Table 2.

Summary of developed circRNA vaccines.

Vaccine	Antigen	IRES	Cyclization Method	Delivery	Research Team	Period	Reference
circRNA RBD	Encodes SARS-CoV-2 RBD receptor binding domain	CVB3	Type I intron self-splicing	LNP	Therorna	March 2022	[30]
circRNA RBD	Encodes SARS-CoV-2 RBD receptor binding domain	CVB3	Type II intron self-splicing	LNP	Circode Bio	May 2022	[55]
VFLIP-X	Encodes SARS-CoV-2 spiking protein	CVB3	T4 RNA ligase	LNP	Patompon Wongtrakoongate et al. Mahidol University	March 2022	[94]
circRNAOVA-Luc	Encodes OVA (257–264) luciferase	CVB3	Type I intron self-splicing	LNP	Lin Xin et al. Tsinghua University School of Medicine	August 2022	[9]
CircRNA encoding cytokines	Encodes IL-15, IL-12, GM-CSF, IFN-α2b	EV29	Clean-PIE	LNP	CureMed	September 2022	[45]
IL12-circRNA	IL-12	CVB3	Type I intron self-splicing	LNP	B. Li, University Health Network Toronto	April 2024	[92]
cirA29L, cirA35R, cirB6R, and cirM1R	MPXV proteins A29L, A35R, B6R, and M1R	/	Type II intron self-splicing	LNP	Circode Bio	April 2024	[95]