Inhalable ceftazidime-roflumilast powder targeting infection and inflammation: Influence of incorporating roflumilast into ceftazidime-leucine co-amorphous formulation

Co-amorphization of a single drug with amino acid is a technique to improve aerosolization of inhalable spray-dried formulation for inhalation therapy. However, the incorporation of a second drug molecule into drug-amino acid co-amorphous particles to prepare combination formulations has not been explored. Here, we prepared combination powders using two model drugs, ceftazidime and roflumilast, which when concurrently used can potentially improve therapeutic outcome in non-cystic fibrosis bronchiectasis by counteracting both infection and inflammation. The study was performed using a two-step approach. The first step involved the identification of an amino acid and its concentration (%