* presence of any febrile illness or any known or suspected acute illness on the day of immunization. * any condition, which in the opinion of the investigator may make the participant inappropriate for the study. * clinically significant bleeding disorder (e.g., clotting factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following intramuscular injections or venipuncture. * receiving systemic immunomodulatory therapy or history of receiving chemotherapy in the last 5 years other than topical agents. * receipt of systemic glucocorticoids (a dose ≥20 mg/day prednisone or equivalent for 14 days) within 1 month, or any other cytotoxic or immunosuppressive drug within 6 months prior to injection of study vaccine. * cancer diagnosis in the last 5 years, excluding basal cell and squamous cell carcinoma of the skin, which are allowed. * presence of autoimmune disease. * receipt of any investigational drug within 6 months. * receipt of any non-covid-19 authorized vaccines, for example influenza, within 2 weeks of receiving study dose injection. * receipt of any other experimental sars-cov-2/covid-19 or other experimental coronavirus vaccine(s) at any time prior to or during the study. exception: receipt of sars cov 2/covid-19 vaccines at least 4 months prior to day 0 that were experimental at the time of their administration but are currently authorized will not lead to exclusion. * receipt of blood products or immunoglobulin (ivig or imig) within 3 months of study entry/baseline serologic evaluation. * current anti-tuberculosis therapy. * history of any reaction or hypersensitivity likely to be exacerbated by any component of the study vaccine. * hematologic or biochemical laboratory abnormalities (blood or urine), as defined by lab normal ranges. to exclude transient abnormalities, the investigator may repeat a test once, and if the repeat test is normal according to local reference ranges, participant may be enrolled. abnormalities of laboratory values will not be exclusionary if considered not clinically significant by the investigator. * previous (within 4 months prior to day 0) sars-cov-2 infection, based on a documented positive polymerase chain reaction (pcr) test or rapid antigen test, or reported by participant or prior medical history. * member of the study personnel, or immediate family member or household member of the study personnel.

* presence of any febrile illness or any known or suspected acute illness on the day of immunization. * any condition, which in the opinion of the investigator may make the participant inappropriate for the study. * clinically significant bleeding disorder (e.g., clotting factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following intramuscular injections or venipuncture. * receiving systemic immunomodulatory therapy or history of receiving chemotherapy in the last 5 years other than topical agents. * receipt of systemic glucocorticoids (a dose ≥20 mg/day prednisone or equivalent for 14 days) within 1 month, or any other cytotoxic or immunosuppressive drug within 6 months prior to injection of study vaccine. * cancer diagnosis in the last 5 years, excluding basal cell and squamous cell carcinoma of the skin, which are allowed. * presence of autoimmune disease. * receipt of any investigational drug within 6 months. * receipt of any non-covid-19 authorized vaccines, for example influenza, within 2 weeks of receiving study dose injection. * receipt of any other experimental sars-cov-2/covid-19 or other experimental coronavirus vaccine(s) at any time prior to or during the study. exception: receipt of sars cov 2/covid-19 vaccines at least 4 months prior to day 0 that were experimental at the time of their administration but are currently authorized will not lead to exclusion. * receipt of blood products or immunoglobulin (ivig or imig) within 3 months of study entry/baseline serologic evaluation. * current anti-tuberculosis therapy. * history of any reaction or hypersensitivity likely to be exacerbated by any component of the study vaccine. * hematologic or biochemical laboratory abnormalities (blood or urine), as defined by lab normal ranges. to exclude transient abnormalities, the investigator may repeat a test once, and if the repeat test is normal according to local reference ranges, participant may be enrolled. abnormalities of laboratory values will not be exclusionary if considered not clinically significant by the investigator. * previous (within 4 months prior to day 0) sars-cov-2 infection, based on a documented positive polymerase chain reaction (pcr) test or rapid antigen test, or reported by participant or prior medical history. * member of the study personnel, or immediate family member or household member of the study personnel.

