Chinchilli said the sample size of 255 patients with mild asthma from five participating medical centers is sufficient for the conclusions drawn from the data. He said the data are of the highest quality, due to extremely rigorous research methods employed in all aspects of the 26-week randomized, double-blind, placebo-controlled study.
Clinical coordinators at each of the study locations were able to enter data over the Internet using an online form. The data were then verified by data managers at Hershey. In addition to keeping a daily record of symptoms, 10 to 16 pages of data were produced for all 255 patients on each of 12 hospital visits.
After a 6-week evaluation period, patients were randomized to receive either the inhaled beta-agonist, albuterol, two puffs four times a day, or an identical-appearing placebo inhaler for 16 weeks. Patients in both groups were permitted to take additional albuterol, when needed, for relief of asthma symptoms. During a final four-week withdrawal period, all patients received only as-needed albuterol.
The study showed that even though the average use of albuterol was five times higher in the regular use group than in the as-needed group, there were no significant differences between the two groups in measures of lung function, asthma symptoms, or quality of life that could be attributed to the treatment. Although a few differences between the two groups could be attributed to the treatment, the effects were small and deemed to be clinically unimportant.
Asthma Clinical Research Network (ACRN) was created in 1993 by the NHLBI
as a five-year program to expedite design and implementation of clinical
trials on approaches to managing asthma. The albuterol and placebo for the
beta-agonist study were donated by Schering-Plough, headquartered in Kenil
Contact: Gail Brown