By Kendra Marr
Washington Post Staff Writer
Wednesday, August 27, 2008
Novavax said yesterday that its bird flu vaccine elicited a robust immune response in humans, moving the biotech a step closer to licensing its pandemic vaccine production system.
In the trial, 160 patients received two vaccine injections, of 15 to 90 micrograms, one month apart. Of the patients who received the highest dosage, 94 percent produced antibodies to neutralize H5N1, an Indonesian strain of bird flu that emerged in 2005 and has been linked to 110 deaths.
"These results are strong and very competitive," said Rahul Singhvi, Novavax's chief executive.
Shares of Novavax fell 6 cents, or 2 percent, to $2.91.
Novavax has had a demo of the vaccine manufacturing process set up at its Rockville headquarters since May 1 but does not have a buyer.
There were 385 cases of bird flu in humans, leading to 243 deaths, from 2003 to June 19, according to the World Health Organization's most recent data. Outbreaks have mostly centered on Asia.
Many large multinational biotechs -- GlaxoSmithKline, Sanofi-Aventis, Novartis -- are working on bird flu vaccines in the United States and Western Europe under government contract, said Ken Trbovich, an analyst with RBC Capital Markets.
Novavax has partnered with GE Healthcare to reach the rest of the world by providing other countries a system to quickly mass-produce vaccines.
"If you truly believe a pandemic outbreak is likely, there is reason to believe foreign governments and the U.S. will clamp down and control the supply," Trbovich said. He added, "Other places in the world may have a lot of money, but no amount of money will get you vaccines in the case of a pandemic."
Traditionally, to create flu vaccines, drugmakers grow live virus strains in chicken eggs, which act as incubators. The virus is later killed and bottled into a vaccine. But eggs are a volatile medium, and a scarce supply essentially stops production.
Novavax's bird flu vaccine uses particles that mimic the size and shape of the virus, which trigger an immune response but lack the genetic material to replicate.
Because the particles are produced in more stable insect-cell cultures, yields are seven to 10 times higher than egg-based manufacturing, Novavax said. The vaccine can also be created within 10 to 12 weeks of identifying a pandemic strain -- half the time it takes to make egg-based vaccines.
GE is developing the production equipment, which is cheap to set up and run in case of a pandemic.
In December, Novavax studied low doses of its bird flu vaccine in a much smaller patient population. After tweaking the production process, the biotech was able to elicit a stronger immune response in this recent trial.
Novavax is seeking a governmental or pharmaceutical partner to finance the next set of human trials.
"We see no reason to invest additional money of our own into the pandemic vaccine when we can wait for a foreign government that needs this vaccine to put money in," Singhvi said.
Meanwhile, Novavax will be begin human tests of its seasonal influenza vaccine, using virus-like particles, in the fall. Currently all U.S. flu vaccines are egg-based.
"The pandemic area is difficult to monetize even if you successfully generate a contract," Trbovich said. "There are no reoccurring revenues. Moving a seasonal flu vaccine into clinical trials is their first real commercial opportunity."