Clinical trial NCT04973449: Phase II/III Study of AZD2816, for the Prevention of COVID-19 in Adults
Official title: A Phase II/III Partially Double-Blinded, Randomised, Multinational, Active-Controlled Study in Both Previously Vaccinated and Unvaccinated Adults to Determine the Safety and Immunogenicity of AZD2816, a Vaccine for the Prevention of COVID-19 Caused by Variant Strains of SARS-CoV-2
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE2
PHASE3
Conditions: COVID-19
SARS-CoV-2
Keywords: COVID-19 Vaccine
Lead sponsor: AstraZeneca
Sponsor class: INDUSTRY
First posted: 2021-07-22
Enrollment: 2843
Sex: ALL
Minimum age (years): 18
Maximum age (years): 115
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Previously vaccinated individuals will receive 1 dose of

AZD1222 or AZD2816 on Day 1. Previously unvaccinated participants will receive one of the following 2-dose vaccinations:

* 1 dose of AZD2816 on Day 1 and on Day 29
* 1 dose of AZD1222 on Day1 and on Day 29
* 1 dose of AZD1222 on Day 1 and 1 dose of AZD2816 on Day 29
* 1 dose of AZD2816 on Day 1 and on Day 85. Participants will be followed up for safety for 180 days after last study vaccine administration.
Primary purpose: PREVENTION

Brief summary: The aim of the study is to assess the safety, and immunogenicity of AZD2816 for the prevention of coronavirus disease 2019 (COVID-19).

Detailed description: The purpose of this study is to demonstrate the safety and characterize the immunogenicity of AZD2816; AstraZeneca's candidate chimpanzee adenovirus Ox1 (ChAdOx1) vector vaccine against severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) variant strain B.1.351.

Eligibility criteria: Inclusion Criteria:

1. Adult, ≥ 18 years of age at the time of consent.

   For inclusion in the SARS-CoV-2 seronegative population:
2. No history of laboratory-confirmed SARS-CoV-2 infection (ie, no positive nucleic acid amplification test and no positive antibody test).
3. Seronegative for SARS-CoV-2 at screening (lateral flow test to detect reactivity to the nucleoprotein).
4. Medically stable such that, according to the judgment of the investigator, hospitalization within the study period is not anticipated and the participant appears likely to be able to remain on study through the end of protocol-specified follow-up.
5. Able to understand and comply with study requirements/procedures (if applicable, with assistance by caregiver, surrogate, or legally authorized representative) based on the assessment of the investigator.
6. Signed informed consent obtained before conducting any study-related procedures.
7. Contraceptive use by women should be consistent with local regulations regarding the methods of contraception for those participating in clinical studies.

   Previously COVID-19 Vaccinated Participants:
8. Prior completion of a 2-dose primary homologous vaccination regimen against SARSCoV-2 with either AZD1222 (2 standard doses as authorized vaccine or as investigational product in a clinical trial with a 4 to 12-week dosing interval) or with an mRNA vaccine approved for emergency or conditional use. The second dose in all cases should have been administered at least 3 months prior to first administration of study intervention.

Exclusion Criteria:

1. History of allergy to any component of AZD1222/AZD2816.
2. History of Guillain-Barré syndrome, any demyelinating disease, or any other neuroimmunologic condition.
3. Significant infection or other acute illness, including fever \> 100 °F (\> 37.8 °C) on the day prior to or day of randomization.
4. Any confirmed or suspected immunosuppressive or immunodeficient state, including asplenia or human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS).
5. Recurrent severe infections and use of immunosuppressant medication within the past 6 months (≥ 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 study intervention). The following exceptions are permitted: Topical/inhaled steroids or short-term oral steroids (course lasting ≤ 14 days).
6. History of primary malignancy (see protocol).
7. History of thrombocytopenia and/or thrombosis, including participants who have experienced major venous and/or arterial thrombosis in combination with thrombocytopenia following vaccination with any COVID-19 vaccine.
8. History of heparin-induced thrombocytopenia, congenital thrombophilia (ie, factor V Leiden, prothrombin G20210A, antithrombin III deficiency, protein C deficiency and protein S deficiency, factor XIII mutation, familial dysfibrinogenemia), auto-immune thrombophilia (antiphospholipid syndrome, anti-cardiolipin antibodies, anti-β2- glycoprotein 1 antibodies), or paroxysmal nocturnal haemoglobinuria.
9. Clinically significant bleeding (eg, factor deficiency, coagulopathy, or platelet disorder), or prior history of significant bleeding or bruising following intramuscular injections or venepuncture.
10. Severe and/or uncontrolled cardiovascular disease, respiratory disease, gastrointestinal disease, liver disease, renal disease, endocrine disorder, or neurological illness, as judged by the Investigator.
11. Any other significant disease, disorder, or finding that may significantly increase the risk to the participant because of participation in the study, affect the ability of the participant to participate in the study, or impair interpretation of the study data.
12. Any autoimmune conditions, except mild psoriasis and vitiligo.

