The longstanding legal battle between Teva Pharmaceuticals Industries Ltd, the Israeli-based generic drug manufacturer, and Merck & Co over the validity and enforceability of Merck's patent on its once-weekly FosamaxR may now be decided by the US Supreme Court.

Merck recently announced that it intends to challenge the recent rejection by a US Appeals Court of a request to reconsider a decision that would allow the patent to expire in 2008, 10 years earlier than the company had hoped. With worldwide sales last year of over $3 billion, both companies are likely to vigorously defend their position.

Merck has continued to strengthen its Fosamax franchise through the introduction of additional offerings such as the recently FDA approved alendronate sodium/cholecalciferol (Fosamax Plus DR) which is supplemented with a weekly dose of vitamin D.