U.S. human tests of swine flu vaccine begin

The University of Maryland’s Center for Vaccine Development is one of nine academic sites nationwide testing a vaccine to fight the pandemic. Since the outbreak this spring, the virus has claimed some 436 lives nationwide — including five in Maryland — and sickened as many as 1 million, according to estimates by the Centers for Disease Control and Prevention. Infectious disease experts fear the virus could mutate into a deadlier strain this fall, and researchers are in a mad dash to have a vaccine ready by the time the season hits.

The Baltimore Sun’s Kelly Brewington writes that nationwide, researchers will enroll 2,400 volunteers in trials that will test two vaccines in five population groups and at two different strengths. Investigators will also study the best time to give the vaccine: before, during or after the typical vaccination schedule for the seasonal flu.

UM’s portion of the nine-center vaccine trial will test two doses of a vaccine from manufacturer Sanofi Pasteur. Volunteers will receive the doses three weeks apart and at two strengths — either 15 micrograms or 30 micrograms. Along with 67 adults ages 18-64 who are slated to complete the first round of inoculations this week, 67 elderly volunteers ages 65 and older will receive their initial shots Wednesday through next Tuesday.

Researchers will follow up with volunteers eight days after the first shot for blood tests, which will show if people have developed antibodies that indicate they have an immune response to the virus. Then, volunteers will return two weeks later for another injection.

If all goes well with both groups, the vaccine will be tested in 260 children as soon as the end of next week, said Dr. Karen Kotloff, professor of pediatrics and medicine at the Center for Vaccine Development, and the principal investigator for the trial here. By then, researchers should have a good understanding of any reactions the vaccine could cause, she said.

“We have taken this under very careful consideration,” she said, adding this vaccine is very similar to the seasonal flu shot, which is not tested on people before it is rolled out every fall. “I don’t think there’s any scientific basis for being concerned that this vaccine would behave any differently from any other flu vaccine from a safety stand point.”

The vaccine will be tried in children as young as 6 months old. Children are among the five priority groups the CDC has identified should get the virus should there be a mass vaccination effort, since children have been more susceptible to this new flu strain. Medical experts think that older people may have been exposed to similar strains of the virus and may have some immune protection against it.

Kotloff said she has been impressed by the overwhelming response from volunteers. While researchers are still seeking people 65 and older to take part, they have so many young adult volunteers they had to use a lottery system to pick the final participants. Children, too, enrolled in large numbers - especially those with doctors for parents. “To me, that is very comforting,” Kotloff said. “These are people who have a very good understanding of influenza and influenza vaccine, they have weighed, in a very personal way, what the risk and benefits are and have decided to volunteer their children. That says a lot.”