Why the FDA Said No to Arcoxia
With hopes of a new osteoarthritis treatment dashed after FDA rejection of the latest COX-2 drug, some OA patients – and doctors – are downright angry.
By Denise Lynn Mann and Donna Rae Siegfried
At a time when treatment options for RA are expanding rapidly – and people with RA are seeing dramatic real-time benefits in terms of disease severity and impact – the news for those with OA isn’t so rosy. The number of treatment options for OA actually has declined with the withdrawal of two of the newer OA drugs from the market in 2004 and 2005.
This spring, there was a glimmer of hope for an addition to the OA treatment arsenal, when the pharmaceutical company Merck went before the U.S. Food and Drug Administration (FDA) Arthritis Advisory Committee to seek recommendation for approval of a new COX-2 drug called etoricoxib (Arcoxia) – one that already has approval in 63 countries. Merck is the company that, back in 2004, voluntarily withdrew its COX-2 drug, rofecoxib (Vioxx), from the market due to an unacceptable risk of heart attack and stroke.
Still, there was reason to hope Arcoxia might be approved, giving people with arthritis a new treatment option. Although there are many traditional nonsteroidal anti-inflammatory drugs (NSAIDs) out there, Arcoxia is different. It’s one of a subset of NSAIDs called the COX-2 inhibitors, which previously included Vioxx and valdecoxib (Bextra) – taken off the market in 2005 – and now includes only celecoxib (Celebrex). (See a timeline on the rise and fall of COX-2.)
COX-2 inhibitors were designed to be safer on the stomach than traditional NSAIDs. Although Arcoxia is a chemical cousin to Bextra, Celebrex and Vioxx, all the COX-2 drugs are not identical. They act in a similar manner – all having been created to squelch inflammation, pain and gastrointestinal irritation – but their slight variations in chemical compositions may create different side effects. For instance, Vioxx showed an increased risk of heart attacks and stroke, but Bextra showed both cardiovascular risks and the risk of a serious skin disease. (See "Weighing Your Risks")
Hope for a new option faded when the Arthritis Advisory Committee voted 20-to-1 against recommending that the FDA approve Arcoxia. The FDA doesn’t have to follow the recommendation of its advisory committees, but it usually does. And in Arcoxia’s case, it did. The FDA formally rejected the application for U.S. approval on April 27.
