Exploration of Immunology

From: Vaccine efficacy—the biggest challenge today

Table 2. Examples of SARS-CoV-2 variants and COVID-19 vaccine efficacy.

Vaccine	Variants	Findings
WV
VLA2001	Delta, omicron	Improved VE for homologous/ChAdOx1 nCoV-19 boosters [126]
Protein subunit
NVX-CoV2373	D614G, BQ1.1, XBB.1	High PsVNA for D614G, low for BQ.1 and XBB.1 after booster in persons previously vaccinated with Ad and mRNA vaccines [127]
Viral
ChAdOx1	Beta	No protection against mild-to-moderate COVID-19 [128]
nCoV-19	Alpha, delta	Lower transmission reduction for delta than alpha, better VE for BNT162b2 than for ChAdOx1 nCoV-19 [129]
Ad26.COV2.S	Beta, gamma	Reduced nAb responses compared to original strain [130]
Ad26.COV2.S	Delta	Durability of VE for at least 6 months [131]
DNA
INO-4800	Delta, alpha, beta, gamma	Comparable nAb responses for gamma and original strain, 2.1-fold (alpha) and 6.9-fold (beta) reduction [132]
INO-4802	Alpha, beta, gamma	Enhanced nAb responses for variants and original strain [133]
RNA
BNT162b2	Delta	67% VE in Spain [134], 90% in the UK [135]
BNT162b2	BA.1, BA.2	VE 25% in US [136], 30% in Israel [137], 51% in Qatar [138]
mRNA-1273	Alpha, beta, gamma, delta	1.2-fold (alpha), 2.1- to 8.4-fold (beta, gamma, delta) reduction in nAb titers compared to D614G [139]
mRNA-1273.214	BA.1, alpha, beta, gamma, delta	Enhanced nAb titers against omicron, higher binding activity against alpha, beta, gamma, and delta [140]
XBB.1.5	XBB.1.5, EG5	27-fold enhanced nAbs levels against XBB.1.5 and EG5 [141]
LNP-nCoVsaRNA	D614G, alpha	Protection against D614G and alpha in hamsters [142]

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Ad26: adenovirus serotype 26; COVID-19: Coronavirus disease 2019; LNP: lipid nanoparticle; nAbs: neutralizing antibodies; PsVNA: pseudovirus-neutralizing antibody; saRNA: self-amplifying RNA; SARS-CoV-2: Severe Acute Respiratory Syndrome Coronavirus 2; VE: vaccine effectiveness; WV: whole virus. Adapted from [2]. © Author(s) 2024. CC BY 4.0.

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