Aradigm initiates dosing in Phase 2b trial of inhaled liposomal ciprofloxacin formulations in BE patients

Aradigm Corporation (OTCBB:ARDM) (the “Company”) today announced that it dosed the first patient in the U.S. as part of its ORBIT-1 (Once-daily Respiratory Bronchiectasis Inhalation Treatment) trial, an international, randomized, double-blind, placebo-controlled Phase 2b study designed to evaluate the Company's inhaled liposomal ciprofloxacin (ARD-3100) in patients with non-cystic fibrosis bronchiectasis (BE) under a U.S. IND. This orphan disease indication is a chronic, severe respiratory disease and there are currently no approved treatments for this disease in the U.S.

"The initiation of our ORBIT-1 trial, the second Phase 2b trial with our once-a-day inhaled liposomal ciprofloxacin formulations in BE patients, is another important milestone in developing new therapies for this underserved patient population. We have been fortunate to assemble an excellent international clinical investigators team for this trial. We expect to be able to report the results of this study in the second half of 2010," said Dr. Igor Gonda, the Company's CEO and President.

The ORBIT-1 trial, a Phase 2b study, will randomize 96 patients, who will receive for four weeks either one of two different once-daily inhaled doses (100 or 150 mg ciprofloxacin delivered by inhalation as 2 or 3 mL of liposomal dispersion, respectively) or once-daily inhaled placebo. The primary efficacy endpoint will be a standard measure of antibacterial activity - the change from baseline in sputum Pseudomonas aeruginosa colony forming units (CFUs). Secondary endpoints will include quality of life measurements and improvement of outcomes with respect to exacerbations. Lung function changes will be monitored for safety.

In a previously conducted Phase 2a study of ARD-3100 in BE patients, 150 mg or 300 mg ciprofloxacin delivered once-a-day by inhalation as 3 or 6 mL of liposomal dispersion, respectively, were administered in an open-label study for four weeks. The primary efficacy endpoint was the change from baseline to end of treatment in sputum Pseudomonas aeruginosa CFUs. Both doses of inhaled liposomal ciprofloxacin in the evaluable patient population demonstrated significant mean decreases against baseline in the Pseudomonas aeruginosa CFU of 3.5 log (p<0.001) and 4.0 log (p<0.001) units, respectively. With regard to safety, there were no statistically significant changes in lung function at the end of treatment as measured by the normalized forced expiratory volume in one second (FEV₁ % predicted). Inhaled liposomal ciprofloxacin was well tolerated.

The Company previously announced the initiation of a six-month Phase 2b study in BE patients in Australia and New Zealand, the ORBIT-2 trial, using another inhaled ciprofloxacin formulation (ARD-3150) that has a different drug release profile from ARD-3100. The results from each of these trials will produce an extensive data base of information from which to select the optimum product and the most appropriate endpoints to test in Phase 3.