Azithromycin Use Tied to Fewer Exacerbations in Asthma Patients

Exacerbations were eliminated in about one-third of adult asthma patients treated prophylactically with the macrolide azithromycin, a researcher reported.

In the real-world study presented at CHEST 2021, the American College of Chest Physicians annual meeting held online, Hanan Ajay, a fifth-year medical student at the University of Liverpool in England said that of the 34 patients included in the observation study, only one did not have a reduction in infections by at least 50% compared with the historical average of 6.44 infections a year.

Overall, the annual average for patients while on azithromycin was 1.47 infections a year (P<0.01), and 12 of the patients in the study had zero infections while on azithromycin. "Azithromycin is a safe and effective prophylactic drug in reducing exacerbations in this real-world study," Ajay said.

The research team set out to test how the British Thoracic Society recommendations for the long-term use of macrolides to reduce the exacerbation rate in adults with asthma played out in the real world. "The macrolide of choice within the United Kingdom is azithromycin," Ajay noted.

The study had four objectives, and results were as follows:

• Determine if use of azithromycin in the real world reduced the number of respiratory tract infections -- it did

• Determine if the adverse events seen in clinical studies of the approach manifested in the real world – they did, although at a lower rate than seen in clinical trials

• Determine the reasons for discontinuation of azithromycin -- 13 patients discontinued use in the study: four due to gastrointestinal adverse events, two due to hearing problems, and seven for perceived ineffectiveness

• Determine if long-term use of azithromycin improved lung function -- no impact on lung function was seen

Asked for his perspectives, Steven Louie, MD, of Florida Allergy & Asthma Associates in Atlantis, said: "I have used azithromycin as a prophylactic treatment in my patients from time to time, but it is not standard of care."

He explained to MedPage Today that treatment with azithromycin comes in and out of favor, but the macrolide class of antibiotics is known to reduce inflammation and can be helpful in preventing exacerbations in asthma.

For the study, Ajay and colleagues excluded patients with non-tuberculosis mycobacterium, chronic obstructive pulmonary disease, bronchiectasis, those being treated with other long-term antibiotics or with monoclonal antibodies, and those taking nebulized antibiotics.

All patients in the study had asthma and were over age 18 (median 58), nine were men, and 25 were women. Patients received 250 mg tablets of azithromycin three times a week, and mean duration of treatment was about 40 months. Seven of the patients included in the study were considered to be immunosuppressed. Average body mass index was 31.7. Eight of the patients in the study were current smokers; nine were ex-smokers, and 17 were never-smokers.

Study limitations, Ajay said, included the small sample size and that there could have been recall bias among the patients in citing historical infections.

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