With this season’s flu vaccine protecting only one in 4 people, scientists are working on new manufacturing techniques and virus-killing methods to update the creaky, 80-year-old process now used to inoculate the population.
Sometime this season, after many people got vaccinated, a strain of influenza that causes unusually serious illness evolved, letting the bug circumvent a protection that is still only about 60 percent effective in a good year. This year’s vaccine is much worse, at just 23 percent, according to the U.S. Centers for Disease Control and Prevention.
To make the vaccine more effective, scientists and companies are reworking everything from its production to its distribution to the way it attacks the virus. The goal is to find methods that offer more protection and can react more quickly to unexpected changes.
The flu virus can replicate in eight hours, so when it mutates, the change can slip past people’s immunity and quickly become dominant, said Ruben Donis, associate director for policy, evaluation and preparedness in the CDC’s influenza division. That makes it difficult for the world’s flu experts, who meet every February to formulate a vaccine for the next flu season in North America, as little as eight months away.
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“If we can deliver 140 million doses to our network of pharmacies and clinics and all the health-care providers, we could probably wait until May or June to make a decision,” Donis said. “But that’s impossible the way things are now.”
They have to meet so early because GlaxoSmithKline, Sanofi and the four other manufacturers of traditional vaccines need that much of a head start to pull off a new vaccine every year. The companies first must grow enough of the virus to make an effective vaccine. Then in most cases they use formaldehyde to break the virus into pieces, rendering it unable to sicken people while still eliciting an immune response that protects them from the whole virus. Finally, vaccine makers purify the result.
Using a process discovered in 1931 and used in vaccines since 1935, manufacturers grow the virus by getting it to replicate in chicken eggs. That typically takes about a month, but can take weeks longer if the year’s dominant viruses don’t thrive well enough in the eggs, said Leonard Friedland, director of scientific affairs and public health in GlaxoSmithKline’s North American vaccines division.
So why not just find a way to make manufacturing shorter? Two companies – Novartis AG and Protein Sciences Corp. – are already on it, with approval to sell vaccines in the U.S. that take just weeks to produce.
Still, they represent a small share of the market, which remains dominated by the doses made using the traditional six-month egg process. Novartis’s cell-culture vaccine was approved in the U.S. in 2012, and its U.S. production plant was licensed by the Food and Drug Administration last year.
Protein Sciences’ Flublok vaccine, made with a technology that manufactures the proteins that provoke an immune response without first growing the entire virus, was approved for all adults in October. The closely held company plans to increase production to be able to supply enough doses for the entire country in two years, Chief Executive Officer Manon Cox said in an interview.
It will take a while for new technology to catch on and for vaccine buyers to become comfortable with it.
“We’ve been doing this for 40-plus years and it has never failed us,” David Greenberg, chief medical officer at Sanofi Pasteur, the Paris-based drugmaker’s vaccine division, said in an interview. “There’s a lot to be said for a system that has never failed. If you’re going to change, you have to make sure it is as reliable.”
Production isn’t the only way to speed up the vaccine process. Faster distribution could also help, perhaps with delivery mechanisms that would eliminate the hassle of handling a liquid vaccine that needs to be refrigerated. For example, researchers at the Georgia Institute of Technology and Emory University have worked on a patch that delivers the vaccine through the skin.
To get ahead of the virus once and for all, the CDC’s Donis sees researchers stepping away from the classic vaccine strategy of mimicking people’s natural process of gaining immunity to diseases they encounter. Scientists could combat the virus by altering the behavior of immune cells, which respond to the proteins on the surface of a pathogen such as the flu virus.
If scientists can teach those cells to look deeper, a vaccine could create an immune response that would recognize the influenza virus even when its outer form varies – either because of mutations such as this season’s, or just because there are hundreds of versions of the virus that circulate in any given flu season. (The CDC counted 355 this season through Oct. 1.)
While such a vaccine is called the holy grail by researchers, it is still in early-stage animal testing at the FDA.
“In the past we’ve been copying what happens in nature,” Donis said. With new vaccine research, “We are asking the vaccine to accomplish something that is not already accomplished in nature.”