participants with fever > 37.5°c (irrespective of method), or any acute illness at baseline (day 1) or within 3 days prior to randomization. participants meeting this criterion may be rescheduled (within the relevant window). febrile participants with minor illnesses can be enrolled at the discretion of the investigator. participants with confirmed sars-cov-2 infection (as defined by rapid covid antigen test or an equivalent at visit 1) or with history of covid-19. participants who have received a prior investigational or licensed covid-19 vaccine, or previous hepatitis a vaccine 12 months prior to day 1. any confirmed or suspected immunosuppressive or immunodeficient condition resulting from disease (e.g., malignancy, hiv infection) or having received systemic corticosteroids and/or immunosuppressive/cytotoxic therapy (e.g., medications used for cancer chemotherapy, organ transplantation or to treat autoimmune disorders other than ra, ibd or rrms) within 6 months prior to enrollment. participants with any progressive unstable or uncontrolled clinical conditions. participants with surgery scheduled during the study period. participants who have a history of severe adverse reaction associated with a vaccine or severe allergic reaction (e.g., anaphylaxis) to any component of the study vaccines, such as hepatitis a vaccine (as outlined in the havrix summary of product characteristics, eu smpc, gsk, 2020), or cpg 1018/alum/scb-2019 components as outlined in the latest ib. participants who have a history of malignancy within 1 year before screening (exceptions are squamous and basal cell carcinomas of the skin and carcinoma in situ of the cervix which have been cured, or other malignancies with minimal risk of recurrence). participants who have received any other investigational product within 3 months to day 1 or intent to participate in another clinical study at any time during the conduct of this study. participants who have received any other licensed vaccines within 14 days prior to enrollment in this study or who are planning to receive any vaccine up to 14 days after the second vaccination. participants with known bleeding disorder that would, in the opinion of the investigator, contraindicate intramuscular injection. participants who have received treatment with rituximab or any other anti-cd20 monoclonal antibodies within 9 months prior to enrollment or planned during the study period. administration of intravenous immunoglobulins and/or any blood products within 3 months prior to enrollment or planned administration during the study period. participants with any condition that, in the opinion of the investigator, would interfere with the primary study objectives or pose additional participant risk. participants with any seizure disorder, or history of guillian-barré syndrome.

participants with fever > 37.5°c (irrespective of method), or any acute illness at baseline (day 1) or within 3 days prior to randomization. participants meeting this criterion may be rescheduled (within the relevant window). febrile participants with minor illnesses can be enrolled at the discretion of the investigator. participants with confirmed sars-cov-2 infection (as defined by rapid covid antigen test or an equivalent at visit 1) or with history of covid-19. participants who have received a prior investigational or licensed covid-19 vaccine, or previous hepatitis a vaccine 12 months prior to day 1. any confirmed or suspected immunosuppressive or immunodeficient condition resulting from disease (e.g., malignancy, hiv infection) or having received systemic corticosteroids and/or immunosuppressive/cytotoxic therapy (e.g., medications used for cancer chemotherapy, organ transplantation or to treat autoimmune disorders other than ra, ibd or rrms) within 6 months prior to enrollment. participants with any progressive unstable or uncontrolled clinical conditions. participants with surgery scheduled during the study period. participants who have a history of severe adverse reaction associated with a vaccine or severe allergic reaction (e.g., anaphylaxis) to any component of the study vaccines, such as hepatitis a vaccine (as outlined in the havrix summary of product characteristics, eu smpc, gsk, 2020), or cpg 1018/alum/scb-2019 components as outlined in the latest ib. participants who have a history of malignancy within 1 year before screening (exceptions are squamous and basal cell carcinomas of the skin and carcinoma in situ of the cervix which have been cured, or other malignancies with minimal risk of recurrence). participants who have received any other investigational product within 3 months to day 1 or intent to participate in another clinical study at any time during the conduct of this study. participants who have received any other licensed vaccines within 14 days prior to enrollment in this study or who are planning to receive any vaccine up to 14 days after the second vaccination. participants with known bleeding disorder that would, in the opinion of the investigator, contraindicate intramuscular injection. participants who have received treatment with rituximab or any other anti-cd20 monoclonal antibodies within 9 months prior to enrollment or planned during the study period. administration of intravenous immunoglobulins and/or any blood products within 3 months prior to enrollment or planned administration during the study period. participants with any condition that, in the opinion of the investigator, would interfere with the primary study objectives or pose additional participant risk. participants with any seizure disorder, or history of guillian-barré syndrome.

