Objective

Neutrophil elastase is believed to be an important mediator of acute lung injury. Sivelestat (ONO-5046, Elaspol) is a small molecular weight inhibitor of neutrophil elastase. The primary objectives of this study were to determine whether sivelestat would reduce 28-day all-cause mortality or increase the number of ventilator-free days (days alive and free from mechanical ventilation from day 1 to day 28) compared with placebo in mechanically ventilated patients with acute lung injury.

Design

Multiple-center, double-blind, placebo-controlled trial administering a continuous infusion of sivelestat at a dose of 0.16 mg.kg(-1)hr(-1).

Setting

One hundred and five institutions in the United States, Canada, Belgium, Spain, Australia, and New Zealand.

Patients

A total of 492 mechanically ventilated patients with acute lung injury.

Interventions

Patients were randomized in a 1:1 fashion to sivelestat or placebo. Study drug was administered as a continuous infusion for the duration of mechanical ventilation plus 24 hrs for a maximum of 14 days. All patients were managed using low tidal volume mechanical ventilation.

Measurements and main results

The study was stopped prematurely at the recommendation of an external Data and Safety Monitoring Board, which noted a negative trend in long-term mortality rate. Final analysis revealed no effect of sivelestat on the primary end points of ventilator-free days (day 1-day 28) or 28-day all-cause mortality. There were 64 deaths in each treatment group within the 28-day study period, and the mean number of ventilator-free days was 11.4 and 11.9 in the sivelestat and placebo treatment groups, respectively (p =.536). There was no evidence of effect on measures of pulmonary function, including Pao2/Fio2, static lung compliance, and time to meeting weaning criteria. There was no difference in adverse events or serious adverse events between treatment groups. A comparison of the Kaplan-Meier 180-day survival curves showed no difference between treatment groups (p =.102), but there was an increase in 180-day all-cause mortality in the sivelestat treatment group compared with the placebo group (p =.006).

Conclusions

Intravenous sivelestat had no effect on 28-day all-cause mortality or ventilator-free days in a heterogeneous acute lung injury patient population managed with low tidal volume mechanical ventilation.