1. Volunteers (male or female) non-COVID-19 infected. 2. Aged greater than or equal to 18 years. 3. No medical history of SARS-CoV-2 infection within 4 months of Day 1. 4. The subject (or subject’s legally authorised representative) has provided voluntary signed informed consent. 5. Subject should be willing to comply with protocol scheduled study visits or procedures, to the best of the subject and Investigator’s knowledge. 6. Have a baseline body temperature of less than or equal to 37·5°C and have general good health as established by medical history and physical examination. 7. Reproductive criteria as follows: • Female subjects who are of non-reproductive potential (i.e., post menopausal by history - no menses for greater than or equal to 1 year and follicle-stimulating hormone (FSH) level consistent with post-menopausal status, OR history of hysterectomy, OR history of bilateral tubal ligation, OR history of bilateral oophorectomy). • Female subjects of childbearing potential must have a negative serum pregnancy test within 14 days of the first dose. • Female subjects must be willing to use highly effective methods of birth control during the period of therapy and for 6 months following the last study drug administration. Highly effective methods of birth control include sexual abstinence, hormonal birth control, or intrauterine device (women), vasectomy or a condom with spermicide (men) in combination with barrier methods. • Male subjects must be willing to use highly effective methods of birth control during the period of therapy and for 6 months following the last study drug administration. • All study subjects must be willing to ensure that corresponding sexual partners practice these same methods of highly effective birth control for the same duration.

1. Volunteers (male or female) non-COVID-19 infected. 2. Aged greater than or equal to 18 years. 3. No medical history of SARS-CoV-2 infection within 4 months of Day 1. 4. The subject (or subject’s legally authorised representative) has provided voluntary signed informed consent. 5. Subject should be willing to comply with protocol scheduled study visits or procedures, to the best of the subject and Investigator’s knowledge. 6. Have a baseline body temperature of less than or equal to 37·5°C and have general good health as established by medical history and physical examination. 7. Reproductive criteria as follows: • Female subjects who are of non-reproductive potential (i.e., post menopausal by history - no menses for greater than or equal to 1 year and follicle-stimulating hormone (FSH) level consistent with post-menopausal status, OR history of hysterectomy, OR history of bilateral tubal ligation, OR history of bilateral oophorectomy). • Female subjects of childbearing potential must have a negative serum pregnancy test within 14 days of the first dose. • Female subjects must be willing to use highly effective methods of birth control during the period of therapy and for 6 months following the last study drug administration. Highly effective methods of birth control include sexual abstinence, hormonal birth control, or intrauterine device (women), vasectomy or a condom with spermicide (men) in combination with barrier methods. • Male subjects must be willing to use highly effective methods of birth control during the period of therapy and for 6 months following the last study drug administration. • All study subjects must be willing to ensure that corresponding sexual partners practice these same methods of highly effective birth control for the same duration.

1. Volunteers (male or female) non-COVID-19 infected. 2. Aged greater than or equal to 18 years. 3. No medical history of SARS-CoV-2 infection. 4. The subject (or subject’s legally authorised representative) has provided voluntary signed informed consent. 5. Subject should be willing to comply with protocol scheduled study visits or procedures, to the best of the subject and Investigator’s knowledge. 6. Have a baseline body temperature of less than or equal to 37·5°C and have general good health as established by medical history and physical examination. 7. Reproductive criteria as follows: • Female subjects who are of non-reproductive potential (i.e., post menopausal by history - no menses for greater than or equal to 1 year and follicle-stimulating hormone (FSH) level consistent with post-menopausal status, OR history of hysterectomy, OR history of bilateral tubal ligation, OR history of bilateral oophorectomy). • Female subjects of childbearing potential must have a negative serum pregnancy test within 14 days of the first dose. • Female subjects must be willing to use highly effective methods of birth control during the period of therapy and for 6 months following the last study drug administration. Highly effective methods of birth control include sexual abstinence, hormonal birth control, or intrauterine device (women), vasectomy or a condom with spermicide (men) in combination with barrier methods. • Male subjects must be willing to use highly effective methods of birth control during the period of therapy and for 6 months following the last study drug administration. • All study subjects must be willing to ensure that corresponding sexual partners practice these same methods of highly effective birth control for the same duration.

