January 1, 2009 — Some patients with severe asthma who also have allergic sensitivity to certain
fungi enjoy great improvements in their quality of life and on other measures
after taking an antifungal drug, according to new research from The University
of Manchester in England.
The findings were reported in the first issue
for January of the American Thoracic Society’s American Journal of Respiratory
and Critical Care Medicine.
“We knew that many people with severe asthma
are sensitized to several airborne fungi which can worsen asthma without overt
clinical signs. The question was: does antifungal therapy provide any clinical
benefit,” said David Denning, F.R.C.P., F.R.C.Path., professor of medicine and
medical mycology at The University of Manchester and lead investigator of the
In 2006, the most recent year for which official statistics are
available, there were more than 16 million adults with self-reported asthma in
the U.S.; about 20 percent of them have severe asthma.
A small number of
severe asthmatics—about one percent— are known to have a syndrome called
allergic bronchopulmonary aspergillosis, an extreme allergy to Aspergillus
fumigatus fungus that is associated with the long-term colonization of their
respiratory tracts with the fungus. But many more — 20 to 50 percent— are
sensitized to a variety of fungi without showing overt clinical signs or
demonstrable colonization. It is these patients with severe asthma with fungal
sensitization, or “SAFS”, as the researchers named the syndrome, who are most
likely to enjoy marked improvement with the antifungal therapy.
prospective double-blind study, 58 patients with severe asthma and allergic
sensitivity to at least one of seven different common fungi (confirmed by a
skin-prick test and/or an IgE blood test for the study) were randomized to
receive either an oral dose of itraconazole (200mg twice a day) or a placebo.
After 32 weeks of treatment, 18 of the 29 patients (62 percent) who were
randomized to receive the drug experienced significant improvements on their
Asthma Quality of Life Questionnaires, and in runny nose and morning lung
function. However, 11 of the patients who received the drug left the trial
before completion, some citing side effects that included nausea, breathlessness
and muscle weakness. Unfortunately, four months after stopping antifungal
treatment, symptoms had returned.
“This study indicates that fungal
allergy is important in some patients with severe asthma, and that oral
antifungal therapy is worth trying in difficult-to-treat patients. Clearly
itraconazole will not suit everyone and is not always helpful, but when it is
the effect is dramatic,” said Dr. Denning. “These findings open the door to a
new means of helping patients with severe asthma, and raise intriguing questions
related to fungal allergy and asthma.”
John Heffner, M.D., past president
of the ATS, reflected that the recent Severe Asthma Research Program report
describes severe asthma as a entirely different form of the disease. “Patients
with severe asthma may have unique triggers for bronchospasm, which remain
unidentified. This study suggests that colonization with fungal species may
generate immunologic responses in patients with asthma that perpetuate airway
inflammation and blunt the effectiveness of drug therapy. One can’t help but
wonder if antifungal therapy would benefit all severe asthmatics regardless of
sensitivity to fungi.”
A press release provided by the American Thoracic Society — the world’s leading medical association
dedicated to advancing pulmonary, critical care and sleep medicine.