Merck's Fosamax Could See Sales Hurt by Study: CNBC's Huckman

Sales of Merck's third-biggest drug, Fosamax, could come under pressure after a new study found that people with osteoporosis could stop taking the drug after five years and still get the residual benefits, CNBC's Mike Huckman reports.

In an article in the Journal of the American Medical Association, researchers said that people who took Fosamax for five years and then stayed off it for another five continued to benefit from having taken the drug in the first place.

In fact, researchers said that it was almost the same as if they kept using the drug for a full ten years.


The only statistically significant difference was a 55% lower risk of vertebral fractures in the group that took Fosamax for the entire decade.

Doctor Ken Lyles at Duke University, who was privvy to the study results and has already started acting on them, said he thinks that 60% to 70% of long-term users could stop taking Fosamax now.

Dr. Lyles has received consulting fees from nearly every major company that sells or is developing an osteoporosis drug. Sanofi-Aventis, Proctor & Gamble,Roche and GlaxoSmithKline make drugs similar to Fosamax.

Merck, which paid for the JAMA study, said in a prepared statement: "This is another positive study for Fosamax...that the data reinforce the safety profile and clinical benefits of long-term treatment with Fosamax."

Merck had been forecasting as much as a half-billion dollar decline in Fosamax sales next year before this news hit right at the market close.