Sanofi-GSK COVID booster outperforms Pfizer/BioNTech vaccine against Omicron
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Sanofi (NASDAQ:SNY) (OTCPK:SNYNF) said on Monday that an upgraded version of a COVID-19 vaccine the company is developing with GSK (GSK) worked better than Pfizer (PFE)/ BioNTech (BNTX) vaccine as a booster shot against the Omicron variant.
The 247-subject study was designed to evaluate the effect of Sanofi-GSK first and next-generation recombinant booster vaccine candidates and that of a 3rd dose of the Pfizer (PFE)/ BioNTech (BNTX) vaccine in those who initially received two doses of the mRNA-based vaccine.
All three vaccines generated neutralizing antibodies against the Omicron BA.1 variant. However, Sanofi-GSK next-gen candidate generated the highest response, according to data published as a pre-print ahead of a peer review.
Another late-stage trial involving 1,500 of those who have previously received mRNA vaccines, such as those from Pfizer (PFE)/BioNTech (BNTX) and Moderna (MRNA), indicated that the new vaccine candidate led to a sizable increase in antibody levels against several variants of concern.
According to early data, there was a 40-fold increase in antibody titers against the BA.1 variant, and the new vaccine version doubled the number of neutralizing antibodies against Omicron BA.1 and BA.2 compared to the original vaccine candidate.
Both studies showed that the experimental vaccine was well tolerated with a favorable safety profile. However, the cohort of 1,500 subjects in the second trial indicated less than 4% of Grade 3 reactions, which, according to Sanofi (SNY), were temporary and non-severe.
The first recombinant vaccine candidate developed by Sanofi (SNY) and GSK (GSK) is currently undergoing European regulatory review for COVID-19.
Read about the prospects of the Sanofi-GSK vaccine against widely used mRNA vaccines.