Table 1.
Summary of SARS-CoV-2 vaccine strategies with their advantages and limitations.
| S. No. | Strategies | Advantages | Limitations | Leading Candidates |
|---|---|---|---|---|
| 1 | DNA vaccine | Stable, cost effective, induces cellular, humoral and neutralizing antibody response |
Immunogenicity lower than viral vaccines | Zycov-D, INO-4800 |
| 2 | mRNA vaccine | Easy to design, lower risk of accidental infection than viral vaccines | Carrier required to stabilize and pack naked RNA | BNT162b2, mRNA-1273, ARCoV, CureVac (Tübingen, Germany) |
| 3 | Protein subunit vaccine |
Non-infectious, pure antigens easily elicit immunogenic response | Comparatively costlier | Corbevax, Sanofi (Paris, France) NVX-CoV2373, UB612, SCB-2019, EpiVacCorona (Federal Budgetary Research Institution State Research Center of Virology and Biotechnology, Koltsovo, Russia), Nanocovax (Nanogen Pharmaceutical, Ho Chi Minh City, Vietnam) |
| 4 | Recombinant viral vector vaccine | Efficient design easily elicits immunogenicity to desired level, fast and reusable platform |
Possibility of undesirable reactions, possibility of Th2 bias | AZD1222, Janssen (Bersee, Belgium), Immunity Bio (Culver City, CA, USA), GRAd-COV2, Sputnik V (Gamaleya Research Institute, Moscow, Russia), Convidicea (Cansino Biologics, Tianjin, China), OraPro-COVID-19™ (IosBio, Somarset, UK and Biocell Corporation, Auckland, New Zealand) |
| 5 | Live attenuated vaccine |
Presents entire viral antigen to immune system, strong and long-lasting immune response | Risk of infection going out of control, not suitable for immunocompromised individuals |
Covi-Vac, BCG (repurposing) |
| 6 | Whole killed vaccine | Rapid development, can elicit very good immunogenic response, broad antigenic profile | Th2 bias | BBIBP-CorV, CoronaVac, VLA2001, BBV152 |
| 7 | Virus like particles vaccine | Non-infectious, broad antigenic profile | Weaker immunogenicity | Medicago (Quebec City, Canada) |