inclusion criteria: signed informed consent prior to any study-related procedure; subjects must have received a complete primary vaccination schedule and a third booster dose with registered and commercial vaccine(s) against sars-cov-2, of which the last dose was given at least 4 months prior to study vaccination (maximum of 1,000 iu of anti-s igg); healthy males and females, 18-55 years of age, inclusive at screening; body mass index (bmi) ≥ 18.0 and < 30.0 kg/m2; good health, based upon the results of medical history, physical examination, vital signs, laboratory profiles of both blood and urine, and according to the clinical judgement of the investigator; female participants of childbearing potential must be willing to comply with effective contraception up to 90 days after the study vaccine administration; willing to comply with the study procedures.

inclusion criteria: signed informed consent prior to any study-related procedure; subjects must have received a complete primary vaccination schedule and a third booster dose with registered and commercial vaccine(s) against sars-cov-2, of which the last dose was given at least 4 months prior to study vaccination (maximum of 1,000 iu of anti-s igg); healthy males and females, 18-55 years of age, inclusive at screening; body mass index (bmi) ≥ 18.0 and < 30.0 kg/m2; good health, based upon the results of medical history, physical examination, vital signs, laboratory profiles of both blood and urine, and according to the clinical judgement of the investigator; female participants of childbearing potential must be willing to comply with effective contraception up to 90 days after the study vaccine administration; willing to comply with the study procedures.