Liposomal delivery boosts CF drug efficacy in study

The novel inhalable formulation, which is being assessed at sites in Australia and New Zealand, is delivered using Aradigm's liposome encapsulation technology that allows for the slow release of the active drug when the particles are deposited in the respiratory tract. At present, commercially available formulations of ciprofloxacin are delivered either orally or intravenously in response to acute exacerbations of the various lung infections commonly associated with CF. Aradigm's candidate is designed to be used as a long term maintenance therapy that can mediate its therapeutic benefits over the course of an entire day following a single administration. The firm also believes that the agent's unique delivery mechanism will help it achieve an increased concentration at the site of infection, while limiting its systemic presence as much as possible. While Aradigm's liposomal encapsulation approach is unique, the Californian firm is not the only one to be testing an inhalable ciprofloxacin. In February this year for example, Nektar announced that its development partner Bayer plans to begin Phase III trials of a pegylated inhalable version of its product Cipro (ciprofloxacin) Phase III in CF in the next few months. Lowers P.aeruginosa​ count and improves FEV ​​Data from Aradigm study showed that its ciprofloxacin formulation brought about a 1.43 log reduction in the number of colony forming units of the bacteria Pseudomonas aeruginosa​ found in the sputum of patients over the 14 day treatment period. In addition, analysis one week after treatment was stopped revealed that bacterial density in the lung remained at a level 1.02 log lower than baseline without additional antibiotic use. Subsequent pulmonary function testing and forced expiratory volume (FEV) assessment revealed that treatment resulted in a 6.8 per cent improvement in lung function. Tunde Otulana, Aradigm's CMO, said that the firm is "excitied with the magnitude of the efficacy response seen in this proof-of-concept study​." Dr Otulana added that the "results compare well with data [from] other inhaled antibiotics following 14-day treatment in similar subpopulations of CF patients where more frequent dosing was required​." Echoing these thoughts, Aradigm's CEO, Igor Gonda said that the results "will enable Aradigm to advance the development of our liposomal ciprofloxacin product for CF in the US, as well as pursue our strategy for other disease indications including bronchiectasis​."