Alternative Methods of Vaccine Delivery: An Overview of Edible and Intradermal Vaccines

Table 1

Status of development of plant-based vaccines.

Pathogen	Antigen	Plant host	Expression system	Indication	Route of administration	Clinical trial status	Clinical trial ID	Refs
Enterotoxigenic E. coli	LT-B	Potato	Transgenic	Diarrhea	Edible	Early phase 1	▶	[42]
Enterotoxigenic E. coli	LT-B	Maize	Transgenic	Diarrhea	Edible	Early phase 1	▶	[43]
Norwalk virus	CP	Potato	Transgenic	Diarrhea	Edible	Early phase 1	▶	[44]
Rabies virus	GP/NP (fusion)	Spinach	Viral vector (transient)	Rabies	Edible	Early phase 1	▶	[45]
HBV	HBsAg	Lettuce	Transgenic	Hepatitis B	Edible	Early phase 1	▶	[46]
HBV	HBsAg	Potato	Transgenic	Hepatitis B	Edible	Phase 1	NCT01292421	[47]
Vibrio cholerae	CTB	Rice	Transgenic	Cholera	Edible	Phase 1	UMIN000009688	[48–51]

HBsAg: hepatitis B surface antigen; CP: capsid protein; GP: glycoprotein; NP: nucleoprotein; CTB: cholera toxin subunit B. ▶: restricted cohort study design.