Sucampo Pharmaceuticals, Inc (BETHESDA, Maryland), an emerging pharmaceutical company developing prostone-based therapies for age-related and other diseases, announced that it has enrolled the first patient in a multicenter, phase II, dose-finding trial evaluating the prostone cobiprostone (SPI-8811) for the prevention of ulcers and other gastrointestinal injuries in arthritis patients treated with nonsteroidal anti-inflammatory drugs (NSAIDs).

The double-blinded, randomized, placebo-controlled trial will assess cobiprostone's safety and efficacy in preventing NSAID-induced gastric and duodenal ulcers, erosions, and dyspeptic symptoms in patients with arthritis. The trial plans to enroll approximately 120 patients with osteoarthritis and/or rheumatoid arthritis at up to 15 sites in the US.

The primary efficacy endpoint for the trial is the overall incidence of gastric ulcers during study treatment. The study will also evaluate secondary endpoints including overall incidence of duodenal ulcers; the change in the number of ulcers and/or erosions (gastric and duodenal) by patient; time-to-onset analysis of ulcer and/or erosion development; and the severity of overall gastrointestinal injury by using a standardized grading scale.

Prostones are a class of compounds derived from functional fatty acids that occur naturally in the body. Most prostones work as selective ion channel activators, and their pharmacologic activity is localized where the compound is physically present in its active form. Because some prostones metabolize quickly to an inactive form, their effects tend to be localized, allowing some prostones to be targeted to specific types of cells in specific organs. Cobiprostone is a locally acting chloride-channel activator that works on ion channels located in the liver and the gastrointestinal tract. It has been evaluated in two phase I trials in healthy volunteers and in three phase II proof-of-concept trials in a variety of indications.

According to the company, misoprostol  currently is the only the US FDA-approved drug for reducing the risk of NSAID-induced gastric ulcers; however, the drug is frequently associated with diarrhea and abdominal pain. Proton pump inhibitors are extensively prescribed to treat existing gastric ulcers but have not been approved specifically to prevent ulcer development. Furthermore, there is cause for concern with calcium-absorption interference by these agents in elderly patients and linkages to osteoporosis. H2-receptor antagonists have also been prescribed for preventing NSAID-induced gastric injury, but with limited success.