Novartis has won approval across the European Union for Prexige, its COX-2 inhibitor, as a new treatment option for patients suffering from osteoarthritis, the most common form of arthritis and a leading cause of chronic pain.

Prexige (lumiracoxib) was first approved and launched in the UK at the end of 2005, and has now completed the Mutual Recognition Procedure in the EU.

The launch comes at a difficult time for the COX-2 inhibitor class, still feeling the effects of the withdrawal of Merck & Co's Vioxx (rofecoxib) in 2004, after the drug was linked to an increased risk of heart attack and stroke. After Pfizer's Bextra (valdecoxib) went the same way as Vioxx, Novartis decided to hold off launching Prexige (lumiracoxib), while it carried out additional clinical testing on the product.

Prexige joins Pfizer’s Celebrex (celecoxib) and Dynastat (parecoxib) on the market at a time when the marketed products seem to be shrugging off the impact of Vioxx’ withdrawal. Although sales of the drugs declined in the aftermath, Celebrex in particular has been staging a recovery and posted sales of $537 million in the third quarter of 2006, up 20%.

Celebrex looks almost certain to top the $2 billion barrier this year, a threshold which was billed at the start of the year as an ambitious target for a drug that pulled in $3.3 billion in 2004.

Novartis expects Prexige to become available in other European countries during 2007 and 2008, muscling into Pfizer’s COX-2 monopoly, and the company confirmed its plan to resubmit Prexige for US approval in 2007.

In addition to the EU, Prexige is already approved in more than 25 countries, including recently in Canada, and has captured a 29% share of new prescriptions in Brazil, the first country in which it was introduced.

This, coupled with claims of a superior gastrointestinal safety profile compared to other COX-2 inhibitors, has prompted some analysts to look again at its sales forecasts and wonder whether Prexige could tilt at blockbuster status, with sales in excess of $1 billion a year. Others believe that revenues of $500 million or so are more likely, given that Prexige will have a tough time overcoming the Vioxx stigma.

Novartis noted that Prexige will be available in 100mg tablets, given once daily, for symptomatic relief in the treatment of knee and hip osteoarthritis. The decision was based on data from clinical trials involving approximately 34,000 patients.