June 13, 2022

expert reaction to press release from Sanofi on the Sanofi-GSK COVID-19 booster and measures of immune response against variants of concern

Sanofi has reported data from two trials conducted with its new next-generation COVID-19 booster vaccine candidate modelled on the Beta variant antigen and including GSK’s pandemic adjuvant.

Prof Stephen Evans, Professor of Pharmacoepidemiology, London School of Hygiene & Tropical Medicine, said:

“This announcement is interesting and encouraging news.  A company trial and an independently conducted trial (though partially funded by Sanofi) report similar encouragement.

“There is a pre-print of a paper on the independent trial, so focussing on that, the results show that a new booster vaccine targeted at the Beta variant shows good antibody results not only against the original wild type (Wuhan) strain but, as expected good antibody results against the beta strain.  Neither of these strains are circulating now but there are also good results, and better than boosters using the original strain, against the Delta and Omicron BA.1 variants.  (The press release mentions BA.2 but the paper does not).

“These results are not totally unexpected, and while encouraging, should be viewed with some caution, as the authors of the paper in pre-print state.  The main cautions relate to a) the study looked at antibody results only up to day 15 after vaccination and b) the fact that we do not know for certain that the antibody results will translate into clinical effectiveness (prevention of illness, hospitalisation or death), though this is a reasonable likelihood given our current knowledge.”

https://www.sanofi.com/en/media-room/press-releases/2022/2022-06-13-05-30-00-2460833

https://www.medrxiv.org/content/10.1101/2022.05.25.22274904v1

Declared interests

Prof Stephen Evans: “No conflicts of interest specific to these studies.  I am funded (one day per week) by LSHTM.  They get funding from various companies, including Astra Zeneca and GSK but I am not funded by them, I have no involvement in obtaining funding from them and I am not an investigator on any grants obtained from them.  I am the statistician to the ‘meta-Data Safety and Monitoring Board’ for CEPI.  I am paid for my attendance at those meetings and will be paid expenses for travel if that occurs.  I am a participant in the Oxford/Astra Zeneca trial, and on 13th January 2021 learnt I had received the active vaccine.”