FDA Accepts New Drug Application for Omeprazole/Aspirin Tablets
Agency decision expected in January 2014 (May 29)
The FDA has agreed to review a new drug application (NDA) for PA32540 and PA8140 (Pozen, Inc.). Both products are a tablet combining immediate-release omeprazole (40 mg), a proton pump inhibitor, layered around a pH-sensitive coating of an aspirin core. PA32540 contains 325 mg of aspirin, and PA8140 contains 81 mg of aspirin.
If approved, the once-daily tablets will be used for the secondary prevention of cardiovascular disease in patients at risk for aspirin-induced gastric ulcers. The user fee goal date is January 24, 2014.
The NDA submission was based on clinical data from two pivotal phase III trials (Study 301 and Study 302) for PA32540 as well as from phase I trials for both PA32540 and PA8140. In the phase III studies, significantly fewer patients taking PA32540 experienced endoscopically confirmed gastric ulcers compared with patients who received enteric-coated aspirin alone (Study 301: 3.8% vs. 8.7%, respectively; P = 0.02; and Study 302: 2.7% vs. 8.5%; P = 0.005).
The two phase III, double-blind, randomized trials enrolled 1,049 subjects who had been prescribed daily aspirin (325 mg) for at least 3 months for secondary prevention of cardiovascular events. The primary endpoint was the cumulative observed incidence of gastric ulcers over 6 months. Secondary endpoints included the cumulative incidence of gastric and duodenal ulcers, discontinuation due to upper gastrointestinal (UGI) adverse events, and heartburn resolution.
The patients were randomly assigned to receive once-daily treatment with PA32540 or 325 mg of enteric-coated aspirin. Endoscopic assessments were performed at screening and at 1, 3, and 6 months.
Each of the two studies achieved its individual primary endpoint and met all secondary endpoints. Combined data from the two studies demonstrated that patients treated with PA32540 were able to remain on therapy longer because of fewer discontinuations due to adverse events compared with patients treated with enteric-coated aspirin (6.7% vs. 11.2%, respectively). Moreover, the rate of discontinuations due to UGI events was lower in patients taking PA32540 compared with those taking enteric-coated aspirin (1.5% vs. 8.2%, respectively; P < 0.001).
In combined data from the two trials, 85.1% of subjects treated with enteric-coated aspirin reported adverse events compared with 71.8% of patients treated with PA32540. The most commonly reported adverse events with PA32540 and enteric-coated aspirin involved the GI tract and included dyspepsia (11.3% vs. 30.2%, respectively), erosive gastritis (11.5% vs. 26.3%), and gastritis (17.5% vs. 16.0%). The incidence and nature of major adverse cardiac events (MACE), such as heart attacks, were similar between the two treatment arms: nine subjects (1.7%) treated with PA32540 experienced MACE compared with 13 subjects (2.5%) treated with aspirin.
Source: Pozen, Inc.; May 29, 2013.