Wendy Wolfson
Newswire21.org
Within a few years, millions of chickens will retire from the vaccine business, leaving much of their work to the dogs.
Vaccine manufacturers are switching from making flu vaccine in eggs to making it with the help of cells from other species, including dogs. And, within a decade, synthetic or recombinant technologies may replace cell-based methods
As things stand now, experts place their bets on the most likely combination of flu virus variants months before each flu season begins. They then grow vaccine in chicken eggs. Millions of additional chickens were drafted for this year's H1N1 pandemic but the slow-growing virus stymied production. For several weeks, H1N1 vaccine supplies lagged behind demand.
In the past few years, the Department of Health and Human Services has invested $1.3 billion in developing newer cell-based influenza vaccine manufacturing.
"Many if not most if not all of the companies are ultimately making the transition out of eggs and into cells." said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases. "Some companies like Novartis are much further advanced in their transition process."
New Plant
Novartis cut the ribbon on its billion-dollar Holly
Springs, NC, factory this year, where influenza vaccine will be produced in dog
cells.
While cell-based manufacturing only shaves off about 2 weeks from production, Fauci said it offers extraordinarily good surge capacity - the ability to quickly produce large quantities of vaccine in case of a pandemic. FDA licensure of cell-based manufacturing, "is slow and deliberate," said Dr. Jose Romero, a member of the FDA advisory panel, speaking in an unofficial capacity.
Concerns include ensuring cell lines used for growth substrate are clean of rogue viruses, called "adventitious agents." Vaccines for mumps and measles are commonly grown in cell culture. However, each cell line has to be evaluated on its own.
"Cell-based manufacturing is close to being prime time, close to being licensed in this country," said Dr. Robin Robinson, director of the Biomedical Advanced Research and Development Authority (BARDA).
'Surge' Strategy
In addition to producing seasonal influenza vaccine, BARDA requires its large
manufacturers to have the surge capacity for 150 million doses of cell-based
pandemic vaccine and smaller biotechs to be able to produce 50 million doses of
recombinant-based pandemic vaccine.
Robinson predicts the two most advanced manufacturers will apply for FDA approval to sell in the US by 2011. Novartis is completing validation of its North Carolina facility. Baxter also is considering building a cell-based manufacturing facility in the US.
But cell-based manufacturing is only the first stage in a multistep plan. HHS is evaluating DNA recombinant technologies that don't involve growing virus at all.
These include vaccines using synthetic peptides, DNA-based vaccines, recombinant subunit vaccines, microbial vector vaccines, and virus-like particle technology.
Robinson estimates that some molecular and recombinant technologies may be five to eight years from commercial production.
Some are intriguingly close. Protein Biosciences, a biotech that uses a baculovirus, an insect virus vector to produce influenza vaccine in insect cells has now applied for FDA licensure. According to Fauci, the end game is to to develop a universal vaccine "where you don't have to change the vaccine from season to season or even from seasonal to pandemic."
