In Vol 4 No 4 you state that our product Zantac is not approved for maintenance therapy in the US but is in the UK. I enclose a copy of the Physician's Desk Reference which contains a section on maintenance therapy in duodenal ulcers. The UK Datasheet for Zantac does not, as you state, emphasize that the drug should mainly be used for no longer than 12 weeks; it provides recommended dosages for various conditions which may take up to 12 weeks to heal.
The Datasheet then recommends maintenance treatment at reduced dosage when necessary, particularly in those with a history of recurrent ulcer. I enclose a copy of a published paper on the safety and efficacy of long term maintenance threatment with ranitidine.
In the UK we now provide patient information with the packaging for Zantac Tablets, including a section on side effects. You may also be aware that, like all pharmaceutical companies, we are allowed to provide the full Datasheet to patients on request. D D L Higson, Associate Medical Director, Glaxo Laboratories Ltd......
Although we were referring to maintenance therapy for gastric ulcer, which is not approved in the US, thank you for clarifying the position. The Data Sheet Compendium is a bit less restrictive about Zantac's use as a maintenance treatment; however, it does make explicit or implicit the drug's use over a short term for most conditions other than duodenal ulcers.
We note the study you've sent (Alimen Pharma Ther (1992) 6, 629-645) provides persuasive evidence that of 464 patients with duodenal ulcer receiving maintenance treatment with ranitidine, 81 per cent were free from ulcer recurrence after nine years.
We have two problems with it. The first is that it only addresses efficacy, with little mention of safety. Our second reservation is it was funded by your company. Other studies refute these findings: in a study by Jensen et al (Gastroenterology 1990; 98; Suppl: A65) of chronic ulcer patients over three years, ranitidine was superior to a placebo in preventing rebleeding, although the rate of rebleeding in patients taking ranitidine was considerable (9 per cent vs 36 per cent in the placebo group).
We hope that you will notify UK patients of what the US Food and Drug Administration characterized as false and misleading promotional and advertising material for Zantac in violation of the federal Food, Drug and Cosmetic Act.
In the 5 May issue of the Journal of the American Medical Association, James H Lewis, MD, the vice president of medical development marketed products, published an open letter admitting that 1) studies haven't proved that Zantac works better than any other antiulcer drug; 2) the charts Glaxo has been using to show that Zantac is safer than other ulcer drugs haven't taken into account real experience with side effects or important information about drug interactions, such as that between Zantac and warfarin; 3) simply because lots of studies have been done on Zantac it doesn't follow that the drug is safer than other anti ulcer drugs.