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an improved level of cross-neutralization against previous VOCs as well as current

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Omicron and possibly future Omicron sublineages in the Northern hemisphere

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winter season of 2022. While initial recommendations might be restricted to

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booster doses, additional data may enable using adapted vaccines also to be used

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for primary series in the future.

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In addition, there might be a possibility that vaccines with a different VOC

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included, e.g. Beta, could still provide an adequate immune response to Omicron

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and its subvariants and could be considered for regulatory approval. Moreover, it

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is not excluded that different types of strains could be prevalent among regions,

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which might require some regional flexibility for selection of variants incorporated

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in vaccines.

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Effectiveness studies with variant-adapted vaccines should be conducted to

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determine the level of protection conferred over time in real-life conditions

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against different clinical endpoints such as disease, hospitalization and death.

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Furthermore, depending on vaccine availability and national recommendations,

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as a general principle, elderly and vulnerable populations should be prioritized in

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the vaccination campaigns ahead of the Northern hemisphere winter season.

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Finally, regulatory strategies for approval of variant vaccines will be fine-tuned in

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the future considering the experience gathered so far with various vaccine

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compositions and across different platform technologies.

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