Dry Powder Inhaled Antibiotics Safe, Effective for Bronchiectasis, Study Suggests

Dry Powder Inhaled Antibiotics Safe, Effective for Bronchiectasis, Study Suggests

Inhaled antibiotics in dry powder formulations are safe and effective in people with bronchiectasis, a study suggests.

The study, “Inhaled Dry Powder Antibiotics in Patients with Non-Cystic Fibrosis Bronchiectasis: Efficacy and Safety in a Real-Life Study,” was published in the Journal of Clinical Medicine.

Antibiotics are medications that kill bacteria, including those which can cause lung infections. In such cases, delivering the medicine via inhalation can be useful, as it gets the antibiotic directly to the site of infection.

Dry powder inhaled antibiotics (DPIA) differ from nebulized antibiotics, in which a liquid medicine is converted into a mist, which is then inhaled.

DPIA may hold several advantages over nebulized antibiotics, as their devices are typically smaller, more transportable, easier to clean, and may enable more of the medication to reaches the lung. However, some research has suggested that DPIA may cause more adverse effects.

Researchers in Spain analyzed clinical information from 164 people with bronchiectasis (mean age of 65.7 years). Data were collected from 33 centers across the country. Chronic obstructive pulmonary disease (COPD) was observed in 37% and asthma in 20.6% of the participants. Nearly all analyzed patients were also treated with other medicines besides antibiotics, such as bronchodilators and steroids.

Regarding DPIA treatment, 141 patients (86%) were treated with colistin and 23 (14%) with tobramycin. “These are the only two [DPIAs] currently on the market,” the researchers wrote.

Most (65.1%) had previously been treated with other types of inhaled antibiotics.

The most common reason for treatment, in 86% of those analyzed, was chronic lung infection with Pseudomonas aeruginosa, which is common in bronchiectasis.

To assess efficacy, the scientists compared clinical data from the year prior to treatment with the year after. Following DPIA, there was a significant reduction in the average number of yearly exacerbations — both severe (0.73 vs. 0.33) and non-severe (1.9 vs. 1.77). Likewise, the team found a significant reduction in the number of exacerbators, defined as individuals with at least two exacerbations or at least one hospitalization in the previous year (45% vs. 20%).

DPIA treatment significantly reduced the number of people with lung infections due to P. aeruginosa (52% vs. 81%) and other bacteria (10% vs. 29.4%), while no difference was found in fungal infections. In addition, DPIA treatment significantly decreased the percentage of patients producing excessive amounts of sputum (19% vs. 31.6%).

Overall, 54.2% of those analyzed experienced at least one adverse effect, and 24.4% had to interrupt treatment. The most common adverse effect was cough (40.8%), which accounted for 84% of treatment interruptions.

“Our study suggests that DPIA are clinically efficacious and safe for treating bronchiectasis patients,” the researchers wrote.

Statistical modeling indicated that coughs, as an adverse effect, were more likely to develop in people with COPD, those with a previous history of coughing, and people who reported more difficulty handling the inhalation device. These factors were also significantly indicative of treatment interruption.

“This suggests that any prescription of these drugs must be complemented by close monitoring of patients with previous airflow obstruction due to COPD or usual cough,” the investigators wrote. “It is essential to instruct patients about correct use of the device and give them information about how to handle any coughing.”

Generally, the two types of antibiotics analyzed were similar in terms of efficacy and adverse effects. Notable exceptions were that, compared with those given tobramycin, significantly fewer patients on colistin had a treatment interruption (20% vs. 27%), reported difficulty using the device, or had P. aeruginosa that developed antibiotic resistance (3% vs. 22%).

According to the researchers, the difference in interruption rates could be due to dosing — colistin typically requires fewer doses than tobramycin. They said that, since colistin was used by more people in the study, the comparison with tobramycin should be interpreted with caution. They added that not having a control group was another limitation. As such, more research is needed to further clarify the safety and efficacy of DPIAs.