Pfizer Inc. and BioNTech SE announced positive data evaluating the safety, tolerability, and immunogenicity of two Omicron-adapted COVID-19 vaccine candidates: one monovalent and the other bivalent, a combination of the Pfizer-BioNTech COVID-19 Vaccine and a vaccine candidate targeting the spike protein of the Omicron BA.1 variant of concern. Data from the Phase 2/3 trial found that a booster dose of both Omicron-adapted vaccine candidates elicited a substantially higher immune response against Omicron BA.1 as compared to the companies’ current COVID-19 vaccine. The robust immune response was seen across two investigational dose levels, 30 µg and 60 µg.
“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,” said Albert Bourla, Chairman and Chief Executive Officer, Pfizer. “Based on these 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 these data with the scientific community and health authorities so we may rapidly introduce an Omicron-adapted booster as soon as possible if authorized by regulators.”
“The data show the ability of our monovalent and bivalent Omicron-adapted vaccine candidates to significantly improve variant-specific antibody neutralization responses,” said Prof. Ugur Sahin, M.D., CEO and Co-founder of BioNTech. “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.”
One month after administration, a booster dose of the Omicron-adapted monovalent candidates (30 µg and 60 µg) increased neutralizing geometric mean titers (GMT) against Omicron BA.1 13.5 and 19.6-fold above pre-booster dose levels, while a booster dose of the Omicron-adapted bivalent candidates conferred a 9.1 and 10.9-fold increase in neutralizing GMTs against Omicron BA.1. Both Omicron-adapted vaccine candidates were well-tolerated in participants who received one or the other Omicron-adapted vaccine.
In a SARS-CoV-2 live virus neutralization assay tested on sera from participants over 56 years of age and older, sera efficiently neutralized BA.4/BA.5 with titers approximately 3-fold lower than BA.1. Pfizer and BioNTech will continue to collect additional study data on Omicron BA.4/BA.5 over the coming weeks.
