Merck & Co.'s patent on its blockbuster osteoporosis drug Fosamax has run out and faces its next big patent expiration in 2010, when the $3 billion-a-year Cozaar/Hyzaar hypertension franchise loses protection.

Generic drugmakers such as Teva Pharmaceuticals and Barr Pharmaceuticals will roll out their low-cost versions.

Fosamax sales totaled $3 billion in 2007, but Merck projects that 2008 sales will decline by at least half that, followed by further erosion later on.

Hopefully this will mean cheaper access to good treatments for conditions like Osteoporosis.