presence of any febrile illness or any known or suspected acute illness on the day of immunization. any condition, which in the opinion of the investigator may make the participant inappropriate for the study. clinically significant bleeding disorder (e.g., clotting factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following intramuscular injections or venipuncture. receiving systemic immunomodulatory therapy or history of receiving chemotherapy in the last 5 years other than topical agents. receipt of systemic glucocorticoids (a dose ≥20 mg/day prednisone or equivalent for 14 days) within 1 month, or any other cytotoxic or immunosuppressive drug within 6 months prior to injection of study vaccine. cancer diagnosis in the last 5 years, excluding basal cell and squamous cell carcinoma of the skin, which are allowed. presence of autoimmune disease. receipt of any investigational drug within 6 months. receipt of any non-covid-19 authorized vaccines, for example influenza, within 2 weeks of receiving study dose injection. receipt of any other experimental sars-cov-2/covid-19 or other experimental coronavirus vaccine(s) at any time prior to or during the study. exception: receipt of sars cov 2/covid-19 vaccines at least 4 months prior to day 0 that were experimental at the time of their administration but are currently authorized will not lead to exclusion. receipt of blood products or immunoglobulin (ivig or imig) within 3 months of study entry/baseline serologic evaluation. current anti-tuberculosis therapy. history of any reaction or hypersensitivity likely to be exacerbated by any component of the study vaccine. hematologic or biochemical laboratory abnormalities (blood or urine), as defined by lab normal ranges. to exclude transient abnormalities, the investigator may repeat a test once, and if the repeat test is normal according to local reference ranges, participant may be enrolled. abnormalities of laboratory values will not be exclusionary if considered not clinically significant by the investigator. previous (within 4 months prior to day 0) sars-cov-2 infection, based on a documented positive polymerase chain reaction (pcr) test or rapid antigen test, or reported by participant or prior medical history. member of the study personnel, or immediate family member or household member of the study personnel.

presence of any febrile illness or any known or suspected acute illness on the day of immunization. any condition, which in the opinion of the investigator may make the participant inappropriate for the study. clinically significant bleeding disorder (e.g., clotting factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following intramuscular injections or venipuncture. receiving systemic immunomodulatory therapy or history of receiving chemotherapy in the last 5 years other than topical agents. receipt of systemic glucocorticoids (a dose ≥20 mg/day prednisone or equivalent for 14 days) within 1 month, or any other cytotoxic or immunosuppressive drug within 6 months prior to injection of study vaccine. cancer diagnosis in the last 5 years, excluding basal cell and squamous cell carcinoma of the skin, which are allowed. presence of autoimmune disease. receipt of any investigational drug within 6 months. receipt of any non-covid-19 authorized vaccines, for example influenza, within 2 weeks of receiving study dose injection. receipt of any other experimental sars-cov-2/covid-19 or other experimental coronavirus vaccine(s) at any time prior to or during the study. exception: receipt of sars cov 2/covid-19 vaccines at least 4 months prior to day 0 that were experimental at the time of their administration but are currently authorized will not lead to exclusion. receipt of blood products or immunoglobulin (ivig or imig) within 3 months of study entry/baseline serologic evaluation. current anti-tuberculosis therapy. history of any reaction or hypersensitivity likely to be exacerbated by any component of the study vaccine. hematologic or biochemical laboratory abnormalities (blood or urine), as defined by lab normal ranges. to exclude transient abnormalities, the investigator may repeat a test once, and if the repeat test is normal according to local reference ranges, participant may be enrolled. abnormalities of laboratory values will not be exclusionary if considered not clinically significant by the investigator. previous (within 4 months prior to day 0) sars-cov-2 infection, based on a documented positive polymerase chain reaction (pcr) test or rapid antigen test, or reported by participant or prior medical history. member of the study personnel, or immediate family member or household member of the study personnel.

