Bacterial infections pose a major health risk in cystic fibrosis patents, which can lead to hospitalization and life-threatening health issues. As a result, the research community continues to focus on new therapies that effectively treat CF patients for common bacterial infections in the lungs while also facilitating patient compliance. A newly-released study reveals that researchers may have uncovered a new solution for developing a once-daily antibiotic that is effective at combating Pseudomonas aeruginosa — a common and serious infection in cystic fibrosis patients.
The new insight comes as a result of a clinical trial extension that tested liposomal amikacin for inhalation (Arikace) against twice daily tobramycin. When measuring results for CF participants in a forced expiratory volume in 1 second (FEV1) trial, positive gains were observed in patents who took the on the once-a-day antibiotic up to a year later, according to Dr. Diana Bilton of Imperial College London.
“In the patients who were on liposomal amikacin for 18 months — 6 months in the original trial and 12 months in the extension — we are seeing a sustained improvement in lung function,” Dr. Bilton said at the American Thoracic Society annual meeting.
Along with her colleagues, Dr. Bilton also noted that study participants who were treated on a long-term regimen with amikacin revealed continued reductions in P. aeruginosa colonies in the lungs. However, the reduction in bacteria appeared to wane through the course of treatment.
“There was a half-log reduction after 6 months, and we see a gradual wane of effectiveness out to 1 year, but certainly no increase in colonies from baseline,” Bilton said.
P. aeruginosa is a bacterial infection that can lead to chronic lung infection and severe long term lung damage in CF patients. While doctors usually treat patients with this infection with nebulized antibiotics, the new Arikace scheme could lead to effective, ongoing treatment of the infection while fostering patient adherence.
For Denis Hadjiliadis, MD, a professor at the University of Pennsylvania Health System in Pennsylvania, the real takeaway from the extension study was not so much the efficacy of Arikace, but rather the ability to administer the formula in a user-friendly regimen: “We are not seeing anything in this report that is unexpected,” he said. “The main benefit that liposomal amikacin has when compared to tobramycin is that the liposomal formula can be administered once a day.”
In spite of the positive results, Dr. Hadjiliadis suggests that more analysis is needed to determine the overall viability of Arikace in the CF drug market: “where amikacin will fit in the treatment of CF is uncertain,” he said. “I think it will depend on the cost of the drug and whether the convenience of once-daily treatment will outweigh increased costs. However, all these drugs are expensive, so I don’t think that amikacin — if it is approved by the FDA — will be that much more expensive than tobramycin.”