Serono has held talks with Novartis, GlaxoSmithKline, Sanofi-Aventis and Pfizer in recent weeks about a potential $15 billion takeover of the company, The Wall Street Journal reported today.
Serono, based in Geneva, Switzerland, is the world's third largest biotech company by sales.
In a statement, the company said that it has hired investment bank Goldman Sachs Group "to explore various strategic alternatives for the company," adding that "there can be no assurances that any transaction will be consummated."
Any buyer would most likely be interested in Serono's multiple sclerosis drug Rebif, which had sales of $1 billion in 2004. The company also sells drugs to treat infertility and is attempting to develop 30 new medicines for cancer, inflammatory diseases and other therapeutic areas.