keywords: celebrex vioxx pfizer risks risk
text: Celebrex Lifts Heart Attack Risk in Trial  NEW YORK (Reuters) - Pfizer Inc. on Friday said its popular  Celebrex arthritis drug more than doubled the risk of heart  attack in a large cancer-prevention trial, a setback that comes  just weeks after Merck   Co. recalled its similar Vioxx drug  due to heart safety risks.