Abstract 4267: PA32520 (Single-Tablet of Enteric-Coated Aspirin 325 mg + Immediate-Release Omeprazole 20 mg): Aspirin Therapy Combining Greater Thromboxane Suppression and Lower Upper Gastrointestinal Damage
Background: Upper gastrointestinal (UGI) tolerability and safety concerns with aspirin (ASA) have prompted physicians to recommend low-dose ASA. However, low-dose ASA for secondary CV prevention may not have equivalent antiplatelet effects to high-dose ASA, as demonstrated in recent studies. High-dose ASA in combination with proton pump inhibitors may provide a reduction in UGI damage and greater thromboxane suppression.
Methods: In a randomized, single-blinded controlled trial, gastroduodenal mucosal changes using an established methodology (Lanza score) and urinary 11-dehydrothromboxane (TX)B2 were determined in 80 healthy subjects (mean ages 57–58 yrs) with no endoscopic evidence of gastroduodenal mucosal damage (Lanza score 0) who were treated with a daily dose of PA32520 or 81 mg enteric-coated (EC-) ASA. The primary endpoint was Lanza score 3 or 4 (>20 erosions/hemorrhages or ulcers) at Day 28. Study assessments were conducted at baseline, Day 14, and Day 28. In a separate study (n=80), the effect of PA32520 vs. 325 mg EC-ASA alone on gastroduodenal mucosal changes was studied.
Results: PA32520 was associated with a greater reduction in 11-dehydro-TXB2 compared to EC-ASA 81 mg (−75% vs −64% mean percentage change from baseline, respectively; p=0.008) and 50%–84% less gastroduodenal mucosal damage than EC-ASA alone (Table⇓).
Conclusions: Treatment with EC-ASA alone is associated with a high prevalence of UGI damage that is ameliorated by PA32520 therapy. Compared to EC-ASA 81 mg, PA32520 produces superior inhibition of in vivo thromboxane generation. PA32520 may provide an important option for all patients treated with ASA.