Merck's Arcoxia, billed as its replacement for Vioxx, demonstrated a comparable risk for cardiovascular events as the anti-inflammatory drug diclofenac, according to a preliminary analysis of its latest study data. But researchers noted that the number of volunteers dropping out of the study due to high blood pressure, edema and congestive heart failure were higher for Arcoxia. The FDA has issued an approvable letter for the drug, seeking more information on it before it makes a final decision. Report