Pharmaceutical giant Merck's withdrawn arthritis drug Vioxx is safe enough to rejoin Pfizer's rival pain relievers Celebrex and Bextra on the US market, an advisory panel said.
The 17-15 vote on Vioxx's safety to go to market electrified Merck shares, which closed up 13 per cent at $32.61 on the New York Stock Exchange. Pfizer gained 6.9 per cent to close at $26.80.
The panel concluded that all three medicines posed some level of heart risk.
It was a stunning turnaround for Vioxx, which was withdrawn in September by Merck after a study showed the drug doubled heart attack and stroke risk compared with a placebo in patients who took it for at least 18 months.
Celebrex and Bextra, which had been under the same cloud of elevated risks of heart problems, also could stay on the market, the panel said.
Most members felt all three drugs should have "black box" warnings - the strongest warnings used for prescription drugs - explaining their heart risks.
Many urged restrictions if Vioxx is sold again, such as limiting sales to the lowest dose and recommending it be a second choice after patients try another pain reliever.