In his talk on “Phage Therapy for Pulmonary Infections: The Challenges of Choosing, Growing, and Purifying Phage for Clinical Use,” Benjamin Chan of Yale University provides a brief overview of how bacteriophages work followed by a description of what he calls “phage therapy 2.0,” targeting virulence and antibiotic resistance factors. This approach involves selection of bacteriophages to target the infection and then giving them serially instead of as a cocktail.
Chan presents several case studies, including one in which cystic fibrosis patient with a pan-resistant P. aeruginosa lung infection who received nebulized phage therapy was re-sensitized to almost all antibiotics, resulting in improved lung function that has been sustained for several years. He reports that his group has seen re-sensitization to antibiotics in all cases treated, with an average 7% improvement in FEV1 after phage therapy.
Reinhold Vehring of the University of Alberta also discusses phage therapy in his talk, “Tuberculosis Therapy and Prophylaxis: Conquering Formulation and Delivery Problems with Inhaled Vaccines and Phages.” Vehring, who has been working with phages for a decade asserts, “We need to find an alternative to small molecule antibiotics. Either we find a whole lot more of them, which doesn’t seem likely, or we need some alternative.”
Vehring acknowledges that “For tuberculosis, phages face quite a hurdle because tuberculosis bacteria are good at walling themselves off,” but also notes that “There is very good reason to believe that phage therapy can cure even very difficult infections.” He cautions that the delivery method is critical as certain types of nebulizer can inactivate phages; he is working on a dry powder therapy, which also would make it easier to deliver the high dose necessary for effective treatment.
In addition to the phage formulation project, Vehring also describes delivery of liquid-adjuvanted inhaled tuberculosis vaccine formulated as a dry powder, about which he says: “That I think is groundbreaking because it demonstrates that even relatively complex vaccines can be stabilized into a dry powder form with potential for global distribution.”
Sustainability continues to be a major focus
The sustainability of OINDPs, especially of metered dose inhalers, continues to generate significant discussion following a major focus on sustainability issues at DDL 2019. A number of Digital RDD 2020 presenters highlighted the development of alternative MDI propellants, as well as recycling and improved adherence as potential targets for the reduction of the carbon footprint associated with inhaled drugs.
