This is a Phase I, open label, dose-escalation study of three dose levels of the SARS-CoV-2 spike antigen administered intramuscularly (IM) in combination with a fixed dosage of PIKA adjuvant vaccine to evaluate the safety, tolerability, and immunogenicity of PIKA COVID-19 vaccine candidate in healthy individuals aged 18 years and above. The study will comprise of two arms. Arm A will include subjects who never been infected with COVID-19 or with a history of COVID-19 infection for not less than 6 months prior to study participation and Arm B will include subjects who will be receiving PIKA vaccine as a booster vaccination dose to COVID-19 primary vaccination of inactivated or mRNA Covid 19 vaccines.

This is a Phase I, open label, dose-escalation study of three dose levels of the SARS-CoV-2 spike antigen administered intramuscularly (IM) in combination with a fixed dosage of PIKA adjuvant vaccine to evaluate the safety, tolerability, and immunogenicity of PIKA COVID-19 vaccine candidate in healthy individuals aged 18 years and above. The study will comprise of two arms. Arm A will include subjects who had never been infected with COVID-19 or with a history of COVID-19 infection for not less than 6 months prior to study participation and Arm B will include subjects who will be receiving PIKA vaccine as a booster vaccination dose to COVID-19 primary vaccination of inactivated or mRNA Covid 19 vaccines.

Arm A: There will be 3 dose groups, 1 to 3 with escalating antigen dose with PIKA adjuvant in sequential cohorts. A total of 45 subjects will be enrolled in Arm A. Subjects in Group 1-3 will receive two doses of PIKA COVID-19 vaccine via IM administration on Days 0 and 7. Fifteen eligible subjects in each dose group.

Arm B: There will be 3 dose groups, 1 to 3 with escalating antigen dose with PIKA adjuvant in sequential cohorts. A total of 90 subjects will be enrolled in Arm B which will be divided into Arm B1 (45 subjects) and Arm B2 (45 subjects). Arm B1 will enroll subjects who received Inactivated vaccines and will comprise of 15 subjects per dose (45 subjects). Arm B2 will enroll subjects who received mRNA vaccines and will comprise of 15 subjects per dose (45 subjects). Subjects in Group 1-3 of Arm B1 and Arm B2 will receive one booster dose of PIKA COVID-19 vaccine via IM administration on Days 0.

Inclusion Criteria

Inclusion Criteria of Arm A:

1. Male and female healthy volunteers.
2. Age ≥18 years on Study Day 0.
3. Judged by the investigator to be healthy on the basis of medical history, physical examination and vital signs performed at screening.
4. Able to provide informed consent.
5. Able and willing to comply with all study procedures over follow-up period of approximately 6 months.
6. For more inclusion criteria, please contact the investigator or sponsor.

Inclusion Criteria of Arm B:

Male and female healthy volunteers.

1. Received complete primary series of COVID-19 Inactivated Vaccines not less than 6 months or Received complete primary series of COVID-19 mRNA Vaccines not less than 6 month.
2. Age ≥18 years on Study Day 0.
3. Judged by the investigator to be healthy on the basis of medical history, physical examination and vital signs performed at screening.
4. Able to provide informed consent .
5. Able and willing to comply with all study procedures over follow-up period of approximately 6 months.
6. For more inclusion criteria, please contact the investigator or sponsor.

Exclusion Criteria:

Exclusion Criteria of Arm A:

1. History of COVID-19 of less than 6 months prior to enrollment
2. Received partial or complete course of any type of COVID-19 vaccine.
3. History of close contact with a person infected or suspected of COVID-19 not less than 14 days prior to study enrollment.
4. Positive test for SARS-CoV-2 infection, including but not limited to RT-PCR /Rapid Antigen Test at screening, before the first dose (Day 0) and before the second dose (Day 7).
5. For more exclusion criteria, please contact the investigator or sponsor.

Exclusion Criteria of Arm B:

1. History of close contact with a person infected or suspected of COVID-19 not less than 14 days prior to study enrollment.
2. Positive test for SARS-CoV-2 infection, including but not limited to RT-PCR/RAT at screening, before the first dose (Day 0) .
3. Have received three and more doses of COVID-19 vaccine.
4. Pregnant or breastfeeding or intending to become pregnant or father children within the projected duration of the trial.
5. For more exclusion criteria, please contact the investigator or sponsor.