The drug development news highlighted at this year's North American CF Conference focused mainly on clinical trials sponsored by the CF Foundation.

In particular, results from two clinical trials took center stage during key plenary sessions of the conference. The studies focused on the best way to treat Pseudomonas aeruginosa, a type of bacteria that often lives in the lungs of people with CF and causes lung infections.

Previous studies showed that the antibiotic azithromycin improved lung function and reduced exacerbations in people with CF who are chronically infected with Pseudomonas aeruginosa. Using azithromycin has become a standard of care across the United States for CF patients who are chronically infected with P. aeruginosa.

The most recent studies presented at NACFC were the Azithromycin Follow-up Trial, known as MAC 004, and the Early Pseudomonas Infection Control trial, or EPIC.

The MAC 004 trial looked at using the antibiotic azithromycin in people with CF age six to 18 who are not infected with Pseudomonas aeruginosa.

“The types of infection that people with CF get vary with age,” explained Lisa Saiman, M.D., professor of clinical pediatrics at Columbia University and a lead investigator of the MAC 004 trial. “While Pseudomonas aeruginosa can occur in very young infants, it actually increases in frequency until the age of about 25 when approximately 80 percent of people with CF are infected with Pseudomonas aeruginosa.”

It is important for researchers to learn more about how to manage children with CF who are not infected with P. aeruginosa.

New data from the MAC 004 trial presented at NACFC showed that azithromycin reduced the number of lung exacerbations in people with CF by approximately 50 percent. It also led to an improvement in weight gain. Azithromycin may prove to be an important treatment for children who are having frequent lung exacerbations.

The EPIC trial was also highlighted during a plenary session. This trial examined how often antibiotics should be used to try to eliminate Pseudomonas aeruginosa when it is first detected in people with CF age one to 12 years.

The study looked at two different approaches.

• The first approach focused on treating CF patients with antibiotics only if they tested positive for Pseudomonas aeruginosa.
• The second approach provided CF patients with antibiotics regularly (every three months) in hopes of better clearing and preventing a recurrence of Pseudomonas aeruginosa.

“The trial showed that both of the approaches worked,” said Bonnie Ramsey, M.D., professor of pediatrics at the University of Washington and a principal investigator of the EPIC trial.

“Since the data was just released at this conference, we're analyzing the results. But it appears that the preventative approach does no better than treating CF patients only when Pseudomonas aeruginosa is detected.”