LEXINGTON, Mass.--(BUSINESS WIRE)--Critical Therapeutics (Nasdaq: CRTX) today announced the start of patient enrollment in the LEUKO study, a randomized, double-blind, placebo-controlled efficacy trial to examine the effects of ZYFLO® (zileuton tablets) used in the treatment of adults with Chronic Obstructive Pulmonary Disease (COPD). The purpose of this trial is to examine the effectiveness of ZYFLO at reducing the length of a hospital stay for adults who are hospitalized for a COPD exacerbation, or a worsening of their COPD symptoms. Secondary outcomes will include lung function improvement, “treatment failure” at 30 days (defined as intubation, hospital re-admission or urgent visit for COPD symptoms, or intensification of therapy), health-related quality of life and urinary leukotriene levels.