Sulfasalazine, the prototype aminosalicylate that combines sulfapyridine (an antibiotic) with the anti-inflammatory 5-ASA, was found to be efficacious for UC in the 1940s. It was not until the 1970s that 5-ASA was recognized as the active moiety, with the sulfapyridine component acting as an inert carrier molecule that delivers the 5-ASA to the site of active mucosal inflammation in the colon only.
2 This discovery and the recognition that the “sulfa” component was responsible for most of the allergic and dose-dependent side effects of sulfasalazine led to the development of…