Barr Laboratories will pay $22.5 million to Sandoz to settle a lawsuit that alleged Barr unlawfully blocked access to the raw material source for warfarin sodium, Barr said June 12, the day the trial was to start.

The suit originated as two lawsuits filed by Invamed and Apothecon, companies which have both since been acquired by Sandoz.

Warfarin is sold by Bristol-Myers Squibb as the brand drug Coumadin, and is also sold in generic form by other companies. Barr was the first to launch generic warfarin sodium in 1997. The drug is indicated to prevent blood clots in patients with certain types of irregular heartbeats or who have had a heart attack or heart-valve replacement surgery.

"While Barr believes that the lawsuit filed against it by Invamed and Apothecon was without merit and that our agreement with our raw material supplier was lawful, we made what we believe is a prudent decision to settle the claims to avoid further defense costs and valuable management resources," Bruce L. Downey, Barr's chairman and chief executive officer, said in a statement.