“Much stronger immune response”
“We believe we have two very strong omicron-matched candidates that elicit a significantly stronger immune response against omicron than we have seen to date,” Pfizer CEO Albert Bourla wrote on Twitter.
“We look forward to discussing this data with the scientific community and health authorities so that we can bring an omicron-adapted booster to market as soon as possible if it is approved by the regulatory authorities.”
On the website, the two companies write that the Omicron-adapted monovalent vaccine candidate, administered as the fourth booster dose, resulted in a 13.5- and 19.6-fold increase in neutralizing geometric titers against Omicron BA.1 at one month. Of the bivalent vaccine candidate showed a 9.1- and 10.9-fold increase against omicron.
Neutralizing at BA.4 and BA.5
Preliminary laboratory studies show that while the two vaccine candidates neutralize the currently rampant omicron subvariants BA.4 and BA.5, they do so to a threefold lower degree than BA.1.