inclusion criteria: 1. must provide documented informed consent prior to any study procedures being performed 2. is capable of understanding and agrees to comply with planned study procedures and to be available for all study visits 3. has received at least 2 doses of comirnaty or moderna covid-19 vaccine (spikevax®), with the last dose of vaccine received at least 6 months prior to screening 4. negative for sars-cov-2 infection by rt-pcr test at screening 5. is a male or nonpregnant female ≥18 years old 6. if the participant is a woman of child bearing potential, the participant agrees to use at least 1 highly effective form of contraception for at least 30 days prior to the study vaccination up to 3 months after study vaccination. 7. agrees to refrain from blood or plasma donation from the first study vaccination through end of study. 8. has a body mass index of 18 to 40 kg/m2, inclusive, at screening. 9. is healthy or medically stable as determined by investigator judgment based on medical history, clinical laboratory tests, vital sign measurements, and physical examination findings

inclusion criteria: 1. must provide documented informed consent prior to any study procedures being performed 2. is capable of understanding and agrees to comply with planned study procedures and to be available for all study visits 3. has received at least 2 doses of comirnaty or moderna covid-19 vaccine (spikevax®), with the last dose of vaccine received at least 6 months prior to screening 4. negative for sars-cov-2 infection by rt-pcr test at screening 5. is a male or nonpregnant female ≥18 years old 6. if the participant is a woman of child bearing potential, the participant agrees to use at least 1 highly effective form of contraception for at least 30 days prior to the study vaccination up to 3 months after study vaccination. 7. agrees to refrain from blood or plasma donation from the first study vaccination through end of study. 8. has a body mass index of 18 to 40 kg/m2, inclusive, at screening. 9. is healthy or medically stable as determined by investigator judgment based on medical history, clinical laboratory tests, vital sign measurements, and physical examination findings

inclusion criteria: must provide documented informed consent prior to any study procedures being performed is capable of understanding and agrees to comply with planned study procedures and to be available for all study visits has received at least 2 doses of comirnaty or moderna covid-19 vaccine (spikevax®), with the last dose of vaccine received at least 6 months prior to screening negative for sars-cov-2 infection by rt-pcr test at screening is a male or nonpregnant female ≥18 years old if the participant is a woman of child bearing potential, the participant agrees to use at least 1 highly effective form of contraception for at least 30 days prior to the study vaccination up to 3 months after study vaccination. agrees to refrain from blood or plasma donation from the first study vaccination through end of study. has a body mass index of 18 to 40 kg/m2, inclusive, at screening. is healthy or medically stable as determined by investigator judgment based on medical history, clinical laboratory tests, vital sign measurements, and physical examination findings

inclusion criteria: must provide documented informed consent prior to any study procedures being performed is capable of understanding and agrees to comply with planned study procedures and to be available for all study visits has received at least 2 doses of comirnaty or moderna covid-19 vaccine (spikevax®), with the last dose of vaccine received at least 6 months prior to screening negative for sars-cov-2 infection by rt-pcr test at screening is a male or nonpregnant female ≥18 years old if the participant is a woman of child bearing potential, the participant agrees to use at least 1 highly effective form of contraception for at least 30 days prior to the study vaccination up to 3 months after study vaccination. agrees to refrain from blood or plasma donation from the first study vaccination through end of study. has a body mass index of 18 to 40 kg/m2, inclusive, at screening. is healthy or medically stable as determined by investigator judgment based on medical history, clinical laboratory tests, vital sign measurements, and physical examination findings