Randomized, double-blind phase II trial of Lexipafant, a platelet-activating factor antagonist, in human acute pancreatitis

The aims of the study were to determine whether the platelet-activating factor antagonist Lexipafant could alter the clinical course and suppress the inflammatory response of human acute pancreatitis. In a double-blind, placebo-controlled study 83 patients were randomized to receive Lexipafant 60 mg intravenously for 3 days, or placebo. Clinical progression was assessed by daily Acute Physiology And Chronic Health Evaluation (APACHE) II score and organ failure score (OFS). The magnitude of the inflammatory response on days 1-5 was assessed by serial measurement of interleukin (IL) 8, IL-6, E-selectin, polymorphonuclear elastase-alpha1-antitrypsin (PMNE-alpha 1-AT), and C-reactive protein (CRP). At entry, patients receiving Lexipafant (n = 42) or placebo (n = 41) were matched for age and sex, aetiology, APACHE II score and OFS. The disease was classified as severe in 29 patients (APACHE II score eight or more). There was a significant reduction in the incidence of organ failure (P = 0.041) and in total OFS (P = 0.048) at the end of medication (72 h). During this time seven of 12 patients with severe acute pancreatitis who had Lexipafant recovered from an organ failure; only two of 11 with severe acute pancreatitis who had placebo recovered from an organ failure and two others developed new organ failure. Lexipafant treatment significantly reduced serum IL-8 (P = 0.038), and IL-6 declined on day 1. Plasma PMNE-alpha 1-AT complexes peaked on day 1; the gradual fall to baseline over 5 days observed in controls did not occur in patients given Lexipafant. No effect was observed on serum CRP. This study provides a rationale for further clinical trials with the potent PAF antagonist Lexipafant in human acute pancreatitis.