Research
December 16, 2010
H1N1 vaccine safe for asthma patients
A study of the 2009 H1N1 influenza vaccine in adolescents and adults with asthma showed that a single dose of the vaccine was safe and induced a strong immune response. Individuals over age 60 with severe asthma may require a larger vaccine dose, however. The study appears online in the Journal of Allergy and Clinical Immunology.
The Emory-Children’s Center, jointly operated by Emory and Children’s Healthcare of Atlanta, was one of seven participating sites in the study. In partnership with Emory, Children’s recently designated immunology and vaccines as one of eight priority research focus areas for the pediatric healthcare system.
The study of 390 people aged 12 to 79 was conducted at Severe Asthma Research Program (SARP) sites sponsored by the National Heart, Lung, and Blood Institute of the National Institutes of Health (NIH). It was co-sponsored by the National Institute of Allergy and Infectious Diseases of the NIH.
“It was very important that we find the optimal dose of H1N1 flu vaccine that could be given safely to our asthma patients,” says Anne Fitzpatrick, principal investigator of the Emory trial. Fitzpatrick leads the SARP program at the Emory-Children’s Center.
People with severe asthma are at greater risk for complications following flu infection. They also often take high doses of glucocorticoid medications that can suppress their immune systems, putting them at even greater risk for infection and serious disease.
The H1N1 vaccine is one component of the seasonal influenza vaccine currently being distributed for the 2010-2011 influenza season.
The vaccine study divided participants into two groups: those with mild or moderate asthma and those with severe asthma. Half of the participants in each group received a 15-microgram dose of injected vaccine, and the other half received a 30-microgram dose. Three weeks later, each participant received a second dose of the same amount. The vaccine, manufactured by Novartis, contained inactivated 2009 H1N1 influenza virus and therefore could not cause influenza infection.
Three weeks after each injection, investigators measured blood antibody levels of 2009 H1N1 influenza virus to assess the immune response. In patients with mild to moderate asthma, and in most patients with severe asthma, a single 15-microgram dose induced an adequate immune response to be protective. Participants older than 60 with severe asthma had a diminished immune response to the 15-microgram dose, but adequate responses with the 30-microgram dose.
Participants were monitored for any side effects or for asthma attacks. The vaccine was well tolerated and did not worsen asthma in participants.
