Pfizer Inc. and BioNTech SE announce 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.
Key highlights:
- Omicron-adapted monovalent candidate given as a fourth booster dose elicited a 13.5 and 19.6-fold increase in neutralising geometric titers against Omicron BA.1 at 30 µg and 60 µg dose levels; bivalent vaccine candidate exhibited a 9.1 and 10.9-fold increase against Omicron.
- The data show the ability of our monovalent and bivalent Omicron-adapted vaccine candidates to significantly improve variant-specific antibody neutralisation responses.
- Preliminary laboratory studies demonstrate both Omicron-adapted candidates neutralise Omicron BA.4 and BA.5 though to a lesser extent than they do for BA.1.
- Both vaccine candidates demonstrated a favorable safety and tolerability profile similar to the Pfizer-BioNTech COVID-19 Vaccine.
- Data to be discussed with regulators with goal of rapidly introducing adapted booster to address current and future variants.
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 authorised by regulators.”
“The data show the ability of our monovalent and bivalent Omicron-adapted vaccine candidates to significantly improve variant-specific antibody neutralisation 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.”
The Omicron adapted vaccine candidates (30 µg and 60 µg) studied in the Phase 2/3 trial in 1,234 participants 56 years of age and older elicited substantially higher neutralising antibody responses against Omicron BA.1 when compared to the companies’ current COVID-19 vaccine. The pre-specified criterion for superiority was measured by the ratio of neutralising geometric mean titers (GMR) with the lower bound of the 95% confidence interval >1. The geometric mean ratios (GMRs) for the monovalent 30 µg and 60 µg vaccines compared to the current COVID-19 vaccine were 2.23 (95% CI: 1.65, 3.00) and 3.15 (95% CI: 2.38, 4.16), respectively. The GMRs for the bivalent 30 µg and 60 µg vaccines compared to the current COVID-19 vaccine were 1.56 (95% CI: 1.17, 2.08) and 1.97 (95% CI: 1.45, 2.68), respectively. The monovalent Omicron-adapted vaccine 30 µg and 60 µg achieved a lower bound 95% confidence interval for GMR of >1.5, consistent with the regulatory requirement of super superiority. Demonstration of superiority against Omicron and safety are regulatory requirements for potential emergency use authorization of a variant-adapted vaccine.
One month after administration, a booster dose of the Omicron-adapted monovalent candidates (30 µg and 60 µg) increased neutralising 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 neutralising 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 neutralisation assay tested on sera from participants over 56 years of age and older, sera efficiently neutralised 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 previous weeks.
These results were shared with the U.S. Food and Drug Administration (FDA) and European Medicines Agency (EMA) in advance of upcoming discussions with the FDA Vaccines and Related Biological Products Advisory Committee (VRBPAC) on June 28 and with the International Coalition of Medicines Regulatory Authorities (ICMRA) on June 30. The companies also submitted additional data from their ongoing COVID-19 booster studies, including data on an additional dose of their current COVID-19 vaccine and Beta candidate, to further demonstrate the flexibility and potential benefit of mRNA-based vaccines.
The Pfizer-BioNTech COVID-19 Vaccine, which is based on BioNTech’s proprietary mRNA technology, was developed by both BioNTech and Pfizer. BioNTech is the Marketing Authorisation Holder in the United States, the European Union, the United Kingdom, Canada and other countries, and the holder of emergency use authorisations or equivalents in the United States (jointly with Pfizer) and other countries. Submissions to pursue regulatory approvals in those countries where emergency use authorisations or equivalent were initially granted are planned.