PA32540 (a coordinated-delivery tablet of enteric-coated aspirin 325 mg and immediate-release omeprazole 40 mg) versus enteric-coated aspirin 325 mg alone in subjects at risk for aspirin-associated gastric ulcers: Results of two 6-month, phase 3 studies

Background Discontinuations and/or interruptions in aspirin therapy for secondary cardioprotection due to upper gastrointestinal (UGI) complications or symptoms have been shown to increase the risk for subsequent cardiovascular events. PA32540 is a coordinated-delivery, combination tablet consisting of enteric-coated aspirin (EC-ASA) 325 mg and immediate-release (IR) omeprazole 40 mg. Methods Two identically-designed, 6-month, randomized, double-blind trials evaluated PA32540 vs. EC-ASA 325 mg in a secondary cardiovascular disease prevention population taking aspirin 325 mg daily for ≥3 months and at risk for ASA-associated gastric ulcers (GUs). The combined study population was 1049 subjects (524 randomized to PA32540, 525 to EC-ASA 325 mg). The primary endpoint was the occurrence of endoscopically-determined gastric ulceration over 6 months. Safety outcomes included the rates of major adverse cardiovascular events (MACE) and UGI symptoms. Results Significantly fewer PA32540-treated subjects (3.2%) developed endoscopic GUs vs. EC-ASA 325 mg-treated subjects (8.6%) (P <.001). Overall occurrence of MACE was low (2.1%), with no significant differences between treatments in types or incidence of MACE. PA32540-treated subjects had significantly fewer UGI symptoms (P <.001) and significantly fewer discontinuations due to pre-specified UGI adverse events (1.5% vs. 8.2%, respectively; P <.001). Conclusions PA32540 reduced the incidence of endoscopic GUs compared to EC-ASA 325 mg, but with a similar cardiovascular event profile. Due to fewer UGI symptoms, continuation on aspirin therapy was greater in the PA32540 treatment arm.