Primary outcomes:
measure: Number of Participants With Local and Systemic Solicited Treatment Emergent Adverse Events (TEAEs) in Primary Vaccination Cohort (PVC):- AZD2816 (4), Booster Cohorts:-AZD1222:AZD2816, and mRNA:AZD2816
timeFrame: During the 7-day follow-up period after vaccination (vaccines administered on Days 1 and 29 [only for primary vaccination cohort])
measure: Number of Participants With Unsolicited TEAEs, Treatment-emergent Serious AEs (TESAEs), Medically Attended AEs (MAAEs), and Adverse Events of Special Interest (AESIs) in PVC:- AZD2816 (4), Booster Cohorts:- AZD1222:AZD2816, and mRNA:AZD2816
timeFrame: During the 28-day follow-up period after vaccination (vaccines administered on Days 1 and 29 [only for primary vaccination cohort])
measure: Number of Participants With Abnormal Laboratory Parameters Reported as TEAEs in Primary Vaccination Cohort:- AZD2816 (4), Booster Cohorts:-AZD1222:AZD2816 and mRNA:AZD2816
timeFrame: During the 28-day follow-up period after vaccination (vaccines administered on Days 1 and 29 [only for primary vaccination cohort])
measure: Geometric Mean Titre (GMT) of SARS-CoV-2 Neutralizing Antibodies (nAb) Against B.1.351 Variant Elicited by Primary Vaccination Cohort:- AZD2816 (4) and the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- AZD1222:AZD1222 and AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against the B.1.351 Variant Elicited by Primary Vaccination Cohort:- AZD2816 (4) and the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- mRNA:AZD1222 and AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
Secondary outcomes:
measure: Number of Participants With Local and Systemic Solicited TEAEs
timeFrame: During the 7-day follow-up period after vaccination (vaccines administered on Days 1 and 29 or Day 85 [only for primary vaccination cohorts])
measure: Number of Participants With Unsolicited TEAEs, TESAEs, MAAEs, and AESIs
timeFrame: During the 28-day follow-up period after vaccination (vaccines administered on Days 1 and 29 or Day 85 [only for primary vaccination cohorts])
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Primary Vaccination Cohort:- AZD2816 (4) and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Primary Vaccination Cohort:- AZD1222 + AZD2816 (4) and the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD2816 (4) and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- AZD1222:AZD2816 and the Original Wuhan-Hu-1 Strain Elicited by AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- AZD1222:AZD2816 and Booster Cohort:- AZD1222:AZD1222
timeFrame: 28 days after booster dose (Day 29)
measure: GMT of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- AZD1222:AZD2816 and AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- AZD1222:AZD2816 and Booster Cohort:- AZD1222:AZD1222
timeFrame: 28 days after booster dose (Day 29)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- AZD1222:AZD2816 and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Primary Vaccination Cohort: 28 days after the second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- mRNA:AZD2816 and the Original Wuhan-Hu-1 Strain Elicited by AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- mRNA:AZD2816 and Booster Cohort:- mRNA:AZD1222
timeFrame: 28 days after booster dose (Day 29)
measure: GMT of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- mRNA:AZD2816 and AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- mRNA:AZD2816 and Booster Cohort:- mRNA:AZD1222
timeFrame: 28 days after booster dose (Day 29)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- mRNA:AZD2816 and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Primary Vaccination Cohort: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- AZD1222:AZD2816 and the Original Wuhan-Hu-1 Strain Elicited by AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- AZD1222:AZD2816 and Booster Cohort:- AZD1222:AZD1222
timeFrame: 28 days after booster dose (Day 29)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- AZD1222:AZD2816 and AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- AZD1222:AZD2816 and Booster Cohort:- AZD1222:AZD1222
timeFrame: 28 days after booster dose (Day 29)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- AZD1222:AZD2816 and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Primary Vaccination Cohort: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- mRNA:AZD2816 and the Original Wuhan-Hu-1 Strain Elicited by AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- mRNA:AZD2816 and Booster Cohort:- mRNA:AZD1222
timeFrame: 28 days after booster dose (Day 29)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- mRNA:AZD2816 and AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- mRNA:AZD2816 and Booster Cohort:- mRNA:AZD1222
