By Farron Cousins

February 11th, 2013

Internal Merck company documents disclosed during the recent trial of Scheinberg v. Merck reveal that the United States Food & Drug Administration “incessantly requested” that Merck make a safer osteoporosis medication than Fosamax.  According to the April 2006 document, authored by Merck researcher Dr. Donald Kimmel: “Long term retention in bone remains a philosophical and now likely real issue.”  Merck’s clinical trials shows that Fosamax has a remarkably long half-life in bone of 10.9 years.  As presented in the Merck document, the FDA’s safety concerns regarding Fosamax include osteonecrosis of the jaw (literally “death of jaw bone”) as well as bone fractures.

Merck is currently in the final stages of clinical trial testing and is attempting to gain new drug approval for its next generation osteoporosis drug: odancatib.  Odancatib is in a class of drug known as “cathepsin-K inhibitors”; Fosamax is in the “bisphosphonate” class of drug.  Most researchers cite Fosamax’s near-complete suppression of bone turnover as the likely culprit for osteonecrosis of the jaw.  Merck has stated that odancatib will present fewer long-term safety issues than the bisphosphonate drugs due to the drug’s unique mechanism of action on bone turnover, which is slightly different than Fosamax’s mechanism.

In an April 2012 earning conference call, when asked about the commercial viability of odancatib in an already-crowded osteoporosis drug market, Merck Chairman and CEO Kenneth C. Frazier noted that there exists “declining use of bisphosphonate [drugs] due to some concerns that have been raised around long term safety”.  Merck expected to file for odancatib’s approval in 2013, however, Merck recently disclosed that it will delay filing the formal application for odancatib marketing approval until 2014.  At its peak, Fosamax generated $3.5 billion per year in annual sales for Merck.  In the United States, Merck has already stopped selling the 35 mg dose of Fosamax.  It is anticipated that Merck will discontinue marketing Fosamax in the United States once it receives marketing approval for odancatib.

Farron Cousins is the executive editor of The Trial Lawyer Magazine, a contributing writer to DeSmogBlog, and a legal writer for the Levin Papantonio law firm.