within the past 6 months, except topical steroids or short-term oral steroids (course lasting =14 days) 6. History of allergic disease or reactions likely to be exacerbated by any component of study vaccines (e.g. hypersensitivity to the active substance or any of the SmPC-listed ingredients of the Pfizer vaccine) 7. Any history of anaphylaxis 8. Current diagnosis of or treatment for cancer, except basal cell carcinoma of the skin and cervical carcinoma in situ 9. Bleeding disorder (e.g. factor deficiency, coagulopathy, or platelet disorder), or prior history of significant bleeding or bruising following IM injections or venepuncture 10. Continuous use of anticoagulants, such as coumarins and related anticoagulants (i.e. warfarin) or novel oral anticoagulants (i.e. apixaban, rivaroxaban, dabigatran, and edoxaban) 11. History of cerebral venous sinus thrombosis, antiphospholipid syndrome, or heparin-induced thrombocytopenia and thrombosis (HITT or HIT type 2) 12. Suspected or known current alcohol or drug dependency 13. Any other significant disease, disorder, or finding which may significantly increase the risk to the volunteer because of participation in the study, affect the ability of the volunteer to participate in the study, or impair interpretation of the study data 14. Severe and/or uncontrolled cardiovascular disease, respiratory disease, gastrointestinal disease, liver disease, renal disease, an endocrine disorder, and neurological illness (mild/moderate well-controlled comorbidities are allowed) 15. History of active or previous auto-immune neurological disorders (e.g. multiple sclerosis, Guillain-Barre syndrome, transverse myelitis). Bell’s palsy will not be an exclusion criterion. 16. History of laboratory-confirmed COVID-19 prior to enrolment (history of SARS-CoV-2 detection by PCR, or positive antibody test to SARS-CoV-2 prior to having received COVID-19 vaccination) 17. Significant renal or hepatic impairment 18. Scheduled elective surgery during the trial 19. Life expectancy of <6 months 20. Have participated in another research trial involving an investigational product in the past 12 weeks 21. Insufficient level of English language to undertake all study requirements in the opinion of the Investigators except where translation has been able to be provided and is available