Inclusion Criteria:
- Adult, ≥ 18 years at the time of signing the informed consent.
- Cohort specific inclusion criteria:
Solid organ transplant
- Participants with heart, lung, kidney, or liver transplant, and are stable on immunosuppressants (defined as no change in dose in the previous 4 weeks).
Hematopoietic stem cell transplant
- Participants with autologous (up to 6 months after transplantation) or allogeneic stem cell transplant who are immunosuppressed, with no evidence of active graft-versushost disease, at least one month after the procedure.
Cancer patients on chemotherapy
- Participants with solid tumors (except breast cancer), histologically diagnosed, who were undergoing intravenous cytotoxic chemotherapy within the last 6 months, who received at least 1 cycle prior to cytotoxic chemotherapy, and have a life expectancy of longer than 3 months.
Chronic inflammatory conditions
- Participants with chronic inflammatory conditions, including those on immunosuppressant medications, can be recruited. The following conditions are specifically excluded: multiple sclerosis and peripheral demyelinating disease.
Primary immune deficiency
- Examples include combined granulomatous disorder, SCID, common variable immunodeficiency.
Immunocompetent:
- No confirmed or suspected immunosuppressive or immunodeficient state.
- No use of immunosuppressant medication within the past 1 month (≥ 20 mg per day of prednisone or its equivalent, given daily or on alternate days for ≥ 15 days within 30 days prior to administration of AZD1222). The following exceptions are permitted: topical/inhaled steroids or short-term oral steroids (course lasting ≤ 14 days).
- No receipt of immunoglobulins and/or any blood products within 3 months prior to administration of AZD1222 or expected receipt during the period of study follow up.
- No severe and/or uncontrolled cardiovascular disease, respiratory disease, gastrointestinal disease, liver disease, renal disease, endocrine disorder, and neurological illness, as judged by the Investigator.
Exclusion Criteria:
- History of allergic disease or reactions likely to be exacerbated by any component of AZD1222.
- Active infection with SARS-CoV-2 as confirmed locally by nucleic acid amplification test (e.g. RT-PCR).
- Known current or past laboratory-confirmed SARS-CoV-2 infection.
- Significant infection or other acute illness, including fever (temperature > 37.8°C) on the day prior to or day of first dosing.
- Thrombocytopenia with platelet count ≤ 75,000 x 109/microliter based on complete blood count test at screening visit.
- HIV-positive participants based on a positive ELISA test performed at screening visit.
- History of cerebral venous sinus thrombosis (CVST).
- Receipt of any vaccine (licensed or investigational) within 30 days prior to and after administration of AZD1222.