1. participants with fever > 37.5°c (irrespective of method), or any acute illness at baseline (day 1) or within 3 days prior to randomization. participants meeting this criterion may be rescheduled (within the relevant window). febrile participants with minor illnesses can be enrolled at the discretion of the investigator. 2. participants with confirmed sars-cov-2 infection (as defined by rapid covid antigen test or an equivalent at visit 1) or with history of covid-19. 3. participants who have received a prior investigational or licensed covid-19 vaccine, or previous hepatitis a vaccine 12 months prior to day 1. 4. any confirmed or suspected immunosuppressive or immunodeficient condition resulting from disease (e.g., malignancy, hiv infection) or having received systemic corticosteroids and/or immunosuppressive/cytotoxic therapy (e.g., medications used for cancer chemotherapy, organ transplantation or to treat autoimmune disorders other than ra, ibd or rrms) within 6 months prior to enrollment. 5. participants with any progressive unstable or uncontrolled clinical conditions. 6. participants with surgery scheduled during the study period. 7. participants who have a history of severe adverse reaction associated with a vaccine or severe allergic reaction (e.g., anaphylaxis) to any component of the study vaccines, such as hepatitis a vaccine (as outlined in the havrix summary of product characteristics, eu smpc, gsk, 2020), or cpg 1018/alum/scb-2019 components as outlined in the latest ib. 8. participants who have a history of malignancy within 1 year before screening (exceptions are squamous and basal cell carcinomas of the skin and carcinoma in situ of the cervix which have been cured, or other malignancies with minimal risk of recurrence). 9. participants who have received any other investigational product within 3 months to day 1 or intent to participate in another clinical study at any time during the conduct of this study. 10. participants who have received any other licensed vaccines within 14 days prior to enrollment in this study or who are planning to receive any vaccine up to 14 days after the second vaccination. 11. participants with known bleeding disorder that would, in the opinion of the investigator, contraindicate intramuscular injection. 12. participants who have received treatment with rituximab or any other anti-cd20 monoclonal antibodies within 9 months prior to enrollment or planned during the study period. 13. administration of intravenous immunoglobulins and/or any blood products within 3 months prior to enrollment or planned administration during the study period. 14. participants with any condition that, in the opinion of the investigator, would interfere with the primary study objectives or pose additional participant risk. 15. participants with any seizure disorder, or history of guillian-barré syndrome.

1. participants with fever > 37.5°c (irrespective of method), or any acute illness at baseline (day 1) or within 3 days prior to randomization. participants meeting this criterion may be rescheduled (within the relevant window). febrile participants with minor illnesses can be enrolled at the discretion of the investigator. 2. participants with confirmed sars-cov-2 infection (as defined by rapid covid antigen test or an equivalent at visit 1) or with history of covid-19. 3. participants who have received a prior investigational or licensed covid-19 vaccine, or previous hepatitis a vaccine 12 months prior to day 1. 4. any confirmed or suspected immunosuppressive or immunodeficient condition resulting from disease (e.g., malignancy, hiv infection) or having received systemic corticosteroids and/or immunosuppressive/cytotoxic therapy (e.g., medications used for cancer chemotherapy, organ transplantation or to treat autoimmune disorders other than ra, ibd or rrms) within 6 months prior to enrollment. 5. participants with any progressive unstable or uncontrolled clinical conditions. 6. participants with surgery scheduled during the study period. 7. participants who have a history of severe adverse reaction associated with a vaccine or severe allergic reaction (e.g., anaphylaxis) to any component of the study vaccines, such as hepatitis a vaccine (as outlined in the havrix summary of product characteristics, eu smpc, gsk, 2020), or cpg 1018/alum/scb-2019 components as outlined in the latest ib. 8. participants who have a history of malignancy within 1 year before screening (exceptions are squamous and basal cell carcinomas of the skin and carcinoma in situ of the cervix which have been cured, or other malignancies with minimal risk of recurrence). 9. participants who have received any other investigational product within 3 months to day 1 or intent to participate in another clinical study at any time during the conduct of this study. 10. participants who have received any other licensed vaccines within 14 days prior to enrollment in this study or who are planning to receive any vaccine up to 14 days after the second vaccination. 11. participants with known bleeding disorder that would, in the opinion of the investigator, contraindicate intramuscular injection. 12. participants who have received treatment with rituximab or any other anti-cd20 monoclonal antibodies within 9 months prior to enrollment or planned during the study period. 13. administration of intravenous immunoglobulins and/or any blood products within 3 months prior to enrollment or planned administration during the study period. 14. participants with any condition that, in the opinion of the investigator, would interfere with the primary study objectives or pose additional participant risk. 15. participants with any seizure disorder, or history of guillian-barré syndrome.