COVID-19 vaccine effectiveness on variants of concern
(Randomized evidence)
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Gamma
Description of primary studies
| Trial | Type | Comparisons | Design | Participants | Sample size | Overall risk of bias Highest assessment |
Full description | |
|---|---|---|---|---|---|---|---|---|
| Intervention 1 | Intervention 2 | |||||||
|
Gamma Delta NCT04672395 Clover Biopharmaceuticals Inc./Dynavax Bravo L, Lancet, 2022 Full text Commentary Commentary |
Protein subunit |
SCB-2019 |
Placebo |
RCTPhase 2-3 | Healthy adults or with stable chronic conditions, both SARS-CoV-2 seropositive and seronegative, at 31 centers in Belgium, Brazil, Colombia, Philippines, and South Africa. | N=30174 |
Variant delta: Some concerns Details |
|
|
Beta Gamma Delta ChiCTR2100051998 Sinovac Research and Development Co. Ltd.; Anhui Zhifei Longcom Biopharmaceutical + Institute of Microbiology, Chinese Academy of Sciences Cao Y, Cell Res, 2021 Full text Commentary |
Inactivated virus |
CoronaVac/Boost ZF2001 |
CoronaVac/Boost CoronaVac |
RCTPhase 2 | Healthcare professionals with no previous confirmed COVID-19 at a single center in China who had received two doses of CoronaVac in a 28-day interval 4–8 months earlier | N=164 |
Some concerns Details |
|
|
Gamma ISRCTN89951424 AstraZeneca+University of Oxford Clemens S, Nat. Commun., 2021 Full text Commentary Commentary |
Non replicating viral vector |
ChAdOx1 |
MenACWY |
RCTPhase 3 | Adults that were SARS-CoV-2 seronegative and with no history of COVID-19 in six centers in Brazil. | N=10416 |
Variant gamma: Some concerns Details |
|
|
Beta Gamma Delta NCT05087368 Clover Biopharmaceuticals Inc./Dynavax ; AstraZeneca + University of Oxford Costa Clemens, Open Forum Infect. Dis., 2022 Full text Commentary Commentary Commentary Commentary |
Protein subunit |
ChAd/boost9mcgSCB-2019+al ChAd/B*9SCB-2019+al+CpG ChAd/B*30SCB-2019+al+CpG |
ChadOx1/boostChadOx1 |
RCTPhase 2 | Adults including healthy or stable co-morbidities with no history of SARS-CoV-2 infection who had previously received 2 doses of ChAdOx1-S1-S vaccine 6 months (±4 weeks) before enrollment in 3 centers in Brazil | N=120 |
Some concerns Details |
|
|
Alpha Gamma Delta NCT04646590 Anhui Zhifei Longcom Biopharmaceutical Dai L, N Engl J Med, 2022 Full text Commentary Commentary |
Protein subunit |
ZF2001 |
Placebo |
RCTPhase 3 | Adults 18 years of age or older with no history of Covid-19, positive tests for SARS-CoV-2 exposure or vaccination, or of congenital or acquired immune deficiency or autoimmune disease at 32 clinical centers across Uzbekistan, Indonesia, Pakistan, Ecuador and China. | N=28904 |
Variant delta: Some concerns Details |
|
|
Alpha Beta Gamma Delta NCT04636697 Medicago Inc Hager K, N Engl J Med, 2022 Full text Full text Commentary |
Virus-Like particle |
CoVLP |
Placebo |
RCTPhase 3 | Adults including elderly with and without comorbidities, with no previous history of virologically confirmed COVID-19, both seronegative and seropositive, at 85 centers in Argentina, Brazil, Canada, Mexico, the UK, and the USA. | N=24141 |
Variant delta: Some concerns Details |
|
|
Alpha Beta Gamma Delta NCT04614948 Janssen Pharmaceutical Companies Hardt K, Lancet Infect Dis, 2022 ENSEMBLE2 Full text Full text Commentary |
Non replicating viral vector |
Ad26.COV2.S Ad26.COV2.S |
Placebo |
RCTPhase 3 | Adults, healthy or with stable and well-controlled comorbidities, at 125 centers in Belgium, Brazil, Colombia, France, Germany, The Philippines, South Africa, Spain, UK, and USA | N=31835 |
Some concerns Details |
|
|
Alpha Gamma NCT04652102; EudraCT 2020-003998-22 CureVac AG Kremsner P, Lancet Infect Dis, 2022 HERALD Full text Commentary |
RNA based vaccine |
CVnCoV |
Placebo |
RCTPhase 2-3 | Adults with no history of COVID-19 in 47 centers in Belgium, Germany, The Netherlands, Spain, Argentina, Colombia, Dominican Republic, Mexico, Panama and Peru | N=39680 |
Some concerns Details |
|
|
Beta Gamma Delta NCT04611243 Sinovac/Pfizer/BioNTech+Fosun Pharma Mok C K P, Am. J. Respir. Crit., 2022 Full text Commentary |
RNA based vaccine |
CoronaVac/Boost |
CoronaVac/Boost BNT162b2 |
RCT* | Adults that had received two doses of CoronaVac but had low immune response against SARS-CoV-2 at two centres in Hong Kong, China | N=80 |
Some concerns Details |
|
|
Beta Gamma NCT04764422 The Government Pharmaceutical Organization (GPO); PATH; Dynavax Pitisuttithum P, medRxiv, 2021 Full text Commentary Commentary |
Inactivated virus |
NDV-HXP-S 1mcg NDV-HXP-S 1mcg + CpG1018 NDV-HXP-S 3mcg NDV-HXP-S 3mcg + CpG1018 NDV-HXP-S 10mcg NDV-HXP-S 1mcg |
Placebo |
RCTPhase 1 | Healthy adults without immunosuppression negative for SARS-CoV-2 antibodies at a single center in Thailand | N=210 |
Some concerns Details |
|
|
Alpha Beta Gamma Delta NCT05142319 Pfizer/BioNTech+Fosun Pharma; ModernaTX Poh XY, Clin. Infect. Dis., 2022 PRIBIVAC Full text Commentary |
RNA based vaccine |
BNT162b2/boostm1273 |
BNT162b2/boostBNT |
RCT3 | Adults at a single center in Singapore with no previous history of COVID-19 who had received a primary series of BTN162b2 at least 6 months previously | N=100 |
Some concerns Details |
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