The Vioxx recall has shaken the once mighty Merck. The company earlier this week said that as of Oct. 31, some 475 personal injury lawsuits have been filed against the company relating to its withdrawal of Vioxx from the market on Sept. 30. Product liability cases include 1,100 plaintiff groups. At this point, the two cases are dramatically different, but the cancer trial data are bound to renew speculation about the safety of Celebrex for treating arthritis. In mid-October, Pfizer announced plans to fund additional clinical testing of Celebrex to determine its effect on arthritis patients who have had a recent heart attack. Another Pfizer COX-2 inhibitor drug, Bextra, has recently drawn attention because of possible side effects, including a rare but potentially fatal skin rash, as well as some research that says Bextra patients undergoing cardiac bypass surgery had a higher risk of heart-related complications. Pfizer has released research showing that there are no increases in cardiovascular risks among patients who took Bextra for between six weeks and 52 weeks.