Table 2. Formulation aspects of some of the approved vaccine for COVID-19.
| Vaccines | Active ingredients | Excipients | Efficacy | Dose and route of administration | Storage | Ref. |
|---|---|---|---|---|---|---|
| Pfizer (BNT162b2) | Modified mRNA | • (4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis (ALC-3015) • (2-hexyldecanoate),2-[(polyethylene glycol)-2000]-N,N-ditetradecylacetamide (ALC-0159) • 1,2-distearoyl-snglycero-3-phosphocholine (DPSC) Cholesterol • KCl • KH2PO4 • NaCl • NaH2PO4 · 2H2O • Sucrose |
95% | 2 doses, 3 weeks apart, muscle injection | Freezer storage only at -70°C | [138,139] |
| Moderna (mRNA-1273) | Modified mRNA | • SM-102 • 1,2-dimyristoyl-rac-glycero3-methoxypolyethylene glycol-2000 (PEG2000-DMG) • DSPC Cholesterol • Tris buffer • TRIS hydrochloride • CH3COOH • CH3COONa • Sucrose |
94.5 % | 2 doses, 4 weeks apart, muscle injection | 30 days with refrigeration, 6 months at -20°C | [137,140] |
| Bharat Biotech (Covaxin) | Whole-virion inactivated SARS-CoV-2 antigen | • Aluminum hydroxide gel • Imidazoquinolinone • 2-phenoxyethanol • Phosphate buffer saline |
78% | 2 doses given 4 weeks apart, muscle injection | At least a week at room temperature | [141] |
| Covishield (Serum Institute of India Ltd) | ChAdOx1 nCoV-19 corona virus vaccine (Recombinant) | • L-Histidine • L-Histidine hydrochloride monohydrate • Magnesium chloride hexahydrate • Polysorbate 80 • Ethanol • Sucrose • Sodium chloride • Disodium edetate dihydrate (EDTA) • Water for injection |
76% | 2 doses given 4 weeks apart, muscle injection | Stable in the refrigerator for at least 6 months | [142] |
| Sputnik V | Adenovirus viral vector vaccine | • Tris (hydroxymethyl) aminomethane • NaCl • Sucrose • Magnesium chloride hexahydrate • EDTA sodium salt dihydrate • Polysorbate 80 • Ethanol 95% • Water for injection |
91.6% | 2 doses given 3 weeks apart, muscle injection | Freezer storage | [143,144] |
| Janssen Ad26.COV2.S vaccine | Viral vector Ad26.COV2 | • Citric acid monohydrate • Trisodium citrate dihydrate • Ethanol • 2-hydroxypropyl-beta-cyclodextrin (HBCD) • Polysorbate 80 • NaCl • NaOH • HCl |
72% | Single dose, muscle injection | Up to two years frozen at -4°F (-20°C), and up to 4.5 months refrigerated at 36–46°F (2–8°C). | [145] |
In the Pfizer and Moderna vaccine, lipids used for the development of liposomal vaccine carrier that can encapsulate and protect mRNA from degradation. Salts act as a buffer that maintain the pH level close to the pH of the physiological system. Sucrose acts as a cryoprotectant for safeguarding liposomes during freezing.
In Covaxin, imidazoquinolinone has been used as Toll-like receptor-7/8 agonist.