Belgian chemical and pharmaceutical company Solvay SA (SOLB.BT) is ready to defend itself against a lawsuit charging the company and other two drugmakers with conspiring to postpone generic competition for a leading testosterone-replacement drug.

"We are ready to use all means to defend ourselves," said Erik De Leye, spokesman for Solvay. "We are convinced our settlements (with the two other companies) are lawful," he said.

The U.S. Federal Trade Commission has filed the lawsuit charging that Brussels-based Solvay, the maker of the testosterone drug AndroGel, entered into an illegal agreement with generic drug companies Watson Pharmaceuticals Inc. (WPI) and Par Pharmaceutical Cos. (PRX) to delay the introduction of a generic competitor.

AndroGel is the second most important pharma product for Solvay and the U.S. is its main market, said KBC analyst Wim Hoste, who however reiterated its accumulate rating on the stock after the news.

The value of AndroGel is about EUR5 per Solvay share, according to Bernard Hanssens, an analyst at Bank Degroof. Solvay was trading down 1.8% at EUR52.62 as of 1025 GMT Tuesday, in an overall positive Brussels stock exchange.

The U.S. commission filed the lawsuit jointly with the California attorney general's office in a Riverside, Calif., federal court.

-By Alessandro Torello, Dow Jones Newswires; +32 2 741 14 88; alessandro.torello@dowjones.com

(Brent Kendall in Washington contributed to this article.)

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