COVID-19 vaccine effectiveness
(Randomized evidence)
Analyses are updated every Friday
Variants of concern
Vaccine types
Overall results (Last update:2021-10-22)
- Forest plots (last update: 2021-10-21)
- Studies included
- Forest plots (last update: 2021-10-15)
- Studies included
- Forest plots (last update: 2021-10-21)
- Studies included
- Forest plots (last update: 2021-10-21)
- Studies included
- BNT/ChA-28 vs BNT/BNT-28 - Forest plots (last update: 2021-08-11)
- BNT162b2 primed with ChAdOx1-S vs No vaccine - Forest plots (last update: 2021-08-11)
- ChAd/BNT-28 vs ChAd/ChAd-28 - Forest plots (last update: 2021-08-11)
RNA based vaccine
Non replicating viral vector
Inactivated virus
Protein subunit
Heterologous
| Trial | Type | Comparisons | Design | Participants | Sample size | Overall risk of bias Highest assessment |
Full description | |
|---|---|---|---|---|---|---|---|---|
| Intervention 1 | Intervention 2 | |||||||
|
EudraCT 2021-002348-57 Pfizer–BioNTech; Moderna; Oxford-AstraZeneca Bonelli M, medRxiv, 2021 Full text Commentary Commentary |
Non replicating viral vector |
ChAdOx1 booster |
BNT or mRNA booster |
RCT* | Adults under current rituximab therapy who did not develop humoral response against SARS-CoV-2 after their standard vaccination with Biontech/Pfizer or Moderna in a single center in Austria | N=60 |
Some concerns Details |
|
|
NCT04400838 AstraZeneca + University of Oxford Emary K, Lancet, 2021 Full text Commentary |
Non replicating viral vector |
ChAdOx1 |
MenACWY |
RCTPhase 2-3 | Adults seronegative at baseline enrolled at 19 study sites in UK | N=10673 |
Some concerns Details |
|
|
NCT04516746 AstraZeneca + University of Oxford Falsey A, N Engl J Med, 2021 Full text Commentary |
Non replicating viral vector |
ChAdOx1 |
Placebo |
RCTPhase 3 | Adults (22% over 65 years) at high risk for exposure to SARS-CoV-2 and populations at increased risk for Covid-19 complications at 88 sites in USA, Chile, and Peru | N=32451 |
Some concerns Details |
|
|
NCT04324606; ISRCTN15281137 AstraZeneca + University of Oxford Folegatti PM, Lancet, 2020 COV001 Full text Commentary ; Commentary (20)31611-1/fulltext |
Non replicating viral vector |
ChAdOx1 SD |
MenACWY |
RCTPhase 1 - 2 | Healthy adults with no history of laboratory confirmed SARS-CoV-2 infection or of COVID-19-like symptoms in five centres in the UK | N=1067 |
Low Details |
|
|
CTRI/2020/08/027170 AstraZeneca + University of Oxford / Serum Institute of India Kulkarni P, SSRN, 2021 Full text Commentary Commentary |
Non replicating viral vector |
SII-ChAdOx1 |
Placebo |
RCTPhase 2-3 | Adults (seronegative and seropositive)without a history of COVID and not immunocompromised at 14 centers in India | N=1200 |
Some concerns Details |
|
|
CTRI/2020/08/027170 Serum Institute of India / AstraZeneca/Oxford University Kulkarni P, SSRN, 2021 Full text Commentary Commentary |
Non replicating viral vector |
SII-ChAdOx1 |
ChAdOx1 |
RCTPhase 2-3 | Adults (seronegative and seropositive) without a history of COVID and not immunocompromised at 14 centers in India | N=401 |
Some concerns Details |
|
|
ISRCTN69254139, EudraCT: 2020-005085-33 AstraZeneca+University of Oxford; Pfizer/BioNTech+Fosun Pharma Liu X, Lancet, 2021 Com-COV Full text Commentary |
RNA based vaccine |
ChAd/BNT BNT/ChAd |
ChAd/ChAd BNT/BNT |
RCTPhase 2 | Adults 50 years or older with no previous SARS-CoV-2 infection, no or well-controlled mild-moderate comorbidities and HIV-negative in 8 centers in the UK | N=463 |
