After Covid, Researchers Turn mRNA Vaccines To Flu Shots
The mRNA vaccine technology that brought the Covid-19 vaccines online in record time are now being eyed for revolutionizing the common flu shot.
The technology used in two of the coronavirus vaccines authorized by the Food and Drug Administration may enable scientists to develop flu shots in record time, but also make inoculations that could be more effective and protect against numerous flu strains for years at a time.
The messenger-RNA technology — used in the Pfizer and Moderna coronavirus vaccines — would be a leap forward for flu shots, some of which still rely on a process developed in the 1950s involving chickens, petri dishes and dead viruses.
Researchers are hopeful that the success of those coronavirus vaccines will grease the wheels for mRNA flu shots and help expedite what is typically a lengthy process involving years of research, clinical trials and regulatory review and approval.
“It’s a very obvious progression given the success of the covid-19 vaccine to move right to flu,” said Andrew Pekosz, a professor of microbiology at the Johns Hopkins Bloomberg School of Public Health.
But researchers say the development and approval of an mRNA flu shot may take some time.
The idea that scientists can use messenger RNA for medical therapeutics is not new. Flu shots using mRNA technology have been in development for years.
In 2018, for example, Pfizer and BioNTech announced a partnership to start developing an mRNA vaccine that would prevent influenza. Moderna is working on a number of different mRNA vaccines, including one for the flu.
But using mRNA for vaccines shifted from experimental to critical last year. With a pressing need spurred by a global pandemic and billions of dollars in funding for vaccine development, scientists were able to repurpose their knowledge of mRNA to develop coronavirus vaccines.
“People who were slogging away for many years had money thrown at them to get it done. And they became laser-focused to bring something to market that would have ordinarily taken years,” said Paul Duprex, director of the Center for Vaccine Research at the University of Pittsburgh.
Currently, the most common influenza vaccine that is available in the United States is manufactured using an inactivated, or killed, virus and administered via a shot in the arm. But there is also a vaccine that uses a live, but weakened, virus and is given in the form of a nasal mist.
The flu viruses for these vaccines are grown in chicken eggs or in cells inside a petri dish. The viruses are then killed or weakened, and the resulting proteins — the important ingredient in the vaccine — are purified. When the shot is administered, the immune system starts making antibodies against those proteins.
“But the mRNA vaccine is very, very different,” Pekosz said, explaining that mRNA vaccines can teach the immune system to fight a virus without ever coming into contact with it. They can also “generate a much stronger immune response than responses that are generated to the protein in a normal flu vaccine,” he added.
The biggest problem for moving the mRNA technology into other vaccines may be the storage conditions. The Pfizer vaccine is the pickiest — -70 °C and less than a week once thawed — but Moderna’s not that much better. It’s one thing in a pandemic where every dose they can deliver is oversubscribed. I understand that with current-gen flu vaccine, even with much less stringent storage requirements, many doses are discarded.Report
Are the storage conditions inherent to the mRNA technology? Or is that something that future iterations of the technology may be able to address?
As I understand it, the efficacy of the flu vaccine really varies based on a number of factors*. If the mRNA technology can dramatically improve that, it may be worth pursuing even with the storage challenges. If it won’t change that and is merely a fun way to use this shiny. new toy, then we probably don’t want to go down that path. Not yet, at least.
* I’ve read that the development of this coming flu season’s vaccine may be hampered by the dramatically reduced number of flu cases scene during the pandemic. As I understand it, the scientists use the prior year’s strains to help predict the next year’s strains and they have very limited data. We’ll see what the eventual fallout of that is but if mRNA technology can help resolve that, that alone may make it worth it for this year at least.Report
Lots of freezer capacity just got installed, though, exactly for this.
And mRNA tech has a lot of potential, and we just stress tested the crap out of it’s basic concept in terms of unforeseen problems.
That doesn’t mean any given mRNA vaccine doesn’t need to be tested or can’t have problems, but we validated the underlying concept pretty thoroughly. A ridiculous wealth of data on efficacy, short and long term side effects, duration, etc. Creating mRNA vaccines is pretty fast once you’ve identified the target (the specific proteins or surface the vaccine is aimed at), and what we did in a year for COVID-19 could be done in half the time in the future now that a lot of basic data has been delivered.
Effectively, we’re talking a highly modular vaccine framework where you can plug in the target you’re looking for easily, and then roll out.
And looking ahead further, we might actually get something we can use against stuff like HIV — either as a vaccine or even a longer-term suppressant. Even bespoke cancer vaccines and therapies, targeted to your specific cancer profile.
It’s a big, big deal and I suspect the CDC will be pushing to fund keeping those cryogenic storage and distribution methods as a worthwhile investment.Report
I didn’t mean to understate the potential of mRNA. Only that at this point in time, there are a number of new logistics problems to solve before you just casually drop into the grocery pharmacy any time between September and April and get your cheap flu shot.Report