Thrombomodulin for acute exacerbations of idiopathic pulmonary fibrosis: a proof of concept study

Introduction: The mortality of acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is high. Anticoagulation therapy (recombinant human soluble thrombomodulin (rhTM)) is recognized as a potential new strategy for treating disseminated intravascular coagulation in Japan. This preliminary study was to evaluate whether the coagulation factors increase or decrease in AE-IPF-patients, and whether the additional administration of rhTM for AE-IPF-patients has any beneficial effects on inflammatory mediators and activated coagulation.

Methods: We retrospectively compared the clinical data of AE-IPF-patients, idiopathic pulmonary fibrosis (IPF) with pneumonia-patients and slowly progressive IPF-patients. As a subsequent study, AE-IPF-patients were prospectively treated with a bolus of rhTM intravenously for six days under mechanical ventilation. We historically investigated the improvement of the serial clinical data in both oxygenation and intravascular coagulation disturbance between treated AE-IPF-patients and untreated AE-IPF-patients.

Results: Eleven AE-IPF, 21 IPF with pneumonia and 16 slowly progressive IPF-patients were enrolled, and the coagulatory levels of the AE-IPF-patients were found to be significantly higher than in the other patients. In 20 treated AE-IPF-patients, the 28-day mortality and in-hospital mortality were 35% and 45%, respectively. The levels of oxygenation rapidly increased on day 1 and continued to improve until day 7 in the survival AE-IPF-patients. The thrombin-antithrombin complex levels and inflammatory cytokine levels in the survivors on day 7 were significantly different from those observed in the nonsurvivors.

Conclusion: AE-IPF-patients were found to have significantly higher levels of coagulation. The rhTM administration in the surviving AE-IPF-patients led to significant differences in the oxygenation and intravascular coagulation disturbance.