Merck took the decision to withdraw the COX-II inhibitor Vioxx from the market in the light of preliminary data from a three-year clinical trial known as APPROVe, which found an increased relative risk for confirmed cardiovascular events, such as heart attack and stroke, from 18 months after the start of treatment, compared with a placebo.
Since then, some supplement makers have reported an increase in sales of their joint health products, such as Leiner Healthcare in its full year 2005 results released last month.
Mintel's Global New Products Database includes 15 new joint health, inflammation and osteoarthrisis dietary supplement products launched in the first half of 2005, but given the amount of time needed for product development, it is too early to see whether the Vioxx fall-out has prompted companies to devote resources to this potentially fruitful segment.
But Mintel does show a high - if somewhat oscillating - level of launches over the past five years: 44 in 2004; 69 in 2005; 40 in 2002; 61 in 2001 and 43 in 2000.
And throughout this period, by far the most popular ingredient is glucosamine, contained in 48 percent of all products. Chondroitin is contained in 24 percent of the new products in Mintel's database.
According to Euromonitor, sales growth of products containing glucosamine has slowed considerably since 2000. Between 1997 and 1998 retail sales grew by 72 percent, then by 37 and 21 percent in the next two years. But in 2001 growth was just 5 percent, and in 2002 the market actually declined slightly.
Euromonitor predicts sales of almost $790 million in 2005, and anticipates renewed growth of between 2 and 3 percent over the next two years, which could perhaps be attributed to the Vioxx effect.
In terms of glucosamine product market share, Rexall Sundown's Osteo Bi-Flex has led the pack since its launch in 2003. Last year it had an 11.3 percent share of the market. Weider's Shiff, in second place, had 3.9 percent.
But new ingredients are also appearing to woo concerned consumers. Two new products containing natural milk protein microlactin (Puritan's Pride's Active Joints with MicroLactin Caplets and Nature's Bounty's Vital Joint) show up amongst Mintel's new products in 2004 and 2005.
According to Dynamic Nutritional Products, which announced the launch of its trademarked MicroLactin supplement in May, clinical trial have shown it to be as much as 60 percent more effective than glucosamine at reducing the inflammatory pain of osteoarthritis.
This week Gelita Health Products announced the US launch of CH-Alpha, a supplement containing collagen hydrolysate, which the company claims is the only one on the market to support cartilage regeneration.
Data source: Mintel's Global New Products Database.