AZD7442 - a Potential Combination Therapy for the Prevention and Treatment of COVID-19

Inclusion Criteria: * Written informed consent and any locally required authorisation obtained from the participant prior to performing any protocol-related procedures, including screening evaluations. * Negative SARS-CoV-2 qRT-PCR and/or serology tests prior to randomisation. * Weight ≥ 50 kg and ≤ 110 kg at screening, including a BMI of ≥ 18.0 to ≤ 30.0 kg/m\^2. * Healthy by medical history, physical examination, and baseline safety laboratory studies, according to the judgement of the PI. * Electrocardiogram without clinically significant abnormalities at screening. * Able to complete the Follow-up Period through Day 361. * Females of childbearing potential who are sexually active with a non-sterilised male partner must have used a highly effective method of contraception for at least 28 days prior to dosing with IMP and must agree to continue using such precautions until the Final Follow-up Visit. Periodic abstinence, the rhythm method, and the withdrawal method are not acceptable methods of contraception. Exclusion Criteria: * Known hypersensitivity to any component of the IMP. * History of allergic disease or reactions likely to be exacerbated by any component of the IMP. * Previous hypersensitivity, infusion-related reaction or severe adverse reaction following administration of a mAbs. * Acute (time-limited) illness, including fever above 37.5°C (99.5 °F), on day prior to or day of planned dosing; participants excluded for transient acute illness may be dosed if illness resolves within the 27-day Screening Period or may be rescreened once. * Any drug therapy within 7 days prior to Day 1 (except contraceptives or a single use of acetaminophen, aspirin, antihistamine, or combination over the counter (OTC) product that contains acetaminophen with an antihistamine, or OTC nonsteroidal anti-inflammatory agent at a dose equal to or lower than that recommended on the package). Vitamins and other nutritional supplements that are not newly introduced, ie, have been taken for at least 30 days prior to enrolment, are not exclusionary. * Blood drawn in excess of a total of 450 mL (1 unit) for any reason within 2 months prior to screening. * Receipt of immunoglobulin or blood products within 6 months prior to screening. * SARS CoV-2 or COVID-19: * Participants with any confirmed current or previous COVID-19 infection before randomisation. * Participant has clinical signs and symptoms consistent with COVID-19, eg, fever, dry cough, dyspnoea, sore throat, fatigue or confirmed infection by appropriate laboratory test within the last 4 weeks prior to screening or on admission. * Any prior receipt of investigational or licensed vaccine indicated for the prevention of SARS CoV-2 or COVID-19 or expected receipt during the period of study follow up. * Receipt of any IMP in the preceding 90 days or expected receipt of IMP during the period of study follow-up, or concurrent participation in another interventional study. * Previous receipt of a mAb within 6 months, or five antibody half lives (whichever is longer), prior to study start. * Immunodeficiency due to illness, including Human immunodeficiency virus (HIV) infection, or due to drugs, including any course of glucocorticoid therapy exceeding 2 weeks of prednisone or equivalent at a dose of 20 mg daily or every other day within 6 months prior to screening. HIV testing must be negative at screening. * Either history of active infection with hepatitis B or C or positive test for hepatitis C or for hepatitis B surface antigen at screening. * History of infection with SARS or MERS. * Aspartate aminotransferase, ALT, or serum creatinine above the ULN; bilirubin and ALP \>1.5 × ULN. * Haemoglobin or platelet count below the LLN at screening. White blood cell or neutrophil count outside normal references ranges. * History of malignancy. * Any laboratory value in the screening panel that, in the opinion of the PI, is clinically significant or might confound analysis of study results. * Pregnant or nursing female. * History of alcohol or drug abuse within the past 2 years that, according to the PI, might affect assessments of safety or ability of participant to comply with all study requirements OR positive urine drug or alcohol screening. * Any condition that, in the opinion of the PI, might compromise participant safety or interfere with evaluation of the IMP or interpretation of participant safety or study results. * Employees of the sponsor, clinical study site, or any other individuals involved with the conduct of the study, or immediate family members of such individuals. * Absence of suitable veins for blood sampling (IM and IV cohorts) and administration of IMP (IV cohorts).