Table 1 Characteristics of the clinical studies included in the network meta-analysis

Inactivated vaccine

Ella, 2021

NCT04641481

BBV152

III

Double-blind RCT

India

Nov 16, 2020-Jan 7, 2021

2

28

6 µg

8471/8502

40.1

67.1

Kaabi, 2021

NCT04510207

WIBP-CorV (WIV04)

III

Double-blind RCT

The United Arab Emirates, Bahrain

Jul 16, 2020-Dec 31, 2020

2

21

5 µg

12,743/12,737

36.1

84.4

Kaabi, 2021

NCT04510207

BBIBP-CorV (HB02)

III

Double-blind RCT

The United Arab Emirates, Bahrain

Jul 16, 2020-Dec 31, 2020

2

21

4 µg

12,726/12,737

-

84.4

Tanriover, 2021

NCT04582344

CoronaVac

III

Double-blind RCT

Turkey

Sept 14, 2020-Mar 16, 2021

2

14

3 µg

6559/3470

-

57.8

Palacios, 2021

NCT04456595

CoronaVac

III

Double-blind RCT

Brazil

Jul 21, 2020-Dec 16, 2020

2

14

3 µg

4953/4870

39.5

35.8

Fadlyana,2021

NCT04508075

CoronaVac

III

Observer-blinded RCT

Indonesia

Aug 11, 2020-Oct 21, 2020

2

14

3 µg

798/804

35.5

64.6

Khairullin, 2022 NCT04691908

QazCovid-in

III

Single-blind RCT

Kazakhstan

Dec 25, 2020- Jul 11, 2021

2

21

5 mg

2400/600

-

51

Mohraz, 2023

IRCT20201202049567N3

BIV1-CovIran

III

Double-blind RCT

Iran

May 16, 2021-Jul 15, 2021

2

28

5 µg

13,335/6665

38.3

65.4

mRNA vaccine

Sahly, 2021

NCT04470427

mRNA-1273

III

Observer-blinded RCT

US

Jul 27, 2020-Oct 23, 2020

2

28

100 µg

14,287/14,164

51.4

52.6

Polack, 2020

NCT04368728

BNT162b2

III

Observer-blinded RCT

US, Argentina, Brazil

Jul 27, 2020-Nov 14, 2020

2

21

30 µg

17,411/17,511

-

50.6

Kremsner, 2022

NCT04652102

CVnCoV

III

Observer-blinded RCT

Europe, Latin America

Dec 11, 2020-Apr 12, 2021

2

28

12 µg

12,851/12,211

43

54.9

DNA vaccine

Khobragade, 2022 CTRI/2021/01/030416

ZyCoV-D

III

Double-blind RCT

India

Jan 16, 2021-Jun 23, 2021

3

28

2 mg

12,350/12,320

36.5

67.11

Viral vector vaccine

Logunov, 2021

NCT04530396

Gam-COVID-Vac (Sputnik V)

III

Double-blind RCT

Russia

Sept 7, 2020-Nov 24, 2020

2

21

10¹¹

14,964/4902

45.3

55.1

Sadoff, 2022

NCT04505722

Ad26.COV2.S

III

Double-blind RCT

Argentina, Brazil, Chile, Colombia, Mexico, Peru, South Africa, US

Sept 21, 2020-Jul 9, 2021

1

N/A

5 × 10¹¹⁰

19,514/19,544

-

54.9

Voysey, 2021

NCT04324606

NCT04400838

NCT04536051

NCT04444674

AZD1222 (ChAdOx1 nCoV-19)

I/II

Single-blind RCT

UK, cov001

Apr 23, 2020-Nov 6, 2020

2

28–84

3·5–6·5 × 10¹¹⁰

7201/7179

-

39.5

II/III

UK, cov002

III

Brazil, cov003

I/II

Double-blind RCT

South Africa, cov005

Falsey, 2021

NCT04516746

AZD1222 (ChAdOx1 nCoV-19)

III

Double-blind RCT

US, Chile, Peru

Aug 28, 2020-Jan 15, 2021

2

14

5 × 10¹¹⁰

17,662/8550

50.2

55.6

Halperin, 2022

NCT04526990

Ad5-nCoV

III

Double-blind RCT

Argentina, Chile, Mexico, Pakistan, Russia

Sept 22, 2020-Jan 15, 2021

1

N/A

5 × 10¹¹⁰

14,591/14,586

37.8

70.8

Protein subunit vaccine

Heath, 2021

2020-004123-16

NVX-CoV2373

III

Observer-blinded RCT

UK

Sept 28, 2020- Nov 28, 2020

2

21

5 µg

7020/7019

-

51.6

Dunkle, 2022

NCT04611802

NVX-CoV2373

III

Observer-blinded RCT

US, Mexico

Dec 27, 2020- Feb 18, 2021

2

21

5 µg

17,312/8140

-

51.8

Bravo, 2022

NCT04672395

SCB-2019

II/III

Double-blind RCT

Belgium, Brazil, Colombia, Philippines, South Africa

Mar 24, 2021-Aug 10, 2021

2

21

30 µg

6251/6104

31.1

55

Dai, 2022

NCT04646590

ZF2001

III

Double-blind RCT

Uzbekistan, Indonesia, Pakistan, Ecuador, China

Dec 12, 2020-Dec 15, 2021

3

30

25 µg

12,625/12,568

36.8

67.5

Tabarsi, 2022

NCT05005559

SpikoGen

III

Double-blind RCT

Iran

Aug 7, 2021-Nov 2021

2

21

25 µg

12,657/4219

33.1

56.6

Bernal, 2023

RPCEC00000359

Abdala

III

Double-blind RCT

Cuba

Mar 22, 2021-Jun 2021

3

14

50 µg

24,146/24,144

48.9

47.6

Ryzhikov, 2023

NCT04780035

EpiVacCorona

III

Double-blind RCT

Russia

Nov 27, 2020-Aug 31, 2021

2

21

225 ± 45 µg

2253/746

48.4

51.9

Mostafavi, 2023

IFV/COR/09

Soberana

III

Double-blind RCT

Iran

Apr 26, 2021-Sep 25, 2021

3

28

25–50µg

4340/1081

39.7

59.8

Hager, 2022

NCT04636697

CoVLP + AS03

III

Double-blind RCT

Argentina, Brazil, Canada, Mexico, UK, US

Mar 15, 2021-Sept 2, 2021

2

21

3.75 µg

12,074/12,067

32.8

50.9