Study to Evaluate the Safety, Immunogenicity, and Efficacy of Nanocovax Vaccine Against COVID-19

Inclusion Criteria: * Be a male or female 18 years of age or older. * For females: Be of non-childbearing potential or willing to use appropriate contraceptive measures for 30 days prior to vaccination through 6 months after completion of the vaccine series. * Willingness to provide a signed, printed, and dated informed consent form. * Able and willing to participate in all activities in the clinical trial. * Participants with HIV, HBV, HCV should have a health record, determined to be stable for 6 months prior to the screening. Exclusion Criteria: * Participants with unstable pre-existing medical conditions over the three months before enrollment (condition that has worsened to require hospitalization or significant changes in therapy). * Planned administration/administration of a vaccine not foreseen by the study protocol from within 45 days before the first dose of study vaccine. * Previous vaccination with any Covid-19 vaccine. * History of COVID-19 disease. * History of allergic reactions or anaphylaxis to previous immunizations or allergies to any components of the vaccine. * Planning to become pregnant or planning to discontinue contraceptive precautions during the vaccination phase through 6 months after the second immunization. * History of bleeding disorders/hemostasis or use of anticoagulants. * Currently having cancer or undergoing cancer treatment. * Chronic administration (defined as more than 14 days) of immunosuppressants or other immune-modifying drugs within 3 months prior to the first vaccine dose (inhaled and topical steroids are allowed). * Women who are pregnant or breastfeeding.