Inhalable mRNA dry powder promising for lung disease management

An inhalable dry powder formulation of mRNA developed by researchers at the University of Hong Kong has shown promise in the treatment of lung diseases.

The formulation was developed using PEG₁₂KL4, a pegylated cationic peptide, as RNA delivery vector. With the use of spray drying and spray freeze drying techniques, PEG₁₂KL4/mRNA complexes were formulated into dry powder with satisfactory aerosol properties for inhalation. [J Control Release 2019;314:102-115]

Intratracheal administration of luciferase mRNA using the above formulation resulted in luciferase expression in the deep lung region of mice 24 hours post-transfection, with superior transfection efficiency compared with naked mRNA or lipoplexes, which led to weaker luciferase expression in the tracheal region only. No sign of inflammatory response or toxicity was reported with the PEG₁₂KL4/mRNA complexes following a single intratracheal administration.

According to the investigators, the inhalable mRNA dry powder can potentially be used to treat lung diseases such as asthma, chronic obstructive pulmonary disease and cancer. The team is now developing an inhalable mRNA vaccine based on their discovery.

The inhalable mRNA dry powder is more stable and patient-friendly, with a lower treatment cost, compared with liquid formulations administered by nebulization using bulky devices, they added.