Alexion Pharmaceuticals Inc. is a drug manufacturer known for its blood-disease treatment to be the world's most expensive. The drugmaker hired Goldman Sachs Group Inc. to act as an adviser as the firm prepares for a potential takeover bid from Roche Holding AG. This was according to people with familiar with the matter.

An informal approach was taken by Swiss drugmaker, Roche last week about a possible deal for Alexion. However, advance move was rejected, according to the same source who asked not to be named as the matter was held private. Alexion hired Goldman to help the firm negotiate with Roche and see if the offered price for the deal was high enough to get the management interested. Alexion enlisted Goldman to help defend the company if a possible hostile bid occurs, said another person.

Yesterday, Alexion increased by 6.4% in New York that gave the company a market value of around USD23 billion. The company has been in close ties with Goldman after its recent acquisition of Taligen Therapeutics Inc. and Enobia Pharma Corp, according to a date from Bloomberg.