timeFrame: 28 days after booster dose (Day 29)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- mRNA:AZD2816 and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Primary Vaccination Cohort: 28 days after the second dose (Day 57)
measure: Number of Participants With TESAEs, MAAEs, and AESIs From Day 1 Through 6 Months Post Last Dose
timeFrame: During the 6 months follow-up period after vaccination (vaccines administered on Days 1 and 29 or Day 85 [only for primary vaccination cohorts])
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Primary Vaccination Cohort:- AZD1222 + AZD2816 (4) and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD1222 + AZD2816 (4) and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant and the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD2816 (4)
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against the B.1.351 Variant and the Original Wuhan-Hu-1 Strain by Primary Vaccination Cohort:- AZD1222 + AZD2816 (4)
timeFrame: 28 days after second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Primary Vaccination Cohort:- AZD2816 (4) and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: 28 days after second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD2816 (4) and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: 28 days after second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Primary Vaccination Cohort:- AZD1222 + AZD2816 (4) and the Original Wuhan Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: 28 days after second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Primary Vaccination Cohort:- AZD1222 + AZD2816 (4) and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: 28 days after second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD1222 + AZD2816 (4) and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: 28 days after second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant and the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD2816 (4)
timeFrame: 28 days after second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant and the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD1222 + AZD2816 (4)
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- AZD1222:AZD1222 and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Primary Vaccination Cohort: 28 days after the second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- AZD1222:AZD1222 and the Original Wuhan-Hu-1 Strain Elicited by AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against the B.1.351 Variant and the Original Wuhan-Hu-1 Strain by Booster Cohort:- AZD1222:AZD2816
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against the B.1.351 Variant and the Original Wuhan-Hu-1 Strain by Booster Cohort:- AZD1222:AZD1222
timeFrame: 28 days after second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- AZD1222:AZD1222 and AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- AZD1222:AZD1222 and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Primary Vaccination Cohort: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- AZD1222:AZD1222 and the Original Wuhan-Hu-1 Strain Elicited by AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant and the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- AZD1222:AZD2816
timeFrame: 28 days after second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant and the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- AZD1222:AZD1222
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- mRNA:AZD1222 and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Primary Vaccination Cohort: 28 days after the second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- mRNA:AZD1222 and the Original Wuhan-Hu-1 Strain Elicited by AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against the B.1.351 Variant and the Original Wuhan-Hu-1 Strain by Booster Cohort:- mRNA:AZD2816
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against the B.1.351 Variant and the Original Wuhan-Hu-1 Strain by Booster Cohort:- mRNA:AZD1222
timeFrame: 28 days after second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- mRNA:AZD1222 and AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- mRNA:AZD1222 and Primary Vaccination Cohort:- AZD1222 (4)
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Primary Vaccination Cohort: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Booster Cohort:- mRNA:AZD1222 and the Original Wuhan-Hu-1 Strain Elicited by AZD1222 in Historical Control
timeFrame: Booster Cohort: 28 days after booster dose (Day 29) and Historical Control: 28 days after the second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant and the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- mRNA:AZD2816
timeFrame: 28 days after second dose (Day 57)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 nAb Against B.1.351 Variant and the Original Wuhan-Hu-1 Strain Elicited by Booster Cohort:- mRNA:AZD1222
