When drug company Merck revealed the the results of a study this week over it's successor to Vioxx, the new arthritis drug Arcoxia, it did little to quell concerns about both the use and the safety of the new drug.
Both Vioxx and Arcoxia are painkillers known as Cox-2 inhibitors; Vioxx was withdrawn from the market in September 2004, after a study found it doubled heart attack and stroke risks.
In the largest-ever trial of an arthritis drug, researchers tested Arcoxia against an older treatment, the generically available diclofenac and gathered data from three trials involving almost 35,000 patients with osteoarthritis and rheumatoid arthritis.
The study looked at patients aged 50 or older who were treated for an average of 18 months.
Since their initial appearance in 1999, Vioxx and other Cox-2 drugs such as Pfizer's Celebrex and Bextra had been lauded as super aspirins which were better and safer than older painkillers.
The drugmakers promised they would ease pain without causing serious stomach bleeding and ulcers, an effect of common drugs known as non-steroidal anti-inflammatory drugs (NSAID's) such as ibuprofen, naproxen and diclofenac.
Merck is chasing U.S. approval for Arcoxia (etoricoxib), and has been comparing its effects to those of the NSAID's.
In a presentation at the American Heart Association annual meeting, Merck said its 35,000-patient programme, called Medal, found that Arcoxia had similar heart risks to diclofenac, a NSAID and has forwarded the the data which is also published in The Lancet – to the Food and Drug Administration (FDA).