By Jennifer Malloy Zonnas

LOS ANGELES -- A unit of Johnson & Johnson ( JNJ) said a federal jury has ordered Abbott Laboratories ( ABT) to pay $1.67 billion in a patent infringement suit over the companies' rheumatoid arthritis drugs.

Abbott's best-selling drug, Humira, competes with the drug Remicade, an anti-TNF class of arthritis treatments made by J&J's Centocor. That company and New York University filed a patent infringement suit against Abbott in April 2007 in the Eastern District of Texas.

Anti-TNF refers to drugs which block tumor necrosis factor proteins in the blood. When present in excessive amounts, TNF can cause inflammation, which leads to many of the symptoms suffered by those with autoimmune disorders like rheumatoid arthritis.

"We are pleased that the jury has ruled in our favor in the patent litigation case against Abbott," said Kim Taylor, president of Centocor Ortho Biotech, in a statement Monday. "We are particularly gratified that the jury recognized our valuable intellectual property, finding our patent both valid and infringed."

"We are disappointed in this verdict, and we are confident in the merits of our case and that we will prevail on appeal," Abbott spokesman Scott Stoffel responded in a statement.

Humira has been key to Abbott's success story in recent years, racking up approvals for half a dozen uses, including psoriasis and Crohn's disease. Abbott booked $4.5 billion in Humira sales in 2008, and reported sales of $1.02 billion for the 2009 fourth quarter.

Stoffel said evidence "clearly established" that Humira was the first fully human anti-TNF antibody medicine, given that Remicade is partially made from mouse DNA and that J&J didn't launch a fully human product until April of this year.

"J&J acknowledged at trial that it did not start working on a fully-human antibody until 1997 -- two years after Abbott discovered Humira and one year after Abbott filed its patent applications for Humira," Stoffel added.

Taylor said Centocor will continue to assert intellectual property rights for its immunology therapies.

Shares of J&J closed up 36 cents Monday to $56.96. Abbott shares finished up 39 cents at $47.82, but slipped $1.07, or 2.2%, to $46.75 in after-hours trading.

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