Bone-strengthening drugs from Warner Chilcott Plc, Roche Holding AG, Merck & Co. and Novartis AG may increase risks of fractures and death of jawbone tissue, according to U.S. regulators weighing whether to limit the medicines’ use.
Two Food and Drug Administration advisory committees will meet Sept. 9 to recommend whether patients with osteoporosis should take temporary breaks from the drugs or discontinue use after a certain number of years, FDA staff said today in a preliminary review on the agency’s website.
The FDA has evaluated the safety of the drugs, known as bisphosphonates, for almost four years, citing possible links to joint and muscle pain in 2008 and thigh fractures and jawbone conditions in 2010. The agency said in July it also was examining conflicting studies on whether bisphosphonate pills such as Warner Chilcott’s Actonel, Merck’s Fosamax and Roche’s Boniva raise esophageal cancer risks.
“Data appears to suggest that bisphosphonate therapy could be safely discontinued for some period of time,” FDA staff reviewers said in the report. “However, additional data are needed to further define an appropriate duration of drug holiday” and whether to use interim monitoring.
Bisphosphonates generated $4.2 billion in U.S. sales last year and $7.6 billion worldwide, according to IMS Health Inc. in Norwalk, Connecticut.
Warner Chilcott, based in Dublin, had $1.03 billion in Actonel sales in 2010, according to Bloomberg data. Boniva generated $975 million, while Fosamax had $926 million and Reclast had global sales of $579 million.
Revenue from Fosamax, the first bisphosphonate marketed to treat and prevent osteoporosis in older women, reached $3.19 billion in 2005, then dropped as Merck, of Whitehouse Station, New Jersey, faced competition from generic copies.
More than 40 million people in the U.S. have osteoporosis or are at risk for the disease because of low bone mass, according to the National Institutes of Health in Bethesda, Maryland. The disease causes bone tissue to deteriorate, increasing risks of hip, spine and wrist fractures. Bisphosphonates can reduce fracture risks by slowing bone loss.
Some people who take the medications have experienced “atypical fractures of the thigh” that account for less than 1 percent of all hip and femur breaks, the FDA said in an October safety announcement. The agency required Warner Chilcott, Roche, Novartis, Merck and makers of generic Fosamax to update the drugs’ labels to warn of the possible link.
Atypical fractures “appear to have a strong association with bisphosphonates, although causality has not been determined,” FDA reviewers said in today’s report. “There is no agreement on the extent to which cumulative use of bisphosphonates increases the risk of atypical fractures.”
The agency also is reviewing conflicting studies, based on data from the U.K., on whether oral bisphosphonates can increase the risk of esophageal cancer.
“The available evidence regarding the possible association between oral bisphosphonates and esophageal cancer is inconclusive,” FDA staff said in today’s report. “No conclusion can be reached as to whether long-term use of bisphosphonates is associated with esophageal cancer.”