In 2001 it derived 34% of its revenue from its dyspepsia medicine, Prilosec (omeprazole).

FORBES: Modesty ablaze

The original patent on omeprazole, the active chemical in Prilosec, ran out on Oct. 5.

FORBES: Magazine Article

AstraZeneca's lawyers say the generic companies that are working on their own versions of omeprazole infringe on the patents for this drug delivery system.

FORBES: Fight Over $6 Billion Drug Begins

One major problem: the looming threat of patent expiry on its most popular remedy, the antiulcer drug omeprazole, sold as Losec (in the U.S. as Prilosec).

FORBES: Another Look

Also, certain medicines, such as proton pump inhibitors Prilosec (omeprazole) and Nexium (esomeprazole), reduce the effect of clopidogrel, leaving a person at greater risk for heart attack and stroke.

FORBES: FDA Approves Generic Clopidogrels As Plavix Loses Patent Protection

Omeprazole by itself doesn't make an effective pill.

FORBES: Fight Over $6 Billion Drug Begins

On its face, that could set up a situation where only KUDco and AstraZeneca can sell Prilosec in the U.S. Such a result would keep the cost of the drug, also known as omeprazole, relatively high.

FORBES: Magazine Article