14/15 December 2023
Currently, the increasing emergence of new SARS-CoV2 variants is presenting new challenges to medicine, health authorities and also vaccine manufacturers. On 22 February, the FDA, as the relevant US-American authority, published a series of appropriately amended guidance documents containing recommendations for the developers and manufacturers of COVID-19 vaccines.
On 25 February, the EMA followed at the European level and published a corresponding guidance document "Regulatory requirements for vaccines intended to provide protection against variant strain(s) of SARS-CoV-2" and also referred to a number of other related documents, such as:
It is emphasised that the three vaccines currently licensed in the EU from BioNTech/Pfizer, Moderna and Astra Zeneca are effective against the variants currently present in Europe. However, it is prudent to also prepare for the fact that as the number of mutations increases, adjustments to the vaccines will also be necessary to ensure adequate protection of the population.
Assuming that with the platform technologies currently in use, the basis of the vaccine would remain the same and the difference would only lie in the "antigen", an accelerated approval would then be conceivable.
As far as clinical data are concerned, large-scale safety and efficacy studies would then no longer be necessary. The efficacy of variant vaccines should therefore be proven in immunogenicity studies in which the immune response triggered by the variant vaccine against the variant virus is to be investigated.
Regarding quality and manufacturing, the EMA says here: "The variant vaccine is expected to be produced by the same manufacturer, and in line with processes and controls used for the parent vaccine. The manufacturer will need to generate data that show that the quality of the variant vaccine complies with the standards set for the parent vaccine. In the case of a multivalent vaccine - one that contains different viral variant strains - additional evidence may be required to ensure the quality of the active substances and the finished product."
More details on SARS Cov2 variant vaccines can be found on the EMA website.