SWEDISH pharmaceutical firm Astra has developed a drug -- Losec -- that inhibits acid secretions in the stomach wall and heals ulcers. It has been found that as many as 80 per cent of all ulcer patients will suffer a relapse unless they are given some form of preventive therapy.

US gastro-enterologists believe the Helicobacter pylori (HP) bacterium is responsible for the recurrence of stomach and duodenal ulcers. Anders Vedin, head of research at Astra, corroborates this, saying, "certain biochemical similarities between the HP organism and proteins in the gastric lining.... may lead to damage."

However, Glaxo's medical research director John Wood says the HP bacterium is probably just one of many factors that contribute to ulcer recurrence.