On Friday Eastern Time, the American vaccine manufacturer Pfizer disclosed the latest progress of the company's "flu/COVID-19 combined vaccine" project, saying that the vaccine's third phase clinical trial failed to meet its main goals, which disappointed investors. Before the U.S. stock market opened, Pfizer's share price fell slightly by 0.3%, and BioNTech's share price fell by more than 4%.
Pfizer and German medical technology company BioNTech first launched a flu vaccine collaboration in 2018 and collaborated to produce the best-selling COVID-19 vaccine during the epidemic. They are now developing a combined vaccine to prevent both influenza and COVID-19.
But Pfizer and BioNTech's COVID-19/flu vaccine failed to meet a key goal in late-stage trials, posing risks to a much-anticipated product that will help the two pharmaceutical companies compete in the post-COVID-19 vaccine market.
Pfizer issued a statement on Friday saying that phase III clinical trials showed that compared with standard influenza vaccines, the combination vaccine triggered a strong immune response to influenza A, but did not provide effective immune protection against influenza B.
It is reported that the combined vaccine is based on BioNTech's proprietary mRNA platform technology and contains mRNA strands encoding the wild-type spike protein of SARS-CoV-2 and the BA.4/BA.5 spike protein of the Omicron sublineage, as well as mRNA strands encoding the hemagglutinins of four different influenza virus strains.
In this Phase III clinical trial, Pfizer recruited more than 8,000 adults aged 18 to 64 to evaluate the safety, tolerability and effectiveness of the combined vaccine. No safety issues were found.
Annalisa Anderson, Pfizer's head of vaccine research and development, said: "We remain optimistic about the combined influenza/COVID-19 vaccine program and we are evaluating next steps." The companies stated that they are discussing the study results with health authorities and will evaluate adjustments to the drug candidate to improve its effectiveness against influenza B.
Dr. Ugur Sahin, CEO and co-founder of BioNTech, stated: "We are committed to developing combination vaccines that provide broader protection against multiple respiratory diseases. The insights gained from this combination vaccine trial are extremely valuable and will play a key role in guiding the development of combination vaccine programs. We are committed to leveraging our experience in developing mRNA vaccine candidates and believe we can successfully complete this task with our partner Pfizer."
Analysts commented that the poor performance of Pfizer's combined vaccine in late-stage trials may put it at a disadvantage in competition with Moderna, and that the redesigned combination may delay the launch of Pfizer's combined vaccine by at least two years.
In June of this year, Moderna announced that its combined COVID-19/influenza vaccine was as effective as the individual vaccines, meaning the mRNA vaccine maker was able to apply for licensing for its third product.
Moderna said that in a Phase III clinical trial studying the antibody responses of more than 8,000 adults aged 50 and older, its combination vaccine was proven to be as effective as the company's new coronavirus vaccine alone and two commonly used seasonal influenza vaccines, Fluzone and Fluarix, that are selectively administered to different age groups.