presence of any febrile illness or any known or suspected acute illness on the day of immunization. any condition, which in the opinion of the investigator may make the participant inappropriate for the study. clinically significant bleeding disorder (e.g., clotting factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following intramuscular injections or venipuncture. receiving systemic immunomodulatory therapy or history of receiving chemotherapy in the last 5 years other than topical agents. receipt of systemic glucocorticoids (a dose ≥20 mg/day prednisone or equivalent for 14 days) within 1 month, or any other cytotoxic or immunosuppressive drug within 6 months prior to injection of study vaccine. cancer diagnosis in the last 5 years, excluding basal cell and squamous cell carcinoma of the skin, which are allowed. presence of autoimmune disease. receipt of any investigational drug within 6 months. receipt of any non-covid-19 authorized vaccines, for example influenza, within 2 weeks of receiving study dose injection. receipt of any other experimental sars-cov-2/covid-19 or other experimental coronavirus vaccine(s) at any time prior to or during the study. exception: receipt of sars cov 2/covid-19 vaccines at least 6 months prior to day 0 that were experimental at the time of their administration but are currently authorized will not lead to exclusion. receipt of blood products or immunoglobulin (ivig or imig) within 3 months of study entry/baseline serologic evaluation. current anti-tuberculosis therapy. history of any reaction or hypersensitivity likely to be exacerbated by any component of the study vaccine. hematologic or biochemical laboratory abnormalities (blood or urine), as defined by lab normal ranges. to exclude transient abnormalities, the investigator may repeat a test once, and if the repeat test is normal according to local reference ranges, participant may be enrolled. abnormalities of laboratory values will not be exclusionary if considered not clinically significant by the investigator. previous (within 6 months prior to day 0) sars-cov-2 infection, based on a documented positive polymerase chain reaction (pcr) test or rapid antigen test, or reported by participant or prior medical history reports (not applicable for subjects in exploratory phase 2 study arm). member of the study personnel, or immediate family member or household member of the study personnel.

presence of any febrile illness or any known or suspected acute illness on the day of immunization. any condition, which in the opinion of the investigator may make the participant inappropriate for the study. clinically significant bleeding disorder (e.g., clotting factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following intramuscular injections or venipuncture. receiving systemic immunomodulatory therapy or history of receiving chemotherapy in the last 5 years other than topical agents. receipt of systemic glucocorticoids (a dose ≥20 mg/day prednisone or equivalent for 14 days) within 1 month, or any other cytotoxic or immunosuppressive drug within 6 months prior to injection of study vaccine. cancer diagnosis in the last 5 years, excluding basal cell and squamous cell carcinoma of the skin, which are allowed. presence of autoimmune disease. receipt of any investigational drug within 6 months. receipt of any non-covid-19 authorized vaccines, for example influenza, within 2 weeks of receiving study dose injection. receipt of any other experimental sars-cov-2/covid-19 or other experimental coronavirus vaccine(s) at any time prior to or during the study. exception: receipt of sars cov 2/covid-19 vaccines at least 6 months prior to day 0 that were experimental at the time of their administration but are currently authorized will not lead to exclusion. receipt of blood products or immunoglobulin (ivig or imig) within 3 months of study entry/baseline serologic evaluation. current anti-tuberculosis therapy. history of any reaction or hypersensitivity likely to be exacerbated by any component of the study vaccine. hematologic or biochemical laboratory abnormalities (blood or urine), as defined by lab normal ranges. to exclude transient abnormalities, the investigator may repeat a test once, and if the repeat test is normal according to local reference ranges, participant may be enrolled. abnormalities of laboratory values will not be exclusionary if considered not clinically significant by the investigator. previous (within 6 months prior to day 0) sars-cov-2 infection, based on a documented positive polymerase chain reaction (pcr) test or rapid antigen test, or reported by participant or prior medical history reports (not applicable for subjects in exploratory phase 2 study arm). member of the study personnel, or immediate family member or household member of the study personnel.

