A research team out of the Columbia Engineering and Columbia University Medical Center has recently identified a new delivery system for the instillation of medications into the lung. This new development could have a major an impact on future treatment opportunities for several different types of lung disease, including chronic obstructive lung disease, cystic fibrosis, lung cancer, and pneumonia.

Until now, treatment of these conditions required the use of oral or parenteral medications, many of which had side effects that could be eliminated if only the lungs received the medication.  Details on the technique, recently published in Proceedings of the National Academy of Sciences (PNAS), could make a difference in the future management of a variety of lung diseases.

Lung tissue is very complex. It begins with the trachea and branches off into increasingly smaller bronchi and bronchioles that include about 24 generations of branching. The mechanism of uptake of currently available drugs is variable along the branching divisions of the lung. This can have a major impact on the amount of drug necessary to have an effect on the deeper airways of the lungs.

The researchers used tiny liquid plugs of medication and discovered that the level in which the drug absorbed into lung tissue was related to the volume of the liquid plugs. By changing the plug volume and the method of ventilation, medication could be delivered into the deeper airways, forming a micro-film of drug lining the bronchial tree.

Imaging modalities were used to identify where the liquid film landed in the lung tissue at varying liquid plug sizes. The implication is that, in the future, drugs can be delivered to specific areas of the lung, acting locally rather than systemically on the whole body. Side effects from systemic drugs can be greatly diminished if the drug can be locally instilled into the bronchial tree.

Aspects of local instillation of medications in the lungs has already been studied, such as the use of nebulized medication and dry powder inhalers to treat patients with COPD, asthma, and cystic fibrosis. So far, the use of micro-amounts of liquid medication to isolated areas of the lung has not been studied. The development of micro-instillation of liquid plugs into the lungs has future implications in the management of lung diseases that currently require systemic medications to reach the deeper areas of the lungs. Side effects could be greatly reduced along with increased efficacy of lung-based medications.