inclusion criteria: male or female participants between the ages of 18 and 60 years, inclusive, at enrolment women of child-bearing potential (wocbp) may be enrolled in the study if the participant fulfils all the following criteria: has a negative urine-based pregnancy test at screening and on the day of the first dose (day1) and second dose (day22) must practice true abstinence or, if engaged in sexual relations with a male, they must agree to use highly effective (failure rate of < 1% per year when used consistently and correctly), double-barrier contraceptive measures* from screening and for a period of at least 60 days after the last dose of investigational vaccine. is not currently breastfeeding. women of non-child-bearing potential may be enrolled in the study if the participant meet one of these following criteria: d. postmenopausal (defined as having a history of amenorrhea of at least one year), or e. history of amenorrhea is less than one year, must have an fsh level > 40 milli-international units per milliliter (miu/ml), or f. have a documented status of being surgically sterile (hysterectomy, bilateral oophorectomy, or tubal ligation/salpingectomy). males must be surgically sterile (>30 days since vasectomy with no viable sperm), practice true abstinence or, if engaged in sexual relations with a female of child-bearing potential, the participants and their partner must use an acceptable, highly effective, double-barrier contraceptive method* from screening and for a period of at least 60 days after the last dose of investigational vaccine. * the pi is to assess the adequacy of methods of contraception on a case-by-case basis. these criteria do not apply if the participants are in a same-sex relationship. type of participant and disease characteristics: participants must be able to communicate effectively with study personnel and agree to comply with the study procedures. capable to provide written informed consent. healthy participants who are determined by medical history, physical examination (if required), and clinical judgment of the investigator to be eligible for inclusion in the study. participants must have haematology, clinical chemistry, coagulation and urinalysis test results that are not deviating from the normal reference range by age and gender to a clinically relevant extent at screening.

inclusion criteria: male or female participants between the ages of 18 and 60 years, inclusive, at enrolment women of child-bearing potential (wocbp) may be enrolled in the study if the participant fulfils all the following criteria: has a negative urine-based pregnancy test at screening and on the day of the first dose (day1) and second dose (day22) must practice true abstinence or, if engaged in sexual relations with a male, they must agree to use highly effective (failure rate of < 1% per year when used consistently and correctly), double-barrier contraceptive measures* from screening and for a period of at least 60 days after the last dose of investigational vaccine. is not currently breastfeeding. women of non-child-bearing potential may be enrolled in the study if the participant meet one of these following criteria: d. postmenopausal (defined as having a history of amenorrhea of at least one year), or e. history of amenorrhea is less than one year, must have an fsh level > 40 milli-international units per milliliter (miu/ml), or f. have a documented status of being surgically sterile (hysterectomy, bilateral oophorectomy, or tubal ligation/salpingectomy). males must be surgically sterile (>30 days since vasectomy with no viable sperm), practice true abstinence or, if engaged in sexual relations with a female of child-bearing potential, the participants and their partner must use an acceptable, highly effective, double-barrier contraceptive method* from screening and for a period of at least 60 days after the last dose of investigational vaccine. * the pi is to assess the adequacy of methods of contraception on a case-by-case basis. these criteria do not apply if the participants are in a same-sex relationship. type of participant and disease characteristics: participants must be able to communicate effectively with study personnel and agree to comply with the study procedures. capable to provide written informed consent. healthy participants who are determined by medical history, physical examination (if required), and clinical judgment of the investigator to be eligible for inclusion in the study. participants must have haematology, clinical chemistry, coagulation and urinalysis test results that are not deviating from the normal reference range by age and gender to a clinically relevant extent at screening.