Merck & Co., Inc. (NYSE: MRK) has headed back to the Food and Drug Administration with a drug that is meant to replace Vioxx. [subscription required] The Big Pharma company is still facing a number of lawsuits over whether Vioxx caused heart problems and stroke in some patients.

Merck's new drug is called Arcoxia and it is from the same category of drugs that Vioxx is, but the company has done extensive testing and is already selling the drug outside the US. Still, Arcoxia appears to have problems of its own as it has caused high blood pressure in some patients who are taking it in the trials.

Vioxx brought in $2.5 billion in revenue for Merck in 2003. However, the potential liability of the lawsuits against Merck could be as much as $15 billion.

Merck is left with a tough decision. Even if its new drug is approved for use in the American market, it would appear that it is not without side effects. And, side effects are already costing Merck a bundle, if only in legal fees.

Douglas A. McIntyre is a partner at 24/7 Wall St.

Like most of the Big Pharma companies, Merck & Co. (NYSE:MRK) needs a winner. Wall St. is scared witless that generic drug firms like Teva Pharmaceutical Industries (NASDAQ:TEVA) will scoop up all of the customers as drugs come off patent.

With Wal-Mart Stores, Inc. (NYSE:WMT) and every corner store offering $4 prescriptions for generic drugs, the sun may be setting on operations like Merck.

Merck is trying to get its new painkiller [subscription required], Arcoxia, out the door without physicians thinking it has health risks like the company's heart-unhealthy drug Vioxx.

Arcoxia is already controversial and it is not even for sale in the U.S. with some doctors thinking the drug could be as dangerous as Vioxx. However, a study presented at the recent American Heart Association conference indicated that the drug was fairly safe. Only 1% of the people on the drug suffered a heart attack, stroke, or death within the first year.

Great odds if you are not the patient who died.

Douglas McIntyre is a partner at 24/7 Wall St.