Barr Pharmaceuticals Inc. said on Thursday the U.S. Food and Drug Administration has given final approval for its generic capsule version of Aventis Pharmaceutical Inc.‘s popular allergy drug Allegra.

Barr said it was the first company to file an Abbreviated New Drug Application (ANDA) with the FDA that included a patent challenge for the Allegra capsule drug.

Aventis, part of giant European drug company Sanofi-Aventis, had filed suit to prevent approval until its last patent on the drug expires in 2017. While the court ruled on some patents last year, Barr said it expects the rest to face trial in early 2006.

Barr spokeswoman Carol Cox said the company had no set launch date and planned to wait until after the legal issues were resolved to make a decision. “We’re not selling it now,” she said.

If it does start selling it, or when the trial ends - whichever comes first - the company is entitled to 180 days of exclusive marketing of a generic version because it was the first to file with the FDA, Barr said.

Cox said the capsule version did not have a large market. The brand name capsules took in annual sales of $14,000 before Aventis discontinued the product, according to Barr.

Aventis also makes a tablet version, which Barr is also pursuing. Barr also has FDA approval for the 12-hour Allegra-D tablet, which is also locked up in a legal fight.

“The market is really in the tablets and in the Allegra-D,” Cox said.

Shares of New Jersey-based Barr were up 10 cents at $48.34 in mid-morning trade on Thursday on the New York Stock Exchange.

Sanofi-Aventis shares were up 41 cents at $42.50, also on the NYSE.