1. Volunteers (male or female) non-COVID-19 infected. 2. Aged greater than or equal to 18 years. 3. No medical history of SARS-CoV-2 infection. 4. The subject (or subject’s legally authorised representative) has provided voluntary signed informed consent. 5. Subject should be willing to comply with protocol scheduled study visits or procedures, to the best of the subject and Investigator’s knowledge. 6. Have a baseline body temperature of less than or equal to 37·5°C and have general good health as established by medical history and physical examination. 7. Reproductive criteria as follows: • Female subjects who are of non-reproductive potential (i.e., post menopausal by history - no menses for greater than or equal to 1 year and follicle-stimulating hormone (FSH) level consistent with post-menopausal status, OR history of hysterectomy, OR history of bilateral tubal ligation, OR history of bilateral oophorectomy). • Female subjects of childbearing potential must have a negative serum pregnancy test within 14 days of the first dose. • Female subjects must be willing to use highly effective methods of birth control during the period of therapy and for 6 months following the last study drug administration. Highly effective methods of birth control include sexual abstinence, hormonal birth control, or intrauterine device (women), vasectomy or a condom with spermicide (men) in combination with barrier methods. • Male subjects must be willing to use highly effective methods of birth control during the period of therapy and for 6 months following the last study drug administration. • All study subjects must be willing to ensure that corresponding sexual partners practice these same methods of highly effective birth control for the same duration.

1. Volunteers (male or female) non-COVID-19 infected. 2. Aged greater than or equal to 18 years. 3. No medical history of SARS-CoV-2 infection. 4. The subject (or subject’s legally authorised representative) has provided voluntary signed informed consent. 5. Subject should be willing to comply with protocol scheduled study visits or procedures, to the best of the subject and Investigator’s knowledge. 6. Have a baseline body temperature of less than or equal to 37·5°C and have general good health as established by medical history and physical examination. 7. Negative anti-COVID-19 serum antibodies (IgG and IgM) 8. Reproductive criteria as follows: • Female subjects who are of non-reproductive potential (i.e., post menopausal by history - no menses for greater than or equal to 1 year and follicle-stimulating hormone (FSH) level consistent with post-menopausal status, OR history of hysterectomy, OR history of bilateral tubal ligation, OR history of bilateral oophorectomy). • Female subjects of childbearing potential must have a negative serum pregnancy test within 14 days of the first dose. • Female subjects must be willing to use highly effective methods of birth control during the period of therapy and for 6 months following the last study drug administration. Highly effective methods of birth control include sexual abstinence, hormonal birth control, or intrauterine device (women), vasectomy or a condom with spermicide (men) in combination with barrier methods. • Male subjects must be willing to use highly effective methods of birth control during the period of therapy and for 6 months following the last study drug administration. • All study subjects must be willing to ensure that corresponding sexual partners practice these same methods of highly effective birth control for the same duration.

1. Volunteers (male or female) non-COVID-19 infected. 2. Aged greater than or equal to 18 years. 3. No medical history of SARS-CoV-2 infection. 4. The subject (or subject’s legally authorised representative) has provided voluntary signed informed consent. 5. Subject should be willing to comply with protocol scheduled study visits or procedures, to the best of the subject and Investigator’s knowledge. 6. Have a baseline body temperature of less than or equal to 37·5°C and have general good health as established by medical history and physical examination. 7. Negative anti-COVID-19 serum antibodies (IgG and IgM) 8. Reproductive criteria as follows: • Female subjects who are of non-reproductive potential (i.e., post menopausal by history - no menses for greater than or equal to 1 year and follicle-stimulating hormone (FSH) level consistent with post-menopausal status, OR history of hysterectomy, OR history of bilateral tubal ligation, OR history of bilateral oophorectomy). • Female subjects of childbearing potential must have a negative serum pregnancy test within 14 days of the first dose. • Female subjects must be willing to use highly effective methods of birth control during the period of therapy and for 6 months following the last study drug administration. Highly effective methods of birth control include sexual abstinence, hormonal birth control, or intrauterine device (women), vasectomy or a condom with spermicide (men) in combination with barrier methods. • Male subjects must be willing to use highly effective methods of birth control during the period of therapy and for 6 months following the last study drug administration. • All study subjects must be willing to ensure that corresponding sexual partners practice these same methods of highly effective birth control for the same duration.