Table 3.
List of vaccine candidates against SARS-CoV/CoV-2 produced in plants (As of 13 August 2021).
| Vaccine Antigen | Plant Host | Formulation and Route | Immunogenicity | Status | Reference |
|---|---|---|---|---|---|
| SARS-CoV S1 protein | Stable expression in tomato |
GI with 2-week intervals for 3 doses | Significantly increased titers of SARS-CoV-specific antibodies after immunization in mice | Pre-clinical study | [106] |
| SARS-CoV nucleocapsid protein | Transient expression in N. benthamiana |
Formulated with Freund’s adjuvant and IP with at 2-week intervals for four doses | Able to induce humoral immunity as well as SARS-CoV-2 cytokine-producing cells in mice | Pre-clinical study | [107] |
| SARS-CoV S1-GFP fusion protein | Transient expression in N. benthamiana |
N/A | N/A | Research | [112] |
| Recombinant SARS-CoV N and M protein | Transient expression in N. benthamiana |
N/A | N/A | Research | [113] |
| Recombinant SARS-CoV-2 N protein | Transient expression in N. benthamiana |
N/A | N/A | Research | [114] |
| Recombinant SARS-CoV-2 RBD protein | Transient expression in N. benthamiana |
N/A | N/A | Research | [114] |
| KBP-201 COVID-19 vaccine: SARS-CoV-2 RBD-based vaccine developed by Kentucky BioProcessing, Inc. (Owensboro, KY, USA) | Transient expression in N. benthamiana |
Formulated with CpG adjuvant and IM injection on day 1 and 22 | Able to induce positive SARS-CoV-2-specific immunity in pre-clinical trials | Phase I/II ClinicalTrials.gov Identifier: NCT04473690 |
[115] |
| IBIO-200 vaccine: SARS-CoV-2 VLP-based vaccine developed by iBio, Inc. (Bryan, TX, USA) | Transient expression in N. benthamiana |
IM injection on day 1 and 21 | Able to stimulate specific immune responses and neutralizing antibody against SARS-CoV-2 in mice | Pre-clinical study | [116] |
| IBIO-201 vaccine: SARS-CoV-2 Spike-based sub-unit vaccine developed by iBio, Inc. (Bryan, TX, USA) | Transient expression in N. benthamiana |
Formulated with LicKMTM adjuvant and IM injection on day 1 and 21 | Able to stimulate specific immune responses and neutralizing activities against SARS-CoV-2 in mice more than IBIO-200 | Pre-clinical study | [116] |
| IBIO-202 vaccine: SARS-CoV-2 nucleocapsid protein-based sub-unit vaccine developed by iBio, Inc. (Bryan, TX, USA) | Transient expression in N. benthamiana |
N/A | Able to induce robust, antigen-specific, memory T cell response | Pre-clinical study | [117] |
| SARS-CoV-2 VLP-based vaccine developed by Medicago Inc. (Quebec City, QC, Canada, Canada) |
Transient expression in N. benthamiana |
IM injection given 21 days apart | Able to induce antibody responses in the volunteers with two doses of immunization | Phase II/III ClinicalTrials.gov Identifier: NCT04636697 |
[118] |
| Baiya SARS-CoV-2 Vax 1 subunit vaccine developed by Baiya Phytopharm Co., Ltd. (Bangkok, Thailand) | Transient expression in N. benthamiana |
Formulated with alum adjuvant and IM injection on day 1 and 21 | Able to induce antigen-specific IgG and neutralizing responses as well as cellular immunity in mice and non-human primates | Pre-clinical study | [58] |
N/A: not available; GI: gastric intubation; IM: intramuscular immunization.