Inhaled recombinant interferon gamma in patients with lung cancer: Pharmacokinetics and effects on chemiluminescence responses of alveolar macrophages and peripheral blood neutrophils and monocytes

Purpose : A phase I trial was conducted to investigate clinical toxicity, pharmacokinetics, and chemiluminescence (CL) response of alveolar machrophage (AM) and peripheral blood neutrophils and monocytes after inhalation of recombinant interferon (r IFN)-gamma. Methods and Materials : Eight patients with lung cancer inhaled r IFN-gamma as single doses of 0.1, 0.2, 0.6, 1.8, or 5.4 mg. Bronchoalveolar lavage was performed three times, 21 h before as well as 3 and 27 h after inhalation. Results : Interferon-gamma was detectable in bronchoalveolar lavage fluid (BALF) samples taken 3 h after inhalation in doses of ≥ 0.6 mg. Before inhation, AM in four out of seven patients studied showed vigorous lucigenin-enhanced CL responses to N-formyl-methionyl-leucyk-phenylalanine and opsonized zymosan particles. Futhermore, the responses were markedly increase 3 h after inhalation. In three out of seven patients, AM in the pretreatment BALF samples showed low or no CL responses, and the responses did not increase after inhalation of IFN-gamma, suggesting that the patients were anergic. Postinhalation CL responses did not correlate with the dose of IFN-gamma inhaled. Circulating IFN-gamma was detected in one patient receiving the highest dose. No changes referable to IFN-gamma inhalation were found in the CL responses to blood neutrophils and monocytes. During the 24 h follow-up, two patients developed transient fever-reactions. Conclusions : The findings suggest that inhalation may provide a way to increase alveolar concentrations of IFN-gamma and to augment respiratory burst capacity of AM without any major side effects. This approach may have clinical implications for the treatment of tumors and infections of the respiratory tract.