Novartis Says Swine Flu Virus Gives Poor Harvest For Vaccine
Lab workers are harvesting one dose or less of the component they need from each egg in which the virus is grown, said Eric Althoff, a spokesman for the Swiss drugmaker. Thats between a third and half of the typical yield for a seasonal flu vaccine, he said.
The low yield may slow production of a pandemic vaccine because it means drugmakers like Novartis, Baxter International Inc., Sanofi-Aventis SA and GlaxoSmithKline Plc can extract less of the protective ingredient from each egg. Baxters Chief Executive Officer Robert Parkinson and a spokesman for Sanofi also said yesterday the amount of swine flu virus growing in each egg is lower than for seasonal flu.
The World Health Organization, whose labs supplied the virus to drugmakers, is trying to produce samples that yield more antigen.
“There is work ongoing to improve them,” Novartis Chief Operating Officer Joerg Reinhardt said yesterday on a conference call. “But its very difficult to predict what it will be at the end.”
The H1N1 virus, also known as swine flu, is sweeping the southern hemisphere as tens of thousands of patients test positive for the virus in Australia, Argentina, Chile and other countries. Its also spreading in the north outside of the usual flu season. The U.K.s most senior doctor yesterday said the health service is planning for 65,000 deaths from the disease, which has claimed 429 lives worldwide.
Bad Yielder
“The industry at large is challenged,” Baxters Parkinson said yesterday.
Most manufacturers make flu vaccines by injecting chicken eggs with an approved version of the virus to provide it with nutrients to grow and multiply. The amount of virus that grows in the egg and can be turned into shots is called its yield.
All government vaccine orders include a set yield assumption, Andrin Oswald, who heads Novartiss vaccine unit, told reporters yesterday. One egg will usually produce enough antigen to make two doses of seasonal flu vaccine, according to Oswald.
“It is well known that some strains are good yielders, and some strains are bad yielders,” Marie-Paule Kieny, director of the WHOs Initiative for Vaccine Research, said in a teleconference on July 13.
“Unfortunately we didnt come up with a good yielder in the first series of strains,” she said. “To remedy that, the WHO laboratory network is again trying to generate new vaccine viruses” from patients who have been infected. “We hope that one of them will be giving higher yields, comparable to the ones obtained with seasonal vaccines.”
Vaccine Revenue
The yield also determines the shots potential revenue. Novartis swine flu vaccine sales could be worth between $1 billion and $1.5 billion if a single dose is sold for $10, Karl Heinz Koch, an analyst at Helvea SA in Zurich said in a note to clients today. Novartis has not added this revenue to the current sales outlook, Chief Financial Officer Raymund Breu said on a conference call yesterday.