Table 3.
Comparative table of clinical studies with Adenoviral vector-based COVID-19 vaccine candidates.
| Developer | Name of Candidate Vaccine | Most Advanced Stage of Clinical Trial | Location of development | NCT Number of Corresponding Clinical Trial | Route of administration | Dose groups (viral particles) | Participants | RBD-specific ELISA Abs [AU]/mL | GMT of NAbs [AU]/mL | Interferon γ Responses (%) | Grade 1/2 adverse reactions (%) | Severe adverse reactions (grade 3) (%) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CanSino Biologics Inc. and Beijing Institute of Biotechnology | Ad5-nCOV | Phase 3 | China | Phase 2 NCT04341389 | Intramuscular Single dose | 1 × 1011 | 253 | 656.5 | 19.5 | 90 | 73 | 9 |
| 5 × 1010 | 129 | 571.0 (Day 28) | 18.3 (Day 28) | 88 | 74 | 1 | ||||||
| Placebo | 126 | - | - | - | - | - | ||||||
| ImmunityBio, Inc. and NantKwest Inc. | hAd5-S-Fusion+N-ETSD | Phase 1 | USA | Phase 1b NCT04341389 | Sublingual on Day 1 and 22 | 1 × 1011 or 5 × 1010 | 35 | NA | NA | NA | NA | NA |
| Vaxart | VXA-COV2-1 | Phase 1 | USA | Phase 1 NCT04563702 | Oral tablet on Day 1 | 1 × 1010 or 1 × 1011 | 35 | NA | NA | NA | NA | NA |
| Altimmune, Inc. | AdCOVID | Phase 1 | USA | Phase 1 NCT04679909 | Intranasal spray, single or two doses | Low, Medium, or High | 180 | NA | NA | NA | NA | NA |
| Janssen Vaccines & Prevention B.V. (Johnson & Johnson) | Ad26.COV2-S | Phase 3 | Netherlands | Phase1/2a NCT04436276 | Intramuscular Single or two doses | 1 × 1011 | 1045 | 478–586 | 224–354 (Day 29) | 64 | 84 | 20 |
| 5 × 1010 | 625–788 (Day 29) | 827–1266 (after 2 doses) | 51 | 65 | 9 | |||||||
| Placebo | – | – | – | 23–26 | 0 | |||||||
| Gamaleya Research Institute | Gam-COVID-Vac/ SputnikV | Phase 3 | Russia | Phase 3 NCT04530396 | Intramuscular Prime (rAd26-s)-boost (rAd5-S) on Day 0 and Day 21 | 1 × 1011 | 21977 | 8996 (Day 42) | 44.5 (Day 42) | NA | 94 | 0.3–0.4 |
| ReiThera/LEUKOCARE/Univercells | GRAd-COV2 | Phase 2/3 | Italy | Phase 1 NCT04528641 | Intramuscular Single dose | 5 × 1010, × 1011 or 2 × 1011 | 90 | NA | NA | NA | NA | NA |
| University of Oxford/ AstraZeneca | ChAdOX1-nCoV | Phase 4 | England | Phase 2/3 NCT04400838 | Intramuscular: Single or two doses | 5 × 1010(prime), 2.2 × 1010 (boost) | 12390 | 9705–20713 (Day 28) | 144–193 (Day 42) | 100 | 61–88 | 0–4 |
| Gristone Oncology | ChAd68-S and ChAd68-S-TCE | Phase 1 | USA | Phase 1 NCT04776317 | Intramuscular: Two or three doses | 5 × 1010 or 1 × 1011 | 130 | NA | NA | NA | NA | NA |
| Bharat Biotech | BBV154 | Phase 1 | USA, India | Phase 1 NCT04751682 | Intranasal, single or two doses | 1 × 1010 | 175 | NA | NA | NA | NA | NA |
Numbers in parentheses refer to the day post-vaccination when antibodies were measured.
VP virus particles per participant, NCT national clinical trial, NA not available, RBD-specific ELISA Abs Receptor Binding Domain-specific Antibodies measured by Enzyme linked Immunosorbent Assay (ELISA), GMT of NAbs Geometric Mean Neutralizing-Antibody Titer against live SARS-CoV-2, %= percentage of the study participants, [AU]/mL arbitrary unit/milliliter.