Bronchitol–Pulmozyme Combo Better Than Pulmozyme Alone to Clear Kids’ Lungs
Note: This story was updated Nov. 18, 2021, to correct information about Pulmozyme’s administration method.
Bronchitol (mannitol) plus Pulmozyme (dornase alfa) is better than Pulmozyme alone to help loosen mucus in the lungs in children with cystic fibrosis (CF), and this seems to translate into better lung function.
The study with that finding, “Comparison of inhaled mannitol/dornase alfa combination and daily dornase alfa alone in children with cystic fibrosis,” was published in the journal Pediatric Pulmonology by a team of researchers in Turkey.
People with CF build up a thick mucus in the lungs that can block airways and make it hard to breathe. There are several medications, called mucolytics, used to clear mucus from the airways. Bronchitol, available as a dry powder for inhalation, is one such medication and it works by drawing water from tissues, consequently moistening and thinning the sticky mucus.
“The dry powder formulation makes it easier and faster to use, without requiring a nebulizer,” the researchers wrote.
Previous trials in patients with CF showed that Bronchitol, marketed by Pharmaxis, given twice daily for up to 24 weeks (six months) can improve lung function and reduce exacerbations (a worsening of symptoms) compared with a placebo.
Now, researchers studied the long-term effects of adding Bronchitol to the therapeutic routine of children with CF who take 2.5 mg of Pulmozyme daily. Pulmozyme, marketed by Genentech, works by breaking down DNA in mucus, making it less viscous (sticky). Unlike Bronchitol, it usually is taken via inhalation of an aerosol mist produced by a compressed air-driven nebulizer or an approved nebulizer system.
The researchers looked back at the medical records of children ages 6 to 18 years treated from January 2017 to July 2020 at Ihsan Dogramaci Children’s Hospital in Ankara, Turkey.
Fifteen children (seven boys, eight girls), with a median age of 15.5 years, received treatment with both Bronchitol and Pulmozyme. Bronchitol was given at a dose of 400 mg, twice per day, 15 minutes after treatment with a bronchodilator to relax the airways, for a median of 18 months (ranging from three to 42 months).
Eighteen children (eight boys, 10 girls), with a median age of 14.9, received Pulmozyme only and were used as the control group.
Improvements in FEV1 — forced expiratory volume in one second, a measure of lung capacity that looks at the volume of a breath — over a three-month or a one-year period were greater in the group of children who took Bronchitol plus Pulmozyme than in controls.
When researchers looked at the results of other spirometry tests — measuring how much air one can breathe out in one forced breath — they also saw statistically significant improvements in the group of children who took Bronchitol plus Pulmozyme compared with controls.
Other measures of lung function, such as the frequency of lung exacerbations, did not differ between the two groups.
“The lack of a difference in pulmonary exacerbation frequencies between the groups may be explained by the continuation of all the current treatments, including dornase alfa [Pulmozyme] and inhaled antibiotics, and doing physiotherapy to help reduce pulmonary exacerbations,” the researchers wrote.
Moreover, there were no differences in the types of bacteria growing in the lungs of children who took Bronchitol plus Pulmozyme versus controls.
Eight children reported cough, three shortness of breath, two hemoptysis (coughing up of blood), and one patient experienced nausea as side effects of Bronchitol. Six of the initial 21 children who received Bronchitol stopped the treatment within one year (two patients stopped after one year), with the main reasons being shortness of breath and cough.
“The combination of mannitol and dornase alfa may be more useful than dornase alfa alone,” the researchers concluded, adding that while cough and shortness of breath may limit the use of Bronchitol in some children, it was found to be generally safe.
The team noted, however, that “the results of the present study have to be confirmed by larger-scale, longitudinal studies.”
Bronchitol is approved for use in children ages 6 and older in Russia and Australia. In the U.S., in countries of the European Union, and several other countries, it is approved for adults only.