Table Info

Table 1.

COVID-19 vaccine types available for current preclinical/clinical application and their manufactures

No.	Vaccine types	Mechanism of vaccine development	Manufacturer
1	Inactivated	SARS-CoV-2 grown in cell culture	Sinopharm + China National Biotec Group, Co + Wuhan Institute of Biological Products, COVAXIN (Bharat Biotech International Limited)
		Chemical inactivation of the virus
		Combined with alum or another adjuvant
2	Live attenuated	Genetically weakened SARS-CoV-2	-
		SARS-CoV-2 grown in adverse conditions
		Virulence is lost with maintained immunogenicity
3	Recombinant virus vector	Viral proteins (RBP, S protein) expressed on mammalian cells, yeasts, or plants	NVX-CoV2373 (Novavax)
4	Virus vector	Genetically engineered vaccines	-
4	Virus vector	Use vectors uncommon to cause human infections, e.g., chimpanzee adenovirus	-
4.1	Replication incompetent vector	Engineered, to not replicate in vivo and express the viral protein	Ad26.COV2.S (Janssen/Johnson & Johnson)
			ChAdOx1 nCoV-19/AZD1222 (AstraZeneca/
			University of Oxford/Serum Institute of India)
			Gam-COVID-Vac (Sputnik V) (Gamaleya Institute)
4.2	Replication competent vector	Engineered to express the spike protein and replicate within the vaccinated individual	-
5	Nucleic acid vaccines	Exogenous nucleic acid is detected by innate immune receptors which generate robust immune response	-
	DNA	Plasmid DNA with mammalian expression promotors and the target gene	Zydus Cadila (ZyCoV-D) [102]

RBP: receptor binding protein; -: not applicable/not available

Declarations

Author contributions

MG and MM: conception, drafting, organizing, revision, and final approval of the manuscript; SG, VS and IPS: drafting, organizing, revision, and final approval of the manuscript; HB: illustrations, drafting, revision, and final approval of the manuscript; YK: drafting, organizing, revision, and final approval of the manuscript.

Conflicts of interest

The authors declare that they have no conflicts of interest.

Ethical approval

Not applicable.

Consent to participate

Not applicable.

Consent to publication

Not applicable.

Availability of data and materials

Not applicable.

Funding

Not applicable.

Copyright

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