Antibiotic Combination Seen to Effectively Treat Chronic CF Lung Infections

A combination therapy with inhaled Bramitob (tobramycin) and Colistin (colistimethate sodium) improves lung function and respiratory symptoms in cystic fibrosis (CF) patients, according to a study published in the journal Cellular Physiology and Biochemistry.

Chronic lung infections are common and difficult to treat in CF patients. Pseudomonas aeruginosa is one of the most common infectious agents in CF patients, and although inhaled antibiotic therapy shortly after infection can be very effective in killing the bacteria, once the lung infection becomes chronic, antibiotics do not always work well.

Researchers, led by Dr. Uwe Mellies at University Children’s Hospital Essen in Germany, conducted an exploratory study to assess the efficacy of Bramitob (known as Bethkis in the U.S.) combined with Colistin on lung function in CF.

They recruited 41 CF patients, ages 6 to 50, who have had chronic P. aeruginosa infections for six months. Participants received Bramitob inhaled twice a day at 12-hour intervals for 28 days, followed by Colistin inhaled twice a day for 28 days. This cycle was repeated for six months.

Results showed that both mucus production and coughing decreased by 39% in patients treated sequentially with Bramitob and Colistin. In addition, FEV₁ absolute (the volume of air that can forcibly be blown out in one second after full inspiration; a measure of lung function) increased by 4.9%, and FEV₁ relative to baseline increased by 9.1%.

The efficacy of the therapy was rated “excellent” or “good” by clinicians in 80.5% of the patients.

The authors of the study, “Sequential Inhalational Tobramycin-Colistin-Combination in CF-Patients with Chronic P. Aeruginosa Colonization – an Observational Study,” concluded that treatment with sequentially combined inhaled antibiotics is very well-tolerated and may have a beneficial effect on lung function and respiratory symptoms.

Bramitob/Bethkis, or tobramycin, is an antibiotic derived from the bacteria Streptomyces tenebrarius. It is used to treat various types of infections and is especially effective against Pseudomonas species. Because it does not pass the gastrointestinal tract, it is used as an inhaled medicine.

Colistin is an antibiotic produced by certain strains of the bacteria Paenibacillus polymyxa. It is not widely used because of its toxicity in the kidneys. However, it is very efficient, and resistance to Colistin is rare. It is used as a last-resort antibiotic for multi-drug resistant P. aeruginosa infections.