Table 2.

Experimental design and developers of the included studies

Studies	Vaccines	Adjuvant	Research type	Phase	Developers	Registration ID
Voysey 2021[19]	Adenovirus recombinant vector vaccine (ChAdOx1 nCoV-19/AZD1222)	No	Randomized double /single blind control	I/II/III	AstraZeneca	NCT04324606, NCT04400838, NCT04444674
Polack 2020[20]	RNA vaccine (BNT162b2)	Lipid nanoparticle	Randomized single-blind control	II/III	BioNTech / Pfizer	NCT04368729
Xia 2020[21]	Inactivated vaccine	Aluminum hydroxide	Randomized double-blind control	I/II	Wuhan Institute of Biological Products Co. Ltd	ChiCTR2000031809
Pu 2020[22]	Inactivated vaccine	Aluminum hydroxide	Randomized double-blind control	I	Institute of Medical Biology, Chinese Academy of Medical Sciences	NCT04412538
Xia 2021[27]	Inactivated vaccine (BBIBP-CorV)	Aluminum hydroxide	Randomized double-blind control	I/II	Beijing Institute of Biological Products	ChiCTR2000032459
Che 2020[28]	Inactivated vaccine	Aluminum hydroxide	Randomized double-blind control	II	Institute of Medical Biology, Chinese Academy of Medical Sciences	NCT04412538
Ella 2020[29]	Inactivated vaccine (BBV152)	Algel-IMDGor Algel	Randomized double-blind control	I	Bharat Biotech	NCT04471519
Keech 2020[30]	Recombinant spiroprotein nanoparticle vaccine (NVX-CoV2373)	Mareix-m1	Randomized double-blind control	II	Novavax	NCT04368988
Mulligan 2020[31]	RNA vaccine (BNT162b1)	Lipid nanoparticle	Randomized double-blind control	I/II	BioNTech/Pfizer	NCT04368728
Richmond 2020[32]	Recombinant spiroprotein vaccine (SCB-2019)	ASO3 or CpG/Alum	Randomized double-blind control	I	Clover Biopharmaceuticals	NCT04405908
Walsh 2020[33]	RNA vaccine (BNT162b1/ BNT162b2)	Lipid nanoparticle	Randomized single-blind control	I	BioNTech/ Pfizer	NCT04368728
Zhang 2021[34]	Inactivated vaccine	Aluminum hydroxide	Randomized double-blind control	I/II	SINOVAC BIOTECH CO.LTD.	NCT04352608
Zhu 2020[35]	Adenovirus type-5-vectored vaccine	No	Randomized double-blind control	II	Beijing Institute of Biotechnology and Citic Biological	NCT04341389