[Basic research on nedocromil sodium]

Nedocromil sodium is a new chemical entity. This compound is very hydrophilic and is well absorbed by tissues such as the lung but not by tissues with tight junctions such as the gut. This product is chemically different from all drugs currently used for the treatment of airway diseases. The in vitro effects of nedocromil sodium are reviewed. Nedocromil sodium is capable of blocking: 1) the chemotaxis of neutrophils; 2) the activation of macrophages and monocytes by IgE; 3) the release of histamine from mast cells; 4) the cytotoxicity of platelets; 5) the release of LTC4 from eosinophils. Nedocromil sodium thus seems to have an effect on each of the cells which are implicated in the allergic reactions. In animals, nedocromil sodium can block the immediate bronchoconstriction induced by an antigen, adenosine and neurokinin A. Nedocromil sodium can also block the increase in bronchial responsiveness induced by antigen exposure. Moreover, vascular permeability induced by ovalbumin is reduced by nedocromil sodium. In summary, nedocromil sodium demonstrated a significant inhibitory effect of inflammation in both in vivo and in vitro models.