Par Pharmaceuticals said it began shipping an authorized generic version of AstraZeneca beta blocker Toprol-XL.
The announcement followed the launch of a 25-mg generic version of metoprolol in the US by Eon Labs, part of Sandoz.
Par’s authorized generic also is being distributed in a 25-mg dosage, a size which accounts for about 20% of Toprol-XL US sales, AZ said. Toprol-XL had $838.9 million in sales during the first six months of 2006 and $1.49 billion in sales in 2005, according to IMS Health.
An extended-release pill whose patent expires in September 2007, Toprol-XL’s patent was deemed invalid earlier this year in litigation involving KV Pharmaceutical, Andrx Pharmaceuticals, Andrx Corp. and Eon Labs Manufacturing. AZ appealed that decision and, notwithstanding its deal with Par, said it will continue to sell branded Toprol-XL in the US.