Cyclodextrin-based materials for pulmonary delivery: Insights and challenges

Cyclodextrins (CDs) are cyclic oligosaccharides primarily used as excipients in the formulation of drugs, including those intended for pulmonary delivery. CDs have gained increased attention for their use as drug solubilizers. The beneficial role they play in the formulation of drugs intended for lung targeting has received particular attention in recent years, along with the potential benefits this route offers for achieving systemic effects. Hence, various CDs based materials have been considered in literature including CD/drug inclusion complexes, polymerized CDs and nanosponges, metal-organic frameworks, CDs in proliposomes, and others. The investigation of CDs as active agents is also considered in literature for the treatment of lungs diseases. The literature provides a large range of information on the manufacturing of CD-based materials for pulmonary delivery, the characterization of the obtained formulations, their suitability for lung deposition, the pharmacokinetics of the drugs when loaded in a particular formulation, and the resulting biological effects, yet the challenges of their clinical translation remain to be addressed.