Covid-19 living Data

COVID-19 vaccine effectiveness on variants of concern
(Randomized evidence)

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Delta

Forest plots
(last update: 2022-04-15)

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	RCT Phase 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	Full description
Delta NCT04796896 ModernaTX Creech CB, N Engl J Med, 2022 KidCOVE Full text Commentary	RNA based vaccine	mRNA-1273 (50 mcg)	Placebo	RCT Phase 2-3	Children aged 6-11 years, healthy or with stable chronic conditions and no known recent history of COVID-19 infection, at 87 centers in Canada and USA.	N=4016	Variant delta: Some concerns Details	Full description
Alpha Gamma Delta NCT04646590 Anhui Zhifei Longcom Biopharmaceutical Dai L, N Engl J Med, 2022 Full text Commentary Commentary	Protein subunit	ZF2001	Placebo	RCT Phase 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	Full description
Alpha Delta NCT04641481 Bharat Biotech Ella R, Lancet, 2021 Full text Commentary	Inactivated virus	BBV152	Adjuvant	RCT Phase 3	Adults with no history of SARS-CoV-2 infection who were healthy or had stable chronic medical conditions at 25 centers in India	N=25798	Variant delta: Some concerns Details Variant alpha: Some concerns Details	Full description
Alpha Beta Gamma Delta NCT04636697 Medicago Inc Hager K, N Engl J Med, 2022 Full text Full text Commentary	Virus-Like particle	CoVLP	Placebo	RCT Phase 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	Full description
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	RCT Phase 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	Full description
Alpha Beta Delta NCT04649021 Pfizer/BioNTech+Fosun Pharma Hui A-M, Lancet, 2022 Full text Full text Commentary Commentary	RNA based vaccine	BNT162b2	Placebo	RCT Phase 2	Healthy adults and those with a pre-existing stable condition, at 2 centers in China.	N=960	Low Details	Full description
Alpha Beta Delta NCT04900467; EudraCT: 2021-002174-52 Moderna;Pfizer/BioNTech Janssen C, EClinicalMedicine, 2022 Full text Full text Commentary	Heterologous vaccination scheme	BNT/mRNA-1273 m1273/BNT162b2	BNT162b2 mRNA-1273	RCT Phase 2	Adults with no known or suspected history of SARS-CoV-2 infection at 17 centers in France.	N=414	Some concerns Details	Full description
Delta CTRI/2021/01/030416 Zydus Cadila Khobragade A, Lancet , 2022 Full text Commentary	DNA based vaccine	ZyCoV-D	Placebo	RCT Phase 3	Healthy adults and adolescents aged (≥12 years) with no previous history of COVID-19 at 49 centers in India.	N=27703	Variant delta: Some concerns Details	Full description
Beta Delta NCT04444674 AstraZeneca + University of Oxford Koen A, medRxiv, 2022 COV005 Full text Full text Commentary	Non replicating viral vector	ChAdOx1	Placebo	RCT Phase 1-2	Healthy adults aged 18–65 years in 7 centres in South Africa	N=2130	Variant beta: Some concerns Details	Full description
Beta Delta NCT04762680 Sanofi Pasteur+GlaxoSmithKline Sridhar S, Lancet Infect Dis , 2022 Full text Commentary	Protein subunit	CoV2 preS dTM 15 mcg CoV2 preS dTM 10 mcg	CoV2 preS dTM 5 mcg	RCT Phase 2	Adults with and without prior SARS-CoV-2 infection and risk factors for severe disease at 20 centers in the USA and Honduras	N=722	Some concerns Details	Full description
Beta Delta ISRCTN27841311; EudraCT 2021-001275-16 Pfizer BioNTech + Fosun Pharma / Novavax / Moderna + NIAID Stuart A, Lancet, 2021 Com-COV2 Full text Commentary Commentary	Protein subunit	BNT/NVX-CoV2373 BNT/mRNA-1273	BNT162b2	RCT Phase 2	Adults over 50 years previously vaccinated with one dose of BNT162b2 at 9 centres in the UK	N=532	Some concerns Details	Full description
Beta Delta ISRCTN27841311; EudraCT 2021-001275-16 AstraZeneca + University of Oxford / Novavax / Moderna + NIAID Stuart A, Lancet, 2021 Com-COV2 Full text Commentary Commentary	Protein subunit	ChAd/NVX-CoV2373 ChAd/mRNA-1273	ChAdOx1	RCT Phase 2	Healthy adults over 50 years previously vaccinated with one dose of ChAdOx1 nCoV-19 in 9 centres in the UK	N=540	Some concerns Details	Full description
Delta CTRI/2021/08/036074 Biological E;AstraZeneca+University of Oxford Thuluva , medRxiv, 2022 Full text Commentary Commentary	Protein subunit	BECOV2	ChAdOx1	RCT Phase 3	Healthy adults without a history of Covid-19 vaccination or SARS-CoV-2 infection at 20 centers in India.	N=2140	Some concerns Details	Full description
Delta CTRI/2021/10/037066 Biological E. Limited Thuluva S, Vaccine, 2022 Full text Full text Commentary Commentary Commentary	Protein subunit	BECOV2 ≥5 to <12 BECOV2 ≥12 to <18	Placebo	RCT Phase 2-3	Healthy children and adolescents who were SARS-CoV-2 RT-PCR and anti-SARS-CoV-2 antibody negative in 23 centers in India	N=390	Low Details	Full description
Beta Delta RPCEC00000354 Instituto Finlay de Vacunas Toledo-Romani ME, medRxiv, 2022 Full text Full text Commentary	Protein subunit	FINLAY-FR-2	Placebo	RCT Phase 3	Adults in medically stable condition with no self-reported previous COVID-19 infection at 48 centers in Cuba	N=29352	Some concerns Details	Full description
Alpha Beta Delta RPCEC00000347 Instituto Finlay de Vacunas Toledo-Romani ME, Med, 2022 Full text Commentary Commentary Commentary	Protein subunit	SOBERANA 02/SOBERANA plus	Adjuvant	RCT Phase 2b	Healthy adults with no known or suspected history of COVID-19 at 2 centers in Cuba.	N=810	Some concerns Details	Full description
Delta NCT04816643 Pfizer/BioNTech+Fosun Pharma Walter E, N Engl J Med, 2021 Full text Commentary	RNA based vaccine	BNT162b2 10 mcg	Placebo	RCT Phase 2-3	Children aged 5-11 years with or without stable co-morbidities with no history of COVID-19 in 81 centres in the USA, Spain, Finland, and Poland	N=2285	Variant delta: Some concerns Details	Full description