Anti-TF Antibody (ALT-836) to Treat Septic Patients With Acute Lung Injury or Acute Respiratory Distress Syndrome

This is a prospective, randomized (1:1), double-blind, multi-center, Phase II clinical study to test the safety and efficacy of a recombinant chimeric anti-tissue factor antibody (ALT-836) versus placebo in patients with sepsis and acute lung injury/acute respiratory distress syndrome (ALI/ARDS). This study was divided into two parts and the first part of the study has been completed. In the first part of the study, sixty patients were randomized at a 1:1 ratio to receive one dose of the study drug or placebo. In the second part of the study, ninety patients will be randomized at a 1:1 ratio to receive a multi-dose treatment regimen of single doses every 72 hours up to a maximum of 4 doses of the study drug or placebo, provided there are no safety concerns.

Tissue factor (TF)-dependent procoagulant activity and associated inflammatory processes may play a role in the severity and progression of ALI/ARDS. Recent studies demonstrated that TF levels were elevated in plasma and pulmonary edema fluid of ARDS/ALI patients compared to control patients with hydrostatic pulmonary edema. These higher plasma TF levels were correlated with increased mortality, fewer ventilation-free days, the presence of disseminated intravascular coagulation and the presence of sepsis in patients with ALI/ARDS, suggesting that systemic activation of coagulation may be clinically important in ALI/ARDS. Moreover, the pulmonary TF levels in patients with ALI/ARDS were found to range between 0.5 and 2 nM, approximately 100-fold higher than simultaneous plasma levels, suggesting an intra-alveolar source of TF. Thus, anti-TF antibody blockage of TF activity may therefore provide an effective therapeutic mechanism for the treatment of inflammatory disorders such as ALI and ARDS. This study will test the hypothesis that administration of anti-TF antibody (ALT-836) to septic patients with ALI/ARDS will improve the clinical outcome by shortening the duration of mechanical ventilation for these patients.