A New Jersey judge overseeing nearly 3,500 lawsuits claiming injury as a result of taking Merck & Co’s withdrawn painkiller Vioxx (rofecoxib) has insisted that the next cases must involve patients who took the drug for 18 months or more.

The news, which comes just after Merck won the second drug liability trial to come to court [[04/11/05a]], is a blow to the drugmaker as it has always maintained that the cardiovascular side effects linked to Vioxx are very rare in patients who took the drug for a shorter period of time. Selecting patients with longer-term exposure to the drug in subsequent cases will make them much harder to defend, according to a report in the Wall Street Journal. Merck is reportedly planning to fight the decision.

There has already been speculation that Merck may choose to settle some cases where Vioxx use was over 18 months or more, and fight those involving short-term use. Around 60% of the approximately 6,500 Vioxx cases lined up against Merck involve longer-term use, according to the WSJ.

Earlier this month, a New Jersey jury cleared Merck of liability in the heart attack suffered by a man who took Vioxx off and on for about two months [[04/11/05a]]. But an earlier case in Texas – involving a man who had taken the drug over a longer period – went against the company and the court awarded damages of $253 million dollars to the man’s widow [[22/08/05a]]. However, this damages payment looks likely to be capped at around $26 million in accordance with state laws [[12/09/05a]].

The next Vioxx case is due to take place next month and will involve the family of a man who died of a heart attack after taking Vioxx for around a month. Others are scheduled for February, March and April 2006 while, in California, a single trial involving about 1,000 cases is scheduled for June of that year.