presence of any febrile illness or any known or suspected acute illness on the day of immunization. any condition, which in the opinion of the investigator may make the participant inappropriate for the study. clinically significant bleeding disorder (e.g., clotting factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following intramuscular injections or venipuncture. receiving systemic immunosuppressive therapy or history of receiving chemotherapy in the last 5 years other than topical agents. receipt of systemic glucocorticoids (a dose ≥20 mg/day prednisone or equivalent for 14 days) within 1 month, or any other cytotoxic or immunosuppressive drug within 6 months prior to injection of study vaccine. cancer diagnosis in the last 5 years, excluding basal cell and squamous cell carcinoma of the skin, which are allowed. presence of autoimmune disease. receipt of any investigational drug within 6 months. receipt of any non-covid-19 authorized vaccines, for example influenza, within 2 weeks of receiving study dose injection. receipt of any other experimental sars-cov-2/covid-19 or other experimental coronavirus vaccine(s) at any time prior to or during the study. receipt of blood products or immunoglobulin (ivig or imig) within 3 months of study entry/baseline serologic evaluation. current anti-tuberculosis therapy. history of any reaction or hypersensitivity likely to be exacerbated by any component of the study vaccine. hematologic or biochemical laboratory abnormalities (blood or urine), as defined by lab normal ranges. to exclude transient abnormalities, the investigator may repeat a test once, and if the repeat test is normal according to local reference ranges, participant may be enrolled. grade 1 abnormalities of laboratory values will not be exclusionary if considered not clinically significant by the investigator. known current or previous laboratory-confirmed sars-cov-1 or sars-cov-2 infection, as documented by a positive polymerase chain reaction (pcr) test from a nasal swab (not applicable for subjects in exploratory phase 2 study arm). exploratory phase 2 study arm: known current or previous laboratory-confirmed sars-cov-1 infection, and known current laboratory-confirmed sars-cov-2 infection, as documented by a positive polymerase chain reaction (pcr) test from a nasal swab.

presence of any febrile illness or any known or suspected acute illness on the day of immunization. any condition, which in the opinion of the investigator may make the participant inappropriate for the study. clinically significant bleeding disorder (e.g., clotting factor deficiency, coagulopathy or platelet disorder), or prior history of significant bleeding or bruising following intramuscular injections or venipuncture. receiving systemic immunosuppressive therapy or history of receiving chemotherapy in the last 5 years other than topical agents. receipt of systemic glucocorticoids (a dose ≥20 mg/day prednisone or equivalent for 14 days) within 1 month, or any other cytotoxic or immunosuppressive drug within 6 months prior to injection of study vaccine. cancer diagnosis in the last 5 years, excluding basal cell and squamous cell carcinoma of the skin, which are allowed. presence of autoimmune disease. receipt of any investigational drug within 6 months. receipt of any non-covid-19 authorized vaccines, for example influenza, within 2 weeks of receiving study dose injection. receipt of any other experimental sars-cov-2/covid-19 or other experimental coronavirus vaccine(s) at any time prior to or during the study. receipt of blood products or immunoglobulin (ivig or imig) within 3 months of study entry/baseline serologic evaluation. current anti-tuberculosis therapy. history of any reaction or hypersensitivity likely to be exacerbated by any component of the study vaccine. hematologic or biochemical laboratory abnormalities (blood or urine), as defined by lab normal ranges. to exclude transient abnormalities, the investigator may repeat a test once, and if the repeat test is normal according to local reference ranges, participant may be enrolled. grade 1 abnormalities of laboratory values will not be exclusionary if considered not clinically significant by the investigator. known current or previous laboratory-confirmed sars-cov-1 or sars-cov-2 infection, as documented by a positive polymerase chain reaction (pcr) test from a nasal swab (not applicable for subjects in exploratory phase 2 study arm). exploratory phase 2 study arm: known current or previous laboratory-confirmed sars-cov-1 infection, and known current laboratory-confirmed sars-cov-2 infection, as documented by a positive polymerase chain reaction (pcr) test from a nasal swab.