“We started collaborating with BioNTech to develop messenger RNA vaccines in 2018, before the pandemic,” recalls Annaliesa Anderson, Pfizer's chief scientific officer for vaccines. The initial goal was to create a flu vaccine. That collaboration allowed Pfizer and BioNTech to react quickly at the start of the pandemic and be the first companies to have a covid vaccine ready. Anderson speaks to La Vanguardia on March 9 at the Pfizer vaccine factory in Puurs, Belgium.
Where is the flu messenger RNA vaccine project now at?
It is in a phase 3 clinical trial [the last phase before the vaccine can be approved]. It is a trial with 36,200 participants over the age of 18 in the United States. We hope to have results this year and to have the vaccine approved in time for the next flu season in the Northern Hemisphere in fall 2024. Assuming that the clinical trial results are positive.
Will it replace current flu vaccines?
We think that it can substantially improve the current situation because some years the flu vaccines have a relatively low efficacy.
What makes you hope that mRNA vaccines will be more effective?
There are two reasons. The first is that the composition of current flu vaccines has to be decided well in advance because it takes six months to produce them. In this time the flu virus evolves, so in some years the vaccines are not well adapted to the viruses that end up circulating. This happened in 2008, 2015 and 2020, for example. With messenger RNA vaccines we can reduce the time from six months to three months. With this we can ensure that vaccines are better adapted to the viruses that circulate and are more effective.
But it is the WHO that says what composition flu vaccines should have. If you delay the decision, other producers will not be able to supply the vaccine on time.
We are working with the WHO to see how the time frame can be reduced.
And the second reason?
Current flu vaccines are produced in chicken eggs. Some years vaccines have limited efficacy due to mutations related to adaptation to eggs. It happened in 2016, 2017 and 2018. With messenger RNA technology we will not have this limitation.
Let's move on to covid. Do you foresee vaccination becoming annual?
We are working on a combined covid and flu vaccine so they can be given together if covid becomes an annual immunization. It is in phase 1 clinical trials.
That is a yes?
It is expected that a respiratory virus will end up having a seasonal distribution of cases. This is what we see with other respiratory viruses.
What led you to partner with BioNTech before the pandemic?
BioNTech is an innovative and agile company looking to accelerate the development of its messenger RNA platform. At Pfizer we have a 170-year tradition of developing vaccines [when the company was not yet called Pfizer], we have a strategy to create new vaccines to respond to neglected medical needs, and we have research, production, legal regulation, and marketing capabilities. that could accelerate the development of the innovations arising from BioNTech. It is a very positive collaboration, as has been seen with the covid.
Do you consider the flu a neglected medical need?
It causes between three and five million serious cases a year in the world. In Europe alone, it is estimated that it causes between 15,000 and 70,000 deaths a year and that it has an economic cost of 6,000 million euros.
Have you started working on a vaccine against the H5N1 bird flu virus to be prepared if it spreads from person to person and causes a pandemic?
With covid we have shown that, if necessary, we can produce a vaccine very quickly, within 110 days.
Does this mean that they have not started producing it?
We do not have licensed flu vaccines at this time. But messenger RNA is an excellent technology for making vaccines against viruses like flu. On the other hand, it is not for producing vaccines against bacteria. As I tell you, we can respond quickly if necessary in the event of a flu pandemic.
Does it seem feasible to get a universal vaccine against all flu viruses so that none can cause a pandemic?
There are many people researching in this field. Influenza viruses are so variable that a universal vaccine will be hard to come by. But if a greater diversity of proteins from influenza viruses is included in vaccines, it is possible to think of achieving a broader protection.
And a universal vaccine against coronaviruses to prevent pandemics caused by this type of virus?
There are many coronaviruses in nature. The problem is how we can predict which antigen we need to include in a vaccine for a virus that has not yet appeared. This is more difficult.
Are you preparing a vaccine against the Epstein-Barr virus [which causes mononucleosis, multiple sclerosis and some lymphomas]?
We need to better understand how the Epstein-Barr virus and the immune system interact to know what we could achieve with a vaccine. Attempts to immunize against this virus in the past have prevented mono, which is fine, but they haven't prevented infection. Therefore, we do not yet know if a vaccine would prevent long-term effects of infection such as multiple sclerosis and some cancers.
Couldn't infection be prevented with a new immunization technology like messenger RNA?
We do not know. The problem is that, to design a vaccine, you have to understand well what you want to prevent. With the Epstein-Barr virus, we still don't know enough.
Declaration of transparency: 'La Vanguardia' has attended the meeting of those responsible for the Pfizer vaccine program with journalists in Puurs (Belgium) invited by the pharmaceutical company
