Interobserver variation in the endoscopic diagnosis of gastroduodenal ulcer scars: implications for clinical management of NSAIDs users

Exploiting drug delivery systems for oral route in the peptic ulcer disease treatment

Peptic ulcer disease (PUD) is a common condition that is induced by acid and pepsin causing lesions in the mucosa of the duodenum and stomach. The pathogenesis of PUD is a many-sided scenario, which involves an imbalance between protective factors, such as prostaglandins, blood flow, and cell renewal, and aggressive ones, like alcohol abuse, smoking, Helicobacter pylori colonisation, and the use of non-steroidal anti-inflammatory drugs. The standard oral treatment is well established; however, several problems can decrease the success of this therapy, such as drug degradation in the gastric environment, low oral bioavailability, and lack of vectorisation to the target site. In this way, the use of strategies to improve the effectiveness of these conventional drugs becomes interesting. Currently, the use of drug delivery systems is being explored as an option to improve the drug therapy limitations, such as antimicrobial resistance, low bioavailability, molecule degradation in an acid environment, and low concentration of the drug at the site of action. This article provides a review of oral drug delivery systems looking for improving the treatment of PUD.

Endoscopic ulcers as a surrogate marker of NSAID-induced mucosal damage

The characteristic of a biomarker that makes it a useful surrogate is the ability to identify a high risk of clinically important benefits or harms occurring in the future. A number of definitions or descriptions of surrogate definition have been put forward. Most recently the Institute of Medicine of the National Academy of Sciences in the USA has put forward an evaluation scheme for biomarkers, looking at validation (assay performance), qualification (assessment of evidence), and utilisation (the context in which the surrogate is to be used). This paper examines the example of endoscopy as a surrogate marker of NSAID-induced mucosal damage using the Institute of Medicine criteria. The article finds extensive evidence that the detection of endoscopic ulcers is a valid marker. The process of qualification documents abundant evidence showing that endoscopic ulcers and serious upper gastrointestinal damage are influenced in the same direction and much the same magnitude by a variety of risk factors and interventions. Criticisms of validation and qualification for endoscopic ulcers have been examined, and dismissed. Context is the key, and in the context of serious NSAID-induced upper gastrointestinal harm, endoscopic ulcers represent a useful surrogate. Generalisability beyond this context is not considered.