Vaccination of patients with mild and severe asthma with a 2009 pandemic H1N1 influenza virus vaccine

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MADISON, Wis. ? Older people with severe asthma may need a double dose of H1N1 vaccine for adequate protection, according to a study headed by University of Wisconsin School of Medicine and Public Health (SMPH) scientists.

Dr. William Busse, professor of medicine in the allergy and asthma section of SMPH, directed the first multicenter clinical trial on adequate and safe H1N1 vaccine dosages for people with asthma. During the 2009 pandemic, people with asthma were hospitalized at a rate four to five times higher than otherwise healthy adults.

The findings are published in the December issue of the Journal of Allergy and Clinical Immunology.

The study looked at the vaccine?s safety for asthmatics and its ability to induce an immune response with two H1N1 doses (15mcg and 30mcg) for 390 men and women with mild to severe asthma. A second dose was administered three weeks after the first. The research found that both doses, including the standard 15mcg dose, were adequate and safe for people with mild to moderate asthma. However, only 78 percent of older people with severe asthma were adequately immunized with the conventional dose compared to 94 percent with the higher dose.

?People aged 60 and older in particular were not adequately immunized against H1N1 with the lower, conventional vaccine dosage,? said Busse. ?That suggests older adults with severe asthma may need doses higher than the average person.?

The current high-dose seasonal vaccine, formulated to protect against H1N1, has an adequate dosage to protect people with severe asthma.

The study also found that the second vaccination given three weeks after the first did not provide further protection against H1N1. In fact, the findings also note that the immune protection dropped after the second vaccination for older participants with mild to moderate asthma. Busse says that could indicate that a higher dose would also be appropriate for them.

The study is co-sponsored by the National Institute of Allergy and Infectious Diseases and the National Heart, Lung and Blood Institute.

In addition to the University of Wisconsin, six other research centers participated in the clinical trials including the Cleveland Clinic, Emory University, University of Pittsburgh, University of Virginia, Wake Forest University and Washington University.

http://www.rrstar.com/healthyrockfo...ople-with-severe-asthma-need-higher-H1N1-dose

 

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Re: People with severe asthma need higher H1N1 dose

Re: People with severe asthma need higher H1N1 dose

Vaccination of patients with mild and severe asthma with a 2009 pandemic H1N1 influenza virus vaccine


The Journal of Allergy and Clinical Immunology

Received 27 September 2010; received in revised form 10 November 2010; accepted 12 November 2010. published online 10 December 2010.


Background

Asthma was the most common comorbidity of patients hospitalized with 2009 H1N1 influenza.
Objective

We sought to assess the immunogenicity and safety of an unadjuvanted, inactivated 2009 H1N1 vaccine in patients with severe versus mild-to-moderate asthma.
Methods

We conducted an open-label study involving 390 participants (age, 12-79 years) enrolled in October-November 2009. Severe asthma was defined as need for 880 μg/d or more of inhaled fluticasone equivalent, systemic corticosteroids, or both. Within each severity group, participants were randomized to receive intramuscularly 15 or 30 μg of 2009 H1N1 vaccine twice 21 days apart. Immunogenicity end points were seroprotection (hemagglutination inhibition assay titer ≥40) and seroconversion (4-fold or greater titer increase). Safety was assessed through local and systemic reactogenicity, asthma exacerbations, and pulmonary function.
Results

In patients with mild-to-moderate asthma (n = 217), the 2009 H1N1 vaccine provided equal seroprotection 21 days after the first immunization at the 15-μg (90.6%; 95% CI, 83.5% to 95.4%) and 30-μg (95.3%; 95% CI, 89.4% to 98.5%) doses. In patients with severe asthma (n = 173), seroprotection 21 days after the first immunization was 77.9% (95% CI, 67.7% to 86.1%) and 94.1% (95% CI, 86.8% to 98.1%) at the 15- and 30-μg doses, respectively (P = .004). The second vaccination did not provide further increases in seroprotection. Participants with severe asthma who are older than 60 years showed the lowest seroprotection (44.4% at day 21) with the 15-μg dose but had adequate seroprotection with 30 μg. The 2 dose groups did not differ in seroconversion rates. There were no safety concerns.
Conclusion

Monovalent inactivated 2009 H1N1 pandemic influenza vaccine was safe and provided overall seroprotection as a surrogate of efficacy. In patients older than 60 years with severe asthma, a 30-μg dose might be more appropriate.

http://www.jacionline.org/article/S0091-6749(10)01764-1/abstract