Bayer is conducting two Phase 3 clinical trials evaluating ciprofloxacin Dry Powder for Inhalation (ciprofloxacin DPI) as a treatment for non-cystic fibrosis (non-CF) bronchiectasis, and preliminary data show promising results. The RESPIRE trial program is the largest yet conducted in this patient population, according to the company.
The design and details of the two trials, RESPIRE 1 (NCT01764841) and RESPIRE 2 (NCT02106832), were recently published in a report titled “The RESPIRE trials: Two phase III, randomized, multicentre, placebo-controlled trials of Ciprofloxacin Dry Powder for Inhalation (Ciprofloxacin DPI) in non-cystic fibrosis bronchiectasis” in the journal Contemporary Clinical Trials.
Ciprofloxacin DPI is an experimental therapy designed to reduce exacerbations in non-CF bronchiectasis patients with bacterial respiratory pathogens. The therapy consists of the administration of the antibiotic ciprofloxacin via a powder solution inhaled from a handheld device developed by Novartis — the PulmoSphere technology.
“The RESPIRE trials will determine the efficacy and safety of Ciprofloxacin DPI,” researchers wrote. “The strict entry criteria and stratified randomization, the inclusion of two treatment regimens and a stringent definition of exacerbation should clarify the patient population best positioned to benefit from long-term inhaled antibiotic therapy.”
The two RESPIRE trials have the same design, but they differ slightly in their analysis plans according to the agreement set with two regulatory organizations — the U.S. Food and Drug Administration (FDA), and the European Medicines Agency (EMA) and other agencies.
The RESPIRE 1 trial evaluated whether treatment with ciprofloxacin DPI could be used as a long-term, intermittent therapy in non-CF bronchiectasis from 14 different countries. The study enrolled 416 patients.
Patients were treated with ciprofloxacin DPI (32.5 mg twice daily) for 28 days, and then were 28 days off treatment, or 14 days of treatment followed by 14 days off treatment, or a placebo treatment, during a 48-week period.
Preliminary results have shown that the time to first pulmonary exacerbation of bronchiectasis — the trial’s primary outcome in line with FDA requirements — within 48 weeks in patients receiving the ciprofloxacin DPI 28 day on/off regimen was 336 days (141 patients analyzed), compared to 186 days in the placebo group (138 patients analyzed).
The trial is still ongoing and further data analyses need to be performed, but so far results suggest that treatment with ciprofloxacin DPI may help prolong the time to first exacerbation on non-CF bronchiectasis patients, compared to placebo.
The RESPIRE 2 study had a similar design to that of RESPIRE 1 and was completed in 2016. The trial included 519 adult patients with non-CF bronchiectasis and stable lung function. The primary outcome of this trial is the frequency of exacerbations during the 48-week study, in line with EMA requirements. Results of the RESPIRE 2 study have not yet been released.