timeFrame: 28 days after second dose (Day 57)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Primary Vaccination Cohort:- AZD2816 (4) and the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD1222 (4) on Day 29
timeFrame: 28 days after first dose (Day 29)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Primary Vaccination Cohort:- AZD2816 (4) and Primary Vaccination Cohort:- AZD1222 (4) on Day 29
timeFrame: 28 days after first dose (Day 29)
measure: GMT of SARS-CoV-2 nAb Against B.1.351 Variant Elicited by Primary Vaccination Cohort:- AZD1222 + AZD2816 (4) and the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD1222 (4) on Day 29
timeFrame: 28 days after first dose (Day 29)
measure: GMT of SARS-CoV-2 nAb Against the Original Wuhan-Hu-1 Strain Elicited by Primary Vaccination Cohort:- AZD2816 (4) and Primary Vaccination Cohort:- AZD1222 (4) on Day 29
timeFrame: 28 days after first dose (Day 29)
measure: GMT of ChAdOx1 nAb in Primary Vaccination Cohorts and Following a Booster Dose of AZD2816
timeFrame: Booster Cohorts: 28 days after booster dose (Day 29) and Primary Vaccination Cohorts: 28 days after the second dose (Day 57 for 4-week dosing interval cohorts and Day 113 for 12-week dosing interval cohort)
measure: Percentage of Participants With Seroresponse of ChAdOx1 nAb in Primary Vaccination Cohorts and Following a Booster Dose of AZD2816
timeFrame: Booster Cohorts: 28 days after booster dose (Day 29) and Primary Vaccination Cohorts: 28 days after the second dose (Day 57 for 4-week dosing interval cohorts and Day 113 for 12-week dosing interval cohort)
measure: GMT of SARS-CoV-2 Spike Protein Binding Antibodies in Primary Vaccination Cohorts and Booster Cohorts
timeFrame: Booster Cohorts: 28 days after booster dose (Day 29) and Primary Vaccination Cohorts: 28 days after the second dose (Day 57 for 4-week dosing interval cohorts and Day 113 for 12-week dosing interval cohort)
measure: Percentage of Participants With Seroresponse of SARS-CoV-2 Spike Protein Binding Antibodies in Primary Vaccination Cohorts and Booster Cohorts
timeFrame: Booster Cohorts: 28 days after booster dose (Day 29) and Primary Vaccination Cohorts: 28 days after the second dose (Day 57 for 4-week dosing interval cohorts and Day 113 for 12-week dosing interval cohort)
measure: Correlation Between ChAdOx1 nAb and SARS-CoV-2 nAb Titres
timeFrame: Booster Cohorts: 28 days after booster dose (Day 29) and Primary Vaccination Cohorts: 28 days after the second dose (Day 57 for 4-week dosing interval cohorts and Day 113 for 12-week dosing interval cohort)
Other outcomes:
Locations:
city: Brasilia
country: Brazil
facility: Research Site
city: Curitiba
country: Brazil
facility: Research Site
city: Natal
country: Brazil
facility: Research Site
city: Natal
country: Brazil
facility: Research Site
city: Porto Alegre
country: Brazil
facility: Research Site
city: Salvador
country: Brazil
facility: Research Site
city: Lublin
country: Poland
facility: Research Site
city: Oświęcim
country: Poland
facility: Research Site
city: Puławy
country: Poland
facility: Research Site
city: Zamosc
country: Poland
facility: Research Site
city: Bloemfontein
country: South Africa
facility: Research Site
city: Cape Town
country: South Africa
facility: Research Site
city: Johannesburg
country: South Africa
facility: Research Site
city: Johannesburg
country: South Africa
facility: Research Site
city: Johannesburg
country: South Africa
facility: Research Site
city: Somerset West
country: South Africa
facility: Research Site
city: Birmingham
country: United Kingdom
facility: Research Site
city: Bournemouth
country: United Kingdom
facility: Research Site
city: Bristol
country: United Kingdom
facility: Research Site
city: Bristol
country: United Kingdom
facility: Research Site
city: Edinburgh
country: United Kingdom
facility: Research Site
city: Harrow
country: United Kingdom
facility: Research Site
city: Hull
country: United Kingdom
facility: Research Site
city: London
country: United Kingdom
facility: Research Site
city: London
country: United Kingdom
facility: Research Site
city: London
country: United Kingdom
facility: Research Site
city: London
country: United Kingdom
facility: Research Site
city: Manchester
country: United Kingdom
facility: Research Site
city: Newcastle-upon-Tyne
country: United Kingdom
facility: Research Site
city: Nottingham
country: United Kingdom
facility: Research Site
city: Oxford
country: United Kingdom
facility: Research Site
city: Plymouth
country: United Kingdom
facility: Research Site
city: Portsmouth
country: United Kingdom
facility: Research Site
city: Sheffield
country: United Kingdom
facility: Research Site
city: Truro
country: United Kingdom
facility: Research Site
Study officials:
References: