French drug maker Sanofi-Aventis SA says it has agreed to buy US healthcare company Chattem Inc. for about $1.9 billion in cash in a a deal it said would create the world's fifth-largest consumer healthcare company.

Paris-based Sanofi-Aventis says it will offer $93.50 per share to acquire 100 percent of Chattem, a Chattanooga, Tennessee based maker of consumer healthcare products such as Gold Bond skin care creams and Icy Hot pain relief medecine.

In a statement Monday, Sanofi-Aventis said it will launch its public tender offer for Chattem in January, and it expects to complete the acquisition in the first quarter of 2010.