Similar anti-asthmatic activity of budesonide via Turbuhaler® and fluticasone via Diskus®

The study was published in the most recent issue of Clinical Therapeutics and has been run in several countries in Europe and in South Africa, with main investigator Dr Piotr Kuna in Lodz, Poland. It shows that patients with moderate asthma needed the same median dose of the two treatments, 400 µg, to gain control of their asthma disease. This result contrasts to several earlier studies where a double dose of Pulmicort Turbuhaler has been claimed necessary for obtaining the same asthma control. However, there are considerably differences in design between the studies, which may explain the different outcomes.

”In fact, comparing the anti-asthmatic activity of inhaled steroids is one of the most challenging tasks in asthma therapy. Only extremely carefully designed studies will reveal a true dose relation between two treatments. There are even several studies comparing different doses of the same steroid, which do not show any clinically differences”, Dr Kuna said.

The study by Dr Kuna and co-workers fulfilled all established standards of high quality, i.e. it was randomised and double blind, using double-dummies of the treatments. Compliance was checked and was equally high for the two treatments and the patients also equally preferred them. Before the comparison of the two study drugs all patients received another inhaled steroid (BDP) via a pressurized meter dose inhaler. The patients had moderately severe asthma and it was thoroughly checked that only patients gaining control of their asthma with a very high dose of BDP (2000 µg) entered the study. The actual dose comparison was performed by reducing the dose of the two drugs at five weeks intervals, starting at 800 µg/day, down to 400 and then 200 µg, but only if stringent criteria of asthma control were fulfilled. The minimal effective dose was defined as the dose level for each patient before loss of asthma control.

Of importance was also that the comparison was started at the same nominal doses of Pulmicort Turbuhaler and Flixotide Diskus. In this study even the same strengths of each inhaler (100 µg) was used.

The result is in agreement with an earlier study with a similar dose-reduction design comparing Pulmicort Turbuhaler with Flixotide in another dry powder device, Diskhaler™, in asthmatic children. In this study the minimal effective doses ended up at 212 µg for Pulmicort Turbuhaler and 198 µg for Flixotide Diskhaler. In the present study by Kuna and co-workers in adults the corresponding doses for Pulmicort Turbuhaler and for Flixotide Diskus were 463 µg and 376 µg, respectively. These small differences between the drugs were not statistically significant.

A possible explanation for the result is that Diskus and Diskhaler deliver much less drugs to the lungs than Turbuhaler. Diskhaler and the newer Diskus both deliver around 13-16% of the nominal dose of fluticasone to the lungs, while Turbuhaler delivers around 30-35% of budesonide. So although fluticasone as a molecule may be more potent at the steroid receptor this will be offset by an at least double deposition of budesonide in the lungs.

”With this new study it is confirmed that the two drugs delivered via their respective dry powder inhalers excert similar anti-asthmatic activity and similar low doses of the two drugs can be used. This will be of great importance not least for the costs of these asthma treatments, as in most countries budesonide Turbuhaler is considerably cheaper microgram for microgram”, Dr Kuna concluded.

Further enquires to:

Wendy Morris
CPR Worldwide, London
Mobile: +44 79 41 86 17 89
E-mail: w.morris@cprworldwide.com

Cecilia Svensson
AstraZeneca, Lund, Sweden
Mobile: +46 70 537 77 72
E-mail: cecilia.svensson@astrazeneca.com





AstraZeneca is a major international healthcare business engaged in the research, development, manufacture and marketing of prescription pharmaceuticals and the supply of healthcare services. It is one of the top five pharmaceutical companies in the world with healthcare sales of over $17.8 billion and leading positions in sales of gastrointestinal, oncology, cardiovascular, neuroscience and respiratory products. AstraZeneca is listed in the Dow Jones Sustainability Index (Global and European) as well as the FTSE4Good Index.

Pulmicort® and Turbuhaler® are registered trademarks, property of the AstraZeneca group of companies. Flixotide™, Diskus™ and Diskhaler™ are registered trademarks, property of the GSK group of companies.


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