The US FDA fully approved the launch of new monovalent XBB strain COVID-19 vaccine COVID-19 | vaccine | unit price this fall
·In addition to the addition of the XBB strain, the Committee supports the deletion of the original COVID-19 strain from the vaccine. Vaccines containing only the XBB strain can improve vaccine efficacy and help optimize immune responses, as the human immune system is not affected by the reactions triggered by the original strain.
On June 15 local time, the advisory committee on vaccines and related biological products of the US Food and Drug Administration held a meeting. The consultants finally voted at 21:00 and thought that FDA should update the current COVID-19 vaccine to target a single XBB, and the new vaccine should be a univalent vaccine, no longer including the antigen of the original strain. The consultants believe that these new vaccines should also be able to prevent other variants of COVID-19. The FDA may update available vaccines within a few months based on changes in the strain.
Peter Max, director of the Biological Assessment and Research Center of the US Food and Drug Administration, said that although the COVID-19 infection rate has declined, this winter may become a problem. "We are worried that a new wave of COVID-19 epidemic may occur when the virus further evolves, the population's immunity further weakens, and there are more indoor activities in winter."
The FDA said that the public should be vaccinated with the autumn vaccine for COVID-19 on time, just like the new flu vaccine every autumn. Although at present, most people have either been infected or received at least one round of vaccination, new variants of COVID-19 are still emerging.
According to the data provided by Natalie Thornberg, a vaccine expert from the US Centers for Disease Control and Prevention, 6.2 million people in the US have been hospitalized for treatment due to COVID-19 since the beginning of the epidemic, resulting in 1.1 million deaths. She said that the situation has improved this year, but there are still some vulnerable groups, such as people who have not been vaccinated, people with impaired immune system, and people with diabetes, cardiovascular or nervous system diseases. People 65 years old and over also face the risk of reinfection, and the risk increases with age.
In addition to the addition of the XBB strain, the Committee supports the deletion of the original COVID-19 strain from the vaccine. Several members expressed their belief that adding these strains to vaccines does not have any advantages. Jerry Will, Director of the Virus Products Department of the FDA Vaccine Research and Review Office, stated that vaccines containing only the XBB strain can improve vaccine efficacy because the human immune system is not affected by the response triggered by the original strain, a phenomenon known as immune imprinting. "I do believe that removing the original strain will help optimize the immune response," he said.
In the future, COVID-19 vaccine may be provided together with influenza and RSV vaccine. It is expected that the FDA will soon issue more formal recommendations to vaccine manufacturers. Manufacturers will need to study new formulas and submit data to the FDA. If approved, the CDC will further clarify which age groups should receive this vaccine.
According to a report by The New York Times, an FDA spokesperson stated that if data supports the safety and efficacy of the new vaccine, it is expected to be launched before the end of September. However, vaccine manufacturers or the FDA have not yet discussed the potential impact of administering multiple vaccines simultaneously.
On June 8, China approved the world's first XBB COVID-19 vaccine, the Vikhin 3-valent XBB vaccine, in an emergency use authorization mode. It took 22 days from obtaining the clinical trial approval for drugs issued by the National Medical Products Administration of China on May 17th to obtaining emergency use authorization on June 8th.
According to vaccine manufacturer Wisk Biopharmaceuticals, the vaccine targets the XBB.1.5+BA.5+Delta variant.
According to the company's official press release, clinical trial data shows that the Wicksin 3-valent XBB vaccine can induce the production of high-level neutralizing antibodies against variants such as XBB.1, XBB.1.5, and XBB.1.9. After 14 days of inoculation, the protective effect against symptomatic COVID-19 disease caused by XBB. 1, XBB. 1.5, XBB. 1.9 and other variants is 93.28%. However, there have been no published clinical trial papers on the third phase of the vaccine so far.
Dr. Zhou Yebin, a genetic doctor at the University of Alabama, Birmingham, recently wrote an article titled "Key Points Analysis of the World's First XBB Vaccine", stating that "when using the Wickham trivalent vaccine as basic immunity, two doses are far less effective than three doses." In the first phase of clinical trials, in terms of neutralizing antibody titers against the original strain, the two dose group receiving two doses every 28 days was only 2.3, and the three dose group receiving one dose every 14 days was 102.9.
In the second phase of the trial, the two dose group was changed to receive a second dose every 21 days, but the neutralizing antibody titer in the high-dose group was still only 3.6, far lower than the 102.6 in the three dose group. The conversion rate of antibodies in the two needle group is also relatively low, with a conversion rate of only 69% for binding antibodies and 49% for neutralizing antibodies. "Three doses are needed to induce significant neutralizing antibodies, which means that the vaccine has low immunogenicity from a technical perspective," Zhou Yebin wrote.
