For more than 40 years, flu vaccine has been made by injecting virus into fertilized chicken eggs. It's no accident that Wyeth's shuttered plant, and Aventis's operating one, are both in Pennsylvania, the state with the third-largest egg production in the country. Each egg must be hand-inspected and hand-injected. One egg grows enough virus for 4 or 5 doses of vaccine. Millions are needed. The final shot is three vaccines packaged as one: two strains of influenza A and one of B.
Each round of production using this old-fashioned technology is known as a "campaign." The name is well-chosen. They have some of the risk, time pressure and uncertainty of political races and military attacks.
For two decades, Wyeth made injectable influenza vaccine at this plant in Marietta, Pa., which it eventually closed.
(Kalim A. Bhatti -- The Philadelphia Inquirer)
The uncertainty, though, isn't just at the production end. It is also in the market.
In 1999, supply and demand were evenly matched -- only 400,000 doses of 77 million went to waste. The next year, though, 8 million were thrown out. In 2001-02, 10 million doses were pitched. The next year (Wyeth's last) the number was 13 million. Last winter, despite a run on vaccine in an earlier-than-usual flu season, 4 million doses, out of 87 million made, were discarded.
The waste is particularly hard for vaccine makers to stomach because their profit margin is small. Flu shots are essentially commodities -- identical products made by numerous companies and differing only in price. Because much of the vaccine is bought in huge orders by government agencies, the price is low.
Over three seasons, Wyeth lost $50 million from unsold flu vaccine. It was also facing millions of dollars in required improvements to keep its plant up to standards required by the Food and Drug Administration.
Getting out of the business "certainly wasn't a no-brainer -- we do not make decisions like that lightly," Wyeth's Paradiso said. But, he added, "We were finding that there was not, in fact, a market for our product."
Chiron, which wouldn't discuss its business strategy for this article, apparently had a different view of the flu market.
Experts say the California-based company saw in the dwindling interest in flu vaccine an opportunity to make money, which it could then funnel into its main work: developing biotech products. This appeared to be possible if it could acquire an existing plant, which it did -- in Liverpool.
The strategy might have paid off handsomely if the company hadn't run into the contamination problems. That's because the market for flu vaccine is big, and growing.