Lack of effectiveness of the platelet-activating factor antagonist SR27417A in patients with active ulcerative colitis: A randomized controlled trial

Background & Aims: Platelet-activating factor (PAF) is increased during rel apse of ulcerative colitis. In animal models of experimental colitis, speci fic inhibition of PAF has reduced inflammation. The aim of this study was t o evaluate the efficacy and safety of the PAF antagonist SR27417A in modera tely active UC. Methods: A double-blind multicenter trial was conducted dur ing a 28-day period in hospital outpatients with an exacerbation of ulcerat ive colitis. Patients were randomized to receive 10 mg/day SR27417A or plac ebo, and both groups were also given 2.4 g mesalazine. Patient classificati on at the end of the treatment period was based on sigmoidoscopy and clinic al scores. Results: One hundred fifty-one subjects entered the study (75 pl acebo and 76 SR27417A). The remission rate between placebo- and SR27417A-tr eated patients at 28 days was not significantly different (29.0% and 35.6% respectively; P = 0.44). Similarly, 49.2% treated with SR27417A had a defin ite or possible improvement of their symptom score compared with 48.3% of t hose treated with placebo (P = 0.43). Four subjects in the placebo group an d 5 subjects in the SR27417A group discontinued the drug treatment because of adverse events. No significant adverse events were thought to be caused by SR27417A. Conclusions: Although the specific PAF antagonist SR27417A is safe in humans, there is no evidence of efficacy in the treatment of acute ulcerative colitis.