Journal zyxwvutsrqp of Gastroenterology and Hepatology zyxwvuts (1 995) 10, 379-382 zyxwvu DCBA ALIMENTARY TRACT AND PANCREAS zy W Roxatidine versus ranitidine in the treatment of duodenal ulcers: A randomized double-blind controlled multicentre study in S KM FOCK*, JY KANGt, HS NG’, T M NG*, KA GWEEt AND CC LIMS *Department of Medicine and Division of Gastroenterology, Toa Payoh Hospital,+ National University Hospital and #Medical Unit 11, Singapore General Hospital, Singapore Abstract Roxatidine acetate, a new H, receptor antagonist, was compared with ranitidine in the treat- ment of duodenal ulcers in a double-blind multicentre study. Eighty-four patients with endoscopically proven duodenal ulcer were randomized to receive 150 mg roxatidine acetate or 300 mg ranitidine at bedtime. Repeat endoscopy was performed after 4 weeks (25-33 days) and if the ulcer had not healed, another endoscopy was performed after a further zyxwv LKJIHG 4 weeks of treatment. Using per protocol analysis 73.6% of ulcers treated with roxatidine healed at 4 weeks compared to 72.2% of ulcers treated with ranitidine (P=NS). The healing rates at 8 weeks were 92% with roxatidine and 83.3% with ranitidine (P=NS). Using equivalence tests, the healing rate of roxatidine was found to be equivalent to that of ranitidine within a 20% region. Roxatidine users took significantly less antacids than ranitidine use (Pc 0.05). There were no significant adverse effects due to roxatidine or ranitidine. Roxatidine is a safe effective drug in the treatment of duodenal ulcers with a healing rate comparable to that of ranitidine. Key words: duodenal ulcer, ranitidine, roxatidine. INTRODUCTION The discovery of H, receptors in the gastric mucosa’ and the subsequent development of H, receptor antago- nists in 1975 transformed the treatment of peptic ulcer disease. At present, cimetidine, ranitidine, nizatidine and farnotidine are the H, receptor antagonists in use. Roxatidine acetate is a structurally novel H, receptor antagonist. It is a piperidine derivative rather than an imidazole (as with cimetidine), furan (as with raniti- dine), or thiazole (as famotidine) derivative. It also lacks the 2-thiobutyl connecting chain and urea-like moiety of the other three compounds. Roxatidine acetate is rapidly metabolized to roxatidine in man by first-pass metabolism in the intestinal mucosa, gut-wall and liver as well as by the action of plasma esterase and has a half-life of 6.0-6.5 h2 which is significantly longer than that of the other H, blockers (2-3 h). The healing of duodenal ulcers with anti-secretory therapy is related to the inhibition of post prandial and nocturnal acid secre- t i ~ n . ~ . ~ This trial compares the effects of 150 mg roxati- dine acetate with 300 mg ranitidine taken at bedtime for treatment of active duodenal ulcer in a randomized double-blind design within a 20% equivalence region. METHODS Patients Between November 1991 and March 1993, a total of 84 outpatients with endoscopically proven duodenal ulcers were enrolled from threecentres: Toa Payoh Hospital, Singapore General Hospital and the National University Hospital. Patients zyx FED with previous oesophageal or gastric surgery, pyloric stenosis or concomitant gas- tric ulceration were excluded. Hypersecretory states were excluded. Other exclusion criteria were pregnant or lactating women, presence of serious medical disease, known hypersensitivity to H, blockers and concurrent use of ulcerogenic drugs and non-steroidal anti-inflam- matory drugs(NSAID).Patients who were on anti- ulcer treatment had a washout period of 2 days. The protocol was approved by the Ministry of Health and Correspondence: KM Fock, Department of Medicine and Gastroenterology, Toa Payoh Hospita1,Toa Payoh Rise, Singapore. Accept for publication 8 September 1994.