Cystic Fibrosis Foundation Therapeutics (CFFT), the nonprofit drug development affiliate of the Cystic Fibrosis Foundation, announced the results of a new treatment approach for pulmonary dysfunction in people with cystic fibrosis (CF). Azithromycin (part of the macrolide antibiotic family and marketed by Pfizer Inc as Zithromax) is a drug currently used to treat common bacterial infections, such as pneumonia and ear infections, and has been proven effective in improving the lung function of people with CF chronically infected with Pseudomonas aeruginosa (pseudomonas). Pseudomonas is the most common cause of respiratory infection in people with CF and is tenacious in nature, causing chronic infection and inflammation.

The results of the trial showed that patients who took azithromycin experienced: 1) an average six percent improvement in lung function based on forced expiratory volume; 2) a nearly 50 percent decrease in days spent in the hospital for the treatment of pulmonary exacerbations; and 3) weight gain, which is a positive effect for people with CF. Mild side effects included nausea, diarrhea and wheezing. In nearly all patients, these symptoms were mild and did not lead to the drug being stopped or the dose of the drug being reduced.

The double-blind, placebo-controlled trial of azithromycin was conducted over a six-month period and included 185 patients with CF from 23 CF Foundation-accredited care centers around the country. Future studies are planned to assess the mechanism of action in the lungs and long-term benefits and risks.

Pfizer was instrumental in this trial by providing the study drug and the placebo and by sharing their already established data on azithromycin use to treat other diseases and indications. In addition, Pfizer played a valuable role in consulting on the study design and dosage recommendations.

Azithromycin has been commercially available for 10 years and is known to be safe with minimal side effects. The regimen in the trial will be a relatively simple addition to the medical routine practiced by people with CF: it consists of taking one to two pills (based on body weight), three times a week. The trial also showed that this drug was well tolerated in people with CF over the 24-week trial period. The hope is that CF patients can continue this treatment indefinitely.

The development of azithromycin as a treatment for CF reflects the on-going efforts of the CF Foundation to encourage researchers, universities and private biopharmaceutical firms to develop new treatments and medications for people with CF. The long-term goal of the CF Foundation is to cure CF by correcting the basic molecular and genetic defect. In the meantime, the CF Foundation continues to fund and encourage the development of new and more effective treatments to help control the disease and improve the overall quality of life for people with CF.

The results of this trial build upon earlier studies of azithromycin in people with CF conducted in the U.K. and Australia. This trial was the definitive study in that it was the largest and most rigorous in its design.