Pfizer and BioNTech have shared positive results from a phase 2/3 trial of two Omicron-adapted COVID-19 vaccine candidates.
The data shows that a booster dose of both Omicron-adapted vaccines gave a considerably higher immune response against Omicron BA.1, compared to Pfizer/BioNTech’s current COVID-19 vaccine.
The phase 2/3 trial involved 1,234 participants aged 56 and older. One month after receiving a booster dose, the Omicron-adapted monovalent candidates significantly increased protection against Omicron BA.1, showing a 13.5 and 19.6-fold increase above pre-booster dose levels.
One vaccine is monovalent and the other is bivalent, made up from a combination of the Pfizer/BioNTech COVID-19 vaccine and a vaccine candidate designed to target the spike protein of the Omicron BA.1 variant.
Albert Bourla, chairman and chief executive officer, Pfizer, said: “As we’ve said since the early days of the pandemic, we will follow the science and adapt our own approaches as needed to help address COVID-19 as the virus evolves.
“Based on this data, we believe we have two very strong Omicron-adapted candidates that elicit a substantially higher immune response against Omicron than we’ve seen to date. We look forward to discussing this data with the scientific community and health authorities so we may rapidly introduce an Omicron-adapted booster as soon as possible if authorised by regulators.”
Professor Ugur Sahin, chief executive officer and co-founder of BioNTech, said: “The data shows the ability of our monovalent and bivalent Omicron-adapted vaccine candidates to significantly improve variant-specific antibody neutralisation responses,” said
He added: “Omicron has newly evolving sublineages that have outcompeted BA.1 and exhibit a trend of increasing potential for immune escape. We will therefore remain vigilant and are prepared to rapidly adapt our Omicron-adapted vaccine candidates to emerging sublineages if epidemiological and laboratory data suggest.”
The two companies will collect additional study data on Omicron BA.4/BA.5 over the coming weeks.
The latest results will be shared with the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) ahead of discussions with the FDA Vaccines and Related Biological Products Advisory Committee on 28 June and with the International Coalition of Medicines Regulatory Authorities on 30 June.