Combination therapy could revive Vioxx, says study

Combination therapy could one day help to resurrect Merck & Co's COX-2-selective inhibitor Vioxx (rofecoxib) if findings in the Journal of Experimental Medicine hold true.

A new study by scientists led by Dr Timothy Hla at Pennsylvania State University suggests the drug's cardiovascular side-effects, which led to its global withdrawal in 2004, could be tackled by giving patients PPAR-delta agonists, a currently experimental class of drugs for diabetes.

In mice, Hla and colleagues found that blocking the COX-2 receptor, target of the coxib drugs, stimulated the production of tissue factor, a blood clotting agent that can contribute to heart attacks and stroke. This occurred as a downstream consequence of stimulating the production of natural pain-relieving molecules, endocannabinoids.

However, the researchers were able to reduce the amount of tissue factor in the blood by giving the mice tissue factor-reducing drugs.

"It is theoretically possible to treat people safely with Vioxx and other COX-2 inhibitors if existing TF-blocking drugs are given simultaneously," the researchers conclude.

The findings could also be applied to other coxibs such as Pfizer's Celebrex (celecoxib) and Novartis's Prexige (lumiracoxib), which recently saw its use restricted after rare reports of severe liver damage.