Some concerns Details |
|
|
NCT04530396 Gamaleya Research Institute of Epidemiology and Microbiology Logunov D, Lancet, 2021 RESIST Full text Commentary ; Commentary ; Commentary |
Non replicating viral vector |
GAM-COVID-VAC |
Placebo |
RCTPhase 3 | SARS-CoV-2- and HIV infection-free adult volunteers at 25 centers in Russia | N=21977 |
Some concerns Details |
|
|
NCT04444674 AstraZeneca + University of Oxford Madhi S, N Engl J Med, 2021 COV005 Full text Commentary |
Non replicating viral vector |
ChAdOx1 |
Placebo |
RCTPhase 1-2 | Healthy adult volunteers that were HIV-negative and SARS-CoV-2 infection-free in 7 centres in South Africa | N=2026 |
Some concerns Details |
|
|
NCT04444674, PACTR202006922165132 AstraZeneca + University of Oxford Madhi S, Lancet, 2021 Full text Commentary |
Non replicating viral vector |
ChAdOx1 |
Placebo |
RCTPhase 1-2 | Adults living with HIV in 7 centers in South Africa | N=104 |
Low Details |
|
|
NCT04505722 Janssen Pharmaceutical Companies Sadoff J, N Engl J Med, 2021 ENSEMBLE Full text Commentary |
Non replicating viral vector |
Ad26.COV2.S |
Placebo |
RCTPhase 3 | Adults >18 years of age at 213 centers in Argentina, Brazil, Chile, Colombia, Mexico, Peru, South Africa and USA | N=44325 |
Some concerns Details |
|
|
NCT04436276 Janssen Pharmaceutical Companies Sadoff J, N Engl J Med, 2021 ENSEMBLE Full text Commentary |
Non replicating viral vector |
Ad26.COV2.S Ad26.COV2.S 1x10^11vp |
Placebo |
RCTPhase 1-2 | Healthy SARS-CoV-2 nucleic acid negative adults 18-55 years old and elderly >65 years old in multiple centres in Belgium and the US | N=810 |
Some concerns Details |
|
|
ISRCTN89951424 AstraZeneca + University of Oxford Voysey M, Lancet, 2020 COV003 Full text Commentary |
Non replicating viral vector |
ChAdOx1 |
Placebo |
RCTPhase 3 | Healthy SARS-CoV-2 serology/DNA negative adults in six centres in Brazil | N=10002 |
Some concerns Details |
|
|
NCT04324606; ISRCTN89951424 ;NCT04400838;NCT044446 AstraZeneca + University of Oxford Voysey M, Lancet, 2021 COV001/COV002/COV003/COV005 Full text Commentary ; Commentary ; Commentary |
Non replicating viral vector |
ChAdOx1 |
Placebo |
RCTphase 1/2/3 | Adults seronegative at baseline from four studies in multiple centres in Brazil, South Africa, and the UK | N=24422 |
Some concerns Details |
|
|
NCT04400838 AstraZeneca + University of Oxford Voysey M, Lancet, 2020 COV002 Full text Commentary |
Non replicating viral vector |
ChAdOx1 LD/SD ChAdOx1 SD/SD |
Placebo |
RCTPhase 2/3 | Healthy adults in 18 centres in the UK | N=10673 |
Some concerns Details |
|
|
NCT04552366 Beijing Institute of Biotechnology, Beijing, China, and CanSino Biologics Wu S, Lancet, 2021 Full text Commentary |
Non replicating viral vector |
Ad5-nCoV 2×10¹⁰ vp mu D0 Ad5-nCoV 2×10¹⁰ vp mu D0 Ad5-nCoV 2×10¹⁰ vp mu D0 Ad5-nCoV 2×10¹⁰ vp mu D0 |
Ad5-nCoV 1×10¹⁰ vp mu D0 Ad5-nCoV 5×10¹⁰ vp im D0 Ad5-nCoV 5×10¹⁰ vp im D0 Ad5-nCoV 10×10¹⁰ vp im D0 |
RCTPhase 1 | Adults who were HIV-negative and seronegative for SARS-CoV-2 at a single center in China | N=130 |
Some concerns Details |
|
|
NCT04341389 CanSino Biological Inc./Beijing Institute of Biotechnology Zhu F, Lancet, 2020 Full text Commentary Commentary |
Non replicating viral vector |
Ad5-vectored 1×10¹¹ vp Ad5-vectored 1×10¹¹ vp Ad5-vectored 5×10¹⁰ vp |
Ad5-vectored 5×10¹⁰ vp Placebo Placebo |
RCTPhase 2 | Healthy adult volunteers with HIV-negative and SARS-CoV-2 infection-free in a single centre in China. | N=508 |
Some concerns Details |
|